how can i set the height of UIImageView and leaving other attributes as it is from the .xib? i have UIImageView in .xib file but i only want to set height of it programmatically. can it be done?
Yes It can be done. For eg: If you have UIImageView as imageView then do the below to change the specific frame value.
Way - 1
CGRect rect = imageView.frame;
rect.size.height = /* YOUR_HEIGHT */;
imageView.frame = rect;
Way - 2
imageView.frame = CGRectMake(imageView.frame.origin.x, imageView.frame.origin.y, imageView.frame.size.width, /* YOUR_HEIGHT */);
I highly recommend you to add https://github.com/AlexDenisov/FrameAccessor to your project. It allows to work with frame directly, for example:
view.x = 15.;
view.width = 167.;
Related
This question already has answers here:
How to crop a UIImageView to a new UIImage in 'aspect fill' mode?
(2 answers)
Closed 4 years ago.
I have a UIView. There is a UIImageView inside that UIView. UIImageView doesn't comply to autolayout constraints. Parent UIView's bounds are clipped.
Now content mode of UIImageView is Aspect Fill, but the size of UIImageView is always calculated and set to size of UIImage that is being rendered. So UIImageView's size will always be equal to size of UIImage.
Now UIImageView can be positioned. It has a pan gesture applied to it. UIImageView is being moved within the parent UIView based on requirement of user.
My task is to crop the UIImage of UIImageView to the visible viewport of parent UIVIew only. Core Cropping the image is not issue but finding the visible rect is.
My solution which is not working was to convert frame of parent UIView and child UIImageView to window screen. Then find the intersection of new converted frames. But this is not working. There should be some simple mathematics behind this which I am not able to come up successfully.
This is my code so far.
CGRect imgFrame = [_pageImageView convertRect:_pageImageView.frame toView:nil];
CGRect viewportFrame = [_viewportView convertRect: _viewportView.frame toView:nil];
CGRect visibleRect = CGRectIntersection(imgFrame, viewportFrame);
CGImageRef imageRef = CGImageCreateWithImageInRect([_pageImageView.image CGImage], visibleRect);
UIImage *cropped = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
My objective is to find the visible rect that is visible through clipped parent UIVIew, then crop the UIImageView based on that visible rect. Important note: UIImageView can be positioned and moved within parent UIView.
EDIT: I can't use UIScrollView for cropping as used in many other discussions for my internal reasons.
You can place the image view inside the UIScrollView instead of UIView which make the pan gesture work easier.
I have the scrollview have the UIImageView
- (CGRect)imageCropRect
{
CGSize imageSize = self.image.size;
CGSize contentSize = self.contentSize;
CGRect cropBoxFrame = self.frame;
CGPoint contentOffset = self.contentOffset;
UIEdgeInsets edgeInsets = self.contentInset;
CGRect frame = CGRectZero;
frame.origin.x = floor((contentOffset.x + edgeInsets.left) * (imageSize.width / contentSize.width));
frame.origin.x = MAX(0, frame.origin.x);
frame.origin.y = floor((contentOffset.y + edgeInsets.top) * (imageSize.height / contentSize.height));
frame.origin.y = MAX(0, frame.origin.y);
frame.size.width = ceil(cropBoxFrame.size.width * (imageSize.width / contentSize.width));
frame.size.width = MIN(imageSize.width, frame.size.width);
frame.size.height = ceil(cropBoxFrame.size.height * (imageSize.height / contentSize.height));
frame.size.height = MIN(imageSize.height, frame.size.height);
return frame;
}
I wanted to know how to align an image to the right while keeping the aspect fill. So this is how my image view looks right now.
I would like to move the image to the left, so that the image looks like this.
Now I tried aligning it to the right, but the image is so big that it only shows her gun. So I was wondering how would you be able to do this. Would I have to use a ScrollView? Would appreciate the help, Thanks.
I am not sure if this works for you or not:
Try the different contentModes:
Use it like:
imgView.contentMode = .scaleAspectFit //Or any from below options
You can Use StoryBoard also:
Try different types which suites your useCase
Hope this helps.
Set Content Mode of image Which is best for you Image View.
you could resize imageview as per the image size, below code is not tested:
CGSize kMaxImageViewSize = {.width = 100, .height = 100};
CGSize imageSize = image.size;
CGFloat aspectRatio = imageSize.width / imageSize.height;
CGRect frame = imageView.frame;
if (kMaxImageViewSize.width / aspectRatio <= kMaxImageViewSize.height)
{
frame.size.width = kMaxImageViewSize.width;
frame.size.height = frame.size.width / aspectRatio;
}
else
{
frame.size.height = kMaxImageViewSize.height;
frame.size.width = frame.size.height * aspectRatio;
}
imageView.frame = frame;
For Example:
I can get the height of UIImageView(identifier:ImgView) by the top and bottom constraints and I want to let its width be (4/3 x height).
How can I do it?
I have ever tried doing it by this sentence:
ImgView.frame.width = ImgView.frame.height * 4.0 / 3.0
But it didn't work with an error said:
it can't assign to ImgView.frame.width
So, how can I achieve this?
Use a ratio constraint. Easy peasy.
Try this:
CGRect frame = ImgView.frame;
frame.size.width = frame.size.height * 4/3;
ImgView.frame = frame;
Or a one-liner:
ImgView.frame = CGRectMake(ImgView.frame.origin.x,
ImgView.frame.origin.y,
ImgView.frame.size.height * 4/3,
ImgView.frame.size.height);
I want an image to automatically align to the top, I figure the only want to do this is through making a frame that positions it that way. After doing some research, I can't seem to figure out why this code doesn't move the image at all... I have substituted many values in the topPadding and leftPadding variables..
- (void)constructImageView:(UIImage *)image {
CGFloat topPadding = 20.f;
CGFloat leftPadding = 30.f;
CGRect frame = CGRectMake(leftPadding, topPadding, image.size.width, image.size.height);
self.imageView = [[UIImageView alloc] initWithFrame:frame];
self.imageView.image = image;
[self addSubview:self.imageView];
}
Are you using Autolayout? If yes, setFrame: does not work properly with autolayout. If thats the case, then your options are:
Use this: self.view.translatesAutoresizingMaskIntoConstraints = YES
Write your own constraints instead of setting the view's frame
I need to create two text entry field one beneath the other. When user types in the upper text field, I need to increase the frame size dynamically (scrolling inside the textview is not recommended.) and the lower text entry frame should go downwards. Will this can be possible in ios? Any help will be appreciated.
You can update the frame of your textView via its contentSize like below:
-(void)updateTextViewSize
{
CGRect rect = textView.frame;
rect.size.width = textView.contentSize.width;
rect.size.height = textView.contentSize.height;
textView.frame = rect;
//lowering the textView2 below this textView
//assuming that the lower textview touches the
//bottom of the upper textView.
CGRect rect2 = textViewLower.frame;
rect2.origin.y = textView.frame.origin.y + textView.frame.size.height;
textViewLower.frame = rect2;
//update your scrollView here
//assuming textView and textViewLower are already added to the scrollView
scrollView.contentSize = CGSizeMake(scrollView.contentSize.width, textViewLower.frame.origin.y + textViewLower.frame.size.height);
}
//implement this delegate method as shown below
-(void)textViewDidChange:(UITextView*)textView
{
[self updateTextViewSize];
}
It is easy to do resizing of the UITextView to its correct height according to its content using the UITextView contentSize.
CGRect frame = _textView.frame;
frame.size.height = _textView.contentSize.height;
_textView.frame = frame;