Question

How can I update NSCursor whenever I need? I implemented resetCursorRects method. In resetCursorRects I create image with needed size (size depends on slider value in my app) and make cursor with that image. So if my slider, witch declares needed cursor size, is being changed, I need my cursor to be updated. So if thinking logically, calling [self resetCursorRects] should work, but it doesn’t. After changing slider value and for example resizing window, cursor updates. But why it doesn’t updates when I try to call it?

Answer 1

For this purpose you should implement

@property (nonatomic, retain) NSArray *cursors;

in your .h file and something like:

- (void)loadCursors
{
    NSCursor *defaultCursor = [[NSCursor alloc] initWithImage:[NSImage imageNamed:DEFAULT_CURSOR] hotSpot:NSMakePoint(2, 0)];
    NSAssert(defaultCursor, @"defaultCursor failed to load");
    NSCursor *clickedCursor = [[NSCursor alloc] initWithImage:[NSImage imageNamed:CLICKED_CURSOR] hotSpot:NSMakePoint(2, 0)];
    NSAssert(clickedCursor, @"clickedCursor failed to load");
    NSCursor *draggingCursor = [[NSCursor alloc] initWithImage:[NSImage imageNamed:DRAGGING_CURSOR] hotSpot:NSMakePoint(17, 2)];
    NSAssert(draggingCursor, @"draggingCursor failed to load");

    self.cursors = [NSArray arrayWithObjects:defaultCursor, clickedCursor, draggingCursor, nil];

    [defaultCursor release];
    [clickedCursor release];
    [draggingCursor release];

    [self resetCursorRects];
}

- (void)setCursor:(NSUInteger)cursorIndex
{
    [self discardCursorRects];

    [self addCursorRect:self.bounds cursor:[self.cursors objectAtIndex:cursorIndex]];
    [(NSCursor *)([self.cursors objectAtIndex:cursorIndex]) set];
}

- (void)resetCursorRects
{
    [self setCursor:CursorTypeDefault];
}

and use these methods in something like:

- (void)mouseDown:(NSEvent *)theEvent
{    
    [self setCursor:CursorTypeClicked];
}

or wherever you want.

Don’t forget to implement Enum with your cursor and to load cursors in your init method!

Hope this helps.