I have a really large image that I want to use as a background image of a view. However, I don't want to display the entire image at once; I want only a part of the image to be displayed, and then I want to animate it to display other parts of it, similar to the "infinite background" in games (only not infinite in my case ;)).
What is the best way to do this? Will I have to separate the image in several pieces and then somehow animate the transition between the pieces, or is there a better way?
How about having UIScrollView as a background view? You can then put UIImageView inside that scroll view and control scroll view's contentOffset as needed.
I found the solution. This piece of code does the magic:
self.backgroundImageView = [[UIImageView alloc] initWithFrame: self.view.bounds];
self.backgroundImageView.image = [UIImage imageNamed:#"background.png"];
self.backgroundImageView.contentMode = UIViewContentModeBottomLeft;
[self.view addSubview: self.backgroundImageView];
The key was setting the contentMode to UIViewContentModeBottomLeft.
Related
Im a beginner in programing iOS, so I have 2 questions:
1- I have a UIViewcontroller which load a few uiview and user is able to move them via touch. Now I want to put an image background in this way:
UIImageView *backgroundView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"board.png"]];
[self.view addSubview:backgroundView];
But the image covers over all uivews!!
2- As I said, I move my uiviews by touch and when they have collided in the end touch they both goes in a folder, and a folder is created. So I want to know how I can make that a special image shows on the created folder ??
if (view != toMove && CGRectContainsPoint(view.frame,toMove.center)) {
viewToBefolder = view;
}
You can add your background view first, and then the rest of the views you add will be on top, or just do this:
[self.view sendSubviewToBack:backgroundView];
If your image view is covering the the background, you should be setting the size and position of the image view, or setting the constraints so that it is added at the size and position that you want.
Set your imageview into the main window.
UIImageView *backgroundView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"background.png"]];
[self.window addSubview:backgroundView];
[self.window sendSubviewToBack:backgroundView];
Then set all your view controller view clear color. so, By default it's always display background image view into the all view.
I'm using a simple code to add some images to my UIScrollView. Also I've implemented another code to detect touches on each image.
Here is the code:
(void)handleSingleTap:(UIGestureRecognizer *)sender
{
int senderTagIs;
senderTagIs = sender.view.tag;
if (sender.view.layer.borderColor != [UIColor cyanColor].CGColor) {
sender.view.layer.borderColor = [UIColor cyanColor].CGColor;
UIImageView *showFullImage = (UIImageView *)[self.view viewWithTag:sender.view.tag+100];
[showFullImage setTag:sender.view.tag+200];
[self.view addSubview:showFullImage];
showFullImage.hidden = NO;
NSLog(#"Show tag is: %i", sender.view.tag);
}
else
{
sender.view.layer.borderColor = [UIColor whiteColor].CGColor;
UIImageView *hideFullImage = (UIImageView *)[self.view viewWithTag:sender.view.tag+200];
[hideFullImage setTag:sender.view.tag+100];
hideFullImage.hidden = YES;
NSLog(#"Hide tag is: %i", sender.view.tag);
}
}
The above code, sets the border color to cyan and show my small images from UIScrollView, in another UIImageView.
But my problem is, that I can't set the option to hide all images and set border color white for all images when one image is touched.
Ex: If I touch the first image, then the code will work, my big UIImageView will show touched image and touched image from UIScrollView will get the cyan color for border, so far so good.
Now, If I touch third image, my first image is shown, the color border is cyan, and so... I have to touch first image again to disable, but this is not what I want.
So, we've got a few things going on here. First, I'm assuming you're trying to show a collection of images in a scroll view with some custom padding to indicate selection around them. This sounds tailor make for using UICollectionView with a custom cell.
Absent further information, you're not resetting the old color. Either keep a reference to a selected image as a class variable or, assuming your image views are in a collection object like an NSArray, begin your method by iterating through the objects and resetting their view to an unselected state.
If you just need to hack together a solution, the second option should work. I really recommend using UICollectionView. It's a bit more work in the beginning, especially if you're not experienced with it, but it's well worth learning. Here's a good tutorial on UICollectionView.
I´m build a swipe feature for my todo-list application. When a user swipes(drag) the cell horizontally I would like to display a background image that covers the gap between the screen edge and the cell edge.
When I add an image to the imageView-property it just follows the cell. Can I somehow fix it to cover the whole background?
It sounds like you want to make something like Clear.
What you will need to do is:
Subclass UITableViewCell
Add your image view like this..
UIImageView *imageView = [[UIImageView alloc] initWithFrame:self.bounds];
imageView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
imageView.image = myImage;
[self insertSubview:imageView atIndex:0]; //I'm not at a compiler, so I'm not 100% on this, but it's something like this.
Add a UIGestureRecognizer to handle gestures, and set up dragging and appropriate actions.
Every screen of my app has a common tint. Its not a background. Its a pattern that fills the entire screen and it is top of all the views. You can see the pattern flow continuously from one view to another inside the same screen. And it neither obscures other elements nor participate in event handling.
I tried implementing it with this code in my ViewController.
UIColor* texture = [UIColor colorWithPatternImage:[UIImage imageNamed:#"Texture.png"]];
UIView* tintView = [[UIView alloc] initWithFrame:self.view.bounds];
[tintView setBackgroundColor:texture];
[tintView setAlpha:0.5];
[self.view addSubview:tintView];
But it doesn't pass on touches to the views behind it.
tintView shouldn't participate in any event handling. Rather it should let other elements behind it, handle the events like they do it normally.
Other way of doing it is set this as a background of the view property of a UIViewController and set a common alpha for all other subviews of view to show the pattern behind. That will be redundant in most ways.
Any better way of doing this?
Make your tintView a subclass of UIView and implement the hitTest:withEvent: method, returning nil. This will make your view transparent to touches. Or set userInteractionEnabled to NO.
Set the background color with a Textured image
UIImage *bgimg = [UIImage imageNamed:#"Texture.png"];
self.view.backgroundColor = [UIColor colorWithPatternImage:bgimg];
I designed a very simple interface for an ipad device: UIView + a navigation bar.
Then after the view is load, it will download an image from a location and use the following method to display it:
-(void)connectionDidFinishLoading:(NSURLConnection *)connection{
UIImage* testImg = [UIImage imageWithData:_networkData];
UIImageView* testView = [[UIImageView alloc] initWithImage:testImg];
[_view addSubview:testView];
[testView release];
}
The problem is now the new UIImage occupies the whole visible area of the Ipad.
I wonder how can I fix this issue? I suppose I have to find out the frame of the display area in the original view, and then assign it to the UIImageView instance?
initWithImage will automatically adjust the frame to match the size of the image you're passing in. To tell the UIImageView to take the same size as its parent view you could just add the following line before you add the subview:
testView.frame = _view.bounds
...we use bounds rather than frame because the superview may have an offset that we don't want the image view to have.