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按下按钮时内存泄漏

memory xcode objective-c ios

Chandrasekaran Dinesh · 技术社区 · 9 年前

我正在尝试制作一个简单的应用程序,用户可以在其中浏览笔记,然后做一个测试。我将这些笔记作为图像呈现,图像将分配给 UIImageView 向用户展示。

- (void)viewDidLoad {
    UIColor *colourForNavigationBar = [self colorWithHexString:@"919D9F"];
    [[UINavigationBar appearance] setBarTintColor:colourForNavigationBar];
    UIColor *colourForBackground = [self colorWithHexString:@"F0F3F4"];
    self.view.backgroundColor = colourForBackground;
    UILabel *label = [[UILabel alloc] initWithFrame:CGRectZero];
    label.backgroundColor = [UIColor clearColor];
    label.font = [UIFont boldSystemFontOfSize:27.0];
    label.textAlignment = NSTextAlignmentCenter;
    label.textColor = [UIColor whiteColor];
    self.navigationItem.titleView = label;
    label.text = @"Notes";
    [label sizeToFit];
    UIColor *colourForButton = [self colorWithHexString:@"919D9F"];
    self.previousButton.backgroundColor = colourForButton;
    self.nextButton.backgroundColor = colourForButton;
    finishedNotes = NO;
    playerPlaying = NO;
    arrayOfImages = [NSArray arrayWithObjects:
                     [UIImage imageNamed:@"1.png"],
                     [UIImage imageNamed:@"2.png"],
                     [UIImage imageNamed:@"3.png"],
                     [UIImage imageNamed:@"4.png"],
                     [UIImage imageNamed:@"5.png"],
                     [UIImage imageNamed:@"6.png"],
                     [UIImage imageNamed:@"7.png"],
                     [UIImage imageNamed:@"8.png"],
                     [UIImage imageNamed:@"9.png"],
                     [UIImage imageNamed:@"10.png"],
                     [UIImage imageNamed:@"11.png"],
                     [UIImage imageNamed:@"12.png"],
                     [UIImage imageNamed:@"13.png"],
                     nil];
}

然后是“下一步”按钮,允许用户继续下一个音符。以下是操作代码

- (IBAction)nextNote:(id)sender {
    if (finishedNotes == YES) {
        [self performSegueWithIdentifier:@"quizFromNotes" sender:self];
    }
    self.previousButton.enabled = YES;
    stateOfPhoto++;
    if (stateOfPhoto < 13) {
        UIImage *image = [arrayOfImages objectAtIndex:stateOfPhoto-1];
        self.imageView.image = image;
    }
    if (stateOfPhoto == 13) {
        UIImage *image = [arrayOfImages objectAtIndex:stateOfPhoto-1];
        self.imageView.image = image;
        [self.nextButton setTitle:@"Begin Quiz" forState:UIControlStateNormal];
        finishedNotes =YES;
    }
    if (playerPlaying == YES) {
        [self.notesPlayer stop];
        playerPlaying = NO;
    }
}

从黑线开始,当我按下“下一步”按钮时,使用的内存增加。它只是重复它自己,直到用户继续进行测试。如果我结束测验,重新开始笔记,内存使用量将继续从以前的内存使用量(73 mb)上升。最终,应用程序会崩溃,我无法再启动应用程序了。

我以前从未遇到过内存泄漏问题,因此我不知道该怎么办。在过去的一个小时里,我一直在用谷歌搜索,但没有找到解决办法。所以我的问题是如何释放内存或减少内存使用。

1 回复 | 直到 9 年前

Glenn Posadas 9 年前

我认为这是因为你的图片,你展示的图片有多大?

https://stackoverflow.com/a/22662754/3231194 ,您可以使用此方法在将图像放入 UIImageView :

-(UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize {
    //UIGraphicsBeginImageContext(newSize);
    // In next line, pass 0.0 to use the current device's pixel scaling factor (and thus account for Retina resolution).
    // Pass 1.0 to force exact pixel size.
    UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
    [image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return newImage;
}

但这将占用CPU使用量(我不确定这是否是一个大问题)。

或