I am creating a NSView subclass that has rounded corners. This view is meant to be a container and other subviews will be added to it. I am trying to get the rounded corners of the NSView to clip all of the subview's corners as well, but am not able to get it.
- (void)drawRect:(NSRect)dirtyRect {
NSRect rect = [self bounds];
NSBezierPath *path = [NSBezierPath bezierPathWithRoundedRect:rect xRadius:self.radius yRadius:self.radius];
[path addClip];
[[NSColor redColor] set];
NSRectFill(dirtyRect);
[super drawRect:dirtyRect];
}
The red is just for example. If I add a subview to the rect, The corners are not clipped:
How can I achieve this?
Using Core Animation layers will clip sublayers correctly.
In your container NSView subclass:
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
self.layer = _layer; // strangely necessary
self.wantsLayer = YES;
self.layer.masksToBounds = YES;
self.layer.cornerRadius = 10.0;
}
return self;
}
You can do it in the interface builder without subclassing adding User Defined Runtime Attributes"
Have you tried clipping with layers?
self.layer.cornerRadius = self.radius;
self.layer.masksToBounds = YES;
Ah, sorry, somehow I've missed that you were talking about NSView, not UIView. It would be hard to clip NSView subviews in all cases because it seems that most of Cocoa standard views set their own clipping path. It might be easier to layout subviews with some paddings and avoid need for clipping.
Related
I am trying to make a "hole" in an NSWindow using a CAShapeLayer or even just a CALayer.
When using regular NSViews or even layer-backed views, I can override drawRect: using code like this:
[spotImage drawInRect:self.bounds fromRect:NSZeroRect operation:NSCompositeXOR fraction:1.0];
where spotImage is an NSImage with pure white content and some gradations, and the window has a black background with 0.5 alpha. The NSView subclass where this drawRect is defined has a clearColor background.
The end result is a grey window (It is a transparent window with a styleMask of NSBorderlessWindowMask as can be found in many samples.
If I turn the NSView into a layer-backed view, it calls the drawRect methods and works fine.
When I turn this into a layer-hosting view, and again use the same structure (NSWindow > contentView > CustomView) then, the drawInRect method just draws the image. It no longer punches a hole through it.
It is like the layer itself can no longer punch the hole when it is part of a layer-hosting hierarchy.
Here is some sample code:
The custom NSWindow subclass initializer:
- (id)initWithContentRect:(NSRect)contentRect styleMask:(NSUInteger)aStyle backing:(NSBackingStoreType)bufferingType defer:(BOOL)flag {
self = [super initWithContentRect:contentRect styleMask:NSBorderlessWindowMask backing:NSBackingStoreBuffered defer:NO];
if (self) {
[self setBackgroundColor: [NSColor lightGrayColor]]; //[NSColor clearColor]];
[self setAlphaValue:0.5];
[self setOpaque:NO];
[self setHasShadow: NO];
[self useOptimizedDrawing:YES];
[self setIgnoresMouseEvents:YES];
}
return self;
}
the code in my applicationDidFinishLaunching method:
PPContentView *thisView = [[PPContentView alloc]
initWithFrame:CGRectInset([self.window.contentView bounds], 50, 50)];
//[thisView setWantsLayer:YES]; enabling this makes things opaque again
[self.window.contentView addSubview:thisView];
thisView.layer.backgroundColor = [NSColor clearColor].CGColor;
//Create custom content
[thisView setNeedsDisplay:YES];
}
and my custom view's drawRect contains:
[[NSImage imageNamed:#"spotFuzzy.png"] drawInRect:self.bounds fromRect:NSZeroRect operation:NSCompositeXOR fraction:1.0];
How to shadow documentView in NSScrollView?
