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Text File | 1996-09-26 | 60KB | 1,642 lines

The req.library is a run time re-entrant library that is designed to make it easier for programmers to use powerful, easy to use requesters for communicating with users. The requester library includes such functions as a color requester, file requester, message display requester and many functions to make the creation of gadgets for your own custom requesters easier. Req.library was written by Colin Fox (of Pyramyd Designs) and Bruce Dawson (of CygnusSoft Software). Req.library is a freely distributable library that may be used in commercial products without paying any royalties. We encourage you to use the requester library in all of your programs, to make them easier to write, and to use. Req.library is not public domain. The requester library and all documentation and example programs are all copyright 1989. The requester library must be distributed with the documentation file (req.doc), and the three include files (req.h, reqbase.h and reqbase.i). Req.library is dedicated to the programmers who make the Amiga shine the way it was meant to. OverView: All of the req.library functions that bring up requesters allow you two ways of specifying what screen you would like the requester to appear on. The first way is the more efficient way, because you only have to set it up once and then it takes care of things automatially. There is a field in all process structures called the pr_WindowPtr. This pointer is used by DOS to decide where to put it's requesters. If pr_WindowPtr contains a zero, requesters go on the workbench screen. If it contains the address of a window, then requesters go on that window's screen. If it contains a negative one, then no DOS requesters come up. The req.library requesters all use this variable, if they are called from a process . However, if the pointer is -1, the req.library functions do still appear, on the workbench screen. The second way was put in mainly so that the requesters can be called from tasks. Since a task does not have a process structure, it also lacks a pr_WindowPtr. Therefore, all of the requester functions which can be used from a task (currently everything except the file requester) can be passed a window pointer, either as a parameter or as an element in a structure. Important: This pointer takes precedence over the pr_WindowPtr so if you wish the requesters to use the pr_WindowPtr you must zero the window fields that the routines are expecting. In the case of fields in a structure this can be easy as long as you make sure your structure defaults to being zero everywhere. Setting the pr_WindowPtr is quite a simple matter. All you have to do is do a FindTask((char *)0); which returns a pointer to your own task and your own process (a task structure is the first element of a process structure). Then you simply preserve the old value of pr_WindowPtr (VERY IMPORTANT!!!) and put a window pointer into it. eg: /* Find my task. */ myprocess = (struct Process *)FindTask((char *)0); oldwindowptr = myprocess->pr_WindowPtr; myprocess->pr_WindowPtr = window; or: MOVE.L 4,A6 MOVE.L #0,A1 SYS FindTask ;Find my task. MOVE.L D0,_myprocess MOVE.L D0,A0 MOVE.L pr_WindowPtr(A0),_oldwindowptr MOVE.L _window,pr_WindowPtr(A0) Before your program exits it is VERY important that it restore the previous value of pr_WindowPtr. If you don't, then your program will work in some situations, but will BLOW UP in others. For example, if you execute (without using the 'run' command) a program, which then sets the pr_WindowPtr to point at one of its windows and the exits without restoring it, then the next time a DOS requester tries to appear... BOOM! The machine will probably crash as DOS tries to open a requester on a now closed screen. Therefore, before leaving: myprocess->pr_WindowPtr = oldwindowptr; or: MOVE.L _myprocess,A0 MOVE.L _oldwindowptr,pr_WindowPtr(A0) One final note. The pr_WindowPtr field exists in the process structure. This means that a task does not have this field. Therefore, if you want to call one of the requester library functions from a task, you will not be able to specify what screen you would like the requester to appear on by setting the pr_WindowPtr field. All of the functions that open requesters and can be called from a task (the file requester/font requester is the only one that can't be called froma task) have some other way of specifying which screen you would like them to open on. They will have either have a field in the structure which you must pass them or a parameter which can contain a window pointer to one of the windows on your custom screen. If this pointer is non-zero then it overrides the pr_WindowPtr field. By opening the requester library, you not only gain access to all of the functions documented below, but to some other goodies as well. Req.library needs and therefore opens several other libraries, including dos.library, intuition.library, graphics.library and the console device. All of these pointers are stored in the ReqLib structure which you get a pointer to when you open the req.library. Therefore, you can save yourself a little bit of code by grabbing these fields after opening the requester library. The only thing to beware of is don't use these values after you have close the requester library, because at that point there is no guarantee that they will still be valid. In addition to these libraries, the Images pointer in the req library structure points to a set of ten small images (four arrows and ssix letters) which have are guaranteed to be in chip memory. These can be used if your program requires this type of images. One thing to keep in mind when using the gadget creation routines is that there isn't any way for us to check that you have passed us a pointer to the correct size of buffer, so you _must_ make sure that you are allocating the right amount of memory. -------------------------------------------------------------- Here's a quick list of the functions available: -------------------------------------------------------------- Center..................Center a new window over the mouse. SetSize.................Prop gadget handling routines (32 bit) SetLocation ReadLocation Format..................sprintf() format routine SimpleRequest...........Starter gluecode to TextRequest- Single gadget TwoGadRequest...........Starter gluecode to TextRequest- Two gadgets FileRequester...........FileRequester routines PurgeFiles ColorRequester..........a colorrequester MakeGadget..............Gadget creation routines MakeString MakeProp MakeButton MakeScrollBar...........3 part gadget; 2 arrows and a prop. Horizontal or Vertical LinkGadget..............Gadget creation routines that self-hook into the newwindow LinkStringGadget........gadget list. LinkPropGadget DrawBox.................Draw a box (x1y1)(x2y2) in one command GetFontHeightAndWidth...return height