I have a IKImageView and a NSImageView as a subview. Subviews are supposed to get drawn above their master view. I tried an NSImageView with the same subview, and it worked fine, but I really need to be able to move the image around with the mouse, and zoom it with a slider, and I think IKImageView is a bit easier.
What happens is this:
As you can see, the small picture (subview) is below the image on the IKImageView, but in front of the background of IKImageView.
How can I fix this?
ps: Do you think I should use NSImageView? If so, how would I move it around, and zoom?
call addSubview again everytime after I set the IKImageView's image.
That work for me.
Related
I got wiered but unsurprising animation from call UIView animation, I don't know if it works the same by using CALayer animation. I guess it is.
please see this picture: what I want is to animate a horizontal bar growing horizontally, what I do is:
Subclass a UIView, called UIViewBar, and in its drawRect:rect method, I draw the shape of rectangle and a right cap, it's done by
CGContextMoveToPoint A
CGcontextAddLineToPoint B
CGContextAddArcToPoint D
CGContextAddLineToPoint C
//then close the path and fill the context
Then I call this UIViewBar (initWithFrame:rect) in my UIViewController, and the shape is what I want, looks fine. BUT when I perform [UIView animation] say from original rect to rectGrew it does not perform nicely. Instead, it perform as the picture says.
Well, after thinking, it's not totally unreasonable because when the UIView horizontally stretches itself, it does not know the cap will not be changed. So is there another way to do this?
Actually, I'm very new to drawing, graphic, and animation. What I know is that (if wrong please kindly correct me):
If I want to "draw something", I should override the UIView's drawRect method, and this is done by initing the UIView, should not or better not to be called outside. Say I drew a rectangle in a UIView by CGContextFillRect.....
But what if I want to animate this rectangle? I cannot make animation based on Quartz2D, but from UIView animation or CALayer(deeper tech), so What I have to do is to make the rectangle itself as a seperate UIViewRect seperately, so I can call the [UIViewRect animation] method, AM I RIGHT ON THIS
If so, I have to make every rectangle that I want to animate to be UIView respectively. Doesn't it affect performance? Or it is just the way apple prefers to do ?
Any suggestion will be much helpful, GREAT thanks.
Wow, it's the first time that no answer posted at all! TO answer my question: it requires to consider animate custom property of CALayer. The custom property is the AB width (the width without cap width, that should work). If someone wants detailed code. Please google custom property animate in CALayer.
I have an UIScrollView which contains one UIImageView. Everything is working correctly, I can zoom in and out, when zoomed in I can pan around, etc.
The problem that I am unable to solve is how to pan a zoomed out image around the screen. The user needs to be able to zoom the image out until it's small, and then move that small image to any point on the screen. Sadly, it's stuck in the center of the screen (usually, it would be stuck in the top left corner but I did fix that problem).
There are a couple of things you need to do here. I suggest doing them in viewWillAppear rather than viewDidLoad because if you're using storyboards, it doesn't work quite right in viewDidLoad.
First, you need to set the content size property of your scroll view to be the size of the photo itself because you want the entire area of your photo to be scrollable.
self.scrollView.contentSize=self.photoShown.size;
photoShown is UIImage. scrollView is a UIScrollView
Second, you need to set the frame of your UIImageView that houses your image to be the size of your image:
self.imageView.frame=CGRectMake(0,0, self.photoShown.size.width, self.photoShown.size.height);
if you haven't done this, then the frame of the UIImageView is the size of the screen itself and there is simply nowhere to pan. That's why it needs to be bigger, so you can pan to the regions not currently shown on screen.
So, I have a CALayer added to a UIScrollView that does some path animations. In my application, I resize the scroll view and shift everything to create a "negative" region. Using contentOffset with UIScroll views, all my subviews are shifted and there is no flashing effect. However, when the lines on the CALayer are shifted, there is a flashing effect because they are drawn in the "negative" area first, then shifted over.
This was happening as an animation at first, but I used CATransaction -begin and -commit to remove the animation. The flashing is still occurring though because the lines are still drawn and then moved.
Is there anyway to solve with?
Thanks in advance.
Edit: I figured out a way to fix this. Before, I was adding each animation to an animation layer, which was then added to the UISCrollView. Instead, I added each animation directly to the UISCrollView and then shift all layers appropriately as before. CATransaction -begin and -commit are still needed to remove any sort of animation of the shift.
I figured out a way to fix this. Before, I was adding each animation to an animation layer, which was then added to the UISCrollView. Instead, I added each animation directly to the UISCrollView and then shift all layers appropriately as before. CATransaction -begin and -commit are still needed to remove any sort of animation of the shift.
I have an NSImageView in a view that utilizes Core Animation. Prior to using Core Animation the image looks fine but now its blurry and low quality. If I let NSImageView have a bezel border the issue goes away but I need it to have no border. Had this happened to anyone else?
Imgae in the background with no border, same image in the front with a border.
Thanks
EDIT: I forgot to mention that the image is an icon file (ICNS) so it has various sizes. The bordered view loads the correct size and the transparent one loads the smallest and stretches it.
Although not the way I wanted to, I managed to create a fix for the issue. The issue seemed to be the way that NSImageView was drawing the image so I created a custom NSView subclass with support for the same bindings I used in my original image view. Im not sure why the blurry-ness happend in the beginning, but drawing the image by hand in an NSView seems to do the trick.
Your image may be drawing in a non-pixel-aligned way. Have you tried shifting it by a half pixel?
Apple has a good demonstration of this in the BlurryView app in their "Cocoa Tips and Tricks" sample code.
Cocoa Tips and Tricks
I'm adding a CATiledLayer backed UIView in UIScrollView.
When the view is first loaded, I'm trying to fit the UIView, by setting the zoomScale of UIScrollView - this fits the UIView and the layered contents.
I'm having a method to fetch the tiles of image and I'm rendering them in drawLayer:inContext:
Now even if the contentsize of scrollview/frame of CATiledLayer view is greater than UIScrollView, it doesn't scroll initially.
The moment I try to zoom by pinching the screen, I'm able to scroll perfectly.
I can't scale the CGContext in drawLayer:inContext, since the context I receive is of a tile and not whole image and I have 20 tiles which make up my image.
At the end of the initWithFrame of the PDFScrollView i added the line:-
self.zoomScale = 1.0;
This worked for me.
The code is pretty much doing the same stuff as apple example
http://developer.apple.com/library/ios/#samplecode/ZoomingPDFViewer/Introduction/Intro.html%23//apple_ref/doc/uid/DTS40010281-Intro-DontLinkElementID_2
which also doesnt scroll on loading