The effect look likes iBook Author:
You need to inset the content in your document view to allow space for the shadow to be displayed, then layer back the view and set a shadow on it. Example:
view.wantsLayer = YES;
NSShadow *shadow = [NSShadow new];
shadow.shadowColor = [NSColor blackColor]
shadow.shadowBlurRadius = 4.f;
shadow.shadowOffset = NSMakeSize(0.f, -5.f);
view.shadow = shadow;
The NSScrollView contentView is an NSView subclass, which has a shadow field, if you create a shadow object and assign it to this field, the view will automatically show a drop shadow when drawn
NSShadow* shadow = [[NSShadow alloc] init];
shadow.shadowBlurRadius = 2; //set how many pixels the shadow has
shadow.shadowOffset = NSMakeSize(2, -2); //the distance from the view the shadow is dropped
shadow.shadowColor = [NSColor blackColor];
self.scrollView.contentView.shadow = shadow;
This works because all views when are drawn on drawRect use this shadow property by using [shadow set].
doing [shadow set] during a draw operation makes whatever is drawn after that to be replicated underneath
I'm new to entering posts on stack overflow but I had the same issue and have solved it so I thought after searching the net for hours to find a solution it would be nice to answer it.
My solution is to create a subclass for NSClipView with the following code for drawRect...
- (void)drawRect:(NSRect)dirtyRect
{
[super drawRect:dirtyRect];
NSRect childRect = [[self documentView] frame];
[NSGraphicsContext saveGraphicsState];
// Create the shadow below and to the right of the shape.
NSShadow* theShadow = [[NSShadow alloc] init];
[theShadow setShadowOffset:NSMakeSize(4.0, -4.0)];
[theShadow setShadowBlurRadius:3.0];
// Use a partially transparent color for shapes that overlap.
[theShadow setShadowColor:[[NSColor grayColor]
colorWithAlphaComponent:0.95f]];
[theShadow set];
[[self backgroundColor] setFill];
NSRectFill(childRect);
// Draw your custom content here. Anything you draw
// automatically has the shadow effect applied to it.
[NSGraphicsContext restoreGraphicsState];
}
You then need to create an instance of the subclass and set it with the setContentView selector.
You also need to repaint the clip view every time the content view size changes. If you have your content view set up to change in terms of canvas size when the user wants then unless you repaint the clip view some nasty shadow marks will left behind.
You don't need to mess about with clips as others have suggested.
Hope it helps!
I'm working on a Mac application with an NSScrollView, and I want the NSScrollView to have a custom background image. I used this code in the custom documentView NSView subclass:
- (void)drawRect:(NSRect)rect {
[[NSColor colorWithPatternImage:[NSImage imageNamed:#"wood.jpg"]] set];
NSRectFill(rect);
}
That displays a pattern image as a background for the documentView.
But now in Mac OS X Lion, the NSScrollView bounces when scrolling further than possible, showing ugly white space. How can I make the white space also being covered by the background image?
Instead of overriding drawRect:, use the scroll view's setBackgroundColor: method, passing the NSColor you created with the pattern image.
You should subclass use NSScrollView setBackgroundColor, but then you should subclass NSClipView like this to pin the texture origin to the top:
#implementation MYClipView
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code here.
}
return self;
}
- (void)drawRect:(NSRect)dirtyRect
{
if (self.drawsBackground)
{
NSGraphicsContext* theContext = [NSGraphicsContext currentContext];
[theContext saveGraphicsState];
float xOffset = NSMinX([self convertRect:[self frame] toView:nil]);
float yOffset = NSMaxY([self convertRect:[self frame] toView:nil]);
[theContext setPatternPhase:NSMakePoint(xOffset, yOffset)];
NSColor* color = self.backgroundColor;
[color set];
NSRectFill([self bounds]);
[theContext restoreGraphicsState];
}
// Note: We don't call [super drawRect:dirtyRect] because we don't need it to draw over our background.
}
+ (void)replaceClipViewInScrollView:(NSScrollView*)scrollView
{
NSView* docView = [scrollView documentView]; //[[scrollView documentView] retain];
MYClipView* newClipView = nil;
newClipView = [[[self class] alloc] initWithFrame:[[scrollView contentView] frame]];
[newClipView setBackgroundColor:[[scrollView contentView] backgroundColor]];
[scrollView setContentView:(NSClipView*)newClipView]; [scrollView setDocumentView:docView];
// [newClipView release];
// [docView release];
}
#end
And call + (void)replaceClipViewInScrollView:(NSScrollView*)scrollView with the NSScrollView instance.
