I'm trying to draw an NSTextFieldCell subclass that looks like the rounded event item normal table in iCal.
Based on this question, I've got the following code in my subclass:
- (void)drawInteriorWithFrame:(NSRect)cellFrame inView:(NSView *)controlView {
NSGradient *gradient = [[NSGradient alloc] initWithStartingColor:[NSColor lightGrayColor] endingColor:[NSColor grayColor]];
[gradient drawInRect:cellFrame angle:90];
controlView.layer.cornerRadius = 0.5f;
[[self title] drawInRect:cellFrame withAttributes:nil];
}
But this just draws the cell as a normal rectangle, with the gradient fill, but without the rounded corners. I'm obviously missing something, but what?
What about calling:
[[textfield cell] setBezelStyle: NSTextFieldRoundedBezel];
Based on this question, I've got the following code in my subclass: …
The accepted answer on that question assumes that the cell is in a text field (i.e., it is the only cell in the view and it effectively is the entire view), and that that view is or can be layer-backed.
That won't work when you're a table column's cell, because you are not supposed to redraw the whole view and making it layer-backed probably isn't going to work correctly. (I'm not sure one can expect layer-backing a text field to work correctly, either. Anything beyond a plain NSView either is made to work layer-backed or isn't; if the documentation doesn't say it is, assume it isn't.)
[gradient drawInRect:cellFrame angle:90];
But this just draws the cell as a normal rectangle, with the gradient fill, but without the rounded corners.
Yup. That's all this method does, so without the rounded corners being already specified (e.g., as the corner radius of a layer), you need to construct and draw the shape with rounded corners yourself.
To do that, create a path for a rectangle with rounded corners, and draw the gradient in that.
Related
I'm trying to implement a custom slider in Cocoa with 5 values. See my demo project, which can be downloaded here: http://s000.tinyupload.com/index.php?file_id=07311576247413689572.
I've subclassed the NSSliderCell and implemented methods like drawKnob:(NSRect)knobRect and drawBarInside:(NSRect)cellFrame flipped:(BOOL)flipped etc.
I'm facing some issues:
I'm not able to position the knob correctly regarding to the background image. I know that I'm able to change the knob's frame, and I've tried doing some calculation to position the knob correctly, but I'm not able to make it work for my custom slider. Could someone please help me with this?
The height of my custom slider background is 41px. In the drawBarInside:(NSRect)cellFrame flipped:(BOOL)flipped I change the height of the frame to 41px as well, but the entire background is not visible. Why?
I've noticed that the included images (the background and knob) are flipped vertically. Why? Note that the border top is darker in the background compared to the bottom, but this is reversed when I draw the background.
I found a mistake in your calculation of the x position of the knob rectangle: You used the height of the image where you should have used the width.
The cell drawing is being clipped to the frame of the control. Maybe you could expand the control frame when your cell awakes.
You need to use the NSImage method drawInRect:fromRect:operation:fraction:respectFlipped:hints:, and pass YES for the respectFlipped: parameter. Apple's controls generally do use flipped coordinates.
Added: Expanding the frame in awakeFromNib doesn't seem to work, the frame gets set back. Here's something that does work. Instead of overriding drawBarInside:flipped:, add this override:
- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView
{
NSRect controlFrame = [controlView frame];
float bgHeight = self.backgroundImage.size.height;
if (controlFrame.size.height < bgHeight)
{
controlFrame.size.height = bgHeight;
[controlView setFrame: controlFrame];
}
[self.backgroundImage
drawInRect: [controlView bounds]
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0
respectFlipped: YES
hints: NULL];
[self drawKnob];
}
If I remove this method from my view everything works fine (no content disappears if I click on a button), so this is definitely the cause.
I'm trying to make a window that is rounded and has a gradient via the code below. Is there anything wrong with this at all that could cause content on the view to disappear?
- (void)drawRect:(NSRect)dirtyRect
{
[NSGraphicsContext saveGraphicsState];
NSBezierPath *outerClip = [NSBezierPath bezierPathWithRoundedRect:[self bounds]
xRadius:3.0
yRadius:3.0];
[outerClip setClip];
NSGradient* aGradient = [[NSGradient alloc]
initWithStartingColor:[NSColor colorWithCalibratedWhite:1.0 alpha:1.0]
endingColor:[NSColor colorWithCalibratedWhite:0.65 alpha:1.0]];
[aGradient drawInRect:[outerClip bounds] angle:270];
[NSGraphicsContext restoreGraphicsState];
}
Switching to NSGradient drawInbezierPath fixes the issue.