and width of current font RealTimeScroll..........scroll routine used in file requester TextRequest.............Powerful requester function GetString...............Get a line of text from the user GetLong.................Get a signed long from the user RawKeyToAscii...........Convert raw key to ascii ---------------------------------------------------------------- NAME Center SYNOPSIS Center( &nw, x, y) A0 D0 D1 struct NewWindow *nw; USHORT x,y; DESCRIPTION Center() is used to adjust a NewWindow structure so that the window that it opens will appear immediately under the mouse. The x,y values are used to specify which part of the window you would like to appear underneath the mouse. If x or y is zero, that tells Center() to position the window so that the window center (in the x or y direction respectively) is underneath the mouse. If x or y is positive, that tells Center() to position the window so that the mouse is that many pixels from the left or top edge of the window respectively. If x or y is negative, that tells Center() to position the window structure so that the mouse appears that many pixels from the right or bottom edge of the window respectively (ie; x = -10 tells Center to position the mouse ten pixels to the left of the right edge). If it is impossible to position the window exactly where requested (if the mouse pointer is too close to the edge of the screen) then this routine will position the window as close as possible to the correct location. To allow this routine to work accurately it is necessary to have already initialized the new window structure to specify on what screen the window is going to be open. ie; you should set the Type and Screen fields before calling Center(). This routine disturbs no registers. RETURNS nothing SEE BUGS None known ;-------------------------------------------------------------------- NAME SetSize SYNOPSIS SizeVal=SetSize(MaxValue,ViewSize) D0.W D0.L D1.L short SizeVal; long MaxValue,ViewSize; DESCRIPTION This routine is designed to correctly handle sizing a prop gadget to a range. The range is given in in MaxValue/ViewSize. MaxValue is the maximum value that this prop is supposed to be able to represent. Viewsize is how large the display area is. For instance, if your maximum value was 200 (files, for example), and your viewsize was 15 (lines of text), then you would call this as so: SizeVal=SetSize(200,15); Then you would put SizeVal into the appropriate PropInfo structure element (in the case of the file requester, that would be VertBody). RETURNS The 16 bit value to be put into the PropInfo structure of the prop gadget. SEE SetLocation, ReadLocation BUGS Bugs? what bugs? ;-------------------------------------------------------------------- NAME SetLocation SYNOPSIS NewLoc = SetLocation(MaxValue,ViewSize,Value); D0 D0 D1 D2 short NewLoc; long MaxValue,ViewSize,Value; DESCRIPTION When you have a prop gadget that you wish to directly set, then this is the routine to use. It allows you to pass any 32 bit value and properly set the gadget. RETURNS The return is the value to put into either HorizPot or VertPot, depending on what orientation you have the gadget. BUGS n/a EXAMPLE SEE SetSize(),ReadLocation() ;-------------------------------------------------------------------- NAME ReadLocation SYNOPSIS LocVal=ReadLocation(MaxValue,ViewSize,PotValue) D0 D0.L D1.L D2.W long LocVal,MaxVal,ViewSize; short PotValue; DESCRIPTION If you prop gadget has been moved, this is the routine that you would use to determine where it's been moved to. RETURNS Returns the decoded value of the prop, as an unsigned 32 bit. This is the element number (line number usually) that should be displayed on the first line of your display window. SEE SetSize(), SetLocation() BUGS n/a EXAMPLE ;-------------------------------------------------------------------- NAME Format SYNOPSIS Format(Buffer,string,values) A2 A0 A1 char *Buffer,string[]; char **values; DESCRIPTION This does the same thing as sprintf(), except that it isn't in the stdio library, and doesn't use up very much room. This function uses the ROM function RawDoFmt to do the print() style formatting. This routine does not allow the use of all of the '%' directives (for example, floating point numbers can not be printed with this). For full documentation on what directives are supported, see the documentation on RawDoFmt. This is the routine that TextRequest (and therefore SimpleRequest and TwoGadRequest) use for their text formatting, so these restrictions apply to them also. The RawDoFmt routine also assumes that 'int's are sixteen bits long. Therefore, if you are using a compiler with an int size of thirty-two bits and you want to print an int or a short, you must use '%ld', rather than '%d'. RETURNS The number of characters in the formatted string. BUGS none known EXAMPLE Format(Buffer,"There are %d changes to the file %s.",numchanges, filename); Format(Buffer,"%x is a hex number, %c is a character.", num, chr); SEE TextRequest, SimpleRequest, TwoGadRequest. Further information on printf() style formatting is available in the AutoDocs on RawDoFmt and in C manuals discussing printf(). ;-------------------------------------------------------------------- NAME ColorRequester SYNOPSIS NewColor=ColorRequester(DesiredColor); D0 D0 long DesiredColor; DESCRIPTION This is a full-fledged color requester. It is intelligent enough to open with the right number of colours in the palette automatically. It shows you both the colour you are working with, and the numerical RGB value of that colour. It has Spread, Undo, Ok and Cancel functions. Planned is the addition of HSV. The cursor keys move the color-cursor around the palette, RETURN selects the current color and ESC cancels out. You pass this routine the color that you would like initially highlighted (typically the current drawing colour). The ExtendedColorRequester function has slightly more options, but is slightly more work to call. RETURNS Color number that the user selected, -1 if the user cancels the colour requester. The changed colours will be in the viewport structure for your screen. SEE ExtendedColorRequester BUGS none known. EXAMPLE newcolor = ColorRequester(oldcolor); ;-------------------------------------------------------------------- NAME ExtendedColorRequester SYNOPSIS NewColor=ExtendedColorRequester(&(struct ExtendedColorRequester) D0 A0 struct ExtendedColorRequester colorreqstruct; DESCRIPTION This call brings up exactly the same color requester as the ColorRequester call. The only difference is that this routine allows you to specify more parameters. The difference is actually quite small right now, because there is only one additional parameter that can be passed through this entry point. This is the ecr_window parameter, used to specify what window (and hence what screen) the color 'requester' appears on. This parameter is rarely needed because the window the requester opens