I want to set the NSSegmentedControl background image not the icon image.I subclass the NSSegmentedCell and rewrite the drawSegment: inFrame: withView: function.But this works bad.How can I do that?
update:
I want to set the half rect dark or light color background image.
Subclassing and overriding drawSegment: inFrame: withView works fine
- (void)drawSegment:(NSInteger)segment inFrame:(NSRect)frame withView:(NSView *)controlView
{
NSImage* image = [NSImage imageNamed:NSImageNameBonjour];
[image drawInRect:frame fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1.0];
[super drawSegment:segment inFrame:frame withView:controlView];
}
What else did you try?
Did you set the cell class for your segmented control correctly in Interface Builder?
Related
I am writing an app and I want to make a textfield background turn white.
So far this is my code:
- (void)viewDidLoad
{
UITextField *txtfield = UsernameTextField;
[txtfield setBackgroundColor:[UIColor colorWithWhite:1 alpha:0.5] ];
txtfield.layer.borderColor = [UIColor blackColor].CGColor;
txtfield.layer.borderWidth = 1;
txtfield.borderStyle = UITextBorderStyleRoundedRect;
[super viewDidLoad];
// Do any additional setup after loading the view.
}
But this code have a result like this:
and i tried this code , to increast alpha
[txtfield setBackgroundColor:[UIColor colorWithWhite:1 alpha:0.8] ];
still the same
and also i see this post
iPhone UITextField background color
and i tried
but it still the same
Why textfield wont turn to white?
First thing first you should
[super viewDidLoad] should be the first statement in - (void)viewDidLoad after initialising parent child should do initialise.
Second
Please check the order of views put on view controller bring UsernameTextField to top of all views or you can call [self.view bringSubviewToFront:txtfield] in code
Third
Only by setting alpha to 1.0 you can see complete white background.
and finally is you still don't get it resolved then there is some changes you did in xib/storyboard view. So to reset just delete textfield and add it again.
In order to change background color it's important to set the border to None
txtfield.borderStyle = UITextBorderStyleNone;
Details: Changing background colour within a TextField in Interface Builder
iPhone UITextField background color
From Apple Doc:
When set, the image referred to by this property replaces the standard appearance controlled by the borderStyle property. Background images are drawn in the border rectangle portion of the text field. Images you use for the text field’s background should be able to stretch to fit.
I'm trying to create a custom NSButton with a 50% opaque black background and white text. To do this I've subclassed NSButton and overloaded DrawRect:
- (void) drawRect:(NSRect)dirtyRect
{
[self setBordered:NO];
//REMED since it has same effect as NSRectFill below
//[[self cell] setBackgroundColor:[NSColor colorWithCalibratedRed:0 green:0 blue:0 alpha:0.2]];
NSColor* backgroundColor = [NSColor colorWithCalibratedWhite:0 alpha:0.3f];
[backgroundColor setFill];
NSRectFill(dirtyRect);
[super drawRect:dirtyRect];
}
The white text appears fine but the button's background is always 100% opaque. The alpha value is not interpreted.
Any ideas? Thanks!
The default operation of NSRectFill() is copy which is not what you want. Replace it with
NSRectFillUsingOperation(dirtyRect, NSCompositeSourceAtop);
Another solution I found was to keep my code the same but turn on the Core Animation Layer for each button in Interface Builder. I don't know enough about Core Animation Layer to know why this worked. I had previously turned CAL off because it was making my fonts look very jagged.
What is the method calling sequence of UIButton's drawing?
I have a UIButton subclass, let's call it UIMyButton. I add it to a .xib controller and give it a background image. Then in the UIMyButton.m file I override drawRect method and draw a shape.
Something like:
- (void)drawRect:(CGRect)rect {
CGContextRef c = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(c, [UIColor orangeColor].CGColor);
CGContextFillRect(c, rect);
}
The problem is that it draws the orange rectangle underneath the background image. What methods are responsible for drawing/updating background images (it updates on "tap down" for example)? How do I force the draw on top without adding an additional custom subview to the button (or is the background image a subview itself)?
I'm just trying to get a clear understanding of how the UIButton drawing sequence works.
The solution is to not use a background for the button. Instead, draw the image inside the drawRect method like so:
-(void)drawRect:(CGRect)rect
{
CGContextRef ctx=UIGraphicsGetCurrentContext();
UIImage *image = [UIImage imageNamed:#"image.jpg"];
[image drawInRect:self.bounds];
CGContextSetFillColorWithColor(c, [UIColor orangeColor].CGColor);
CGContextFillRect(c, rect);
}
in loadView method I set
self.navigationController.toolbarHidden = NO;
That will display a toolbar at the bottom of every view.
Now I want to have a custom background for every toolbar. So in app delegate I have following code:
#implementation UIToolbar(CustomImage)
-(void)drawRect:(CGRect)rect{
UIImage *image = [UIImage imageNamed:#"toolbar.png"];
[image drawInRect:self.bounds];
}
#end
but this has no effect. The color has still this standard blue color. How can I have a custom background?
I draw a background image in a view with the following code:
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CGContextSaveGState(currentContext);
UIImage *image = [UIImage imageNamed:#"background.jpg"];
[image drawAsPatternInRect:rect];
CGContextRestoreGState(currentContext);
This works well. But when I change the size of that view animated the drawn image is scaled until it get's redraw. How can I ignore this transformation during the animation?
At the moment I don't think that's possible. Since the iPhone doesn't have a very fast processor Apple choose to disable the LiveRedraw-feature (that actually is available on Mac).
Try setting the view's contentMode to UIViewContentModeRedraw.
- (id)initWithFrame:(CGRect)frame {
if ((self = [super initWithFrame:frame])) {
// Get the view to redraw when it's frame is changed
self.contentMode = UIViewContentModeRedraw;
}
return self;
}
I finally found a solution. I use contentMode UIViewContentModeTopLeft so it doesn't get scaled. And before the resize animation I only redraw if the new size is greater then the old one. And after the animation I always redraw.