I've built a custom IKImageBrowserCell which is displaying my images in an IKImageBrowser without any issues.
I'd like to try and override the built in IKImageBrowser delete image functionality. Currently 'out of the box' you can select an image, or multiple images and press BACKSPACE to delete.
I'd like to add an NSButton or similar to enable that same functionality on each image.
I've added the following code to show a delete icon on the IKImageBrowserCell when it is selected:
- (CALayer *) layerForType:(NSString*) type {
CGColorRef color;
//retrieve some usefull rects
NSRect frame = [self frame];
NSRect imageFrame = [self imageFrame];
NSRect relativeImageFrame = NSMakeRect(imageFrame.origin.x - frame.origin.x, imageFrame.origin.y - frame.origin.y, imageFrame.size.width, imageFrame.size.height);
if(type == IKImageBrowserCellForegroundLayer){
//no foreground layer on place holders
if([self cellState] != IKImageStateReady)
return nil;
//create a foreground layer that will contain several childs layer
CALayer *layer = [CALayer layer];
layer.frame = CGRectMake(0, 0, frame.size.width, frame.size.height);
if([self isSelected]){
//add a delete icon
CALayer *deleteLayer = [CALayer layer];
[deleteLayer setContents:(id)deleteImage()];
deleteLayer.frame = CGRectMake(relativeImageFrame.size.width-14, (relativeImageFrame.origin.y+relativeImageFrame.size.height)-14, 28, 28);
[layer addSublayer:deleteLayer];
}
}
}
This works great, but obviously just a static image. Is there any way I can try and get an event from hitting this delete icon, and then return the selected cell index to the IKImageBrowser in order to call it's removeItemsFromIndex: method ? Am stuck!
myIKImageBrowserView.selectionIndexes() returns an NSIndexSet of the currently selected cell(s) - you can use that to call the removeItemsFromIndex method just before you delete the layer
https://developer.apple.com/library/mac/documentation/GraphicsImaging/Reference/IKImageBrowserView/index.html
Related
I am developing an app that contains lots of custom NSView objects being moved around. I have implemented a gaussian blur background filter for one of the custom NSView subclasses like so:
- (id)init {
self = [super init];
if (self) {
...
CIFilter *saturationFilter = [CIFilter filterWithName:#"CIColorControls"];
[saturationFilter setDefaults];
[saturationFilter setValue:#.5 forKey:#"inputSaturation"];
CIFilter *blurFilter = [CIFilter filterWithName:#"CIGaussianBlur"];
[blurFilter setDefaults];
[blurFilter setValue:#2.0 forKey:#"inputRadius"];
self.wantsLayer = YES;
self.layer.backgroundColor = [NSColor clearColor].CGColor;
self.layer.masksToBounds = YES;
self.layer.needsDisplayOnBoundsChange = YES;
self.layerUsesCoreImageFilters = YES;
[self updateFrame]; //this is where the frame size is set
self.layer.backgroundFilters = #[saturationFilter, blurFilter];
...
return self;
}
else return nil;
}
This works great and creates a gaussian blur effect within the entire contents of the view. The problem is that I do not want the gaussian blur to cover the entire view. There is about an (intentional) 12px padding between the actual size of the NSView and the drawing of its content box:
- (void)drawRect:(NSRect)dirtyRect {
[super drawRect:dirtyRect];
NSColor* strokeColor = [NSColor colorWithRed:.5 green:.8 blue:1 alpha:1];
NSColor* fillColor = [NSColor colorWithRed:.5 green:.8 blue:1 alpha:.2];
...
[strokeColor setStroke];
[fillColor setFill];
NSBezierPath *box = [NSBezierPath bezierPathWithRoundedRect:NSMakeRect(self.bounds.origin.x + 12, self.bounds.origin.y + 12, self.bounds.size.width - 24, self.bounds.size.height - 24) xRadius:6 yRadius:6];
box.lineWidth = 6;
[box stroke];
[box fill];
...
}
The reason for this padding is that there are some pieces of the GUI that inhabit this region and are drawn seamlessly into the containing box. I would like to mask the Blur effect to only have effect on the interior of the drawn box rather than the entire view. Here is what I have tried.
ATTEMPT 1: Create a sublayer
I created a sublayer in the NSView with the appropriately sized frame, and added the blur effect to this sublayer. PROBLEM: The blur effect seems to only apply to the immediate parent layer, so rather than blur the contents behind the NSView, it blurs the contents of the NSView's self.layer (which is basically empty).
