Android連續點擊兩次Back鍵退出程式

標籤：android   private   public   method   程式   

     思路1：記錄上次點擊的時間，與本次點擊的時間比較，當兩次時間間隔小於一定值時，退出，否則提示“再按一次退出程式”，同時更新上次點擊時間

     private long firstTime = 0;     @Override  public boolean onKeyUp(int keyCode, KeyEvent event) {         // TODO Auto-generated method stub         switch(keyCode)         {         case KeyEvent.KEYCODE_BACK:              long secondTime = System.currentTimeMillis();                if (secondTime - firstTime > 2000) {                                         //如果兩次按鍵時間間隔大於2秒，則不退出                   Toast.makeText(this, "再按一次退出程式", Toast.LENGTH_SHORT).show();                    firstTime = secondTime;//更新firstTime                   return true;                } else {                                                    //兩次按鍵小於2秒時，退出應用              System.exit(0);               }              break;         }       return super.onKeyUp(keyCode, event);     }

思路2：開線程延時處理

private int mBackKeyPressedTimes = 0;            @Override          public void onBackPressed() {                  if (mBackKeyPressedTimes == 0) {                          Toast.makeText(this, "再按一次退出程式 ", Toast.LENGTH_SHORT).show();                          mBackKeyPressedTimes = 1;                          new Thread() {                                  @Override                                  public void run() {                                          try {                                                  Thread.sleep(2000);                                          } catch (InterruptedException e) {                                                  e.printStackTrace();                                          } finally {                                                  mBackKeyPressedTimes = 0;                                          }                                  }                          }.start();                          return;                        else{                                 this.activity.finish();                              }                  }                  super.onBackPressed();          }

1. 
   

Android連續點擊兩次Back鍵退出程式