Android鬧鐘音量逐漸增加

Question

我有一個鬧鐘類，可以按時播放默認的鬧鐘鈴聲。我想在一段時間內播放鬧鐘鈴聲，音量從最小到最大。我怎樣才能從最小值到最大值逐漸增加音量。樣本代碼或項目是否有鏈接？請幫我

Answer 1

你可以自己做。沒有什麼複雜的。

一旦你的PendingIntent被觸發，請利用處理程序來增加。

1. 創建類，將採取AudioManager或應用作爲參數的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. 調用此Runnable一旦PendingIntent被觸發：

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

我希望這給你的想法。原諒任何錯誤或錯別字。