Hi all,
For the animation i used:
[UIView commitAnimation:#"anim" context:nil];
[UIView setAnumatioDuration:10];
imageView.center=CGPointMake(100,100);
[UIView commitAnimation];
The thing is that when i call with timer every 0.5 seconds:
CGRect rect=[[imageview.layer presentationLayer]frame];
CGPoint point=rect.origin;
NSLog(#"x:%f,y:%f",origin.x,origin.y);
I will always get x:100,y:100And I what i want to get is the true location on the view
while the imageview heading to (100,100)
10x a lot
Animations are updated on the presentation layer of a view. You can retrieve the values representing the current state of the image view during an animation by looking at this layer.
CGPoint center = [[imageView.layer presentationLayer] center];
Related
I have an app which intakes client details, built for iPad. When the user taps a UITextField towards the bottom half of the ViewController, the frame programatically shifts upwards so that the fields aren't hidden behind the keyboard. (I tried to implement a UIScrollView but just cannot seem to get it working.) The slight issue I'm having now is when the frame shifts up, you can vaguely see the black behind it. This isn't a huge issue because I have changed the animation time and the black background is barely visible, but I have a feeling there is a more elegant solution.
Here is my code to shift the frame:
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
// Animate frame up if lower textfields are tapped
if (([textField isEqual:_emailField]) || ([textField isEqual:_dobField]) || ([textField isEqual:_niNumField])) {
[UIView beginAnimations:nil
context:NULL];
[UIView setAnimationDuration:0.35f];
CGRect frame = self.view.frame;
frame.origin.y = -210;
[self.view setFrame:frame];
[UIView commitAnimations];
} else {
// Return frame to original position if other textfields are tapped
[self dismissKeyboard];
}
return YES;
}
- (void)dismissKeyboard {
[UIView beginAnimations:nil
context:NULL];
[UIView setAnimationDuration:0.15f];
CGRect frame = self.view.frame;
frame.origin.y = 0;
[self.view setFrame:frame];
[UIView commitAnimations];
}
Here is a brief screenshot of what I'm trying to describe. Left picture is the ViewController normally, right picture is when the frame has been shifted upwards. You can see (vaguely) almost in line with the second row of characters is where the frame stops.
I realise this doesn't seem like an issue because it is barely visible at all, but I have had to speed up the animation hiding the keyboard or else the frame drags behind and the black background becomes visible. I am wondering: is there a way to change this colour? Or is that something we don't have access to? If anyone can suggest a more elegant method for what I am trying to do, I'd gladly take a better solution. Thanks in advance.
Your UIViewController's view is added to the main UIWindow. So you should be able to achieve what you want by changing the UIWindow's background color.
In the UIApplicationDelegate:
self.window.backgroundColor = [UIColor whiteColor];
However, what you're doing isn't the best way to solve the problem of the keyboard covering up the text fields. You should use a UIScrollView or a UITableView to manage this view and use content insets to shift the view up or down.
I have a UIView and I want to get it's current frame while it's animated.
I am using a basic animation:
[UIView beginAnimations:#"MoveView" context:nil];
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
[UIView setAnimationDuration:3];
_testView.frame = CGRectMake(0, 100, 40, 40);
[UIView commitAnimations];
and I have a button which should add another UIView at the current position of the first one while animated, but when I press the button, it adds it to the end position of the animation...
Any suggestions?
Thank you in advance!
Most probably you're setting the newly added UIView properties based on the animated view's modelLayer. Let's try to setup the UIView properties based on the animated view's presentationLayer:
The layer object returned by this method provides a close approximation of the layer that is currently being displayed onscreen. While an animation is in progress, you can retrieve this object and use it to get the current values for those animations.
CALayer Class Reference
I have a tableView with textFields inside of them, and I have animation that slides the tableView up when the textFieldDidBeginEditing method is called. Here is my code:
- (void)textFieldDidBeginEditing:(UITextField *)textField {
self.headerView.alpha = 0.2;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.18];
[UIView setAnimationDelegate:self];
self.theTableView.frame = CGRectMake(0, 130, 320, 209);
[UIView commitAnimations];
}
The problem is that the animation happens whenever one of the cells is tapped, but I only want it to happen the first time a cell is tapped. So I was thinking that I should make an if statement that checks whether the tableView is at the (0, 130) coordinates. Does anyone know how I would do this?
For an exact comparison, CGPointEqualToPoint() will suffice. For a broader comparison (checking if the rect of the view contains the given point), CGRectContainsPoint() is perfect.
Of course, all of this is a little much. Subclass your view and keep a flag on it to track whether or not they've been slid up. Not only does it keep your code more self-contained, but it keeps the logic for the view out of your controller.
