I know how to create an NSImage depicting an NSView and all its subviews, but what I'm after is an NSImage of a view ignoring its subviews. I can think of ways of doing this with a subclass of NSView, but I'm keen to avoid subclassing if possible. Does anyone have any ideas?
Hide the subviews, grab the image, unhide the subviews:
NSMutableArray* hiddenViews = [[NSMutableArray] alloc init];
for (NSView* subview in [self subviews]) {
if (subview hidden) [hiddenViews addObject: subview];
else [subview setHidden:YES];
}
NSSize imgSize = self.bounds.size;
NSBitmapImageRep * bir = [self bitmapImageRepForCachingDisplayInRect:[self bounds]];
[bir setSize:imgSize];
[self cacheDisplayInRect:[self bounds] toBitmapImageRep:bir];
NSImage* image = [[NSImage alloc] initWithSize:imgSize];
[image addRepresentation:bir];
for (NSView* subview in [self subviews]) {
if (![hiddenViews containsObject: subview])
[subview setHidden:NO];
}
I would suggest making a copy of the desired NSView offscreen and taking a snapshot of that.
Related
_mainView = [[_window contentView] retain];
...
[_window release];
_window = nil;
return _mainView;
I meet code snippet above, I want to know what effects it really makes.
Thx.
Now you are the owner of highest accessible NSView object in the window’s view hierarchy.
NSView *mainView = [[window1 contentView] retain];
[window1 release];
window1 = nil;
[window setContentView:mainView];
I'm working at a custom Window object that is displayed as child in a parent Window.
For this object I'd like to create an animation like that of an NSPopover.
My first idea is to create a Screenshot of the child Window, than animate it using Core Animation and finally showing the real Window.
Before begging the implementation I would like to know if exists a better method and what you think about my solution.
It's not trivial. Here's how I do it:
#interface ZoomWindow : NSWindow
{
CGFloat animationTimeMultiplier;
}
#property (nonatomic, readwrite, assign) CGFloat animationTimeMultiplier;
#end
#implementation ZoomWindow
#synthesize animationTimeMultiplier;
- (NSTimeInterval)animationResizeTime: (NSRect)newWindowFrame
{
float multiplier = animationTimeMultiplier;
if (([[NSApp currentEvent] modifierFlags] & NSShiftKeyMask) != 0) {
multiplier *= 10;
}
return [super animationResizeTime: newWindowFrame] * multiplier;
}
#end
#implementation NSWindow (PecuniaAdditions)
- (ZoomWindow*)createZoomWindowWithRect: (NSRect)rect
{
// Code mostly from http://www.noodlesoft.com/blog/2007/06/30/animation-in-the-time-of-tiger-part-1/
// Copyright 2007 Noodlesoft, L.L.C.. All rights reserved.
// The code is provided under the MIT license.
// The code has been extended to support layer-backed views. However, only the top view is
// considered here. The code might not produce the desired output if only a subview has its layer
// set. So better set it on the top view (which should cover most cases).
NSImageView *imageView;
NSImage *image;
NSRect frame;
BOOL isOneShot;
frame = [self frame];
isOneShot = [self isOneShot];
if (isOneShot) {
[self setOneShot: NO];
}
BOOL hasLayer = [[self contentView] wantsLayer];
if ([self windowNumber] <= 0) // <= 0 if hidden
{
// We need to temporarily switch off the backing layer of the content view or we get
// context errors on the second or following runs of this code.
[[self contentView] setWantsLayer: NO];
// Force window device. Kinda crufty but I don't see a visible flash
// when doing this. May be a timing thing wrt the vertical refresh.
[self orderBack: self];
[self orderOut: self];
[[self contentView] setWantsLayer: hasLayer];
}
// Capture the window into an off-screen bitmap.
image = [[NSImage alloc] initWithSize: frame.size];
[[self contentView] lockFocus];
NSBitmapImageRep* rep = [[NSBitmapImageRep alloc] initWithFocusedViewRect: NSMakeRect(0.0, 0.0, frame.size.width, frame.size.height)];
[[self contentView] unlockFocus];
[image addRepresentation: rep];
// If the content view is layer-backed the above initWithFocusedViewRect call won't get the content
// of the view (seems it doesn't work for CALayers). So we need a second call that captures the
// CALayer content and copies it over the captured image (compositing so the window frame and its content).