ATTEMPT 2: Create a masking layer
I tried to create a masking layer and set it to self.layer.mask. However, since the positions of the GUI content do change (via the DrawRect function), I would need to get a copy of the current layer to use as the masking layer. I tried the following code, but it had no effect.
self.layer.mask = nil;
NSArray *bgFilters = self.layer.backgroundFilters;
self.layer.backgroundFilters = nil;
CALayer *maskingLayer = self.layer.presentationLayer;
self.layer.mask = maskingLayer;
self.layer.backgroundFilters = bgFilters;
ATTEMPT 3: Draw a masking layer directly
I could not find any examples of how to draw directly on a layer. I can not use a static UIImage to mast with, because, as I said above, the mask has to change with user interaction. I was looking for something equivalent to the DrawRect function. Any help would be appreciated.
SO...
It seems to me that the sublayer way would be the best and simplest way to go, if I could just figure out how to change the priority of the blur effect to be the background behind the NSView not the NSView's background layer behind the sublayer.
Well, I would still like to know if there is a more elegant way, but I have found a solution that works. Basically, I have created a masking layer from an NSImage drawn from a modified version of the drawRect function:
- (id)init {
self = [super init];
if (self) {
// SETUP VIEW SAME AS ABOVE
CALayer *maskLayer = [CALayer layer];
maskLayer.contents = [NSImage imageWithSize:self.frame.size flipped:YES drawingHandler:^BOOL(NSRect dstRect) {
[self drawMask:self.bounds];
return YES;
}];
maskLayer.frame = self.bounds;
self.layer.mask = maskLayer;
return self;
}
else return nil;
}
- (void)drawMask:(NSRect)dirtyRect {
[[NSColor clearColor] set];
NSRectFill(self.bounds);
[[NSColor blackColor] set];
// SAME DRAWING CODE AS drawRect
// EXCEPT EVERYTHING IS SOLID BLACK (NO ALPHA TRANSPARENCY)
// AND ONLY NEED TO DRAW PARTS THAT EFFECT THE EXTERNAL BOUNDARIES
}
I have a UIButton and i want it to display a triangle. Is there a function to make it a triangle? Since im not using a UIView class im not sure how to make my frame a triangle.
ViewController(m):
- (IBAction)makeTriangle:(id)sender {
UIView *triangle=[[UIView alloc] init];
triangle.frame= CGRectMake(100, 100, 100, 100);
triangle.backgroundColor = [UIColor yellowColor];
[self.view addSubview: triangle];
Do i have to change my layer or add points and connect them to make a triangle with CGRect?
If im being unclear or not specific add a comment. Thank you!
A button is a subclass of UIView, so you can make it any shape you want using a CAShape layer. For the code below, I added a 100 x 100 point button in the storyboard, and changed its class to RDButton.
#interface RDButton ()
#property (strong,nonatomic) UIBezierPath *shape;
#end
#implementation RDButton
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self) {
self.titleEdgeInsets = UIEdgeInsetsMake(30, 0, 0, 0); // move the title down to make it look more centered
self.shape = [UIBezierPath new];
[self.shape moveToPoint:CGPointMake(0,100)];
[self.shape addLineToPoint:CGPointMake(100,100)];
[self.shape addLineToPoint:CGPointMake(50,0)];
[self.shape closePath];
CAShapeLayer *shapeLayer = [CAShapeLayer layer];
shapeLayer.path = self.shape.CGPath;
shapeLayer.fillColor = [UIColor yellowColor].CGColor;
shapeLayer.strokeColor = [UIColor blueColor].CGColor;
shapeLayer.lineWidth = 2;
[self.layer addSublayer:shapeLayer];
}
return self;
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if ([self.shape containsPoint:[touches.anyObject locationInView:self]])
[super touchesBegan:touches withEvent:event];
}
The touchesBegan:withEvent: override restricts the action of the button to touches within the triangle.
A view's frame is always a rect, which is a rectangle. Even if you apply a transform to it so it no longer looks like a rectangle, the view.frame property will still be a rectangle -- just the smallest possible rectangle that contains the new shape you have produced.
So if you want your UIButton to look like a triangle, the simplest solution is probably to set its type to UIButtonTypeCustom and then to set its image to be a png which shows a triangle and is transparent outside of the triangle.
Then the UIButton itself will actually be rectangle, but will look like a triangle.
If you want to get fancy, you can also customize touch delivery so that touches on the transparent part of the PNG are not recognized (as I believe they would be by default), but that might be a bit trickier.