- (void)viewDidLoad
{
[super viewDidLoad];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:4];
[UIView setAnimationRepeatCount:50];
[UIView setAnimationRepeatAutoreverses:NO];
CGPoint abc =chem1.center;
abc.y= 480;
chem1.center=abc;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:4];
[UIView setAnimationRepeatCount:50];
[UIView setAnimationRepeatAutoreverses:NO];
CGPoint def =chem2.center;
def.y= 480 ;
chem2.center=def;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:4];
[UIView setAnimationRepeatCount:50];
[UIView setAnimationRepeatAutoreverses:NO];
CGPoint hij =nat1.center;
hij.y= 480;
nat1.center=hij;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:4];
[UIView setAnimationRepeatCount:50];
[UIView setAnimationRepeatAutoreverses:NO];
CGPoint klm =nat2.center;
klm.y= 480;
nat2.center=klm;
}
I'd really appreciate the help
There are two parts to your question: how to tap an animated image and how to drag an image.
How to tap an animated image.
Background
When you are animating a view (or more accurately its layer) the property that you change (in your case the position (by setting center)) is changed to its final value right away. If you only animate (like with a CABasicAnimation, then the properly might not change at all.
This means that if you try to tap the view (or layer) it will be at the position that you moved it to (its final position (despite any duration or repeat count of the animation).
Hit test a moving layer
To be able to hit test something that is moving you need to hit test against the presentationLayer of the layer of the view that you are trying to tap.
CGPoint touchPoint = [gestureRecognizer locationInView:[self view]];
if ([[[[self movingView] layer] presentationLayer] hitTest:touchPoint]) {
// Yeah, you hit the moving (animating) layer!
}
Now that the user has tapped a moving view (image in your case) you can begin to handle the drag.
How to drag an image
When you are dragging an image you move the layer to wherever the users finger is dragging the image.
Remove to animation that moves the view
First you should cancel the ongoing animation for that view (having a name for the animation enables you to cancel only one animation.
[[[self movingView] layer] removeAllAnimations];
Or if you have set a name to the movement animation.
[[[self movingView] layer] removeAnimationForKey:#"nameOfMovingAnimation"];
Move the view to the location of the users finger
Next you should (continuously) update the position of the view as the user moves its finger. You should not animate this since it will increase the time between the movement of the finger and the view and will make it seem like your application is lagging. Animating while dragging does not make it look smooth.
Note: since your question doesn't say what you want to do once the user are dragging the images or what happens when they drop them. I can't go much further in the explanation.
Need more help?
Search the web (or StackOverflow) for something like: "iOS drag view" and you will probably find more information about how to drag your imageViews.
Otherwise ask another question on StackOverflow once you have gotten this far (i.e. you can tap on the moving images and they stop moving).
Im currently working on an iPhone project. I want to enlarge dynamically an UILabel in Objective-C like this:
alt text http://img268.imageshack.us/img268/9683/bildschirmfoto20100323u.png
How is this possible? I thought I have to do it with CoreAnimation, but I didn't worked. Here is the code I tried:
UILabel * fooL = //[…]
fooL.frame = CGRectMake(fooL.frame.origin.x, fooL.frame.origin.y, fooL.frame.size.width, fooL.frame.size.height);
fooL.font = [UIFont fontWithName:#"Helvetica" size:80];
[UIView beginAnimations:nil context:nil];
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
[UIView setAnimationDelegate:self];
[UIView setAnimationDuration:0.5];
[UIView setAnimationBeginsFromCurrentState:YES];
fooL.font = [UIFont fontWithName:#"Helvetica" size:144]; //bigger size
fooL.frame = CGRectMake(20 , 44, 728, 167); //bigger frame
[UIView commitAnimations];
The problem with this code is that it doesn't change the fontsize dynamically.
All you need to do is apply an affine transform to the UILabel object.
CGFloat scaleFactor = 2.0f;
label.transform = CGAffineTransformMakeScale(scaleFactor, scaleFactor); // Enlarge by a factor of 2.
Scaling your label as suggested by others using the transform property will work great. One thing to keep in mind is that as the label gets larger, the font is not increasing, but just the rendered text, which means it will appear "fuzzier" as it gets larger.
Just scale your Label instead of changing the fontSize.
Try this method:
+ (void)setAnimationTransition:(UIViewAnimationTransition)transition
forView:(UIView *)view
cache:(BOOL)cache
Parameters:
transition
A transition to apply to view. Possible values are described in UIViewAnimationTransition.
view
The view to apply the transition to.
cache
If YES, the before and after images of view are rendered once and used to create the frames in the animation. Caching can improve performance but if you set this parameter to YES, you must not update the view or its subviews during the transition. Updating the view and its subviews may interfere with the caching behaviors and cause the view contents to be rendered incorrectly (or in the wrong location) during the animation. You must wait until the transition ends to update the view.
If NO, the view and its contents must be updated for each frame of the transition animation, which may noticeably affect the frame rate.
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.