if (hasLayer)
{
NSRect contentFrame = [[self contentView] bounds];
int bitmapBytesPerRow = 4 * contentFrame.size.width;
CGColorSpaceRef colorSpace = CGColorSpaceCreateWithName(kCGColorSpaceSRGB);
CGContextRef context = CGBitmapContextCreate (NULL,
contentFrame.size.width,
contentFrame.size.height,
8,
bitmapBytesPerRow,
colorSpace,
kCGImageAlphaPremultipliedLast);
CGColorSpaceRelease(colorSpace);
[[[self contentView] layer] renderInContext: context];
CGImageRef img = CGBitmapContextCreateImage(context);
CFRelease(context);
NSImage *subImage = [[NSImage alloc] initWithCGImage: img size: contentFrame.size];
CFRelease(img);
[image lockFocus];
[subImage drawAtPoint: NSMakePoint(0, 0)
fromRect: NSMakeRect(0, 0, contentFrame.size.width, contentFrame.size.height)
operation: NSCompositeCopy
fraction: 1];
[image unlockFocus];
}
ZoomWindow *zoomWindow = [[ZoomWindow alloc] initWithContentRect: rect
styleMask: NSBorderlessWindowMask
backing: NSBackingStoreBuffered
defer: NO];
zoomWindow.animationTimeMultiplier = 0.3;
[zoomWindow setBackgroundColor: [NSColor colorWithDeviceWhite: 0.0 alpha: 0.0]];
[zoomWindow setHasShadow: [self hasShadow]];
[zoomWindow setLevel: [self level]];
[zoomWindow setOpaque: NO];
[zoomWindow setReleasedWhenClosed: NO];
[zoomWindow useOptimizedDrawing: YES];
imageView = [[NSImageView alloc] initWithFrame: [zoomWindow contentRectForFrameRect: frame]];
[imageView setImage: image];
[imageView setImageFrameStyle: NSImageFrameNone];
[imageView setImageScaling: NSScaleToFit];
[imageView setAutoresizingMask: NSViewWidthSizable | NSViewHeightSizable];
[zoomWindow setContentView: imageView];
[self setOneShot: isOneShot];
return zoomWindow;
}
- (void)fadeIn
{
[self setAlphaValue: 0.f];
[self orderFront: nil];
[NSAnimationContext beginGrouping];
[[NSAnimationContext currentContext] setDuration: 0.3];
[[self animator] setAlphaValue: 1.f];
[NSAnimationContext endGrouping];
}
- (void)zoomInWithOvershot: (NSRect)overshotFrame withFade: (BOOL)fade makeKey: (BOOL)makeKey
{
[self setAlphaValue: 0];
NSRect frame = [self frame];
ZoomWindow *zoomWindow = [self createZoomWindowWithRect: frame];
zoomWindow.alphaValue = 0;
[zoomWindow orderFront: self];
NSDictionary *windowResize = #{NSViewAnimationTargetKey: zoomWindow,
NSViewAnimationEndFrameKey: [NSValue valueWithRect: overshotFrame],
NSViewAnimationEffectKey: NSViewAnimationFadeInEffect};
NSArray *animations = #[windowResize];
NSViewAnimation *animation = [[NSViewAnimation alloc] initWithViewAnimations: animations];
[animation setAnimationBlockingMode: NSAnimationBlocking];
[animation setAnimationCurve: NSAnimationEaseIn];
[animation setDuration: 0.2];
[animation startAnimation];
zoomWindow.animationTimeMultiplier = 0.5;
[zoomWindow setFrame: frame display: YES animate: YES];
[self setAlphaValue: 1];
if (makeKey) {
[self makeKeyAndOrderFront: self];
} else {
[self orderFront: self];
}
[zoomWindow close];
}
This is implemented in an NSWindow category. So you can call:
- (void)zoomInWithOvershot: (NSRect)overshotFrame withFade: (BOOL)fade makeKey: (BOOL)makeKey
on any NSWindow.
I should add that I haven't been able to get both animations to run at the same time (fade and size), but the effect is quite similar to how NSPopover does it. Maybe someone else can fix the animation issue.
Needless to say this code works on 10.6 too where you don't have NSPopover (that's why I have written it in the first place).
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 subclass NSScroller in order to draw my own scroller knob. To do this, I've subclassex NSScrollView and usex the following code to instantiate my custom NSScrollers:
- (void)awakeFromNib;
{
NSRect horizontalScrollerFrame = [[self horizontalScroller] frame];
NSRect verticalScrollerFrame = [[self verticalScroller] frame];
NSString *scrollBarVariant = [[[NSUserDefaults standardUserDefaults] persistentDomainForName:NSGlobalDomain] valueForKey:#"AppleScrollBarVariant"];
if (![scrollBarVariant isEqualToString:#"DoubleBoth"]) {
[self setVerticalScroller:[[[TRScroller alloc] initWithFrame:verticalScrollerFrame] autorelease]];
[self setHorizontalScroller:[[[TRScroller alloc] initWithFrame:horizontalScrollerFrame] autorelease]];
}
}
This works and my NSScrollers display correctly. But I'm occasionally seeing rendering issues upon first loading my application. Within Interface Builder I have laid out a number of NSScrollViews with their scrollbars set to hide automatically. The issue I'm seeing is that when the application first loads, the scrollbar backgrounds are rendered across the NSScrollViews contents.
alt text http://www.freeimagehosting.net/uploads/1d3fc75db8.png
I believe this is because I instantiate my NSScroll subclass (TRSubclass) via awakeFromNib, which means that the scrollbars are given the frame of the NSScrollView before it is automatically resized to meet the windows saved location and size (in other words, it's using the frame that's assigned by default within Interface Builder). What's the best way around this?
