I have a window which has a custom NSView and has a bottom bar with controls on it, one of which is an NSColorWheel.
For simplicity sake the Window is 332px high, with the custom NSView being 300px high and the bottom bar being 32px high.
The bottom bar is created as part of my awakeFromNib when the app loads the window using the following code:
[[self window] setAutorecalculatesContentBorderThickness:YES forEdge:NSMinYEdge];
[[self window] setContentBorderThickness: 32.0 forEdge: NSMinYEdge];
In my custom NSView class I fill the rectangle with color. Everything works fine when the app loads using the following in my NSView class:
- (void)drawRect:(NSRect)dirtyRect
{
dirtyRect = [self bounds];
NSColor * mNewColor = [NSColor blackColor];
[mNewColor set];
[NSBezierPath fillRect:dirtyRect];
}
However, if I subsequently call a method that changes the color of the custom NSView when a color wheel in the bottom bar is changed, the bottom bar gets overwritten with the color. The following code illustrates this method (this code is in the custom NSView class:
- (void)changeBackgroundColor:(NSNotification *)notification
{
NSLog(#"Changed background color");
NSRect mRect = [self bounds];
NSColor * mNewColor = [theColorWell color];
[mNewColor set];
[NSBezierPath fillRect:mRect];
[self setNeedsDisplay:YES];
}
Resizing the window instantly corrects the problem, but obviously I don't want the user to have to resize the window for an obvious bug!
What I don't understand is why my bounds appear to be mapping to the parent window and not the custom NSView when I call setNeedsDisplay and yet the bound correctly adjust when I resize the window using the mouse (even if just by 1 pixel).
Do I somehow need to account for the bottom bar on the redraw?
Any and all help much appreciated.
You should do all your drawing in the drawRect: method of your custom NSView. Cocoa automatically sets up the graphics context for you when it calls this method - things may not draw correctly if you perform drawing operations in other methods.
Your code in drawRect: could set the colour to the the current background colour as specified by your NSColorWell and fill the dirtyRect rectangle with this.
Then in the other method just call [self setNeedsDisplay:YES]; and then drawRect: will automatically be called to redraw the view.
See here for more information: http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/CocoaViewsGuide/SubclassingNSView/SubclassingNSView.html#//apple_ref/doc/uid/TP40002978-CH7-SW4 (in particular the Drawing View Content section)
Related
I have NSScrollView with drawable content.
It works fine with scrolling until I press Cmd+Tab or hide window in any other way.
When I open window with scrollView second time it doesn't redraw content on scrolling.
so drawRect function for documentView doesn't work anymore.
setting content view (I need to redraw it on scrolling because self.documentView is much wider than window's width)
[self.documentScroll setDocumentView:self.documentView];
in NSClipView
-(void) drawRect:(NSRect)dirtyRect {
[self setCopiesOnScroll: NO];
[super drawRect:dirtyRect];
NSArray* ar = self.subviews;
NSView* docView = ar.firstObject;
BOOL b = docView.needsDisplay;
}
docView.needsDisplay is always NO after window was hidden and shown second time. On application's launch it's always YES and drawRect method calls for documentView on every scrolling event
I have a Mac OS X (10.9) application with a custom NSView for my main NSWindow's contentView property. The only thing the custom view does is override drawRect: so that it's transparent. Transparency is required so that my NSOpenGLView is visible (see below):
/* Transparent NSView Subclass */
- (void)drawRect:(NSRect)dirtyRect
{
NSLog(#"Drawing Rect");
[[NSColor clearColor] set];
NSRectFillUsingOperation(dirtyRect, NSCompositeClear);
}
The contentView has an NSOpenGLView as a subview, with its surface order set to -1 (it's 'below' the main NSWindow, which is also transparent):
/* NSOpenGLView subclass: */
GLint order = -1;
[self.openGLContext setValues:&order forParameter:NSOpenGLCPSurfaceOrder];
I then instantiate a WebView and place it as a subview of this custom view:
_webview = [[WebView alloc] initWithFrame:frame];
[_webview setMaintainsBackForwardList:NO];
[_webview setTranslatesAutoresizingMaskIntoConstraints:NO];
[_webview setDrawsBackground:NO];
[_window.contentView addSubview:_webview];
The WebView is a small box in the window (on top of the NSOpenGLView) which is used to login to a service. Once login happens it should disappear, showing only the NSOpenGLView.
Here's the problem: when I call [_webview removeFromSuperview]; the contentView does not redraw; therefore, the WebView is still drawn on the screen (although not responsive to mouse or keyboard). If I use my mouse to resize the window that everything is in, the contentView redraws (I see the message in the logs) and the WebView's content disappears.
Also, if I don't add the NSOpenGLView as a subview, the WebView goes away as it should.
Shouldn't the contentView fire a drawRect after a subview is removed? Even when I used setNeedsDisplay: or setNeedsLayout: after removing the WebView the contentView still didn't redraw.
Apple's advice these days is to use Core Animation layers to put normal views on top of OpenGL views.
I suspect that the content view has redrawn itself. It draws clear. What you're seeing is the OpenGL surface behind it. The nearly-raw-VRAM nature of OpenGL surfaces may mean that the web view that was drawn on top of it actually modified the contents of the surface. So, I recommend that you force the OpenGL view to redraw itself. If it draws in its -drawRect:, then it should be enough to send it -setNeedsDisplay:. If you do rendering outside of -drawRect: by manually making the context current, issuing rendering commands, and then calling -flushBuffer, then you'll need to do that.
