How to rotate a NSTextView - objective-c

I want to have rotatable text edit area like in Adobe Illustrator. I tried several things including subclassing NSTextView and adding coordinate system rotation before the drawing code like this:
#implementation MyNSTextView
-(void)drawRect:(NSRect)dirtyRect
{
NSAffineTransform * trafo = [NSAffineTransform transform];
[trafo rotateByDegrees:45];
[trafo concat];
[super drawRect:dirtyRect];
}
-(void)drawInsertionPointInRect:(NSRect)rect color:(NSColor *)color turnedOn:(BOOL)flag
{
NSAffineTransform * trafo = [NSAffineTransform transform];
[trafo rotateByDegrees:45];
[trafo concat];
[super drawInsertionPointInRect:rect color:color turnedOn:flag];
}
Which results in corrupted display of the text. I also tried to implement the functionality myself by subclassing NSView and assembling the text architecture programmatically. I draw the string with the drawGlyphsForRange: method of my NSLayoutManager. This partly works but gets complicated because I have to rotate the coordinates for the drawing and for handling the mouse clicks I have to convert the mouse location back to old coordinates.
So is this the best way to do it or is there something else?
Edit: I now tried to use CALayer like this:
#implementation MyNSTextView
-(id)initWithFrame:(NSRect)frameRect
{
self = [super initWithFrame:frameRect];
if (self) {
CALayer *myLayer = [CALayer layer];
myLayer.transform = CATransform3DMakeRotation(1.6,1,0,1.0);
[self setLayer:myLayer];
[self setWantsLayer:YES];
}
return self;
}
But this yields a TextView which doesn't show any text (only a cursor) and is not rotated. Is there something else to add to make it work??

You are making it too complicated. Simply set the rotation on the view itself:
[myView setFrameRotation:angleInDegrees];
There is also setFrameCenterRotation, but that is supposed to work only for layer-backed views (which is OK).
There is one caveat which I am still investigating myself: The blinking text cursor becomes really fat when the view is rotated.

Why not make the views layer-backed? You can then just apply an affine transform to the view's layer.
yourView.layer.transform = CATransform3DMakeRotation(M_PI_4, 0, 0, 1.0);

The problem is that you're creating an NSAffineTransform, but you're not attaching it to your text view.

Related

Drawing issues after subclassing NSCollectionView

OK, here's what I have done:
I have an NSCollectionView
I wanted to be able to enable "selecting" items, and drawing a custom border when an items is selected
I subclassed NSCollectionViewItem (to enable selection)
I subclassed NSView for the NSCollectionViewItem view, in order to draw the border
The code
The view item
#implementation MSLibraryCollectionViewItem
- (void)setSelected:(BOOL)flag
{
[super setSelected:flag];
[(MSLibraryCollectionViewView*)[self view] setSelected:flag];
[(MSLibraryCollectionViewView*)[self view] setNeedsDisplay:YES];
}
The custom view
#implementation MSLibraryCollectionViewView
/***************************************
Initialisation
***************************************/
- (MSLibraryCollectionViewView*)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code here.
}
return self;
}
/***************************************
Drawing
***************************************/
- (void)drawRect:(NSRect)rect
{
if ([self selected]) {
//[[NSColor redColor] setFill];
//NSRectFill(rect);
//[super drawRect:rect];
NSColor* gS = [NSColor colorWithCalibratedRed:0.06 green:0.45 blue:0.86 alpha:1.0];
NSColor* gE = [NSColor colorWithCalibratedRed:0.12 green:0.64 blue:0.94 alpha:1.0];
NSGradient* g = [[NSGradient alloc] initWithStartingColor:gE endingColor:gS];
NSColor *borderColor = [NSColor colorFromGradient:g];
NSRect frameRect = [self bounds];
if(rect.size.height < frameRect.size.height)
return;
NSRect newRect = NSMakeRect(rect.origin.x+5, rect.origin.y+5, rect.size.width-10, rect.size.height-10);
NSBezierPath *textViewSurround = [NSBezierPath bezierPathWithRoundedRect:newRect xRadius:7 yRadius:7];
[textViewSurround setLineWidth:2.0];
[borderColor set];
[textViewSurround stroke];
}
}
However, the seems to be something wrong with drawing. For example:
When resizing the Collection View's container, a weird line appears at the outer box
When an Collection View item is not 100% visible (e.g. because it's been scrolled down), the selection border doesn't appear at all (while I would expect it to draw just the visible portion).
Some Examples
What's going on?
P.S. I'm not a guru with drawing and custom views in Cocoa - so any ideas/help is more than welcome!
You switched from asking about a collection view to talking about an outline view, but I assume that was just a mental hiccup.
When an Outline View item is not 100% visible (e.g. because it's been scrolled down), the selection border doesn't appear at all
(while I would expect it to draw just the visible portion).
That's because of this code in your -drawRect:.
if(rect.size.height < frameRect.size.height)
return;
It's specifically avoiding drawing a partial selection outline.
Regarding the weird line, I doubt that has to do with your collection item view's custom drawing. Does it stop happening if you disable the custom drawing? You could experiment with using an ordinary color rather than using the third-party +colorFromGradient: code you're using.
By the way, this line:
NSRect newRect = NSMakeRect(rect.origin.x+5, rect.origin.y+5, rect.size.width-10, rect.size.height-10);
could be written more simply as:
NSRect newRect = NSInsetRect(rect, 5, 5);

