iOS-使用NSTimer，UIImageView僅在第一次更新

Question

所有

當我使用NSTimer完成任務時，遇到了一些問題。 我需要一些幫助，謝謝。

這是問題所在。

當我使用NSTimer在UIImageView上顯示動畫時。 但是UIImageView只是在我第一次使用xcode在iphone4s中運行代碼時更新。 當UIImageView再次出現時，它不會更新圖像內容。 我已經檢查了日志，每次都調用計時器，並且在運行時覆蓋了代碼。

NSTimer：

if (networkStatusTimer == nil) {
        networkStatusTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(getcurrentNetworkDelayStatus) userInfo:nil repeats:YES];

networkStatusImageView初始化部分：

- (UIImageView *)networkStatusImageView
{
    if (nil == _networkStatusImageView) {
        CGRect rect = CGRectMake(246, 12, 24, 8);
        _networkStatusImageView = [[UIImageView alloc]initWithFrame:rect];
        _networkStatusImageView.contentMode = UIViewContentModeRight | UIViewContentModeTop;

        UIImageView *img1 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_redsolid_1X"]];
        UIImageView *img2 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_redhollow_1x"]];
        UIImageView *img3 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"talk_icon_whitehollow_1x"]];

        img2.left = img1.right;
        img3.left = img2.right;

        [_networkStatusImageView setNeedsDisplay];
        [_networkStatusImageView addSubview:img1];
        [_networkStatusImageView addSubview:img2];
        [_networkStatusImageView addSubview:img3];
    }
    return _networkStatusImageView;
}

選擇器代碼：

- (void) getcurrentNetworkDelayStatus {
    currentNetworkDelayTime = 0;
    [_networkStatusImageView removeAllSubviews];
    UIImageView *img1 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_redhollow_1x"]];
    UIImageView *img2 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_redhollow_1x"]];
    UIImageView *img3 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_redhollow_1x"]];

    dispatch_async(dispatch_get_main_queue(), ^{
    if (currentNetworkDelayTime == 0) { 
        if (currentISRed) {
            img1.image = [UIImage imageNamed:@"talk_icon_redhollow_1x"];
            img2.image = [UIImage imageNamed:@"talk_icon_redhollow_1x"];
            img3.image = [UIImage imageNamed:@"talk_icon_redhollow_1x"];
        } else {    // 顯示紅色實心
            img1.image = [UIImage imageNamed:@"talk_icon_redsolid_1X"];
            img2.image = [UIImage imageNamed:@"talk_icon_redsolid_1X"];
            img3.image = [UIImage imageNamed:@"talk_icon_redsolid_1X"];
        }
        currentISRed = !currentISRed;
    } else if(currentNetworkDelayTime > 0 && currentNetworkDelayTime <= 500){ 
        img1 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_greensolid1X"]];
        img2 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_greensolid1X"]];
        img3 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"talk_icon_greensolid1X"]];
    } else if(currentNetworkDelayTime > 500 && currentNetworkDelayTime <= 3000){   
        img1 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_greensolid1X"]];
        img2 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_greensolid1X"]];
        img3 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"talk_icon_greenhollow_1x"]];
    } else if (currentNetworkDelayTime > 3000){
        img1 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_greensolid1X"]];
        img2 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"talk_icon_greenhollow_1x"]];
        img3 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"talk_icon_greenhollow_1x"]];
    }

    img2.left = img1.right;
    img3.left = img2.right;

    [img1 setNeedsDisplay];
    [img2 setNeedsDisplay];
    [img3 setNeedsDisplay];
    [_networkStatusImageView setNeedsDisplay];

    [_networkStatusImageView addSubview:img1];
    [_networkStatusImageView addSubview:img2];
    [_networkStatusImageView addSubview:img3];
    });
}

