Question

我遇到了UIImageView动画的一些问题。我创建了三个包含图像的NSArray对象，并创建了三个采用UIImageView并为其分配新动画的方法。它第一次调用三种方法中的一种非常有效，但是另一次它会使模拟器和设备崩溃。任何想法？

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {

// set the anims
slowAnimation = [NSArray arrayWithObjects:
                    [UIImage imageNamed:@"image1.jpg"],
                    [UIImage imageNamed:@"image2.jpg"],
                                nil];
defaultAnimation = [NSArray arrayWithObjects:
                    [UIImage imageNamed:@"image3.jpg"],
                    [UIImage imageNamed:@"image4.jpg"],
                        nil];
fastAnimation = [NSArray arrayWithObjects:
                    [UIImage imageNamed:@"image5.jpg"],
                    [UIImage imageNamed:@"image6.jpg"],
                    nil];

// load the default speed - this works once, but when applied a second time it crashes the simulator and device
[self setDefaultAnim:myUIImageViewObject];

[super viewDidLoad];
}


// animation switcher
-(void)setSlowAnim:(UIImageView *)imageView
{
    [imageView stopAnimating];
    imageView.animationImages = slowAnimation;
    imageView.animationDuration = 0.4;
    [imageView startAnimating];
}
-(void)setDefaultAnim:(UIImageView *)imageView
{
    [imageView stopAnimating];
    imageView.animationImages = defaultAnimation;
    imageView.animationDuration = 0.4;
        [imageView startAnimating];
}
-(void)setFastAnim:(UIImageView *)imageView
{
    [imageView stopAnimating];
    imageView.animationImages = fastAnimation;
    imageView.animationDuration = 0.4;
   [imageView startAnimating];
}

日志错误：

[Session started at 2009-04-06 22:46:54 +0100.]
Loading program into debugger…
GNU gdb 6.3.50-20050815 (Apple version gdb-962) (Sat Jul 26 08:14:40 UTC 2008)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i386-apple-darwin".warning: Unable to read symbols for "/System/Library/Frameworks/UIKit.framework/UIKit" (file not found).
warning: Unable to read symbols from "UIKit" (not yet mapped into memory).
warning: Unable to read symbols for "/System/Library/Frameworks/CoreGraphics.framework/CoreGraphics" (file not found).
warning: Unable to read symbols from "CoreGraphics" (not yet mapped into memory).
Program loaded.
sharedlibrary apply-load-rules all
Attaching to program: `/Users/hello/Library/Application Support/iPhone Simulator/User/Applications/6DB7C45D-1A26-4775-9AE3-C30F3EBC9F83/PlateSpinner.app/PlateSpinner', process 345.
kill
quit

The Debugger has exited with status 0.

Answer 1

我认为你需要retain在viewDidLoad中创建的三个数组 - 你永远不会在它们上面调用alloc，所以在你致电{{1}之前你没有所有权}}

Answer 2

而不是仅调用retain使用initWithObjects消息：

slowAnimation = [[NSArray alloc] initWithObjects:
                                  [UIImage imageNamed:@"image1.jpg"],
                                  [UIImage imageNamed:@"image2.jpg"],
                                  nil];

Answer 3

如果您按照Lounges的建议行事，请注意您稍后需要释放slowAnimation对象。由于你分配了它，它的保留计数为1，直到有人告诉运行时。

iPhone UIImageView动画难题

3 个答案: