I have a UIView and I change the frame size but I dont think the layer is resizing. How does one resize the layer with the frame without overriding layoutSubviews?
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I have a UIImageView. For some reason, the circle crop is not working properly. What it winds up doing is cropping the edges to a circle, but leaves the sides completely straight, any ideas why?
Here is my code:
self.avatarTwo.layer.cornerRadius = self.avatarTwo.frame.size.height /2;
self.avatarTwo.layer.masksToBounds = YES;
self.avatarTwo.layer.borderWidth = 0;
The image is 2448 by 3264 (pixels) and this is how it looks right now cropped:
Although the UIImageView is square, the UIImage's height is much larger than the width. The default content mode for UIImageView is UIViewContentModeScaleToFill which scales the content "to fit the size of itself by changing the aspect ratio of the content if necessary." To make the image centered and filling the UImageView you must use:
self.avatarTwo.contentMode = UIViewContentModeScaleAspectFill;
See contentMode for more information on this.
In essence, your UIImageView is being cropped fine, but the content in that image view is being scaled to not crop any of the content.
I have an Image inside UIScrollView which i can zoom in and out.
I have a button that let the user rotate the Image 90 degrees:
(void)RotateImage {
CGAffineTransform rotateTrans = CGAffineTransformMakeRotation(-90.0 / 180.0 * 3.14);
BaseImg.transform = rotateTrans;
}
After the imaged is rotated i cannot zoom in and out.. the image is going crazy on the screen and going back to the UNRotated state.
What am i doing wrong? code examples will be great!
Thanks :)
UIScrollView likes to take over the transforms of the views it contains. There are two solutions:
Rotate the image without changing the containing view.
Create a UIView subclass that displays an image within a sublayer.
To rotate the image, see How to Rotate a UIImage 90 degrees?. If you're always and only doing 90 degree rotation, see #Peter Sarnowski's solution. To adapt it to what you're doing here, assuming that BaseImg is a UIImageView:
- (void) rotateImage
{
UIImage *sourceImage = [baseImg image];
UIImage *rotatedImage = [UIImage imageWithCGImage:[sourceImage CGImage] scale:1.0 orientation:UIImageOrientationRight];
[baseImg setImage:rotatedImage];
}
This will only rotate once. To have rotateImage work repeatedly, read the existing orientation property and move it on to the next in clockwise or anticlockwise order.
If the image is not square, you may also need to resize baseImg to reflect its new aspect ratio.
To create a UIView subclass, you need to have it store a CALayer as a sublayer of the view layer. Store the image in the sublayer, and transform the sublayer at will. This is faster, and allows arbitrary rotation, but you need to calculate your own scaling to prevent the rotate image going outside the view bounds.
To simply rotate image the code is perfect but to add zoom in and out and then add rotation you need to retain its transforms.Here is a sample code that can help you.
https://github.com/elc/iCodeBlogDemoPhotoBoard
I have a UIImageView as a subview of UIView (frame size 300 x 300). My UIImage would be either portrait, landscape or some odd sizes. How do I fill in the UIImage within the UIView frame size without stretching the image to 300 x 300?
The purpose of this, I will be adding another UIImageView as the image border.
Please help.
Thanks.
Try
[img setContentMode:UIViewContentModeScaleAspectFit];
UIViewContentModeScaleAspectFit: Scales the content to fit the size of the view by
maintaining the aspect ratio. Any remaining area of the view’s bounds is transparent.
or [img setContentMode:UIViewContentModeScaleAspectFill];
UIViewContentModeScaleAspectFill: Scales the content to fill the size of the view. Some
portion of the content may be clipped to fill the view’s bounds.
if you are clipping subviews, then you need to do
[imgView clipToBounds:YES];
Ah I just reread what you were asking, I know what your question is now.
Your UIImageView's frame changes, and when it does so does your image. You don't want your image to change, but you do want your ImageView to adjust to fill the view it is contained in.
UPDATE
I figured it out.
[self.imageView setContentMode:UIViewContentModeCenter];
No matter what orientation, the size stays the same.
You also have the option of setting it to align top, bottom, left, right, top left, top right, bottom left, bottom right, all of which only help to align your image and NOT redraw or re-size the image.
Does that help?
[image setContentMode:UIViewContentModeScaleToFill];
Set the contentMode property of UIImageView to either of this values depending on where you want to put it in the superview:
UIViewContentModeCenter,
UIViewContentModeTop,
UIViewContentModeBottom,
UIViewContentModeLeft,
UIViewContentModeRight,
UIViewContentModeTopLeft,
UIViewContentModeTopRight,
UIViewContentModeBottomLeft,
UIViewContentModeBottomRight,
As this values:
UIViewContentModeScaleToFill,
UIViewContentModeScaleAspectFit,
UIViewContentModeScaleAspectFill,
Will indeed cause the image to be 300 x 300, which is what you don't want.
Use the contentMode property of UIImageView.
Edit: and set the image size to 300x300.
The frame size is adjustable so using a png for background is not an option
Set background color of your view to clearColor, then either set border property to view's layer (see here how-to), or in view's drawRect: method stroke a rectangular path on the border of the view
I have a big problem concerning the resizing of a derived UIView with a UIScrollView as subview.
In the layoutSubviews message I set the frame of the UIScrollView subview. the UIScrollView contains a UIImageView with a big image which can be moved/pinched and so on. The initial contenSize of the UIScrollView is the initial image size.
So far, so good. Moving and pinching of the image works well. Now I have to change the UIView frame (in my app to maximize the UIView). im doing that in a animation block (beginAnimations/commitAnimations). So I set the new frame (which will update the width & height) an then I call [myView layoutIfNeeded] to force the UIScrollView to update its frame in the layoutSubviews message of my view.
The UIView animates correct to its new frame and if the contentOffset of the UIScrollView is currently x 0, y 0 the UIScrollView frame will be updated properly. but here's my problem: if the contentOffset of the UIScrollView is bigger than x 0, y 0 the UIScrollView will "slide in" from upper left to its final position.
I want that the UIScrollView resizes its frame properly with the parents frame and aligns the content (in my case the UIImageView) right. But how could I achieve that?
after hours of web research i found the solution for this problem:
[UIView setAnimationBeginsFromCurrentState: YES];
this will animate all layers from the current state.