当用户从屏幕右侧拖动手指时，我想执行翻转动画。动画的状态应该受到拖动长度的影响，并且不应该自动工作。
我用过这样的东西：
if (transitionBegan) {
flipTransition = CATransform3DIdentity;
flipTransition.m34 = 1.0 / -500;
flipTransition = CATransform3DRotate(flipTransition, degree * M_PI / 180.0f,0.0f, 1.0f, 0.0f);
self.view.layer.transform = flipTransition;
}
但是现在不知道怎么实现视图之间的转换，让视图A消失，视图B出现。
你能帮助我吗？
You can write a gesture recognizer that does the transform for you. For example, assuming you're able to flip both left and right, you could do something like the following. But the idea is that you transform the current view if you're less than half way through the flip, and transform the next view if more than half way through it:
- (void)handlePan:(UIPanGestureRecognizer *)gesture
{
static UIView *currentView;
static UIView *previousView;
static UIView *nextView;
if (gesture.state == UIGestureRecognizerStateBegan)
{
// Set the three view variables here, based upon the logic of your app.
// If there is no `previousView` or `nextView`, then set them to `nil`
// as appropriate.
// I happen to be choosing views for child view controllers for my
// custom container, but I'll spare you that in case you're not using
// custom container controller.
}
// lets set the "percent" rotated as the percent across the screen the user's
// finger has travelled
CGPoint translation = [gesture translationInView:gesture.view.superview];
CGFloat percent = translation.x / gesture.view.frame.size.width;
CGFloat rotationPercent = percent;
// let's use the var to keep track of which view will be rotated
UIView *viewToTransform = nil;
if (percent < -0.5 && nextView)
{
// if user has moved finger more than half way across the screen to
// the left, and there is a `nextView`, then we're showing the second
// half of flip to the next screen
currentView.hidden = YES;
nextView.hidden = NO;
previousView.hidden = YES;
rotationPercent += 1.0;
viewToTransform = nextView;
}
else if (percent > 0.5 && previousView)
{
// if user has moved finger more than half way across the screen to
// the right, and there is a `previousView`, then we're showing the second
// half of flip to the previous screen
currentView.hidden = YES;
nextView.hidden = YES;
previousView.hidden = NO;
rotationPercent -= 1.0;
viewToTransform = previousView;
}
else if ((percent < 0 && nextView) || (percent > 0 && previousView))
{
// otherwise we're in the first half of the flip animation, so we're
// showing the `currentView`
currentView.hidden = NO;
nextView.hidden = YES;
previousView.hidden = YES;
viewToTransform = currentView;
}
// do the flip `transform`
CATransform3D transform = CATransform3DIdentity;
transform.m34 = 1.0 / -800;
viewToTransform.layer.transform = CATransform3DRotate(transform, M_PI * rotationPercent, 0.0, 1.0, 0.0);
// if we're all done, let's animate the completion (or if we didn't move far enough,
// the reversal) of the pan gesture
if (gesture.state == UIGestureRecognizerStateEnded ||
gesture.state == UIGestureRecognizerStateCancelled ||
gesture.state == UIGestureRecognizerStateFailed)
{
// I'm personally using an index of my custom container child views, so I'm
// just updating my index appropriately; your logic may obviously differ
// here.
if (percent < -0.5 && nextView)
self.currentChildIndex++;
else if (percent > 0.5 && previousView)
self.currentChildIndex--;
// and animate the completion of the flip animation
[UIView animateWithDuration:0.25
delay:0.0
options:UIViewAnimationOptionCurveEaseInOut
animations:^{
previousView.transform = CGAffineTransformIdentity;
currentView.transform = CGAffineTransformIdentity;
nextView.transform = CGAffineTransformIdentity;
}
completion:NULL];
}
}
您应该能够在UIPanGestureRecognizer（正在监听手指拖动的手势识别器）的帮助下做到这一点，您将能够获得 Pan 的长度，并从那里计算您CATransform3D的 -based 平移和缩放跟随进度的平移。
（内置动画在那里没用，你必须在CoreAnimation这里使用，它很有趣，我可以告诉你;-)）
使用UIView animateWithDuration: animations: completion:方法将当前视图设置为动画到过渡点，然后在完成块中删除当前视图，添加新视图并在新视图上启动另一个类似的动画。