iOS版; 如何缩放UIimageView（永久），然后移动它

Question

I've hit a wall here. I know how to move an Image using "CGAffineTransformMakeTranslation" and I also know how to scale an image using"CGAffineTransformMakeScale" but for the life of me, I can't seem to get one Image to do both of these and stay that way. It scales to the desired size for about a split second and then immediately reverts to its original size and moves to the desired location. What I need is for the image to get big, STAY big, and then move to a new location (while permanently staying its new size).

Here is what I've got going on in my .m file:

-(IBAction)PushZoomButton {

[UIWindow animateWithDuration:1.5
                 animations:^{
                     JustinFrame.transform = CGAffineTransformMakeScale(2.0, 2.0);
                     JustinFrame.transform = CGAffineTransformMakeTranslation(10.0, 10.0);}];



[UIWindow commitAnimations];}

Any help with this would be appreciated!

Answer 1

you can use CGAffineTransformConcat, for instance:

JustinFrame.transform = CGAffineTransformConcat(CGAffineTransformMakeScale(2.0, 2.0), CGAffineTransformMakeTranslation(10.0, 10.0));

You may need to adapt the translation to (5, 5) since you have doubled the scale

Answer 2

The second transform you set overrides the first one. You need to concat both transform actions into one, as Luis said. Another way of writing that would be:

CGAffineTransform transform = CGAffineTransformMakeScale(2.0, 2.0);
transform = CGAffineTransformTranslate(transform, 10, 10);
JustinFrame.transform = transform;

Answer 3

You may need to look into CoreAnimation, basically what UIView animation is controlling under the hood. If you set up a CAAnimation, then what you want to achieve is done with the fillMode property of the animation.

Here's some example code to make a UIView look like it's opening like a door (copy pasted some code I have, but perhaps you could modify it and find it useful):

- (void) pageOpenView:(UIView *)viewToOpen duration:(NSTimeInterval)duration pageTurnDirection:(PageTurnDirection) p{
// Remove existing animations before stating new animation
[viewToOpen.layer removeAllAnimations];

// Make sure view is visible
viewToOpen.hidden = NO;

// disable the view so it’s not doing anythign while animating
viewToOpen.userInteractionEnabled = NO;

float dir = p == 0 ? -1.0f : 1.0f;  // for direction calculations

// create an animation to hold the page turning
CABasicAnimation *transformAnimation = [CABasicAnimation animationWithKeyPath:@"transform"];
transformAnimation.removedOnCompletion = NO;
transformAnimation.duration = duration;
transformAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];

CATransform3D startTransform = CATransform3DIdentity;

if (p == NEXT_PAGE) {
    // orig values
    startTransform.m34 = 0.001f;
}else {
    // orig values
    startTransform.m34 = -0.001f;
}

// start the animation from the current state
transformAnimation.fromValue = [NSValue valueWithCATransform3D:startTransform];
// this is the basic rotation by 90 degree along the y-axis
CATransform3D endTransform = CATransform3DMakeRotation(3.141f/2.0f,
                                                       0.0f,
                                                       dir,
                                                       0.0f);
// these values control the 3D projection outlook

if (p == NEXT_PAGE) {
    endTransform.m34 = 0.001f;
    endTransform.m14 = -0.0015f;
}else {
    endTransform.m34 = -0.001f;  
    endTransform.m14 = 0.0015f;
}


transformAnimation.toValue = [NSValue valueWithCATransform3D:endTransform];


// Create an animation group to hold the rotation
CAAnimationGroup *theGroup = [CAAnimationGroup animation];

// Set self as the delegate to receive notification when the animation finishes
theGroup.delegate = self;
theGroup.duration = duration;
// CAAnimation-objects support arbitrary Key-Value pairs, we add the UIView tag
// to identify the animation later when it finishes
[theGroup setValue:[NSNumber numberWithInt:[(BODBookPageView *)viewToOpen pageNum]] forKey:@"animateViewPageNum"];  //STEPHEN: We set the tag to the page number
[theGroup setValue:[NSNumber numberWithInt: p] forKey:@"PageTurnDirection"]; 
[theGroup setValue:[NSNumber numberWithBool:YES] forKey:@"isAnimationMidpoint"];  // i.e. is this the first half of page-turning or not?

// Here you could add other animations to the array
theGroup.animations = [NSArray arrayWithObjects:transformAnimation,  nil];
theGroup.removedOnCompletion = NO;  // THIS LINE AND THE LINE BELOW WERE CRUCIAL TO GET RID OF A VERY HARD TO FIND/FIX BUG.
theGroup.fillMode = kCAFillModeForwards;  //  THIS MEANS THE ANIMATION LAYER WILL STAY IN THE STATE THE ANIMATION ENDED IN, THEREBY PREVENTING THAT ONE FRAME FLICKER BUG.
// Add the animation group to the layer
[viewToOpen.layer addAnimation:theGroup forKey:@"flipViewOpen"];

}