Question

我有一个AVAudioPlayer的子类，在该子类中我有一个停止当前播放器的方法，并且（由于我不解释的原因）手动调用audioPlayerDidFinishPlaying，如下所示：

// Handles stopping the player and calling audioPlayerDidFinishPlaying
- (void) stopPlayerForTimedRepeat {

    // Stop the player
    [self stop];

    // Manually call the audio player callback
    EditPlayListViewController *playlistController = [[EditPlayListViewController alloc] init];
    [playlistController audioPlayerDidFinishPlaying:self successfully:YES];
    [playlistController release];

}

但是，当我像这样手动调用audioPlayerDidFinishPlaying时，原始EditPlaylistViewController中的所有变量都超出了范围。

如何避免这种情况，以便我仍然可以访问所有原始变量？

Answer 1

我想出了一种更好的方法，无需手动调用audioPlayerDidFinishPlaying，以便所有变量仍在范围内。

// Handles stopping the player and calling audioPlayerDidFinishPlaying
- (void) stopPlayerForTimedRepeat {

    // Fast forward the call to the end, which will also call audioPlayerDidFinishPlaying
    [self setCurrentTime:[self duration]];

}

Answer 2

变量作用域丢失是因为您在停止后在方法中创建了一个新对象EditPlayListViewController *playlistController = [[EditPlayListViewController alloc] init];。

请在.h文件中声明播放器（例如此EditPlayListViewController *playlistController;）并使用viewDidLoad方法分配（例如playlistController = [[EditPlayListViewController alloc] init];。

并改变你的方法，

- (void) stopPlayerForTimedRepeat
{
    // Stop the player
     [self stop];

    // Manually call the audio player callback
    [playlistController audioPlayerDidFinishPlaying:self successfully:YES];
    [playlistController release];

}

希望，这对你有用，如果没有，请告诉我。

变量超出范围

2 个答案: