使用安卓虛擬按鍵控制小飛機的移動小demo

小飛機的View

public class plain extends View{ 
 public float x;            這是定義的飛機的x軸 位置座標
 public float y;  
 Bitmap plain;            新建plain         
 public plain(Context context) {
  super(context);
  plain = BitmapFactory.decodeResource(context.getResources(), R.drawable.ic_launcher);         為plain設定資源 一個飛機的圖片
  setFocusable(true);            設定可成為焦點  可以繫結監聽事件
 }
 
 public void onDraw(Canvas canvas){   畫布     
  super.onDraw(canvas);
  Paint p = new Paint();           新建畫筆
  canvas.drawBitmap(plain, x, y, p);      畫圖
 }
 

}
 

主Activity

public class MainActivity extends ActionBarActivity {

    private int  spend = 10;       設定初始的速度
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.activity_main);
          requestWindowFeature(Window.FEATURE_NO_TITLE);  設定全屏
          final plain plainv = new plain(this);      建立plain類
          setContentView(plainv);         
          //plainv.setBackgroundResource(R.drawable.bk);
          WindowManager windowmangr = getWindowManager();  
          Display display = windowmangr.getDefaultDisplay();
          DisplayMetrics metrics = new DisplayMetrics();         獲取到螢幕寬高
          display.getMetrics(metrics);
          plainv.x = metrics.widthPixels/2;
          plainv.y = metrics.widthPixels-40;
          
          plainv.setOnKeyListener(new OnKeyListener() {        設定鍵盤監聽事件
   
   @Override
   public boolean onKey(View source, int keycode, KeyEvent event) {
           switch (event.getKeyCode()) {
     case KeyEvent.KEYCODE_S:
       plainv.y  += spend;
      break;
     case KeyEvent.KEYCODE_W:
       plainv.y  -= spend;
      break;
     case KeyEvent.KEYCODE_A:
       plainv.x  -= spend;
      break;
     case KeyEvent.KEYCODE_D:
       plainv.x  += spend;
      break;
     default:
      break;
     }
           plainv.invalidate();
    return true;
   }
  });
    }

}