android開發步步為營之72:右滑關閉Activity

通過右滑手勢關閉當前Activity，這個是很常見的需求，網上參考過幾篇文章發現實現都比較復雜，他們大多自己另外寫了個Layout，然後這個Layout當做頁面的布局，經測試其實有更簡單一點的方法，寫個BaseActivity，其他Activity繼承即可。這裡給出代碼，大家測試看看。有問題回饋一下，謝謝！

package com.figo.study.activity;

import android.app.Activity;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;

public class BaseActivity extends Activity implements View.OnTouchListener, GestureDetector.OnGestureListener {
    GestureDetector mGestureDetector;

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return mGestureDetector.onTouchEvent(event);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mGestureDetector = new GestureDetector((GestureDetector.OnGestureListener) this);
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        mGestureDetector.onTouchEvent(ev);
        return super.dispatchTouchEvent(ev);
    }

    @Override
    public boolean onDown(MotionEvent e) {
        return false;
    }

    @Override
    public void onShowPress(MotionEvent e) {

    }

    @Override
    public boolean onSingleTapUp(MotionEvent e) {
        return false;
    }

    @Override
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
        return false;
    }

    @Override
    public void onLongPress(MotionEvent e) {

    }

    private int verticalMinDistance = 20;
    private int minVelocity = 0;

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
        if (Math.abs(e2.getY() - e1.getY()) > 200) {//這裡是避免有scroolview的頁面上劃也關閉
            return false;
        }
        if (e1.getX() - e2.getX() > verticalMinDistance && Math.abs(velocityX) > minVelocity) {//左滑操作
        } else if (e2.getX() - e1.getX() > verticalMinDistance && Math.abs(velocityX) > minVelocity) {//右滑操作
            this.finish();
        }

        return false;
    }
}