Answer 1

每次調用該函數時，請將currentNetworkDelayTime設置為0。這意味着僅：

if (currentNetworkDelayTime == 0) { 
    if (currentISRed) {
        img1.image = [UIImage imageNamed:@"talk_icon_redhollow_1x"];
        img2.image = [UIImage imageNamed:@"talk_icon_redhollow_1x"];
        img3.image = [UIImage imageNamed:@"talk_icon_redhollow_1x"];
    } else {    // 顯示紅色實心
        img1.image = [UIImage imageNamed:@"talk_icon_redsolid_1X"];
        img2.image = [UIImage imageNamed:@"talk_icon_redsolid_1X"];
        img3.image = [UIImage imageNamed:@"talk_icon_redsolid_1X"];
    }
    currentISRed = !currentISRed;
}

被叫。 因此，您需要更改行currentNetworkDelayTime = 0; 到currentNetworkDelayTime++;

而且您不必每次都將圖像添加到當前的UIView ，只需在ex中一次創建它們即可。 viewDidLoad並為其創建全局變量。

完成此操作后，請添加此方法以縮短代碼：

-(void)changeView:(NSArray *)strArray {
    NSArray *viewArray = [[NSArray alloc] initWithObjects:view1, view2, view3, nil];
    for (int a = 0; 0 < 3; a++) {
        UIImageView *img = viewArray[a];
        img.image = [UIImage imageNamed:strArray[a]];
        [img setNeedsDisplay]; // If you really want to do this.
    }
}

並這樣稱呼它

[self changeView:[[NSArray alloc] initWithObjects:@"Image_for_img1.suffix", @"Image_for_img2.suffix", @"Image_for_img3.suffix", nil]];

Answer 2

我已經在計算機上測試了您的代碼，並使其正常運行。

在頭文件中：

@property(nonatomic,strong)UIImageView *networkStatusImageView;

在viewDidLoad中：

[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(test) userInfo:Nil repeats:YES];
self.networkStatusImageView = [self networkStatusImageView];
[self.view addSubview:self.networkStatusImageView];

函數networkStatusImageView：

- (UIImageView *)networkStatusImageView
{
if (nil == _networkStatusImageView) {
    CGRect rect = CGRectMake(0, 0, 300, 50);
    _networkStatusImageView = [[UIImageView alloc]initWithFrame:rect];
    _networkStatusImageView.contentMode = UIViewContentModeRight | UIViewContentModeTop;

    for (int a = 0; a < 3; a++) {
    UIImageView *img = [[UIImageView alloc] initWithFrame:CGRectMake(100*a, 0, 100, 50)];
    [img setBackgroundColor:[UIColor blueColor]];
    [_networkStatusImageView addSubview:img];
}
}
return _networkStatusImageView;
}

功能測試：

-(void)test {
int currentNetworkDelayTime = 0;
BOOL currentISRed = NO;
NSArray *subViews = [self.networkStatusImageView subviews];
UIImageView *img1 = [subViews objectAtIndex:0];
UIImageView *img2 = [subViews objectAtIndex:1];
UIImageView *img3 = [subViews objectAtIndex:2];
if (currentNetworkDelayTime == 0) {
    if (currentISRed) {
        [img1 setBackgroundColor:[UIColor redColor]];
        [img2 setBackgroundColor:[UIColor redColor]];
        [img3 setBackgroundColor:[UIColor redColor]];
    } else {
        [img1 setBackgroundColor:[UIColor greenColor]];
        [img2 setBackgroundColor:[UIColor greenColor]];
        [img3 setBackgroundColor:[UIColor greenColor]];
    }
}
}

我使用背景顏色而不是圖像，因為我不想制作圖像進行測試，只需將其更改為setImage: 。

Answer 3

我已經解決了我的問題，下面是解決方案：

我仔細檢查了問題，並創建了三個UIImage字段var。 下面：

@property (nonatomic, weak) UIImage *imgFile1;
@property (nonatomic, weak) UIImage *imgFile2;
@property (nonatomic, weak) UIImage *imgFile3;

並將它們與xib圖像資源鏈接。

該功能的實現不好，我計划在下一個版本中重新實現它，內存分配和釋放過多，可以刪除一些分配和釋放以提高代碼效率。

謝謝大家的幫助。