up on can be specified by setting the pr_WindowPtr field in your process structure to the address of your window structure (see the beginning of the docs for an overview on this procedure). The only time this entry point is needed, currently, is if you try to bring up the color requester on a custom screen from a task, since a task does not have a pr_WindowPtr and can therefore not specify the window and screen. RETURNS Color number that the user selected, -1 if the user cancels the colour requester. The changed colours will be in the viewport structure for your screen. SEE ColorRequester BUGS none known. EXAMPLE /* This should generally be declared as a global variable */ /* so that all of it's elements get initialized to zero. */ /* If you declare it as a local variable, be sure to zero */ /* all of the fields, even the unused ones. */ struct ExtendedColorRequester colorstruct; colorstruct.defcolor = 0; colorstruct.window = mywindow; newcolor = ExtendedColorRequester(&colorstruct); ;-------------------------------------------------------------------- NAME MakeGadget SYNOPSIS MakeGadget(Buffer,String, X, Y) A0 A1 D0 D1 struct Buffer *GadgetBlock; char *String; long D0,D1; DESCRIPTION This routine prepares a buffer to be a standard BOOLEAN text gadget. This is a simple way of producing gadgets for code that must be reentrant, and it is more efficient than defining gadgets in data statements. The routine initializes the gadgets to a set of 'standard' values that should cover most cases and then links the four parts of the GadgetBlock together. Buffer is a pointer to a unitialized GadgetBlock, which contains the necessary Gadget, Border, border pairs and IntuitText structures needed to render a boolean gadget with a border and some text. String is a pointer to the text that should appear inside the gadget. The gadget is automatically sized to match the strings length. X and Y are the gadgets initial position, they are simply copied into LeftEdge and TopEdge in the gadget structure. RETURNS SEE BUGS EXAMPLE ;-------------------------------------------------------------------- NAME MakeString SYNOPSIS MakeString(Buffer,StringBuff,UndoBuff,MaxWidthBits,MaxNumChars, X, Y) A0 A1 A2 D0 D1 D2 D3 struct Buffer *StringBlock; char *StringBuff; char *UndoBuff; long MaxWidthBits, MaxNumChars, X, Y; DESCRIPTION As with all of the MakeGadget functions, this one prepares a buffer to be used as a string gadget, that may be used re-entrantly. The buffer need not be cleared first. This means that you may create a temporary gadget on the stack. The StringBuff is where the body of text inside the gadget will reside. When the gadget is activated, the text in StringBuff is automatically copied (by intuition) into UndoBuff. This allows you to type Amiga-Q and get the old string back. This field may be null if you wish to have no undo. MaxWidthBits is the width of the frame around the gadget. MaxNumChars is the maximum number of characters that you will be able to type into the gadget, including the terminating zero on the string. MAKE SURE that this number is no greater than your StringBuff size, or else you're going to be typing over memory that isn't yours. X,Y are the position of the upper left hand corner of the gadget. The border is actually 2 pixels above and to the left of this corner. RETURNS Nothing SEE MakeGadget,MakeProp,MakeScrollbar,LinkGadget,LinkProp,LinkString ;-------------------------------------------------------------------- NAME MakeProp SYNOPSIS MakeProp(Buffer,Width,Height,Flags) A0 D0 D1 D2 struct Buffer *PropBlock; long Width, Height, Flags; DESCRIPTION This routine prepares an un-initialized buffer for use as a prop gadget. Buffer, on return, will contain the gadget, along with the necessary PropInfo and Image structures, all linked together. Width is the with of the container, in pixels. Height is the height of the container in pixels. The Flags parameter is where you decide if you want FREEHORIZ, FREEVERT, or both. It is simply copied into the gadget flags field. RETURNS Nothing ;-------------------------------------------------------------------- NAME DrawBox SYNOPSIS DrawBox(rp,MinX,MinY,MaxX,MaxY) A1 D0 D1 D2 D3 struct RastPort *rp; long MinX,MinY,MaxX,MaxY; DESCRIPTION This routine allows you to draw a simple box in one command. It draws the box in APen color, in the current draw mode, with the current line pattern. (MinX,MinY) are the upper left corner of the box, and (MaxX,MaxY) are the lower right. The pen is left at the upper left corner (MinX,MinY). ;-------------------------------------------------------------------- NAME MakeButton SYNOPSIS MakeButton(Buffer,Image,Image2,Width,Height,Depth) A0 A1 A2 D0 D1 D2 struct TwoImageGadget *Buffer; char *Image; /* Pointer to the actual bitplane data */ char *Image2; /* Pointer to the second image. */ long Width,Height,Depth; DESCRIPTION The purpose of this routine is one similar to MakeGadget, but instead of using text for the button, it uses a graphic. You supply a bitmap, and MakeButton will use it in it's rendering. You may have either one or two images, the routine handles it routinely. If you supply one image, then this sets GADGHCOMP, and if you have two images, it sets GADGHIMAGE. RELVERIFY is always set, so as long as you the user is pressing that gadget, the alternate highlight is shown. Buffer has room for two images. Image is a pointer to the actual image data, in CHIP memory, for this gadget. Image2 is a pointer to the alternate image data. Width and Height make up the size of your image. Depth is how many bitplanes of data you've supplied. BUGS It's not really a bug, but if your images aren't the same size, then one won't erase the other when it is drawn, so you may be showing an image with traces of the other one left there. ;-------------------------------------------------------------------- NAME MakeScrollBar SYNOPSIS MakeScrollBar(Buffer,Flags,Size,X,Y) A0 D0 D1 D2 D3 struct ScrollBlock *Buffer; long Flags,Size,X,Y; DESCRIPTION This is a special routine that creates a scrollbar (which consists of a prop gadget and two arrows) and you handle it like it's a single gadget. You may have either a horizontal scrollbar, or a vertical scrollbar. These scrollbars are very much like the ones in workbench window borders. These use slightly different images on the arrows, however. The way you determine how this set up and oriented is by flag combinations. If you wished to put a scrollbar in the bottom border of a window, then you would pass (in flags): Flags = (HORIZSLIDER | GRELBOTTOM | GRELWIDTH) If you wished it in the right border: Flags = (VERTSLIDER | GRELRIGHT | GRELHEIGHT) The idea is to allow you to manipulate the scrollbar as though it were a single gadget, not three. If you pass confusing flags (like GRELBOTTOM|GRELHEIGHT) then it is undefined what will happen. If all you want is a simple scrollbar that doesn't size, then just set VERTSLIDER or