I rotate a view by 45 degree on every dragging. Here is my code. Problem here is that the view is rotated only once. After that there is no rotation. What will be the reason? Any help
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
CGContextRef context = UIGraphicsGetCurrentContext();
[UIView beginAnimations:nil context:context];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:0];
dialView.transform = CGAffineTransformMakeRotation(45* M_PI/180);
[UIView commitAnimations];
}
You can also use CGAffineTransformRotate to rotate from its present transform, as in:
dialView.transform = CGAffineTransformRotate(dialView.transform, 45 * M_PI / 180);
The rotation is always relative to 0. If you rotate to x several times it will rotate only the first time.
If you want to rotate 45 everytime you call that code, you will need to have counter and it would look like this:
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
step++;//You are supposed to keep this variable global.
CGContextRef context = UIGraphicsGetCurrentContext();
[UIView beginAnimations:nil context:context];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:0];
dialView.transform = CGAffineTransformMakeRotation(45*step* M_PI/180);
[UIView commitAnimations];
}
Related
i have two views and one viewcontroller: one contains UIImageView with image, second have touchesBegan and touchesEnded method:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[viewcontroller moveMethod];
}
How to make moveMethod method to make the animation (eg. moving the x-axis) repeat smoothly until I stop to push the view?
try this code to move your view on x-axis
CGRect frame=view.frame;
frame.origin.x=frame.origin.x+200;
[UIView beginAnimations:#"" context:nil];
[UIView setAnimationDuration:2];
[UIView setAnimationDelegate:self];
view.frame=frame;
[UIView commitAnimations];
I have an image of a fish - If the user touches the screen I want the fish to "look" at the touched point and move there. If the touch has been moved i want the fish constantly following the touch.
How can I do that?
would be something like this:
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *tap = [touches anyObject];
CGPoint pointToMove = [tap locationInView:self.view];
CGFloat xdiff = pointToMove.x-myFish.center.x;
CGFloat ydiff = pointToMove.y-myFish.center.y;
if (!CGRectContainsPoint(myFish.frame, pointToMove)) {
CGFloat angle = 0;
if (xdiff) {
if (xdiff>0) {
angle = atanf(ydiff/xdiff);
} else {
angle = M_PI + atanf(ydiff/xdiff);
}
}
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.3f];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationCurve:UIViewAnimationCurveLinear];
myFish.transform = CGAffineTransformMakeRotation(angle);
[UIView commitAnimations];
}
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1.0f];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationCurve:UIViewAnimationCurveLinear];
myFish.center = pointToMove;
[UIView commitAnimations];
}
and you probably want to implement these too:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
EDIT: updated code, now the rotation is done in a separate animation, so that the fish rotates faster than he swims.
I`m using a simple Textview in an tabbased application to display some text :) I figerd out how to change the text animated using the following code:
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint currentTouchPosition = [touch locationInView:self];
// To be a swipe, direction of touch must be horizontal and long enough.
if (fabsf(startTouchPosition.x - currentTouchPosition.x) >= HORIZ_SWIPE_DRAG_MIN &&
fabsf(startTouchPosition.y - currentTouchPosition.y) <= VERT_SWIPE_DRAG_MAX)
{
// It appears to be a swipe.
if (startTouchPosition.x < currentTouchPosition.x){
NSString *string = [[NSString alloc]initWithFormat:#"..."];
self.text = string;
}
else{
CGContextRef context = UIGraphicsGetCurrentContext();
[UIView beginAnimations:nil context:context];
//[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:[self superview] cache:YES];
[UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView:[self superview] cache:YES];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:0.5];
[[self superview] exchangeSubviewAtIndex:0 withSubviewAtIndex:1];
[UIView commitAnimations];
[self displayNewText];
}
}
However there is now "slide transition" defined in UIViewAnimationTransition. I know about paging, but I don`t want to use this. Is there an other possibility to have an horizontal slide animation when detecting a horizontal swipe?
I think you are almost there. Intercept touchesMoved:withEvent method just like in your current code and update the visible area of the UIScrollView object.
I hope you don't have to detect touches for your requirement use UIScrollView as parent view for UITextView.
scroll=[[UIScrollView alloc]initWithFrame:CGRectMake(0,40, 320,200)];
[scroll setContentSize:CGSizeMake(640, 200)];
Or if you want to animate the view you can use affine transforms.
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1];
someview.transform=CGAffineTransformMakeTranslation(-100, 0);
[UIView commitAnimations];
I want to create an animation that moves and rotates a UIView at the same time. I tried the following code:
[UIView beginAnimations:#"MoveAndRotateAnimation" context:nil];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:kAnimationDuration];
myView.frame = newFrame;
myView.transform = CGAffineTransformMakeRotation(0.4);
[UIView commitAnimations];
The result is, that after the animation has finished the view is drawn incorrectly (some parts are not visible anymore). If I only change the frame OR the transformation for the animation, the view draws correctly. The problem only occurs if I set both the frame and transformation.
