ndow several times, it will look something like Figure 2. Theonly way to make the old imagery go away is to refresh the cardwith a GotoCard command. But this creates another problem. Thewindow snaps back to its original design size rather than thesize you selected. The same thing happens if you move the windowto a new position and then refresh the card. You could try savingthe current position (WindowX and WindowY system variables) andsize (WindowWidth and WindowHeight system variables) of thewindow in the OnResized script, reactivating the card, and thenpositioning and sizing the window in the card's AfterAttachmentscript using the MoveWindow and ResizeWindow commands. However,the ResizeWindow command causes the OnResized script to execute,which in turn reactivates the card, and so on forever. This meansflag variables have to be used. I tried several ways toaccomplish this and was never successful. In addition to the text button position problem, how do yougo about resizing the memo object when the window is resized?After all, you are probably resizing the window so you can seemore text in the memo field. CanDo only allows you to set thesize of an object at design time. This information resides in thedefinition area of an object. The solution to all the above problems is to use variablesfor the window's position and size, the text button's position,and the memo object's size. This is allowed by AV1 but cannot bedone within the CanDo programming environment.How Does CDADETextReader Work? Look at the definition sections of the window, button, andmemo object in Listing 3. The variable names used for thewindow's origin are WX and WY. The window's width and height arestored in WW and WH. The button's X and Y positions usecalculated quantities involving the system variables WindowWidthand WindowHeight. The same is true for the memo object's size.Since all the variables representing the window's position andsize have an initial value of zero, they must be assignedappropriate values before the window is displayed. The card'sBeforeAttachment script executes before the window is displayedand is the ideal place to make the assignments. However, theassignments should only be made once to prevent the window fromjumping back to its original position and size whenever the cardis reactivated. Thus, the assignments are only made whenInvocation is equal to zero. Afterwards, Invocation is assigned avalue of one to prevent the assignments from being made again.Remember this littl SSIWk. It FORM ë≡ILBMBMHD α