HORIZSLIDER. SEE ;-------------------------------------------------------------------- NAME PurgeFiles SYNOPSIS PurgeFiles(&FileRequesterStructure) A0 DESCRIPTION Clear up all memory and file locks allocated by the file requester. This routine must be called before your program exits if you use the file requester with either FRQEXTSELECTM bit set or the FRQCACHINGM bit set. The first bit is if you want the user to be able to select multiple files. The file requester has to allocate a linked list of file names which this function will purge. The FRQCACHINGM bit is set if you want the file requester to remember the contents of a directory between calls. This routine can be called any time you want the buffers and file locks purge. RETURNS This routine does not return anything. SEE FileRequest BUGS None known. EXAMPLE main() { FileRequest(&FileRequesterStructure); . . . PurgeFiles(&FileRequesterStructure); } ;-------------------------------------------------------------------- NAME GetFontHeightAndWidth SYNOPSIS DESCRIPTION This allows you quick access to the font attributes set by the user in preferences. The font width is returned in D0 and the height is returned in D1. RETURNS SEE BUGS EXAMPLE ;-------------------------------------------------------------------- NAME LinkGadget SYNOPSIS LinkGadget(Buffer,String,nw, X, Y) A0 A1 A3 D0 D1 struct GadgetBlock *Buffer; char *String; struct NewWindow *nw; long X,Y; DESCRIPTION This is actually a superset of the previous command MakeGadget. What this does is automatically link the gadget into your NewWindow structure's gadget list. No registers are disturbed. SEE MakeGadget BUGS n/a ;-------------------------------------------------------------------- NAME LinkStringGadget SYNOPSIS LinkStringGadget(Buffer,StringBuf,UndoBuf,nw, WidthBits,NumChars, X, Y) A0 A1 A2 A3 D0 D1 D2 D3 struct StringBlock *Buffer; char *StringBuf; char *UndoBuf; struct NewWindow *nw; long WidthBits,NumChars,X,Y; DESCRIPTION This is number 2 in the LinkGadget routines. This one obviously links the string gadget to the window's gadget list. In fact, the only difference between this and the MakeString routine is the addition of the NewWindow pointer. SEE MakeStringGadget ;-------------------------------------------------------------------- NAME LinkPropGadget SYNOPSIS LinkPropGadget(Buffer,nw, Width, Height, Flags, LeftEdge, TopEdge) A0 A3 D0 D1 D2 D3 D4 struct PropBlock *Buffer; struct NewWindow *nw long Width,Height,Flags,LeftEdge,TopEdge; DESCRIPTION Here we have a superset for MakeProp. It works exactly the same as MakeProp, except that it attaches the gadget to the head of the list in the window. SEE MakeProp ;-------------------------------------------------------------------- FileRequester NAME FileRequester - bring up a file/font requester. SYNOPSIS success = FileRequester(&FileRequesterStructure) D0 A0 FUNCTION Bring up a fully intuitionized file/font requester (actually a window) and let the user select a file/font. INPUTS &FileRequesterStructure - pointer to an initialized (can be initialized mostly to zeroes) file requester structure. RESULT Returns TRUE or FALSE to say whether the user selected a file or not. The file name(s) or font selected are then found by looking at the file requester structure whose address was passed. For ideas on customizing the file requester for your particular system (thus overriding the defaults used by programmers who use the file requester) see the customizefile.asm file. BUGS Problem with an Intuition bug that messes up the current active window if a window closes when one of its string gadgets is still active. This bug show up if you run the file requester straight from a CLI window and then exit it with Amiga-L. I have heard that it resets some window flags when run on a custom screen, but I believe this is a feature of Intuition, not of the file requester. SEE ALSO PurgeFiles The file requester in the requester library allows to put a powerful and easy to use file requester into your programs with a minimum of work and at a very small expense in program size. The file requester was designed to be as easy as possible to call, while not sacrificing power. To get the file requester to come up all you need to do (after opening the requester library of course) is to allocate space for a FileRequester structure and then call the file requester with the address of this structure, with all fields initialized to zero, like this: struct FileRequester MyFileReqStruct; success = FileRequester(&MyFileReqStruct); The function will return either one or zero for success or failure respectively. You can specify what screen the file requester should appear on in one of two ways. If you want it to appear on a custom screen, then the best way is to set the pr_WindowPtr field in your process structure to point at one of the windows on your screen (this should be done anyway, so that DOS requesters appear on your custom screen). This field is looked at by all functions in the requester library so this way is the simplest method. The other way, which overrides the pr_WindowPtr field is to initialize the frq_Window field to point at one of your windows. If this field is non-zero, it is used instead of the pr_WindowPtr field of your process structure. Important note: It is VERY important that you reset the pr_WindowPtr field back to its original value before your program exits. If you don't, the next program run may try to open a requester window on a now closed screen. The file requester was carefully designed so that it could be called without having to initialize very many fields. This is demonstrated by seeing that it is possible to call it without initializing any fields. There are a few fields that are necessary to actually get any use out of it, but very view. Those few are documented in the following paragraph. Although you can bring the file requester up without initializing any fields there are a couple of fields that you will definitely want to initialize. The file requester isn't much use unless you get a file name back out of it, and for this you need to initialize the Dir and File fields. These two fields should point to character arrays that are, respectively, DSIZE+1 and FCHARS+1 bytes long. When the file requester is first run the file requester looks in these arrays for the default directory and file names and if the user selects a file name the directory and file name are copied back into these arrays. You will probably want to initialize the Title field with the message that you want to have appear at the top of the file requester window. If you initialize the PathName field (it should point an array of at least DSIZE+FCHARS+2 characters) then when the user selects a file, the complete path name will be put into this array. The Window field is used to specify what window the file requester is associated with. This is used to get the file requester to show up on a custom