UIButton displaying a triangle

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.

NSView with fill ( pattern image) scrolls when window changes size

I have an NSView with a drawRect
- (void)drawRect:(CGRect)rect {
// Drawing code
NSPoint origin = [self visibleRect].origin;
[[NSGraphicsContext currentContext]
setPatternPhase:NSMakePoint(origin.x, origin.y)];
[[NSColor colorWithPatternImage: self.image] set];
[NSBezierPath fillRect: [self bounds]];
}
It draws my pattern perfectly, but i can see the pattern scroll when i change the the size of my window.
i have tried to set the view isFlipped to YES but that doesn't change anything.
You need to do some off-screen drawing first and then draw that result onto the view. For example you can use a blank NSImage of the exact same size as the view, draw the pattern on that image and then draw that image on the view.
Your code may look something like that:
- (void)drawRect:(NSRect)dirtyRect
{
// call super
[super drawRect:dirtyRect];
// create blank image and lock drawing on it
NSImage* bigImage = [[[NSImage alloc] initWithSize:self.bounds.size] autorelease];
[bigImage lockFocus];
// draw your image patter on the new blank image
NSColor* backgroundColor = [NSColor colorWithPatternImage:bgImage];
[backgroundColor set];
NSRectFill(self.bounds);
[bigImage unlockFocus];
// draw your new image
[bigImage drawInRect:self.bounds
fromRect:NSZeroRect
operation:NSCompositeSourceOver
fraction:1.0f];
}
// I think you may also need to flip your view
- (BOOL)isFlipped
{
return YES;
}
Swift
A lot has changed, now things are easier, unfortunately part of objective-C's patrimony is lost and when it comes to Cocoa, Swift is like an orphan child. Anyways, based on Neovibrant's we can deduct the solution.
Subclass NSView
Override draw method
Call parent method (this is important)
Set a fill on buffer within the bounds of the view
Draw fill on buffer
code
override func draw(_ dirtyRect: NSRect) {
super.draw(dirtyRect)
let bgimage : NSImage = /* Set the image you want */
let background = NSColor.init(patternImage: bgimage)
background.setFill()
bgimage.draw(in: self.bounds, from: NSZeroRect, operation: .sourceOver, fraction: 1.0)
}