What would be the correct way to animate moving and rotating of a view at the same time?
You can't use frame, bounds, or center if you are also animating things like rotation. You need to use CGAffineTransforms for everything and concatenate them together. Like so:
CGAffineTransform transform = CGAffineTransformMakeTranslation(100,100);
transform = CGAffineTransformRotate(transform, 0.4);
[UIView beginAnimations:#"MoveAndRotateAnimation" context:nil];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:kAnimationDuration];
myView.transform = transform;
[UIView commitAnimations];
Try doing it this way: (Moving left and rotating, just for example)
[UIView beginAnimations:#"MoveAndRotateAnimation" context:NULL];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:kAnimationDuration];
CGPoint center = CGPointMake(-200, self.view.center.y);
self.view.transform = CGAffineTransformMakeRotation(-0.5);
self.view.center = center;
[UIView commitAnimations];
The center point locations would be the point you wish to make the view move, of course.
The problem is probably with your new frame size as compared to original frame size. View frame is a bit tricky when you rotate a frame:
Frame is in superviews coordinate system. So, when you rotate a rectangle, the new frame will be the smallest rectangle in superview's coordinate system which contains the view.
e.g. if you have a square view with frame size of (100*100) and rotate it by 45 degrees your new frame would have a size of (141*141) and if you set the frame to have a size of (100*100) you'll cut part of your view.
Look at here for better understanding of how view frame works.
You need to do this:
#pragma mark (Woblling animation)
CGAffineTransform leftWobble = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(-10.0));
CGAffineTransform rightWobble = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(10.0));
self.view .transform = leftWobble; // starting point
[UIView beginAnimations:#"wobble" context:self.view ];
[UIView setAnimationRepeatAutoreverses:YES]; // important
[UIView setAnimationRepeatCount:11];
[UIView setAnimationDuration:1.00];
//[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.view cache:YES];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector(wobbleEnded:finished:context:)];//should be same as written
self.view .transform = rightWobble; // end here & auto-reverse
[UIView commitAnimations];
and then implement these methods. They are necessary to keep your view in the same position after rotation.
- (void) wobbleEnded:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context
{
if ([finished boolValue]) {
UIView* item = (UIView *)context;
item.transform = CGAffineTransformIdentity;
}
}
Use this method if you are using navigation and when you navigate from one view to another, then your view would be at the same place.else leave this method:
- (void)viewWillAppear:(BOOL)animated
{
UIView* item = self.view;
item.transform = CGAffineTransformIdentity;
}
I had the same problem but did some experiments and came up with this solution.
I have a telephone wheel. On the touchend, it goes to his position with an animation.
Until the angle is less than 180°, it returns clockwise. No problem, with this code :
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView beginAnimations:nil context:NULL];
[UIViewsetAnimationDuration:0.5];
wheel.transform = CGAffineTransformIdentity;
[UIView commitAnimations];
}
But It goes wrong after that and continue to rotate for a complet turn.
I tried to make to animations like this :
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.2];
wheel.transform = CGAffineTransformRotate(wheel.transform, degreesToRadians(-130));
[UIView commitAnimations];
[self performSelector:#selector(animatewheelViewToCenter) withObject:nil afterDelay:0.3];
}
- (void)animatewheelViewToCenter{
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView beginAnimations:nil context:NULL];
[UIViewsetAnimationDuration:0.3];
wheel.transform = CGAffineTransformIdentity;
[UIView commitAnimations];
}
It works, but the animation isn't fluid ; the change is visible.
I'm not sure what the state is when touchesEnded (in terms of rotation) and I'm assuing you chose degreesToRadians(-130) to try and do it partially and expect the next method to do the rest. This should be a better solution that hopefully yields the result you're expecting. I'm not sure what cadran is or why you're rotating that, so I'll just rotate the wheel.
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.2];
wheel.transform = CGAffineTransformMakeRotation(degreesToRadians(-130));
// I would recommend that the degrees you rotate be half of whatever your rotation is.
// this would make the wheel rotate to the home position more evenly
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector(animatewheelViewToCenter:finished:context:)];
[UIView commitAnimations];
}
- (void)animatewheelViewToCenter:(NSString *)animationID finished:(NSNumber *)finished context:(id)context {
[UIView setAnimationBeginsFromCurrentState:YES]; // you might need to make this NO
[UIView beginAnimations:nil context:NULL];
[UIViewsetAnimationDuration:0.2];
wheel.transform = CGAffineTransformIdentity;
[UIView commitAnimations];
}
EDIT: Actually, I would probably make the rotation (in the example -130 degrees) slightly more than what half would be, because CGAffineTransformIdentity is gonna take the shortest path to go back to regular, so if you go exactly 1/2 way, it may not go the correct direction (clockwise or counter-clockwise) that you want.