screen. Generally this field should be unnecessary. There is a variable provided in a process structure which is used for this purpose. Any program that opens a custom screen and uses any DOS functions should set the pr_Window pointer in their process structure to a pointer to their window so that DOS requesters will show up on their custom screen. If you do this, then the file requester will also show up on your custom screen. If you are not using a custom screen then you don't need to set the pr_Window pointer or the Window field in the file requester structure. Note: If you do set the pr_Window structure in the process structure, be sure to return it to its old value before your program exits. If the extended select bit is set in the Flags field then the MaxExtendedSelect fields specifies the maximum number of files that the user can select. This is ignored if the extended bit isn't set in the Flags field. numlines and numcolumns specify the maximum size that the file box will be in characters. If the system is low on memory, or the screen is too small, these will be shrunk as necessary. devcolumns is the number of columns of characters wide that the device box will be. The Flags field can currently contain seven different flags. The first flag, FRQSHOWINFOM, specifies whether or not '*.info' files (files containing information for icons) should be filtered out. The default is for them to be filtered. The FRQEXTSELECTM flags specifies whether extended select is wanted. If you set this flag then you should probably also set the MaxExtendedSelect field. If you don't then the maximum number of files the user will be able to select will be 65536, which is a bit high for most purposes. Note: If you use this bit then you _must_ call PurgeFiles() with the address of your FileRequester structure after the last time you call the file requester, in order to free up any memory used in the extended select structures. When the user selects multiple files, a linked list of the file names selected (not including the directory name) will appear in the ExtendedSelect field. The list is a linked list of ESStructures. The directory name which should be prepended to all of these names will appear in the array pointed to by the Dir field. The FRQCACHINGM flag specifies whether or not directories are cached from one call to the next. This is a very handy features, especially for those who lack hard drives. However, if this features is used, you _must_ call the PurgeFiles() routine with the address of your FileRequester structure after the last time you call the file requester, in order to free up any memory used in caching. As well as being a file requester, this routine can be used as a font requester too. Just set the FRQGETFONTSM flags to turn it into a font requester. You should also put the name 'fonts:' in the Dir array. The file/font requester will return a one or zero for success or failure as usual, the font name will be returned in the File array and the font size and style will be returned in the FontYSize and FontStyle fields. Note that the font requester allows the user to change the directory where the fonts are read from. Although you should put 'fonts:' there, you should allow for the possibility that the user might change the directory. They might, perhaps, have a separate disk full of fonts. The simplest way to deal with fonts coming from different directories, is to set the PathName field instead of the Dir field. You can then use the string in the PathName field (which will contain the directory and font name) as the font name. If you don't do this, then you have to concatenate the font name and the directory name yourself. If you use the PathName variable then it is quite reasonable to leave the File field blank, since all the information you need can be obtained from the PathName string. The FRQINFOGADGETM flag specifies whether or not a hide/show info gadget should appear on the file requester. This lets the user toggle the state of the FRQSHOWINFOM flag to decide whether or not to let '*.info' files show up. This is not recommended for most programs, since most users have no reason to look at '*.info' files. The default is to _not_ have this gadget show up. The FRQHIDEWILDSM flag specifies whether or not to have 'show' and 'hide' string gadgets. These gadgets let the user use wildcards to specify which files should show up. All files are first compared against the 'show' gadget. If they fail the comparison, they are not displayed. Then they are compared against the 'hide' gadget. If they match here then they are not displayed. If the gadgets are empty, no comparisons are done. Important note: Even if these gadgets are not displayed, the comparisons are still done on the data which is in the Hide and Show fields of the file requester structure. The standard AmigaDOS wildcards (including '#', '?', '|' and '*') are supported. Normally the file requester appears centered under the mouse pointer. If you would like to specify its opening position you must set the ABSOLUTEXYM flag and then put the x,y position in WindowLeftEdge and WindowTopEdge. If you feel that the file requester's cached directories (selected by FRQCACHINGM) should be purged whenever the directory has been changed, then set FRQCACHEPURGEM field and the file requester will check the dates whenever it is opened. If you feel that the file requester should never cache directories unless it manages to read in the entire directory before the user sends it away, then set the FRQNOHALFCACHEM flag. This flag will cause the file requester to automatically flush any incompletely read directories when it exits. If you would like your directories to appear in 'natural' order instead of alphabetically sorted, set the FRQNOSORTM flag. If you would like the file requester to appear without a drag bar or depth arrangement gadgets, set the FRQNODRAGM flag. If you are using the file requester to select a filename to save to, you should set the FRQSAVINGM flag. Similarly, if you are using the file requester to select a filename to load from, you should set the FRQLOADINGM flag. These flags are not currently used by the file requester, but they may be used in the future. They also make it easier for people who want to personalize the file requester to make it behave differently for loading vs. saving. The various color fields let you specify the colors of many aspects of the file requester. If they are left as zero then the file requester uses various non-zero certain default values for them. The WindowLeftEdge and WindowTopEdge fields are covered in the section on the ABSOLUTEXYM flag. The FontYSize and FontStyle fields are covered in the section on the FRQGETFONTSM flag. The ExtendedSelect field is covered in the section on the FRQEXTSELECTM flag. The Hide and Show fields are covered in the section on the FRQHIDEWILDSM flag. Set this bit if you are selecting a file to