NSView drawRect interfering with subviews?
I have an nsview and i use draw rect to draw an image for background. It also has 3 subviews nsbuttons. 开发者_StackOverflow中文版The problem is, whenever the mouse is down on a button, the other buttons disappear. But when I remove the draw rect method, this doesn't happen. So I am guessing this has to do with the draw rect method for drawing images.
How can I avoid this? Thanks.
EDIT: Ok, i figured out where the problem is. Basically, I have an NSMenuItem, and I am putting a view inside it with 3 buttons. But in NSMenu, at the top, there's a padding of 4 pixels. So, basically, to remove that padding I used the solution provided here: Gap above NSMenuItem custom view
From the solution there's a line in the drawRect method:
[[NSBezierPath bezierPathWithRect:fullBounds] setClip];
The moment, i remove this line, and the button behave properly. But then, the padding on top doesn't go away.
Here's my drawRect:
- (void) drawRect:(NSRect)dirtyRect {
[[NSGraphicsContext currentContext] saveGraphicsState];
NSRect fullBounds = [self bounds];
fullBounds.size.height += 4;
[[NSBezierPath bezierPathWithRect:fullBounds] setClip];
NSImage *background = [NSImage imageNamed:@"bg.png"];
[background drawInRect:fullBounds fromRect:NSZeroRect operation:NSCompositeCopy fraction:100.0];
[[NSGraphicsContext currentContext] restoreGraphicsState];
}
The solution to the linked question doesn't include saving and restoring the graphics state, which is a good idea when you are modifying one that you didn't create. Give this a try:
- (void)drawRect:(NSRect)dirtyRect {
// Save the current clip rect that has been set up for you
[NSGraphicsContext saveGraphicsState];
// Calculate your fullBounds rect
// ...
// Set the clip rect
// ...
// Do your drawing
// ...
// Restore the correct clip rect
[NSGraphicsContext restoreGraphicsState]
Are you sure that those buttons are actually subviews, and not just placed over the view you're drawing?
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