Put your drawRect code in an NSScrollView subclass. In IB, change the NSScrollView to use your custom subclass instead of NSScrollView. Also make sure to uncheck Draw Background in the scroll view's attributes inspector.
I'm trying to create a drop shadow surrounding the NSView like how NSWindow does it with its shadow, but I'm having some difficulty. I created a class for the NSView I'm creating the drop shadow for and I'm using this code for the overriding method:
-(void)drawRect:(NSRect)dirtyRect {
NSRect rect = NSInsetRect([self bounds], 10.0, 10.0);
NSShadow *dropShadow = [[[NSShadow alloc] init] autorelease];
[dropShadow setShadowColor:[NSColor blackColor]];
[dropShadow setShadowBlurRadius:5];
[dropShadow setShadowOffset:NSMakeSize(0,-3)];
[NSGraphicsContext saveGraphicsState];
[dropShadow set];
NSRectFill(rect);
[NSGraphicsContext restoreGraphicsState];
[super drawRect:dirtyRect];
}
This doesn't really create a drop shadow in which I'm looking.
Here is the shadow I'm trying to aim for...
rather creates a line through the NSView that seems like a border within the bounds of the view. Anyone got any ideas for this?
I have faced similar shadow issues because NSView clips its bounds.
I fixed it when I used a layer backed view. I simply set the superview's wantsLayer property to YES.. i.e [[view superView] setWantsLayer:YES] and set shadow for view [view setShadow:dropShadow].
Im working on a drag n' drop view and found some handlers for drag and drop actions on the web. I want to make it so it turns blue when the user drags a file over the drag and drop area and gray again when they exit the drag and drop area. The issues is its not updating when you drag your mouse over it or exit it. Heres some of the code:
- (void)drawRect:(NSRect)rect
{
NSRect bounds = [self bounds];
[[NSColor grayColor] set];
[NSBezierPath fillRect:bounds];
}
- (NSDragOperation)draggingEntered:(id <NSDraggingInfo>)sender {
NSRect bounds = [self bounds];
[[NSColor blueColor] set];
[NSBezierPath fillRect:bounds];
return NSDragOperationCopy;
}
- (void)draggingExited:(id <NSDraggingInfo>)sender {
NSRect bounds = [self bounds];
[[NSColor grayColor] set];
[NSBezierPath fillRect:bounds];
}
Thanks for any help.
Are you calling [yourView: setNeedsDisplay] anywhere?
This is how you let the drawing framework know it needs to message your UIView subclass with drawRect:, so you should do it whenever things have changed. In your case, this probably means when the mouse enters or exits the drop area.
Drawing only works when a context (like a canvas for painting) is set up for you to draw into. When the framework calls -drawRect: it has set up a drawing context for you, so drawing commands like -[NSColor set] and -[NSBezierPath fillRect:] work as you expect.
Outside of -drawRect: there is usually no drawing context set up. Using drawing commands outside of -drawRect: is like waving a paintbrush in the air; there's no canvas, so no painting happens.
In 99.99% of cases, all view drawing should be kept within -drawRect: because NSView does a lot of work that you don't want to do to get the drawing context set up correctly and efficiently.
So, how do you change your view's drawing within your -draggingEntered: and -draggingExited: methods? By side effects.
You're doing the same thing in all three cases: 1) Setting a color and 2) Drawing a rectangle. The only difference is the color changes in each method. So, why not control which color you use in -drawRect: with an ivar, like so:
- (void)draggingEntered:(id <NSDraggingInfo>)sender {
drawBlueColorIvar = YES;
// ...
}
Then in -drawRect: you do this:
- (void)drawRect:(NSRect)rect {
NSColor *color = drawBlueColorIvar ? [NSColor blueColor] : [NSColor grayColor];
[color set];
[NSBezierPath fillRect:rect];
}
(Notice I didn't use [self bounds]. It is more efficient to just draw into the "dirty" rect, when possible.)
Finally, you need some way to tell the framework that your view needs to redraw when drawBlueColorIvar changes. The framework won't draw anything unless it's told it needs to. As Chris Cooper said, you do this with [self setNeedsDisplay:YES]. This should go after any place you change drawBlueColorIvar.