CALayer - clear internal rendering context in favor of custom drawing code

When subclassing an CALayer and implementing the drawInContext method, I would assume that any drawing I do within there is all that will show up, but instead if I set (for example) borderWidth/borderColor then CALayer will draw a border on it's own above all my custom drawing code.
This is a CALayer subclass:
#implementation MyCustomCALayer
- (id)init
{
self = [super init];
if(self)
{
[self setNeedsDisplayOnBoundsChange:YES];
}
return self;
}
- (void)drawInContext:(CGContextRef)context
{
CGRect rect = CGContextGetClipBoundingBox(context);
CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);
CGContextFillRect(context, rect);
}
#end
Created in a UIView something like:
- (void)ensureLayer
{
if(myLayer)
return;
myLayer = [[[MyCustomCALayer alloc] init] autorelease];
myLayer.borderColor = [UIColor greenColor].CGColor;
myLayer.borderWidth = 1;
myLayer.frame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
}
- (void)layoutSublayersOfLayer:(CALayer *)layer
{
[super layoutSublayersOfLayer:layer];
[self ensureLayer];
if(![[layer.sublayers objectAtIndex:0] isEqual:myLayer])
[layer insertSublayer:myLayer atIndex:0];
}
What happens, is the MyCustomCALayer fills a rectangle with red, this is what I would expect to see and nothing else, since i've implemented the drawInContext method, but instead I see a red rectangle with a green border on top, always on top, i've tried just about every combination I can think of to get rid of the green border being drawn and cannot figure it out.
My reasoning is I would like to use the borderWidth and borderColor and other properties of the CALayer instead of creating my own properties, because the code that I need to draw contains a border, a fill, etc... but the rendering I need to do is not a simple shape. So the only way i've found around this is to set the borderWidth to 0 and add my own property to my subclass, like myBorderWidth, which is ridiculous.
This is done with the latest iOS SDK, but i'd imagine it's the same for Mac.
Hope this makes sense, any thoughts?
Thanks!
You’re out of luck; CoreAnimation doesn’t support overriding its implementation of rendering for the basic layer properties. Please do file a bug.

Scaling UITextView using contentScaleFactor property

I am trying to create a higher resolution image of a UIView, specifically UITextView.
This question and answer is exactly what I am trying to figure out:
Retain the resolution of the label after scaling in iphone
But, when I do the same, my text is still blurry:
self.view.transform = CGAffineTransformMakeScale(2.f, 2.f);
[myText setContentScaleFactor:2.f]; // myText is a subview of self.view object
I have also tried the same in the Apple sample project "UICatalog" to UILabel and it is also blurry.
I can't understand why it would work for Warrior from the other question and not for me. I would have asked there — but I can't seem to leave a comment or a question there.
Setting the contentScaleFactor and contentsScale is in fact the key, as #dbotha pointed out, however you have to walk the view and layer hierarchies separately in order to reach every internal CATiledLayer that actually does the text rendering. Adding the screen scale might also make sense.
So the correct implementation would be something like this:
- (void)updateForZoomScale:(CGFloat)zoomScale {
CGFloat screenAndZoomScale = zoomScale * [UIScreen mainScreen].scale;
// Walk the layer and view hierarchies separately. We need to reach all tiled layers.
[self applyScale:(zoomScale * [UIScreen mainScreen].scale) toView:self.textView];
[self applyScale:(zoomScale * [UIScreen mainScreen].scale) toLayer:self.textView.layer];
}
- (void)applyScale:(CGFloat)scale toView:(UIView *)view {
view.contentScaleFactor = scale;
for (UIView *subview in view.subviews) {
[self applyScale:scale toView:subview];
}
}
- (void)applyScale:(CGFloat)scale toLayer:(CALayer *)layer {
layer.contentsScale = scale;
for (CALayer *sublayer in layer.sublayers) {
[self applyScale:scale toLayer:sublayer];
}
}
UITextView has textInputView property, which "both draws the text and provides a coordinate system" (https://developer.apple.com/reference/uikit/uitextinput/1614564-textinputview)
So i'm using the following code to scale UITextView - without any font changes, without using any "CALayer" property and keeping high quality:
float screenScaleFactor = [[UIScreen mainScreen] scale];
float scale = 5.0;
textView.transform = CGAffineTransformMakeScale(scale, scale);
textView.textInputView.contentScaleFactor = screenScaleFactor * scale;
Comment the last line if you need low quality (but better performance) scaling.
Transform uses view.center as scaling center point, so adding a 'translate transform' is needed to scale around view corner.
Be sure to apply the contentScaleFactor to all subviews of the UITextView. I've just tested the following with a UITextView and found it to work:
- (void)applyScale:(CGFloat)scale toView:(UIView *)view {
view.contentScaleFactor = scale;
view.layer.contentsScale = scale;
for (UIView *subview in view.subviews) {
[self applyScale:scale toView:subview];
}
}