Question

我希望在视图加载时倒计时图像。为此目的，我在视图加载时延迟了所有函数。在视图加载时我做了

- (void)viewDidLoad
{
 //-=-=-=-=-=-=-=-=-=-=-=-=-=Count Down Numbers animation-=-=-=-=-=-=-=-=-=-
    NumImageView.animationImages = [NSArray arrayWithObjects:[UIImage imageNamed:@"03.png"],         [UIImage imageNamed:@"02.png"],[UIImage imageNamed:@"01.png"], nil];
    NumImageView.animationDuration =4;

    [numView addSubview:NumImageView];

    [NumImageView startAnimating]; 
.......//remaining code

}

这里我在numView上删除了NumImageView UIImageView。

但未获取所有图像.3和1动画显示剩余的2张图像。实际上这是正确的过程或使用NSThread是正确的过程，但我现在不知道如何使用NSThread。

Answer 1

你可能想做这样的事情，我不知道你的实施细节，但我相信你可以搞清楚

//add all images into an array with
NSArray *NumImageView = @{img1, img2, img3, img4}; //these are UIImageViews that you have made previously

for(int i = 0; i < NumImageView.count; i++){
     [numView addSubview:NumImageView[i]]; //add all images
     NumImageView[i].hidden = true; //make them hidden initially
}

for(int i = 0; i < NumImageView.count; i++){

    [UIView animateWithDuration:1.0 delay:i*1.0 options:UIViewAnimationOptionCurveLinear animations:^{
        NumImageView[i].hidden = false; //unhide when it starts aniamting

        //animate image coming in

    } completion:^(BOOL finished) {
        UIImageView *image = NumImageView[i];
        [image removeFromSuperView]; //remove current number
    }];
}

Answer 2

你也可以通过动画块实现这一点，动画块在达到完成时移动到下一个动画，就像在这个方法中一样：

- (void)animateCountDown
{
    //first add numImageView
    [numView addSubview:numImageView];
    //add first image
    numImageView.image = [UIImage imageNamed:@"03.png"];
    [UIView animateWithDuration:1.0 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^
    {
        numImageView.image = [UIImage imageNamed:@"02.png"];
    }
                     completion:^(BOOL finished)
                     {
                         [UIView animateWithDuration:1.0 delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^
                          {
                              numImageView.image = [UIImage imageNamed:@"01.png"];
                          }
                                          completion:^(BOOL finished)
                                          {
                                              //start whatever after countdown
                                           }];
                     }];
}

然后在您的viewDidLoad中调用此内容[self animateCountDown];

另一种方法是使用NSTimer。我做了一个例子，你可以看到如何使用你认为合适的。在此示例中，NSTimer正在调用countMethod，这会将count integer递减，将UIImage设置为UIImageView，countMethod也会检查count integer如果invalidate低于1，那么可以NSTimer {{1}}，并且您可以调用方法来启动应用程序的其余部分。

听起来很多，但是看一下这个截图，一切都很清楚：

NSTimerexample

Answer 3

试试这个

-(void)viewdidload
{
 [NSThread detachNewThreadSelector:@selector(animateImages) toTarget:self withObject:nil]
}

-(void)animateImages
{
//-=-=-=-=-=-=-=-=-=-=-=-=-=Count Down Numbers animation-=-=-=-=-=-=-=-=-=-
    NumImageView.animationImages = [NSArray arrayWithObjects:[UIImage imageNamed:@"03.png"],         [UIImage imageNamed:@"02.png"],[UIImage imageNamed:@"01.png"], nil];
    NumImageView.animationDuration =4;

    // repeat the annimation forever
    NumImageView.animationRepeatCount = 1;
   [NumImageView startAnimating];
    [numView addSubview:NumImageView];


.......//remaining code
}

加载视图时倒计时图像

3 个答案: