iOS---界面的淡入淡出效果

简单的界面淡入淡出的效果--------主要的实现思路是改变界面的透明度

- (void)viewDidLoad {
    [super viewDidLoad];
    
    //要弹出的界面
    UIView *testView = [[UIView alloc] initWithFrame:self.view.frame];
    testView.backgroundColor = [UIColor blueColor];
    testView.tag = 1000;
    [self.view addSubview:testView];
    testView.alpha = 0.0;
 
    //创建当前界面点击手势
    UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(test)];
    [self.view addGestureRecognizer:tap];

    //创建淡出界面的点击手势
     UITapGestureRecognizer *tap2 = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(test2)];
    [testView addGestureRecognizer:tap2];
    
}

实现方法

- (void)test{

    //改变透明度即可实现效果
    [UIView animateWithDuration:0.5 animations:^{
       UIView *view = [self.view viewWithTag:1000];
        view.alpha = 1.0;
        [self.view layoutIfNeeded];
    }];
    
}

- (void)test2{
    
    [UIView animateWithDuration:0.5 animations:^{
        UIView *view = [self.view viewWithTag:1000];
        view.alpha = 0.0;
        [self.view layoutIfNeeded];
    }];
    
}

还有一种最简单的方式是：

   [UIView transitionWithView:self.view duration:0.5 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
        self.view.backgroundColor = [UIColor redColor];
    } completion:nil];