I am using a mask to remove unwanted parts of an image. This all works correctly using the code below.
I then attach a tap gesture event to the image. However, I want the tap event gesture to be applied the result of the masked image rather than the full size of the UIimage frame. Any suggestions on how to do this?
CALayer *mask = [CALayer layer];
mask.contents = (id)[[UIImage imageNamed:self.graphicMask] CGImage];
mask.frame = CGRectMake(0, 0, 1024, 768);
[self.customerImage setImage:[UIImage imageNamed:self.graphicOff]];
[[self.customerImage layer] setMask:mask];
self.customerImage.layer.masksToBounds = YES;
//add event listener
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(customerSelected)];
[self.customerImage addGestureRecognizer:tap];
Update - My solution
In the end I decided not to use a mask and instead check the pixel colour of the touched point (as suggested by the correct answer). I used code from another question https://stackoverflow.com/a/3763313/196361.
I added a method to the view controller that is called whenever the view is touched.
- (void)touchesBegan:(NSSet*)touches
{
//check the colour of a touched point on the customer image
CGPoint p = [(UITouch*)[touches anyObject] locationInView:self.customerImage];
UIImage *cusUIImg = self.customerImage.image;
unsigned char pixel[1] = {0};
CGContextRef context = CGBitmapContextCreate(pixel,1, 1, 8, 1, NULL, kCGImageAlphaOnly);
UIGraphicsPushContext(context);
[cusUIImg drawAtPoint:CGPointMake(-p.x, -p.y)];
UIGraphicsPopContext();
CGContextRelease(context);
CGFloat alpha = pixel[0]/255.0;
//trigger click event for this customer if not already selected
if(alpha == 1.000000)
[self customerSelected];
}
If your mask is fairly rectangular then the easiest way would be to add transparent UIView on top with frame matching the masked region. Then you would add UITapGestureRecognizer directly to the invisible view.
EDIT
If you want your taps to be accepted based on the mask exactly then you can read the pixel color of mask in the tap location and check against your threshold.
I use a CALayer and CATextLayers to lay out the numbers on a sudoku grid on the iPhone.
I have a tableView that lists some sudokus. When I tap one table cell it shows the sudoku in another viewController that is pushed on to the navigation controller.
In my - (void)viewWillAppear... method I call my - (void)loadSudoku method which I will show you below.
The problem is when you look at one sudoku, go back to the table view using the "back" button in the navigationBar and then tap another sudoku. Then the old sudoku is still there, and the new one is drawn on top of the old one.
I guess I need to clear the old one somehow. Any ideas?
I do have a background image set through the interface builder of the actual sudoku grid. I don't want to remove this.
The method that draws the sudoku looks like this:
- (void)loadSudoku
{
mainLayer = [[self view] layer];
[mainLayer setRasterizationScale:[[UIScreen mainScreen] scale]];
int col=0;
int row=0;
for(NSNumber *nr in [[self sudoku] sudoku])
{
if([nr intValue] != 0)
{
//Print numbers on grid
CATextLayer *messageLayer = [CATextLayer layer];
[messageLayer setForegroundColor:[[UIColor blackColor] CGColor]];
[messageLayer setContentsScale:[[UIScreen mainScreen] scale]];
[messageLayer setFrame:CGRectMake(col*36+5, row*42, 30, 30)];
[messageLayer setString:(id)[nr stringValue]];
[mainLayer addSublayer:messageLayer];
}
if(col==8)
{
col=0; row++;
}else
{
col++;
}
}
[mainLayer setShouldRasterize:YES];
}
To remove only text layers, you can do this –
NSIndexSet *indexSet = [mainLayer.sublayers indexesOfObjectsPassingTest:^(id obj, NSUInteger idx, BOOL *stop){
return [obj isMemberOfClass:[CATextLayer class]];
}];
NSArray *textLayers = [mainLayer.sublayers objectsAtIndexes:indexSet];
for (CATextLayer *textLayer in textLayers) {
[textLayer removeFromSuperlayer];
}
In a nutshell, the first statement gets all the indices of text layers which are a sublayer to over root layer. Then in the second statement we get all those layers in a separate array and then we remove them from their superlayer which is our root layer.
Original Answer
Try doing this,
mainLayer.sublayers = nil;
I am adding two CAText layers to a view and animating one of them. I want to animate one layer above the other but it doesn't get positioned correctly in the layer hierarchy until the animation has finished. Can anyone see what I have done wrong? The animation works, it is just running behind 'topcharlayer2' until the animation has finished.
