我非常简单的 iPhone 应用程序 10 次中有 6 次在启动时显示损坏或随机崩溃。但它在模拟器中表现良好。显示损坏看起来像字体颜色错误、字体文本不合适、背景颜色错误等。
我发现了一个奇怪的解决方法..当我的线程在调用“完成”通知之前延迟 2 秒时,一切正常。线程读取网页,“完成”通知加载带有字符串的 PickerView。那么给了什么?我不能从 viewDidLoad 安全地启动线程任务吗?
- (void) loadWebPage:(NSString *)urlAddition {
NSAutoreleasePool *subPool = [[NSAutoreleasePool alloc] init];
NSString *pageSource;
NSError *err;
NSString *urlString = [NSString stringWithFormat:@"http://server/%@",
urlAddition];
pageSource = [NSString stringWithContentsOfURL:[NSURL URLWithString: urlString]
encoding:NSUTF8StringEncoding
error:&err];
[NSThread sleepForTimeInterval:2.0]; // THIS STOPS THE DISPLAY CORRUPTION
[[NSNotificationCenter defaultCenter] postNotificationName:@"webDoneNotification"
object:nil];
[subPool drain];
}
- (void) webDoneNotification: (NSNotification *)pNotification {
[mediaArray release];
mediaArray = [[NSArray arrayWithObjects:
[NSString stringWithString:@"new pickerview text"],
nil] retain];
[mediaPickerView reloadAllComponents];
[mediaPickerView selectRow:0
inComponent:0
animated:NO];
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
mediaArray = [[NSArray arrayWithObjects:
[NSString stringWithString:@"init pickerview text"],
nil] retain];
if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad {
[super viewDidLoad];
myWebThread = [[WebThread alloc] initWithDelegate:self];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(webDoneNotification:)
name:@"webDoneNotification"
object:nil];
[myWebThread performSelectorInBackground:@selector(loadWebPage:) withObject:@""];
}
谢谢!
更新:即使是 0.1 秒的延迟也足以彻底解决问题。