UIImageView change Width and Height - iphone

I've read various posts on here asking similar questions... I've tried various ways that were posted including bounds and frames etc. including the following:
myImage.frame = CGRectMake(0.0f, 0.0f,50.0f, 50.0f);
and:
myImage.bounds = CGRectMake(0.0f, 0.0f,50.0f, 120.0f);
neither of those work.
However, I find it interesting that the following code let's me move the Image around but doesn't change the width:
CGRect frameRect = myImage.frame;
frameRect.size.width = 50.0f;
frameRect.origin.x += 10.5f;
myImage.frame = frameRect;
So why don't any of these change the width/height of my ImageView?
I found another post on here that basically states I have to right a small book of code to get it resize my image... is that true?
Such as this one:
UIImage: Resize, then Crop
certainly this is simpler than that??

The following will change the size of the UIImaveView, clipping the underlying image without resizing it and keeping it aligned to bottom left of view:
imageView.frame = CGRectMake(
imageView.frame.origin.x,
imageView.frame.origin.y, newWidth, newHeight);
imageView.contentMode = UIViewContentModeBottomLeft; // This determines position of image
imageView.clipsToBounds = YES;

First off, you can't set the frame or bounds of the UIImage - that will only work on a UIImageView.
I've found that changing the frame of a UIImageView causes the Image to be scaled to the new size. Sometimes, that's undesirable - and you want instead to crop the image.
I can't tell if this is what you're asking for, but here's some code to crop an image to a specific size in a UIImageView:
UIImage *myImage = [UIImage imageNamed:#"photo.png"];
CGRect cropRect = CGRectMake(0.0, 0.0, 320.0, 44.0));
CGImageRef croppedImage = CGImageCreateWithImageInRect([myImage CGImage], cropRect);
UIImageView *myImageView = [[UIImageView alloc] initWithFrame:cropRect];
[myImageView setImage:[UIImage imageWithCGImage:croppedImage]];
CGImageRelease(croppedImage);

From what I get of the question, the OP wanted to change the size of the UIImageView when the size of the container UIView is changed. The code below will do it...
UIView * foo = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, 25, 25)] autorelease];
foo.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
UIImageView * bar = [[UIImageView alloc] initWithImage:
[UIImage imageNamed:#"test.png"]];
bar.autoresizingMask = foo.autoresizingMask;
[foo addSubview:bar];
[self.view addSubview:foo];
The key here are the foo.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight and the bar.autoresizingMask = foo.autoresizingMask; lines. Forget either of these, and the whole jigmarole will stop working.

Well, if your read the documentation about UIIMage you can notice that is impossible to change any parameter of an UIImage after create it, the solution I've implemented for use high quality images for change some parameter of (for example) the SliderControl as Screw Image, is the next one:
UIImage *tumbImage= [UIImage imageNamed:#"screw.png"];
UIImage *screw = [UIImage imageWithData:UIImagePNGRepresentation(tumbImage) scale:2];
With that, I can to use 100x100 px image in my apps scaled to 50%.
Kind regards.

Try Using a UIScrollView. Add the UIImageView to the UIScrollView in Interface Builder you can then control the position and size of the image as follows:
CGRect rect = [scrollView frame];
rect.origin.x = 50.0f;
rect.origin.y = 0.0f;
rect.size.width = 320.0f;
rect.size.height = 150.0f;
[scrollView setFrame:rect];

If you tried those methods cannot work, the only way to do it is to add the constraint of width and height to the UIImageView.
// Create the constraint in code
NSLayoutConstraint *constraint0 = [NSLayoutConstraint constraintWithItem: myImage attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeWidth multiplier:1.0f constant: yourNewsWidth];
NSLayoutConstraint *constraint1 = [NSLayoutConstraint constraintWithItem: myImage attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeHeight multiplier:1.0f constant: yourNewsHeight];
[myImage addConstraint:constraint0];
[myImage addConstraint:constraint1];

Use myImageView.frame = myNewPosAndSize; to resize or reposition your image view (as with any other view). It might confuse you that the image view draws its image with its original size, possibly exceeding its own dimensions. To disable this use myImageView.clipsToBounds = NO;

You don't have to write a whole book, you can copy that code.
I believe the UIImageView always draws the image at 0,0 at a 1.0 scale. You'll need to resize the image if you want to continue using the UIImageView.

