I want to animate a view to fade in when it's added as subview, and want it to fade out when it's removed from the superview. What is the best way to do this?
Set the alpha to zero before animating, then animate the alpha to one.
[fadingView setAlpha:0.0];
[containerView addSubview:fadingView];
[UIView beginAnimations:nil context:nil];
[fadingView setAlpha:1.0];
[UIView commitAnimations];
Before removing the view, just animate the alpha back to zero.
Related
I need to add a UIDatePicker subview on a button click to my main view.
How can I add the view with animation such that the subview flips in from the top of the main view and on removing ,undergoes the reverse animation ? I know the subview can be added in a frame that is outside the visible area of the view and then moving it to visible area using CABasicAnimation will be abetter choice. So need help regarding the animation block that I should use.
Thanks in advance
Try this bellow code... here if yourView default frame with origin y = -500 then try bellow code on any UIButton click event.. also set frame which you want
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.75];
[UIView setAnimationDelegate:self];
CGRect frame = yourView.frame;
frame.origin.y = frame.origin.y + 500; // give any value for display yourView
yourView.frame = frame;
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:yourView cache:YES];
[UIView commitAnimations];
Use CATransaction for animation.
I want to be able to fade in a sub view. Is there a way to animate that so that when my subview gets added it fades in and not just is all of a sudden pops up there. I know I could get several instances of my imageview with different alphas and then animate it that way but isn't there an easier way?
Yes, you can animate the view without needing different images. The below code will fade your view in over 0.3 seconds.
[myView setAlpha:0.0];
[myView setHidden:NO];
[UIView animateWithDuration:0.3 animations:^{
[myView setAlpha:1.0];
}];
You need only one instance. UIView.alpha can be animated.
You can set the alpha to 0 before adding the subview, and after your addSubview, you make an animation, like that:
yourView.alpha = 0.0f;
[self.view addSubview:yourView];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5f];
yourView.alpha = 1.0f;
[UIView commitAnimations];
I have a Custom view. This custom view has two UIImageViews - imageview1 and imageview2.
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:2.00];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector(transitionDidStop:finished:context:)];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self cache:YES];
if(frontVisible) {
[imageview1 removeFromSuperview];
[self addSubview: imageview2];
}
else {
[imageview2 removeFromSuperview];
[self addSubview: imageview1];
}
frontVisible = !frontVisible;
[UIView commitAnimations];
The image changes from imageview1 to imageview2 and viceversa but I dont get the flip effect. Instead I see the fading out of one image as the other appears.
Not really sure but I checked the documentation and found this:
Discussion
If you want to change the appearance of a view during a transition—for example, flip from one view to another—then use a container view, an instance of UIView, as follows:
Begin an animation block.
Set the transition on the container view.
Remove the subview from the container view.
Add the new subview to the container view.
Commit the animation block.
So it says you have to create a container view in order to make it work properly.
The reason you're not getting the curl transition to work is because the curl transition does not work in the simulator. It shows up as a fade instead.
how can I implement the animation we see in the iPhone Music app's coverflow screen? when you click on a small view, it flips and scales up to another view? how can I do this? I can use core animation to flip and scale a view, but how can I do the transition to another view? thanks
You need an UIView as Container for the two UIViews (frontside/backside) and then remove/add these from/to the container as subviews while doing the animations in between:
UIView *flipContainer;
UIView *frontSide;
UIView *backSide;
//...
-(void)turnUp
{
[backSide removeFromSuperview];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1.0];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:flipContainer cache:YES];
[UIView setAnimationDuration:1.0];
CGAffineTransform transform = CGAffineTransformMakeScale(1.2, 1.2);
flipContainer.transform = transform;
[UIView commitAnimations];
[flipContainer addSubview:frontSide];
}
-(void)turnDown
{
[frontSide removeFromSuperview];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1.0];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:flipContainer cache:YES];
[UIView setAnimationDuration:1.0];
CGAffineTransform transform = CGAffineTransformMakeScale(1, 1);
flipContainer.transform = transform;
[UIView commitAnimations];
[flipContainer addSubview:backSide];
}
I'm trying the exact code you are doing - I get a zoom effect but no turn over. The only difference is that right before the turnUp code I add the flipContainer (with back showing) so then it can be flipped over.
// construct animation container
self.flipContainer = [[FlipContainer alloc] init];
[self.flipContainer.view setFrame:CGRectMake(clickedSquareX, clickedSquareY, 200, 200)];
[self.flipContainer.view addSubview:self.backside.view];
// add animation container
[self.myParentView.view addSubview:self.flipContainer.view];
// PROCEED to your turnUp code
The reason I'm doing this is I have a bunch of images in a horizontal UIScrollView and so to 'simulate' a 200x200 image flipping over and zooming to show detail I add my flipContainer with the backside showing the exact image over the exact spot of the pressed image. It should work shouldn't it? A bit confusing to me is the first line of your turnUp code you do:
[backSide removeFromSuperview];
..which would remove the view I just added.
I'm not sure if this is the right spot to put this question in - sorry if it isn't!
I have a nice and easy "zoom" animation for a view, which starts as a dot and animates up to full screen size:
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:1.0];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
myView.frame = CGRectMake(0,0,320,480);
myView.transform = CGAffineTransformIdentity;
[UIView commitAnimations];
So far so good :-)
The problem is that when I add subviews to myView, to my surprise, they do not follow their superview's animation scheme!?!?
Btw. subviews are currently added as usual in MyView's initWithFrame. I tried to set their transform property to CGAffineTransformIdentity bu it did not help.
So, what needs to be done to allow a subview of myView to also animate in a nice "zoom" fashion together with its superview?
Thanks in advance!
/John
I just ran in to the same problem, and the solution was surprisingly easy. Whereas modifying the frame size only affects the current view, not the subviews (as you noticed), the transform property applies to the subviews as well.
I'm trying to do the reverse of what you're doing (have a subview that appears to 'drop' on to the top of an existing view when displayed, rather than zoom from the center). This code works for me:
self.transform = CGAffineTransformMakeScale(2,2);
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.25];
self.transform = CGAffineTransformMakeScale(1,1);
self.alpha = 1.0;
[UIView commitAnimations];
Try setting self.transform to CGAffineTransformMakeScale(0,0) before beginning the animation, and set it back to (1,1) before committing. Don't modify the frame at all - leave it at the size you want the view to have after the animation completes.
You can always use the auto-sizing in the interface builder . This way you can specify the left/margin which you don't want to change and the axis along which you want the particular sub-view to resize to .