Android编程实现左右滑动切换背景的方法

bgLayout.setOnTouchListener(this);bgLayout.setLongClickable(true);

public boolean onTouch(View v, MotionEvent event) {// TODO Auto-generated method stubreturn this.mGesture.onTouchEvent(event);}

public class SwitcherActivity extends Activity implements OnGestureListener,    OnTouchListener {  /** Called when the activity is first created. */  LinearLayout bgLayout = null;  private GestureDetector mGesture = null;  private int flag = 3;  @Override  public void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);    mGesture = new GestureDetector(this);    bgLayout = (LinearLayout) findViewById(R.id.bg);    bgLayout.setBackgroundResource(R.drawable.bg3);    bgLayout.setOnTouchListener(this);    bgLayout.setLongClickable(true);  }  public boolean onDown(MotionEvent e) {    // TODO Auto-generated method stub    return false;  }  public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,      float velocityY) {    // 处理左右滑动    if (e1.getX() - e2.getX() > 100) { // 向左滑动      if (flag == 3) {        bgLayout.setBackgroundResource(R.drawable.bg4);        flag = 4;        return true;      }      if (flag == 4) {        bgLayout.setBackgroundResource(R.drawable.bg5);        flag = 5;        return true;      }      if (flag == 1) {        bgLayout.setBackgroundResource(R.drawable.bg2);        flag = 2;        return true;      }      if (flag == 2) {        bgLayout.setBackgroundResource(R.drawable.bg3);        flag = 3;        return true;      }    } else if (e1.getX() - e2.getX() < -100) { // 向右滑动      if (flag == 3) {        bgLayout.setBackgroundResource(R.drawable.bg2);        flag = 2;        return true;      }      if (flag == 2) {        bgLayout.setBackgroundResource(R.drawable.bg1);        flag = 1;        return true;      }      if (flag == 5) {        bgLayout.setBackgroundResource(R.drawable.bg4);        flag = 4;        return true;      }      if (flag == 4) {        bgLayout.setBackgroundResource(R.drawable.bg3);        flag = 3;        return true;      }    }    return false;  }  public void onLongPress(MotionEvent e) {    // TODO Auto-generated method stub  }  public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,      float distanceY) {    // TODO Auto-generated method stub    return false;  }  public void onShowPress(MotionEvent e) {    // TODO Auto-generated method stub  }  public boolean onSingleTapUp(MotionEvent e) {    // TODO Auto-generated method stub    return false;  }  public boolean onTouch(View v, MotionEvent event) {    // TODO Auto-generated method stub    return this.mGesture.onTouchEvent(event);  }}