Related

How to repeat image horizantly in dynamic creation in ios

Could any one help me i want to add same image multiple times horizontally with same height and width. Important thing is i am creating image view dynamically i want to use same image view for all images! This is image i want to make horizontally like this but only one row needed like this.
You could achieve this by using stretchableImageWithLeftCapWidth:
UIImage *backgroundImage = [[UIImage imageNamed:#"SheetBackground.png"] stretchableImageWithLeftCapWidth:0.5 topCapHeight:0];
As per your request:
UIImage *backgroundImage = [[UIImage imageNamed:#"q4Ses.png"] stretchableImageWithLeftCapWidth:0.5 topCapHeight:0];
[_scro setBackgroundColor:[UIColor colorWithPatternImage:backgroundImage]];
And using your image:
The output is:
You can set this image on top of either UIScrollview, UIView and buttons. You do not need a for loop for that.
UPDATE:
The above code is for filling the entire background. If you wish to add only for one row then you have to create one UIView and set its colorWithPatternImage like below:
UIImage *backgroundImage = [[UIImage imageNamed:#"q4Ses.png"]
stretchableImageWithLeftCapWidth:1 topCapHeight:0];
UIView *v=[[UIView alloc]
initWithFrame:CGRectMake(0, 0, _scro.frame.size.width, 45)];
[v setBackgroundColor:[UIColor
colorWithPatternImage:backgroundImage]];
[_scro addSubview:v];
And the output:
Make a view of the height of image. But this view can have any width.
Then set your tile image in this view with following code.
UIImage *tiledImage = [UIImage imageNamed:#"myTiledImage.png"];
self.view.backgroundColor = [UIColor colorWithPatternImage:tiledImage];
This will get you the image tiled multiple times horizontally.
If the view spreads the image everywhere on screen then you'll have to add the following code to your view
self.view.clipToBounds = YES;
UIScrollView *myScrollView=[[UIScrollView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];
CGFloat scrollWidth = 0.f;
for (int i=0;i<10;i++)//i=10,put as many image number u want to display
{
imageView = [[UIImageView alloc] initWithFrame:
CGRectMake(scrollWidth, 0, 80, 60.f)];
imageView.image=[UIImage imageNamed:#"urimagename"];
imageView.tag=i;
[myScrollView addSubview:imageView];
scrollWidth += 100;
}
myScrollView.contentSize = CGSizeMake(scrollWidth, 100);
EDIT:
You can achieve this in one more way.
CodenameLambda1's answer is better than the above one.But still some changes needs to be done in the #CodenameLambda1's answer..as the SOP's requirement is to display it in scrollview.So instead of self.view use scrollview.
UIScrollView *vie=[[UIScrollView alloc]initWithFrame:CGRectMake(0, 0, 320, 60)];
UIImage *tiledImage = [UIImage imageNamed:#"login"];
vie.backgroundColor = [UIColor colorWithPatternImage:tiledImage];
vie.contentSize=CGSizeMake(1400,60);
vie.clipsToBounds = YES;
[self.view addSubview:vie];

