iphone - NSNotification 被调用，但标签不会更新

Question

我使用 NSNotification 中心调用了以下代码，我知道它被调用是因为该数组出现在 NSLog 中，但我的标签 chipCount 未使用新值进行更新。从数组中提取字符串时是否应用了错误的方法？

-(NSString *) dataFilePath {
    NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentDirectory = [path objectAtIndex:0];
    return [documentDirectory stringByAppendingPathComponent:@"Chips.plist"];
}

-(void)readPlist {
    [self dataFilePath];
    NSString *filePath = [self dataFilePath];
    if([[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
        chipArray = [[NSArray alloc] initWithContentsOfFile:filePath];
        NSLog(@"%@\n", chipArray);
        NSLog(@"%@\n", filePath);

        NSString *chipcountString = [chipArray objectAtIndex:0];
        chipsFloat = [chipcountString intValue];
        chipCount.text = [NSString stringWithFormat:@"%i", chipsFloat];
        //[arrayForPlist release];
    }
}

Answer 1

我认为这是一个多线程问题。更新UI必须在主线程中。也许 readPlist 是
在另一个线程中执行。

试试下面的代码，也许它可以帮助你:

[self performSelectorOnMainThread:@selector(theProcess:) withObject:nil waitUntilDone:YES]; 

- (void) theProcess:(id)sender
{

    ....

    chipCount.text = [NSString stringWithFormat:@"%i", chipsFloat];

}