Android闹钟音量逐渐增加

Question

我有一个闹钟类，可以按时播放默认的闹钟铃声。我想在一段时间内播放闹钟铃声，音量从最小到最大。我怎样才能从最小值到最大值逐渐增加音量。样本代码或项目是否有链接？请帮我

Answer 1

你可以自己做。没有什么复杂的。

一旦你的PendingIntent被触发，请利用处理程序来增加。

1. 创建类，将采取AudioManager或应用作为参数的Context。

   public class VolumeRunnable implements Runnable{ 
   
   private AudioManager mAudioManager; 
   private Handler mHandlerThatWillIncreaseVolume; 
   private final static int DELAY_UNTILL_NEXT_INCREASE = 30*1000;//30 seconds between each increment 
   VolumeRunnable(AudioManager audioManager, Handler handler){ 
       this.mAudioManager = audioManager; 
       this.mHandlerThatWillIncreaseVolume = handler; 
   } 
   
   @Override 
   public void run(){ 
       int currentAlarmVolume = mAudioManager.getStreamVolume(AudioManager.STREAM_ALARM); 
       if(currentAlarmVolume != mAudioManager.getStreamMaxVolume(AudioManager.STREAM_ALARM)){ //if we havent reached the max 
   
       //here increase the volume of the alarm stream by adding currentAlarmVolume+someNewFactor 
        mHandlerThatWillIncreaseVolume.postDelayed(this,DELAY_UNTILL_NEXT_INCREASE); //"recursively call this runnable again with some delay between each increment of the volume, untill the condition above is satisfied. 
       } 
   
   } 
   

   }

2. 调用此Runnable一旦PendingIntent被触发：

someHandler.post（新VolumeRunnable（mAudioManager，someHandler））;

我希望这给你的想法。原谅任何错误或错别字。