在Android中沒有觸摸感應的檢測按鈕

Question

我有8個按鈕我希望應用通過在屏幕上滾動而不是通過觸摸來檢測按鈕？像果凍豆的可訪問性功能？我不知道如何將該功能稱爲？手勢？動感？

這可能嗎？我應該尋找什麼？

謝謝！

Answer 1

默認情況下，Android中的UI元素可以通過滾動球，箭頭鍵等進行關注...視圖具有View.setOnFocusChangedListener回調。您也可以以編程方式設置元素的焦點。

我很快編寫了一些示例代碼，沒有測試。

float initialX = 0; 
float initialY = 0; 
int currentFocusedChild = 0; 
List<View> children; 

public void walkElements() { 
    final LinearLayout mainLayout = (LinearLayout) findViewById(R.id.main_layout); 
    children = mainLayout.getFocusables(View.FOCUS_FORWARD); 
    mainLayout.setOnTouchListener(new OnTouchListener() { 

     @Override 
     public boolean onTouch(View v, MotionEvent event) { 
      switch(event.getAction()) { 
       case MotionEvent.ACTION_DOWN: 
        initialX = event.getX(); 
        initialY = event.getY();       
        break; 
       case MotionEvent.ACTION_MOVE: 
        float diffX = event.getX() - initialX; 
        float diffY = event.getY() - initialY; 

        if(diffY > 0) { 
         if (currentFocusedChild < children.size() - 1) { 
          currentFocusedChild++; 
         } 
        } else { 
         if (currentFocusedChild > 0) { 
          currentFocusedChild--; 
         } 
        } 
        children.get(currentFocusedChild).setSelected(true); 

        //Sleep for a period of time so the selection is slow enough for the user. 
        Thread.sleep(300); 
        break; 
       case MotionEvent.ACTION_UP: 
        children.get(currentFocusedChild).performClick(); 
        break; 
      } 
      return false; 
     } 
    }); 

}