Nebula 2/Nebula Two.iso/SourceCode/Database/TableView/TableViewController.m

Text File | 1995-06-12 | 5KB | 197 lines

/* TableViewController.m:
 * You may freely copy, distribute, and reuse the code in this example.
 * NeXT disclaims any warranty of any kind, expressed or  implied, as to its
 * fitness for any particular use.
 *
 * Written by: Mai Nguyen, NeXT Developer Support
 *
 *
 */
#import "TableViewController.h"

#define INSTALL_MODEL NXLocalizedString("Please install SybaseDemo.dbmodela or OracleDemo.dbmodela in your project.", NULL, "Notify user that the ascii model files must be installed in his project directory.")

/* Comment this line out if you want to run an Oracle version */
#define    SYBASE_DEMO     1

@implementation TableViewController
/*
* Miscellaneous initialization tasks: connect to database, initialize
* tableview, set up dbModule.
*/
-appDidInit:sender
{
    NXRect viewFrame;

#ifdef SYBASE_DEMO
    /* Notify the user if the database can't be found */
    if (!(dbDatabase = [DBDatabase findDatabaseNamed:"SybaseDemo"
                    connect:YES])) {
        NXRunAlertPanel(NULL,INSTALL_MODEL, "OK", NULL, NULL);
        return self;
    }
#else
    /* Notify the user if the database can't be found */
    if (!(dbDatabase = [DBDatabase findDatabaseNamed:"OracleDemo"
                    connect:YES])) {
        NXRunAlertPanel(NULL,INSTALL_MODEL, "OK", NULL, NULL);
        return self;
    }
#endif

    [dbDatabase setDelegate:self];

        /* Install the tableview into the custom view */
    [[dbTableView getFrame:&viewFrame] free];
    dbTableView = [[DBTableView alloc] initFrame:&viewFrame];
    [[window contentView] addSubview:dbTableView];
    [dbTableView setHorizScrollerRequired:YES];
    [dbTableView setVertScrollerRequired:YES];
    [dbTableView setDelegate: self];

#ifdef SYBASE_DEMO
    rootEntity = [dbDatabase entityNamed:"Author"];
#else
    rootEntity = [dbDatabase entityNamed:"Order"];
#endif
        /* Must initialize your dbModule */
      dbModule = [[DBModule alloc] initDatabase:dbDatabase
                            entity:rootEntity];
    dbFetchGroup = [dbModule rootFetchGroup];
    [dbFetchGroup setDelegate:self];
#ifdef SYBASE_DEMO
    dbQualifier = [[DBQualifier alloc] initForEntity:[dbModule entity]
                fromDescription:"state = %s", "CA"];
#else
    dbQualifier = [[DBQualifier alloc] initForEntity:[dbModule entity]
                fromDescription:"customer.state = %s", "CA"];
#endif
    [window disableFlushWindow];
    [self initTableView];
    [[window reenableFlushWindow] flushWindow];

    return self;
}
- showAll:sender
{
    [dbFetchGroup fetchContentsOf:[dbModule entity]
                                            usingQualifier:dbQualifier];
    [dbTableView display];

    return self;
}

/* In order to replicate the Interface Builder functionality, one has to
 * add an expression to the fetchgroup for each attribute and subattribute.
 */

- addTableColumn:(const char *)label
{
    id newExpression;

    /* allocate a new expression, add it to the FetchGroup and add it */
    /* to the TableView */
    newExpression = [[DBExpression alloc] initForEntity:[dbModule entity]
                fromDescription:label];
    [dbFetchGroup addExpression:newExpression];
    [dbTableView  addColumn:newExpression withTitle:label];
    return self;
}


/* Get all the attributes and subattributes from the defined table and
 *    initialize the tableview accordingly.
 */
- initTableView
{
    int i, j, propCount, subpropCount;
    id prop, subprop, subpropList;
    char buffer[100];
    id <DBEntities, DBTypes> theEntity;

      propList = [[List alloc] init];
    [rootEntity getProperties: propList];
    propCount = [propList count];

    for (i = 0; i < propCount; i++) {
        prop = [propList objectAt:i];
        theEntity = (id<DBTypes>)[prop propertyType];
        if(! [theEntity isEntity]) {

            /* add top-level attribute */
            [self addTableColumn:[prop name]];   /* defined above */
        } else if ([prop isSingular]) {

            /* add all sub-attributes but skip sub-relationships.
               Note that getting sub-attributes only work for
               to-one relationship
             */
            subpropList  = [[List alloc] init];

            [theEntity getProperties:subpropList];
            subpropCount = [subpropList count];
            for (j = 0; j < subpropCount; j++) {
                subprop = [subpropList objectAt:j];
                if (![[subprop propertyType] isEntity]) {
                sprintf(buffer, "%s.%s", [prop name], [subprop name]);
                [self addTableColumn:buffer];   /* defined above */
                }
            }
            [subpropList free];        /* to prevent a memory leak */
        }
    }

        /* Making this association will make the fetchgroup
         * become the tableview data source.
         */
    [dbFetchGroup makeAssociationFrom:nil to:dbTableView];
        /*
         * free property list which is no longer needed
         */
    [propList free];
    [window makeKeyAndOrderFront:self];
    return self;
}


/* Set the sort order before the actual fetch */
- fetchGroupWillFetch: sender
{
    if( sortProp == nil) {
    sortProp = [[dbTableView columnAt: 0] identifier];
    }
    [[sender recordList]
    addRetrieveOrder: DB_AscendingOrder
        for: sortProp];
    return self;
}

/* Find the new sort property every time the tableView column gets moved */
- tableView:sender movedColumnFrom:(unsigned int) old to:(unsigned int) new
{
    sortProp = [[sender columnAt: new] identifier];
    return [dbModule fetchAllRecords: self];
}




- free
{
    if (dbQualifier)
        [dbQualifier free];
    if (dbTableView)
        [dbTableView free];
    return [super free];
}

/* DBDatabase delegate methods to log SQL queries  - Useful for debugging */

- (BOOL)db:aDb willEvaluateString:(const char*)aString usingBinder:aBinder
{
    fprintf(stderr, "SQL query:%s\n", aString);
    return YES;
}

@end