save to. Set this bit if you are selecting a file(s) to load from. These two bits (save and load) aren't currently used for anything, but they may be in the future, so you should remember to set them. Also, these bits make it easier if somebody wants to customize the file requester for their machine. They can make it behave differently for loading vs saving. The four BufferPos and DispPos variables are copies of the equivalent variables from the four string gadgets. This is so that when the file requester goes away and then is brought up again, the cursor in the string gadgets will appear in the same places as before. These fields should not need to be touched by the programmer. The rest of the fields are private. Don't go touching them. We guarantee to move them around and change their meaning, just to make sure that nobody tries to use them. They are largely concerned with keeping track of memory used in directory caching. This memory is freed with the PurgeFiles() routine. That's all you should need to know. ;-------------------------------------------------------------------- RealTimeScroll NAME RealTimeScroll - do the calculations necessary for a responsive, pixel resolution, real time scroll routine. SYNOPSIS RealTimeScroll(&ScrollStruct); A0 FUNCTION Make the implementation of real time scrolling area easier and make the real time scrolling area more responsive to the user by doing pixel resolution scrolling and by checking the current position of the scroll bar in mid scroll. This routine calculates how far to scroll each time and calculates which lines of text, graphics etc. need to be redrawn to fill in the empty area. INPUTS &ScrollStruct - pointer to an initialized scroll structure. RESULT This routine returns no result code. BUGS None known SEE ALSO n/a It is relatively easy to implement a real time scrolling area, but the most obvious implementations suffer from a lack of responsiveness. Typically the routines look at where the scroll bar is, calculate where to scroll to, scroll there in several jumps to make the scrolling look smooth, and the examine the scroll bar again to see if it has moved. This means that there are periods, perhaps annoyingly long, where the program may be scrolling in one direction while the scroll bar is being dragged in another. The answer is to examine the scroll bar to find out the desired location, scroll partway towards the destination and then recheck the scroll bar's location. This can greatly increase the responsiveness, since the program is checking after every ScrollRaster() call, instead of after a dozen or more. However, the calculations, especially of which lines need to be refreshed and where, get somewhat more complicated. This routine is designed to simplify this situation by taking care of as many of the messy details as possible. First you must initialize the scroll structure. The TopEntryNumber, NumEntries and NumLines fields describe where the data is currently. NumEntries is the number of lines of data in total, NumLines is the number of lines that are visible, and TopEntryNumber is the line number of the first line visible (it therefore ranges from zero to NumEntries - 1). LineSpacing is the number of pixels high that each line of data is. For text this will typically be eight or nine (for eighty or sixty column topaz). This can be set to one if your data is continuous (as in the case of some graphics). PropGadget is a pointer to the prop gadget which is being used to control this scroll area. RedrawAll is a pointer to a function that you must supply to redraw the entire visible window. This routine is called whenever the user gets so far ahead of the scroll routine that scrolling to where the users wants to be would take to long. Before calling this routine, the ScrollStruct that was passed to this routine is updated with the desired TopEntryNumber so that your routine will know which data to redraw. ReadMore is an optional routine that will usually not be used. It is used if more data is being added while the scrolling is going on. This is used, for instance, by the FileRequest in the requester library, to continue attempting to read the directoy while the user is scrolling. Leave this set to zero if you don't need it. It is only called when no scrolling is being done, but the user has not released the scroll bar. ScrollAndDraw is the most important routine. This routine, which you must supply, is called whenever the data must be scrolled. The actual scrolling and redrawing of the data is done by this routine, but because the scroll amount, the lines to be drawn and the number of lines to be drawn are passed to this routine, the routine is fairly simple. Four parameters are passed to this routine: ScrollAndDraw(firstlinenum, firstliney, scrollamount, numlines); All four parameters are passed as longs, both on the stack and in D0-D3, so that the routine can easily be written in either C or assembler. When the ScrollAndDraw, ReadMore or RedrawAll routines are called, A4, A5 and A6 all contain the same values they contained when RealTimeScroll was called. This allows programs written in C using the small data model to be able to access their data properly from these routines without any special work. All other registers (except those that are used to pass parameters in) could contain anything. ;-------------------------------------------------------------------- TextRequest NAME TextRequest - bring up a text requester with one to three gadgets and get a response. SYNOPSIS result = TextRequest(&TRStructure); D0 A0 FUNCTION Bring up a requester (actually a window) containing a message to the user and give him a choice of from one to three different responses. The window automatically sizes to fit the text and printf() style formatting can be used by TextRequest() to generate the message to the user. INPUTS &TRStructure - pointer to an initialized text requester structure. RESULT Returns either zero, one or two, depending on which gadget the user clicks on. All of the gadgets are optional, so that the requester can be used to bring up requesters that give the user a message, without demanding an answer, by having only a single gadget. The gadget in the lower right hand corner (the negative gadget) returns a zero, the gadget in the lower left hand corner (the positive gadget) returns a one and the gadget in the middle returns a two. If none of these three gadgets are requested, a close gadget is attached to the window and it returns a zero. BUGS If any line of the text to be printed is too long, then the requester will attempt to open up an impossibly large window, which will fail and the requester will return a zero. The buffer used for formatting the text is 5000 bytes long, so no messages can be longer than this. SEE ALSO SimpleRequest TwoGadRequest The purpose of this routine is to make it as easy to print formatted messages in intuitionized window with gadgets