ios - 如何使用 NSUserDefaults 保存和检索数据

Question

我的应用中有 100 个视频的数据。我需要暂停或停止时的每个视频播放时间我需要使用 NSUserDefaults 存储所有视频播放时间。我怎样才能做到这一点？

我试过了。它可以很好地显示停止的持续时间，但我需要在单个键值引用(如数组或字典)中保存停止、暂停和完整的视频持续时间。

-(void) moviePlayerPlaybackStateDidChange:(NSNotification*)notification {

    NSLog(@"playbackDidChanged");
    moviePlayer = notification.object;
    MPMoviePlaybackState playbackState = moviePlayer.playbackState;
    if(playbackState == MPMoviePlaybackStateStopped) {
        NSLog(@"MPMoviePlaybackStateStopped at %f while the full length is %f", moviePlayer.currentPlaybackTime, moviePlayer.duration);
        NSLog(@"video title %@",videoTitle);
        [[NSUserDefaults standardUserDefaults] setDouble:moviePlayer.currentPlaybackTime forKey:videoTitle];
        [[NSUserDefaults standardUserDefaults] synchronize];
        NSLog(@"User default value : %@", [[NSUserDefaults standardUserDefaults] objectForKey:videoTitle]); 
    } else if(playbackState == MPMoviePlaybackStatePlaying) {
        NSLog(@"MPMoviePlaybackStatePlaying");
    } else if(playbackState == MPMoviePlaybackStatePaused) {
        NSLog(@"MPMoviePlaybackStatePaused : %f",moviePlayer.currentPlaybackTime);
        [[NSUserDefaults standardUserDefaults]setDouble:moviePlayer.currentPlaybackTime forKey:videoTitle];
    } 
}

Answer 1

其实，当我想到这个的时候。如果您知道每个视频的位置，并且准备将这些值添加到 NSUserDefaults，我会将所有内容存储在字典数组中。然后您只有一个默认项而不是 100 个。而且应该很容易找出您需要哪一个。