Question

如何在iphone中更改视图时解散动画？

溶解效果：一个视图正在改变另一个视图而没有任何移动。

非常感谢您的帮助！

Answer 1

您正在寻找的动画是：

[UIView animateWithDuration: 1.0
                 animations:^{
                     view1.alpha = 0.0;
                     view2.alpha = 1.0;
                 }];

使用该动画的更完整的解决方案可能是：

- (void) replaceView: (UIView *) currentView withView: (UIView *) newView
{
    newView.alpha = 0.0;
    [self.view addSubview: newView];

    [UIView animateWithDuration: 1.0
                     animations:^{
                         currentView.alpha = 0.0;
                         newView.alpha = 1.0;
                     } 
                     completion:^(BOOL finished) {
                         [currentView removeFromSuperview];
                     }];
}

Answer 2

您还可以在ios5及更高版本中使用UIViewAnimationOptionTransitionCrossDissolve ...

[UIView transitionFromView:currentView
                    toView:nextView
                  duration:2
                   options:UIViewAnimationOptionTransitionCrossDissolve 
                completion:^(BOOL finished) {
                    [currentView removeFromSuperview];
                    }];

Answer 3

UIView有一个名为transition(from:to:duration:options:completion:)的方法，它具有以下声明：

class func transition(from fromView: UIView, to toView: UIView, duration: TimeInterval, options: UIViewAnimationOptions = [], completion: ((Bool) -> Void)? = nil)

使用给定参数在指定视图之间创建过渡动画。

您可以传递给UIViewAnimationOptions的众多transition(from:to:duration:options:completion:)参数中有transitionCrossDissolve。

transitionCrossDissolve有以下声明：

static var transitionCrossDissolve: UIViewAnimationOptions { get }

从一个视图溶解到下一个视图的转换。

以下Swift 3 Playground代码显示了如何使用UIViews和transition(from:to:duration:options:completion:)在具有交叉溶解过渡的两个transitionCrossDissolve之间切换：

import UIKit
import PlaygroundSupport

class ViewController: UIViewController {

    let firstView: UIView = {
        let view = UIView(frame: CGRect(x: 50, y: 50, width: 100, height: 100))
        view.backgroundColor = .red
        return view
    }()
    let secondView: UIView = {
        let view = UIView(frame: CGRect(x: 50, y: 50, width: 100, height: 100))
        view.backgroundColor = .blue
        return view
    }()

    override func viewDidLoad() {
        super.viewDidLoad()

        view.backgroundColor = .white
        view.addSubview(firstView)

        let tapGesture = UITapGestureRecognizer(target: self, action: #selector(toggle(_:)))
        view.addGestureRecognizer(tapGesture)
    }

    func toggle(_ sender: UITapGestureRecognizer) {
        let presentedView = view.subviews.first === firstView ? firstView : secondView
        let presentingView = view.subviews.first !== firstView ? firstView : secondView        
        UIView.transition(from: presentedView, to: presentingView, duration: 1, options: [.transitionCrossDissolve], completion: nil)
    }

}

let controller = ViewController()
PlaygroundPage.current.liveView = controller

Answer 4

[UIView beginAnimations: @"cross dissolve" context: NULL];
[UIView setAnimationDuration: 1.0f];
self.firstView.alpha = 0.0f;
self.secondView.alpha = 1.0f;
[UIView commitAnimations];

如何在iphone上更改视图时解散动画？

4 个答案: