/**  * 隱藏虛擬按鍵，并且設置成全屏  */  protected void hideBottomUIMenu(){   if (Build.VERSION.SDK_INT > 11 && Build.VERSION.SDK_INT < 19) { // lower api    View v = this.getWindow().getDecorView();    v.setSystemUiVisibility(View.GONE);   } else if (Build.VERSION.SDK_INT >= 19) {    //for new api versions.    View decorView = getWindow().getDecorView();    int uiOptions = View.SYSTEM_UI_FLAG_LAYOUT_STABLE      | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION      | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN      | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION // hide nav bar       | View.SYSTEM_UI_FLAG_FULLSCREEN // hide status bar      | View.SYSTEM_UI_FLAG_IMMERSIVE;    decorView.setSystemUiVisibility(uiOptions);    getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);   } } 

/**  * 檢查是否存在虛擬按鍵欄  * @param context  * @return  */   public static boolean hasNavBar(Context context) {    Resources res = context.getResources();  //這種方式一定要注意寫法要正確，內部應該是通過反射去調用的。   int resourceId = res.getIdentifier("config_showNavigationBar", "bool", "android");    if (resourceId != 0) {     boolean hasNav = res.getBoolean(resourceId);     // check override flag     String sNavBarOverride = getNavBarOverride();     if ("1".equals(sNavBarOverride)) {      hasNav = false;     } else if ("0".equals(sNavBarOverride)) {      hasNav = true;     }     return hasNav;    } else { // fallback     return !ViewConfiguration.get(context).hasPermanentMenuKey();    }   }   /**    * 判斷虛擬按鍵欄是否重寫    * @return    */   private static String getNavBarOverride() {    String sNavBarOverride = null;    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {     try {      Class c = Class.forName("android.os.SystemProperties");      Method m = c.getDeclaredMethod("get", String.class);      m.setAccessible(true);      sNavBarOverride = (String) m.invoke(null, "qemu.hw.mainkeys");     } catch (Throwable e) {    }   }   return sNavBarOverride; }