I know you answered your own question but I thought I would share why your content was vanishing with the above code.
When you use setClip you are removing the previous clipping path and replacing it with your new path. This means you will wind up drawing outside of the dirty area, thus overwriting previously drawn content.
I had the same issue with drawing rounded corners on my own splash screen, and eventually found a different way to do what I wanted.
Also, you can use the clipRect: class method of NSBezierPath to change the clipping path to the intersection of the existing path and the area you want to restrict drawing into. Of course, save and restore the graphics state around your call to clipRect:.
I am trying to set the backgroundView parameter of a UITableViewCell, but the backgroundView is overlapping the bounds of the cell. I have tried setting masksToBounds to YES, but that doesn't seem to make a difference. Please can you tell me where I am going wrong?
Here is an image showing my problem:
Here is my code:
UIImageView *iv = [[[UIImageView alloc] initWithFrame:cell.frame] autorelease];
[iv setImage:[UIImage imageNamed:#"paper"]];
[iv.layer setMasksToBounds:YES];
[cell.layer setMasksToBounds:YES];
[cell.contentView.layer setMasksToBounds:YES];
[cell setBackgroundView:iv];
Using masksToBounds doesn't work because the bounds of the cell are a rectangle.
Even if the corners of the cell are rounded, they're still part of the cell (but they contain transparent pixels). When a cell is displayed in a grouped table view, its background view (and its selected background view) is drawn in regard of its position in its section (middle, top, bottom, single).
So, if you want to provide a custom background view, you need to compute the position of the cell in its section and provide the adequate background :
either by using 4 different images
or by using the mask property of the background image's layer
or by subclassing UIView and implementing drawRect: so the graphic context is clipped before the image is drawn.
Are you setting every cell that background view, if so why don't you just set it to the table view background.
I'm having some trouble drawing a custom gradient background in a UITableViewCell when the style is set to 'grouped' and the cell is first or the last one of the section. My approach is to simply create a CAGradientLayer and add it to the view like this:
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = rect;
gradient.colors = [NSArray arrayWithObjects:(id)[_backgroundColorLight CGColor], (id)[_backgroundColorDark CGColor], nil];
[self.backgroundView.layer insertSublayer:gradient atIndex:0];
self.backgroundView.layer.masksToBounds = YES;
Unfortunately this produces cells like this one:
Does anyone have a hint on how to make the background fit the boarders of the cell?
Thanks
–f
If you draw a custom background, you also have to draw the borders yourself. There's quite some open source stuff out there.
Basically, you need to know [in the cell] if it's top/middle/bottom/single, and cut the stuff in drawRect. You won't come far with insertSublayer.
Check out the PageCellBackground class you find here:
http://cocoawithlove.com/2010/12/uitableview-construction-drawing-and.html
I've not tried it but CAGradientLayer happens to be a subclass of CALayer, so perhaps setting its borderRadius may work. But it rounds all corners then, so you may compensate for that by making the layer bigger than the cell and have the cell view cut it off.
Look at Rounded UIView using CALayers - only some corners - How? for more examples
I created a custom view to a button, as I need to implement some highlighting when the mouse is over. The class is very simple, and I already implemented mouseEntered: as well as mouseExited:. The view was registered for tracking in the init method (not sure if it's the best place).
The problem is drawing. I keep an ivar mouseOver, set to YES on mouse enter and NO on mouse exited. The other ivar is for the image, called image. The difference between mouse over or not when it comes to drawing, is the transparency. Here is my drawRect::
- (void)drawRect:(NSRect)dirtyRect
{
[image drawAtPoint:NSMakePoint(0.0,0.0)
fromRect:dirtyRect
operation:NSCompositeCopy
fraction:((mouseOver) ? 1.0 : 0.0)];
}
It works nicely, but only when the mouse first entered, apparently. I guess the problem is that the view is not cleared before drawing the other image. I tried adding:
[[NSColor clearColor] set];
NSRectFillUsingOperation(dirtyRect, NSCompositeClear);
But without success. How can I fix this?
[NSColor clearColor] is a purely transparent color. You probably want to fill using a color with some opacity, like, say, [NSColor whiteColor].