I've tried forcing the NSScrollView to redisplay (using setNeedsDisplay: and display:) but with no luck. Has anyone else come across a similar issue?
I'm using the same schema in my applications and I fighted this issues a lot. I use the same trick: scrollers are substituted in [scrollView awakeFromNib] methods, but I don't face such rendering issues at the moment. You can try to play with "draws background" property of the NSScrollView - it really helps sometimes
- (void)changeSubs
{
// change clip view
// ...
// change scrollers
NSRect horizontalScrollerFrame = [[self horizontalScroller] frame];
NSRect verticalScrollerFrame = [[self verticalScroller] frame];
if (![[self verticalScroller] isKindOfClass:[CRScroller class]])
[self setVerticalScroller:[[[CRScroller alloc] initWithFrame:verticalScrollerFrame] autorelease]];
if (![[self horizontalScroller] isKindOfClass:[CRScroller class]])
[self setHorizontalScroller:[[[CRScroller alloc] initWithFrame:horizontalScrollerFrame] autorelease]];
}
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self)
{
[self changeSubs];
}
return self;
}
- (id)initWithCoder:(NSCoder *)aDecoder
{
NSKeyedUnarchiver* unpacker = (id)aDecoder;
[unpacker setClass:[CRClipView class] forClassName:[NSClipView className]];
[unpacker setClass:[CRScroller class] forClassName:[NSScroller className]];
self = [super initWithCoder:aDecoder];
if (self)
{
}
return self;
}
- (void)awakeFromNib
{
[self changeSubs];
}
There are few tricks here, they work depending on a way NSScrollView is created. 'isKindOfClass' check helps to avoid double-swap.
I want to switch the image shown in an NSImageView, but I want to animate that change. I've tried various methods to do this. Hopefully one of you could suggest one that might actually work. I'm working with Cocoa for Mac.
As far as I know, NSImageView doesn't support animating image changes. However, you can place a second NSImageView on top of the first one and animate hiding the old one and showing the new one. For example:
NSImageView *newImageView = [[NSImageView alloc] initWithFrame: [imageView frame]];
[newImageView setImageFrameStyle: [imageView imageFrameStyle]];
// anything else you need to copy properties from the old image view
// ...or unarchive it from a nib
[newImageView setImage: [NSImage imageNamed: #"NSAdvanced"]];
[[imageView superview] addSubview: newImageView
positioned: NSWindowAbove relativeTo: imageView];
[newImageView release];
NSDictionary *fadeIn = [NSDictionary dictionaryWithObjectsAndKeys:
newImageView, NSViewAnimationTargetKey,
NSViewAnimationFadeInEffect, NSViewAnimationEffectKey,
nil];
NSDictionary *fadeOut = [NSDictionary dictionaryWithObjectsAndKeys:
imageView, NSViewAnimationTargetKey,
NSViewAnimationFadeOutEffect, NSViewAnimationEffectKey,
nil];
NSViewAnimation *animation = [[NSViewAnimation alloc] initWithViewAnimations:
[NSArray arrayWithObjects: fadeOut, fadeIn, nil]];
[animation setAnimationBlockingMode: NSAnimationBlocking];
[animation setDuration: 2.0];
[animation setAnimationCurve: NSAnimationEaseInOut];
[animation startAnimation];
[imageView removeFromSuperview];
imageView = newImageView;
[animation release];
If your view is big and you can require 10.5+, then you could do the same thing with Core Animation, which will be hardware accelerated and use a lot less CPU.
After creating newImageView, do something like:
[newImageView setAlphaValue: 0];
[newImageView setWantsLayer: YES];
// ...
[self performSelector: #selector(animateNewImageView:) withObject: newImageView afterDelay: 0];
- (void)animateNewImageView:(NSImageView *)newImageView;
{
[NSAnimationContext beginGrouping];
[[NSAnimationContext currentContext] setDuration: 2];
[[newImageView animator] setAlphaValue: 1];
[[imageView animator] setAlphaValue: 0];
[NSAnimationContext endGrouping];
}
You'll need to modify the above to be abortable, but I'm not going to write all your code for you :-)
You could implement your own custom view that uses a Core Animation CALayer to store the image. When you set the contents property of the layer, the image will automatically smoothly animate from the old image to the new one.