Display Top Portion of UIImageview

I'm trying to display a top portion of an UIImage.
I know I can use the following code and display the middle portion. I'm just trying to figure out how to do the same for the top portion:
imageView.contentMode = UIViewContentModeScaleAspectFill;
imageView.clipsToBounds = YES;
The UIImage I get from the server is not necessarily the same size, so I cannot use UIViewContentModeTopLeft. I want a way to scale the image and show the top portion.
Thanks.
You want to display an arbitrary rectangle of your image, so the easiest way to go will to be to put your imageView inside a regular view. You can set the frame of the image view to display the bit you want and set the enclosing view to do the clipping.
e.g. you have a 1000 x 1000 px image and you want to display the rectangle 200,200 to 400,400
UIImageView* imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"SomeImage"]];
imageView.frame = CGRectMake( -200, -200, 1000, 1000);
UIView* enclosingView = [[UIView alloc] initWithFrame:CGRectMake( 0, 0, 200, 200);
enclosingView.clipsToBounds = YES;
[enclosingView addSubview: imageView];
Content mode doesn't matter much in this case, since you're setting the dimension of the image view to match the image.
One way is to call CGImageCreateWithImageInRect on your original image to create a new image with just the top portion.
Something like:
CGImageRef newImageRef = CGImageCreateWithImageInRect( oldImage.CGImage, CGRectMake(0,0,50,50) );
UIImage *newImage = [UIImage imageWithCGImage:newImageRef];
CGImageRelease( newImageRef );
then display newImage rather than oldImage.

UIView background image resize in proportion

I have a Background.png image with size of 200*100, and i set background image for a uiview as:
UIView view= UIView alloc] initWithFrame:CGRectMake(50, 100, 200, 100)];
view.backgroundColor = [[UIColor alloc] initWithPatternImage:[UIImage imageNamed:#"Background.png"]];
Now, I reset the frame UIView by:
[view setFrame:CGRectMake(50,100,400,200)];
I need to resize the background image in proportion of the uiview, but i have only one fixed size Background.png image. what shall i do.
Take your size accordingly
UIGraphicsBeginImageContext( newSize );
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIView view= UIView alloc] initWithFrame:CGRectMake(50, 100, 200, 100)];
view.backgroundColor = [[UIColor alloc] initWithPatternImage:newImage];
Else take an imageview and set contentMode, If u dont want to tile images
Depending on what your needs are, it might be simplest just to add a UIImageView as a subview of your view, and set its image, letting it handling the resizing for you. Otherwise, you'll probably have some complex resizing and drawing code to write.

uiscrollview not scrolling uiimageview

I'm trying to insert one more image in my UIScrollView. The problem is: all my old content is still scrollable, but this image stay static in the top of the page. Does anybody know a solution?
Code:
- (void)viewDidLoad {
CGRect myImageRect = CGRectMake(0.0f, 0.0f, 320.0f, 109.0f);
myImage = [[UIImageView alloc] initWithFrame:myImageRect];
UIImage * img = [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:#"www.somelink.com"]]];
myImage.image = img;
myImage.opaque = YES; // explicitly opaque for performance
[scrollView addSubview:myImage];
[myImage release];
}
Regards.
I'm guessing that your "old content" is encapsulated in a view and it's that view that is your UIScrollView's subview for content. If that's the case, you should add your new image to that "contentView", adjust its frame and update the scrollview's contentSize based on the new width and height of the content view.
If my guess is wrong, could you please post the code showing how the UIScrollView is created and how the "old content" is added to it?
You might also find this sample code from Apple useful with regard to the layout of subviews of a UIScrollView. (see the - (void)layoutScrollImages method).

How to resize a UIImageView to fit the underlying image without moving it?

I have a UIImageView whose frame, set before the image is loaded, is always too large for the image, so when I try to round the corners, for example, nothing happens.
How can I resize the frame so it's the same size as the underlying image, while ensuring that the center point of the UIImageView does not change?
If you change the bounds of a UIView the center will not change.
CGRect bounds;
bounds.origin = CGPointZero;
bounds.size = newImage.size;
imageView.bounds = bounds;
imageView.image = newImage;
try something along the following lines.. not tested
CGSize imageSize = image.Size;
CGPoint oldCenter = imageView.center;
// now do some calculations to calculate the new frame size
CGRect rect = CGRectMake(0, 0, imageSize.width, imageSize.height);
imageView.frame = rect;
imageView.center = oldCenter;