as it is to print them on the CLI screen. For maximum ease of use, at a loss of flexibility, please see the functions SimpleRequest and TwoGadRequest which are simply glue code functions to make calling TextRequest a trivial matter. If you want the text requester to appear on a custom screen, then you must set the pr_WindowPtr field in your process structure to point at one of the windows on your screen (this should be done anyway, so that DOS requesters appear on your custom screen). This field is looked at by all functions in the requester library so this way is the simplest method. Important note: It is VERY important that you reset the pr_WindowPtr field back to its original value before your program exits. If you don't, the next program run may try to open a requester window on a now closed screen. The structure whose address is passed to this routine must be initialized first. The Text field is initialized with the body of the text you would like displayed. This text can contain both printf() style formatting and end of line characters ('\n' in C, ascii 10 in assembler). The printf() style formatting, is expanded out into the final text string using the parameter list which is pointed to by the Controls field. Line feeds are used, as usual, to specify a new line, thus allowing very long and complex messages to be displayed. The are some limitations on the types of printf() formatting that can be used. Since the RawDoFmt() function of the ROM is used to do the formatting, only functions supported by it can be used. For complete documentation, see the documentation of the RawDoFmt() command. The main things to be aware of is that floating point numbers can not be printed, and, if you are using a compiler that uses thirty-two bit ints then we will have to specify '%ld' to print an int, since the RawDoFmt command assumes an int size of sixteen bits. The Controls field points to a list of parameters, one for each of the '%' parameters in the Text field. Normally these will be pushed on to the stack and the stack pointer copied into the Controls field. The first parameter used (the first one to occur in the string) should be at the beginning of the list, that is, at the lowest address, the one pointed at by the Controls parameter. The Window field can be used to specify what screen you would like the requester to appear on. This field is usually not necessary since the same information can be conveyed in the pr_WindowPtr field of your process structure. However this field was left in so that the TextRequest function could be called from a task (which lacks a process structure and therefore a pr_WindowPtr field). If this field is non-zero or if the calling program is a task then this field takes precedence over the pr_WindowPtr field. MiddleText, PositiveText and NegativeText are the pieces of text used for the three gadgets. These three gadgets, when present, are placed in the middle, the left and the right of the window respectively. All three gadgets are placed along the bottom of the window. All of the gadgets are optional. If a gadget is not wanted, the text pointer should be set to zero. The values returned if the user clicks on these gadgets are two, one or zero, respectively. If none of the gadgets are present (if all of the text fields are zero) then a standard CLOSEWINDOW gadget is attached to the window. This gadget returns a zero. The requester attempt to appear so that the negative gadget is underneath the mouse pointer. If the negative gadget is not present it will attempt to appear so that a different gadget is underneath the mouse pointer. This is to make it as convenient as possible for the user to respond to, and especially to respond negatively to, the requester. In addition to responding to the requester with the mouse, keyboard shortcuts are available. The user can type ESC, 'N', 'Q' or 'B' as a shortcut to clicking on the negative gadget. The user can type 'Y' or 'V' as a shortcut to clicking on the positive gadget and can type 'M' as a shortcut to clicking on the middle gadget. The Title field of the structure should either point to a null terminated string to be used in the windows title bar or should be null. The KeyMask field is used to regulate the use of keyboard shortcuts. The qualifier field of all keyboard messages is ANDed with this field, and the keypress is ignored if the result is zero. Therefore, to enable all keypresses to be used as keyboard shortcuts, initialize this field to $FFFF. To turn off the keyboard shortcuts, initialize this field to 0. To force the user to hold down the left or right amiga key, initialize this field to AMIGAKEYS. The textcolor, detailcolor and blockcolor fields can be left unitialized (ie; set to zero) if you wish, in which case the requester will use the default values of one, zero and one respectively. The textcolor field is used for the color of the actual text message and the detail and block color fields are simple copied into the fields of the same name in the new window structure. ;-------------------------------------------------------------------- SimpleRequest NAME SimpleRequest - bring up a text requester and wait for the user to acknowledge it. SYNPOSIS SimpleRequest(string, parameterlist, , ,) A0 A1 FUNCTION Bring up a requester (actually a window) containing a message to the user and wait for the user to acknowledge it. The window automatically sizes to fit the text and printf() style formatting can be used by TextRequest() to generate the message to the user. INPUTS string - a null terminated string, containing printf() style formatting commands if desired. parameterlist - the parameters corresponding to the printf() style formatting commands in the string. In C these are listed after the control string, exactly as with printf(). In assembler, the address of the list of parameters is put in A1. RESULT No result code is returned. BUGS See TextRequest SEE ALSO TextRequest TwoGadRequest This function was designed to make it as easy to give messages to the user and await acknowledgment in an intuition style requester as it is using printf() and getc(). Simply replace almost any call to printf() with a call to SimpleRequest and a requester will appear and not disappear until the user acknowledges it (either with a keystroke or with the mouse). Example: SimpleRequest("There have %d changes made to this file.", numchanges); Please see the TextRequest documentation for further important details. This routine is simply a few lines of assembler glue code for the TextRequest routine. The TextRequest routine is a little bit more complicated to use, but it allows correspondingly more flexibility. It is fairly simple to modify the glue code to allow still more high level entry points to the TextRequest routine. This is a complete program that makes use of the SimpleRequest function from assembler, and demonstrates a few of the features of Format (which