I have a custom UIView that draws some data and another more detailed view that draws some components of the first view. What I want to do is after a gesture, zoom in, hide the first view, and then show the second view to give the user the context that they are zooming in deeper.
I thought I would start by doing something like this:
CGAffineTransform zoomTransform = CGAffineTransformMakeScale(2, 2);
[UIView animateWithDuration:2 animations:^{
self.chromoMap.transform = zoomTransform;
}];
It does zoom in on that area by scaling that UIView. However, I don't want my UIView to actually grow. If my CGRect is {0, 0}, {100, 100}. I want the frame of the UIView to stay the same, but just the contents inside it to scale by 2 to give that zoom effect. How would I do that? Thanks.
It seems I can just add another transparent UIView on top of it with clip subviews enabled to get that effect.
Related
I have a UILabel I want to animate growing and shrinking. While the size changes I need the bottom left corner to remain static so that it always appears directly above a bottom toolbar. I am using the following code to make the label grow:
[UIView animateWithDuration:kAnimationDuration delay:0.0 options:UIViewAnimationCurveEaseInOut
animations:^{
CGFloat lblHeight = 42.0f;
[label setFrame:CGRectMake(0.0,
CGRectGetMaxY(self.view.bounds) - kBottomBarHeight - lblHeight,
CGRectGetMaxX(self.view.bounds),
lblHeight)];
} completion:^(BOOL finished) { }];
and to make it shrink I use the same logic except that lblHeight is set to 17.0f
The view correctly grows but when I try to shrink it the frame change animation is not animated. It blips into the new size and then animates into the new origin/location. I need the frame change to be animated. Can anyone see what I'm doing wrong?
After some tinkering I've managed to get the desired behavior by doing the following.
In the expand method, I use the UIView animation to alter the frame.
In the shrink method, I use the UIView animation to alter the bounds and center.
I'm a little baffled as to why this works but trying to shrink with the frame does not. If anyone can share some insight into this that would be great.
You should not really use frames to animate, rather you should use the transform property of your label.
However, since you want one corner to remain static, I think its best you use Core Animation. CALayer has a property called anchorPoint that determines which point a layer will rotate with respect to, and I'm pretty sure it is also valid for grow/shrink effects.
I have a simple UIView which I'm filling with a patterned background, like this
self.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"backgroundPattern"]];
I want to be able to manipulate the origin of the view by modifying its bounds property and have the background move with the change in origin (as if the background is fixed to the content, not floating behind it). Is this possible? Currently the background seems fixed to the view's frame instead of its bounds and the pattern doesn't scroll when the content scrolls.
To change the origin I'm using a block animation like this
self.bounds = CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height);
[UIView animateWithDuration:1. delay:0. options:UIViewAnimationOptionRepeat animations:^{
self.bounds = CGRectMake(0, 100, self.bounds.size.width, self.bounds.size.height);
} completion:nil];
With that code, my child views repeatedly scroll and reset, but the background stays fixed in place. Is it possible to specify a background which scrolls with the view instead?
I haven't been able to find anything on making a background pattern "stick" to the view's origin system. My solution for my app has been to make a child view and set the background pattern on that. Then the child view will move with the origin change and the background pattern will follow it. The problem with that solution is that the child view has to be large enough to cover the range of potential origins, which can be difficult to handle if the content area might be arbitrarily large.
You could generate an instance of your view again in the direction the user pans and add it to an NSMutableArray to be accessed and moved based on the offset of the world.
I have one UIView with slider and segment control as a subview.
I am using gesture control to handle rotation and scalling. Now while rotating uiview, the slider and segment control also get rotated.
I dont want rotation and scaling for subviews.
Please help me to sort this issue.
Thanks
Don't have your segmented control and slider as subviews of the scaled view.
If necessary, you could have a containing superview that contains the scaled view, segmented control and slider as subviews.
You could "counter-rotate" your subviews when you handle the gesture for rotating the UIView.
Create a CGAffineTransformRotate and apply it to your subview in case you do not want it to rotate:
[UIView beginAnimations:nil context:nil];
CGAffineTransform transform = CGAffineTransformRotate(subview.transform, radians);
subview.transform = transform;
[UIView commitAnimations];
After you apply the transformation to the subviews, they will be rotated accordingly until you reset the transformation to its default value.
In some of the applications, I have seen that we can drag a view outside of its position using two fingers(in smooth motion). We are also able to resize, rotate and move it further. And when I take my fingers off the screen it just resized(also rotates) and go backs to its original position by itself in a smooth motion.
How can I do this kind of animation? Is there any sample available? OR just telling me how the flow actually is will also be really helpful.
UIViews are animatable simply by setting properties.
[UIView animateWithDuration:0.5 animations:^{
myView.frame = CGRectMake(50, 50, 100, 200);
myView.layer.affineTransform = CGAffineTransformMakeRotation(M_PI);
}];
Look up animateWithDuration in the docs for more options and examples.
I have a custom UIView that implements drawRect to render itself with a gradient background and a 1-pixel black border around the edge, and some text.
In my parent view controller, I am attempting to animate my custom view from its original small size to full-screen, using this code:
[UIView beginAnimations:nil context:NULL];
CGRect screenRect = [[UIScreen mainScreen] applicationFrame];
CGRect detailRect = CGRectOffset(screenRect, 0, -screenRect.origin.y);
[dayDetail.view setFrame:detailRect];
[UIView commitAnimations];
This works, but drawRect in my custom view is only called once when the view is initially created. As a result the resizing just takes the original small image and blows it up to full screen, so the border of the full-size view is now many pixels wide instead of one, and the text gets expanded in size as well.
Is there any way to set this up so that drawRect is called continuously as the view is being animated from small to full-screen? Basically, I want my custom rendering code to handle the appearance of the view no matter what size it is at any point in time.
I've had the exact same problem and this is how I solved it:
dayDetail.view.contentStretch = CGRectMake(0.5, 0.5, 0.0, 0.0);
That will stretch the middle pixel only. Read the documentation to learn how to modify that behavior. You could certainly ask me, but reading the documentation is probably quicker. Besides, I would probably just quote the documentation.