I want to change background color for many nsview. I override drawRect: on subclass NSview but i don't know how to set background color for myview( is reference IBOUTLET). please help me. Thanks so much
Code for CustomView.h
#import <Cocoa/Cocoa.h>
#interface CustomView : NSView
#end
Code for CustomView.m
#import "CustomView.h"
#implementation CustomView
- (void) drawRect:(NSRect)dirtyRect {
[[NSColor whiteColor] setFill];
NSRectFill(dirtyRect);
[super drawRect:dirtyRect];
}
#end
And in main class, i added #import "CustomView.h" but i don't know how to set background for myview.
Welcome to Cocoa drawing.
Cocoa drawing uses Quartz which is a PDF model.
Drawing in this occurs in a back to front procedural order.
In Quartz drawing there is a drawing environment state object called the Graphics Context.
This is an implicit object in many of the drawing ops in AppKit.
(in Core Graphics or other APIs it could need to be explicitly called)
You tell the Graphics Context what the current color and other parameters are, then draw something, then change parameters and draw more, etc...
In AppKit, you do this by sending a message to the NSColor object, which is weird. but that's how it works.
In your drawRect: method you should call super first usually, because you probably want your drawing on top of that...
- (void) drawRect:(NSRect)dirtyRect {
[super drawRect:dirtyRect];
// This next line sets the the current fill color parameter of the Graphics Context
[[NSColor whiteColor] setFill];
// This next function fills a rect the same as dirtyRect with the current fill color of the Graphics Context.
NSRectFill(dirtyRect);
// You might want to use _bounds or self.bounds if you want to be sure to fill the entire bounds rect of the view.
}
If you want to change the color, you'll need an #property NSColor
You might need more than one for your drawing.
That allows you to set the color.
You might want the view to use KVO and observe its own color property then draw itself if the color property changes.
You could do a lot of different things to set the color. (a button or pallette elsewhere) But all of them would eventually result in sending a message to set the color of a property of your view for drawing.
Finally, if you want to update the drawing, you need to call [myView setNeedsDisplay:YES]; where myView is a reference to an instance of the NSView subclass.
There is also display but that's forceful.
setNeedsDisplay: says to schedule it on the next run of the event loop (runLoop). display kind of makes everything jump to that right away.
The event loop comes back around fast enough you shouldn't force it.
Of note, setNeedsDisplay: is the entire view.
In a fancy ideal world with complex views, you might want to more appropriately optimize things by calling setNeedsDisplayInRect: where you designate a specific CG/NSRect of the view as needing to be redrawn.
This allows the system to focus redrawing to the smallest union rect possible in the window.
I'm super late, but this is how I do it - there's no need to sub class:
NSView *myview = [NSView new];
[view setWantsLayer:YES];
view.layer.backgroundColor = [NSColor greenColor].CGColor;
I want to display NSImage as repeated background in NSWindow. I am using this code:
_window.backgroundColor = [NSColor colorWithPatternImage:[NSImage imageNamed:#"image.png"]];
The problem arises on resizing, because only the new area (at the bottom and the right) of the window is redisplayed and the background origin is in the bottom-left corner. That results in image gliching:
Current workaround is to redisplay window on resize:
_window.delegate = self;
...
- (void)windowDidResize:(NSNotification *)notification {
[_window display];
}
My questions are:
Is there a way to automatically display all background on resizing (i.e. without usign windowDidResize:)?
Can background origin be changed to upper-left correr (so that new area on resizing will seamlessly continue existing one)?
I am trying to draw an image into a UIView subclass overriding drawRect. This image drawing class needs moving and zooming capabilities, so I made it a subview of a scrollview.
My problem is that my image seems to get cropped, either by the screen or the scrollView bounds (the image is larger than the screen). I don't have a clue why, this seems to e pretty basic stuff.
The view hierarchy in my ViewController looks like this:
View Controller
View
ScrollView
MapView
I've created outlets for the scroll view and the map view (which is the view implementing drawRect).
My ViewController initial setup code for configuring the scroll view looks like this:
- (void)viewDidLoad
{
[super viewDidLoad];
scrollView.delegate = self;
scrollView.contentSize = CGSizeMake(450, 476);
scrollView.minimumZoomScale = 0.6;
scrollView.maximumZoomScale = 6.0;
}
My drawRect implementation:
- (void)drawRect:(CGRect)rect
{
UIImage *myImage = [UIImage imageNamed:#"map.jpg"];
CGRect rectangle = CGRectMake(0,0,450,476);
[myImage drawInRect:rectangle];
}
The image is draggable and zoomable within the scroll view, but it's cropped at what seems to be the screen bounds.
Any help would be appreciated.
drawRect can't draw outside the rect passed as a parameter to the drawRect method, which is determined by the view frame. Make your view 1200,1200 and make sure that clipToBounds is disabled on all the containing views.
Your problem is probably in drawInRect. From documentation of UIImage class:
drawInRect:
Draws the entire image in the specified rectangle, scaling it as needed to fit.
Make that rectangle bigger as you wish and center it in UIImageView. This question is answered here UIScrollView image/photo viewer with paging enabled and zooming