is used by SimpleRequest). ;-------------------------------------------------------------------- ;-----CUT HERE---------------CUT HERE-------------------------------- ;-------------------------------------------------------------------- INCLUDE "libraries/reqbase.i" public SimpleRequest public _ReqBase,_main ;-------------------------------------------------------- ; This file should be linked with reqglue.o, for the SimpleRequest ;function. ;-------------------------------------------------------- SYS MACRO XREF _LVO\1 JSR _LVO\1(A6) ENDM ;-------------------------------------------------------- _main OpenReq mystart MOVE.L A6,A5 MOVE.L A6,_ReqBase PEA string MOVE.L #$C0FFEE,-(SP) MOVE.W #$1CE,-(SP) MOVE.W #'B',-(SP) MOVE.L #-12345,-(SP) MOVE.L SP,A1 LEA Text,A0 JSR SimpleRequest LEA 16(SP),SP MOVE.L A5,A1 MOVE.L 4,A6 SYS CloseLibrary MOVEQ #0,D0 RTS string DC.B "This is a string.",0 Text DC.B "A long (signed) decimal is: %ld,",10 DC.B "a character is: %c,",10 DC.B "a 16 bit hex val might be: %x, ",10 DC.B "a register-style format 32 bit hex: $%08lx,",10 DC.B "and a string might read: `%s'.",0 dseg _ReqBase DC.L 0 ;The SimpleRequest function in the glue code ;needs this variable. END ;-------------------------------------------------------------------- ;-----CUT HERE---------------CUT HERE-------------------------------- ;-------------------------------------------------------------------- ;-------------------------------------------------------------------- TwoGadRequest NAME TwoGadRequest - bring up a text requester and wait for the user to acknowledge it. SYNPOSIS result = TwoGadRequest(string, parameterlist, , ,) A0 A1 FUNCTION Bring up a requester (actually a window) containing a message to the user and wait for the user to click on either the OK or the CANCEL gadget. The window automatically sizes to fit the text and printf() style formatting can be used by TextRequest() to generate the message to the user. INPUTS string - a null terminated string, containing printf() style formatting commands if desired. parameterlist - the parameters corresponding to the printf() style formatting commands in the string. In C these are listed after the control string, exactly as with printf(). In assembler, the address of the list of parameters is put in A1. RESULT Either one or zero is returned, depending on whether the user selected, respectively, the OK or the CANCEL gadget. BUGS See TextRequest SEE ALSO TextRequest SimpleRequest This function was designed to make it as easy to give messages to the user and get a response in an intuition style requester as it is using printf() and getc(). Simply replace almost any call to printf() with a call to SimpleRequest and a requester will appear and not disappear until the user responds to it (either with a keystroke or with the mouse). Example: if (TwoGadRequest("There have %d changes made to this file.\n" "O.K. to continue?", numchanges)) exit(10); Please see the TextRequest documentation for further important details. This routine is simply a few lines of assembler glue code for the TextRequest routine. The TextRequest routine is a little bit more complicated to use, but it allows correspondingly more flexibility. It is fairly simple to modify the glue code to allow still more high level entry points to the TextRequest routine. ------------------------------------------------------------------- NAME GetString BOOL = GetString(buffer, title, window, visiblechars, maxchars) D0 A0 A1 A2 D0 D1 DESCRIPTION This routine allows you to bring up a nice intuition style string requester in its own window and get a single line of input from the user in just a one line function call. buffer points to the a buffer containing the string which will appear when the string gadget first appears and it is also where the result will be put, if this routine returns TRUE. Title is a pointer to a null terminated string that will be used for the window title. Window can be used to specify what screen you would like the requester to appear on. You simply put a window pointer in it (or a zero if you want the requester to appear on the workbench screen). If you have already set your pr_WindowPtr then you can simply pass a zero for the window pointer and the pr_WindowPtr value will be used. visiblechars specifies how many characters should actually be visible at one time. maxchars specifies how long the buffer is, including the terminating zero. RETURNS This routine returns true or false, depending on whether the user clicked on the cancel gadget (FALSE) or clicked on the OK gadget (TRUE) or clicked on the close window gadget (FALSE) or hit return in the string gadget (TRUE). BUGS None known. ------------------------------------------------------------------- NAME GetLong BOOL = GetLong(&GetLongStruct) D0 A0 DESCRIPTION This routine allows you to bring up a nice intuition style string requester in its own window and get a single signed thirty-two bit number from the user in just a one line function call (although a few fields in the structure must be initialized first). The GetLongStruct contains fields for letting you specify the title bar message, the default value that should appear in the requester and the maximum and minimum values that the routine should allow to be entered. If the routine returns TRUE (indicating successful entry of a number) then the result is returned in the result field of the structure. The window field can be used to specify what screen you would like the requester to appear on. You simply put a window pointer in it (or a zero if you want the requester to appear on the workbench screen). If you have already set your pr_WindowPtr then you can simply leave the window field zeor and the pr_WindowPtr value will be used. RETURNS This routine returns TRUE or FALSE (1 or 0) in D0 to specify whether or not the user successfully entered a number. If this routine returns TRUE then you can find the result in the result field of the GetLongStruct whose address you passed to GetLong. ------------------------------------------------------------------- RawKeyToAscii SYNOPSIS key = RawKeyToAscii(Code,Qualifier,IAddress) D0 D0 D1 A0 UWORD Code,Qualifier; APTR IAddress; FUNCTION Have you ever wanted to have both RAW and COOKED keys? You can do it by checking the keys for whatever raw keys you want, and then using the console.device's RawKeyConvert routine, except that it's a hassle to start mucking about with the device. Well, here you go! A nice, clean way of converting from a raw key to a cooked key, in a single call! All you have to do is pass the code and qualifier from your intuimessage, and the address of the message itself, and you will get back the ASCII value of the key that was hit. This does, in fact, use the console.device's RawKeyConvert, so that if you have a different keymap set, it will be used. EXAMPLE struct IntuiMessage *im; key = RawKeyToAscii(im->Code,im->Qualifier,im->IAddress);