- (CABasicAnimation *)topCharFlap
{
CABasicAnimation *flipAnimation;
flipAnimation = [CABasicAnimation animationWithKeyPath:#"transform"];
flipAnimation.toValue = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(1.57f, 1, 0, 0)];
flipAnimation.fromValue = [NSValue valueWithCATransform3D:CATransform3DMakeRotation(0.0, 1, 0, 0)];
flipAnimation.autoreverses = NO;
flipAnimation.duration = 0.5f;
flipAnimation.repeatCount = 10;
return flipAnimation;
}
- (id)initWithFrame:(CGRect)frame {
if ((self = [super initWithFrame:frame])) {
[self setBackgroundColor:[UIColor clearColor]]; //makes this view transparent other than what is drawn.
[self initChar];
}
return self;
}
static CATransform3D CATransform3DMakePerspective(CGFloat z)
{
CATransform3D t = CATransform3DIdentity;
t.m34 = - 1. / z;
return t;
}
-(void) initChar
{
UIFont *theFont = [UIFont fontWithName:#"AmericanTypewriter" size:FONT_SIZE];
self.layer.sublayerTransform = CATransform3DMakePerspective(-1000.0f);
topHalfCharLayer2 = [CATextLayer layer];
topHalfCharLayer2.bounds = CGRectMake(0.0f, 0.0f, CHARACTERS_WIDTH, 100.0f);
topHalfCharLayer2.string = #"R";
topHalfCharLayer2.font = theFont.fontName;
topHalfCharLayer2.fontSize = FONT_SIZE;
topHalfCharLayer2.backgroundColor = [UIColor blackColor].CGColor;
topHalfCharLayer2.position = CGPointMake(CGRectGetMidX(self.bounds),CGRectGetMidY(self.bounds));
topHalfCharLayer2.wrapped = NO;
topHalfCharLayer1 = [CATextLayer layer];
topHalfCharLayer1.bounds = CGRectMake(0.0f, 0.0f, CHARACTERS_WIDTH, 100.0f);
topHalfCharLayer1.string = #"T";
topHalfCharLayer1.font = theFont.fontName;
topHalfCharLayer1.fontSize = FONT_SIZE;
topHalfCharLayer1.backgroundColor = [UIColor redColor].CGColor;
topHalfCharLayer1.position = CGPointMake(CGRectGetMidX(self.bounds),CGRectGetMidY(self.bounds));
topHalfCharLayer1.wrapped = NO;
//topHalfCharLayer1.zPosition = 100;
[topHalfCharLayer1 setAnchorPoint:CGPointMake(0.5f,1.0f)];
[[self layer] addSublayer:topHalfCharLayer1 ];
[[self layer] insertSublayer:topHalfCharLayer2 atIndex:0];
[topHalfCharLayer1 addAnimation:[self topCharFlap] forKey:#"anythingILikeApparently"];
}
The View which contains this code is loaded by a view controller in loadView. The initChar method is called in the view's initWithFrame method. The target is iOS4. I'm not using setWantsLayer as I've read that UIView in iOS is automatically layer backed and doesn't require this.
A couple thoughts come to mind:
Try adding the 'R' layer to the layer hierarchy before you start the animation.
Instead of inserting the 'T' layer at index 1, use [[self layer] addSublayer: topHalfCharLayer1]; to add it and then do the insert for the 'R' layer with [[self layer] insertSublayer:topHalfCharLayer2 atIndex:0];
Have you tried to play with the layer zPosition? This determines the visual appearance of the layers. It doesn't actually shift the layer order, but will change the way they display--e.g. which layers is in front of/behind which.
I would also suggest you remove the animation code until you get the layer view order sorted. Once you've done that, the animation should just work.
If you have further issues, let me know in the comments.
Best regards.
From the quartz-dev apple mailing list:
Generally in a 2D case, addSublayer will draw the new layer above the
previous. However, I believe this implementation mechanism is
independent of zPosition and probably just uses something like
painter's algorithm. But the moment you add zPositions and 3D, I don't
think you can solely rely on layer ordering. But I am actually unclear
if Apple guarantees anything in the case where you have not set
zPositions on your layers but have a 3D transform matrix set.
So, it seems I have to set the zPosition explicitly when applying 3D transforms to layers.
/* Insert 'layer' at position 'idx' in the receiver's sublayers array.
* If 'layer' already has a superlayer, it will be removed before being
* inserted. */
open func insertSublayer(_ layer: CALayer, at idx: UInt32)