android实现左滑关闭activity和返回上一个activity

public void registerActivityLifecycleCallbacks(ActivityLifecycleCallbacks callback) {}

    private static final int MSG_ACTION_DOWN = 1; //点击事件  
    private static final int MSG_ACTION_MOVE = 2; //滑动事件
    private static final int MSG_ACTION_UP = 3;  //点击结束
    private static final int MSG_SLIDE_CANCEL = 4; //开始滑动，不返回前一个页面
    private static final int MSG_SLIDE_CANCELED = 5;  //结束滑动，不返回前一个页面
    private static final int MSG_SLIDE_PROCEED = 6; //开始滑动，返回前一个页面
    private static final int MSG_SLIDE_FINISHED = 7;//结束滑动，返回前一个页面

   public class BaseActivity extends AppCompatActivity {
    private static final String TAG = "BaseActivity";
    private SwipeWindowHelper mSwipeWindowHelper;
    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        if(!supportSlideBack()) {
            return super.dispatchTouchEvent(ev);
        }
        if(mSwipeWindowHelper == null) {
            mSwipeWindowHelper = new SwipeWindowHelper(getWindow());
        }
        return mSwipeWindowHelper.processTouchEvent(ev) || super.dispatchTouchEvent(ev);
    }
    /**
     * 是否支持滑动返回
     *
     * @return
     */
    protected boolean supportSlideBack() {
        return true;
    }
   }