前言

滑動(dòng)后退，很多的app都有的蜻韭，做得好的如微信悼尾，知乎柿扣，簡書等等，這種效果诀豁，我也是挺喜歡的窄刘，網(wǎng)上有開源框架SwipeBackLayout可以實(shí)現(xiàn)，用法可以參考別人的文章：帶你使用SwipeBackLayout和SwipeBackActivity舷胜。

效果

效果圖

簡單實(shí)現(xiàn)

實(shí)現(xiàn)很簡單娩践，不多說，直接看代碼吧

B Activity滑動(dòng)退出時(shí)動(dòng)畫：
anim/push_right_out.xml

<?xml version="1.0" encoding="utf-8"?>
<set
  xmlns:android="http://schemas.android.com/apk/res/android">
    <translate android:interpolator="@android:anim/decelerate_interpolator" android:duration="400" android:fromXDelta="0.0" android:toXDelta="100.0%p" />
</set>

A Activity在B Activity退出時(shí)A Activity進(jìn)入的動(dòng)畫
anim/zoom_out.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <scale
        android:duration="400"
        android:fillBefore="false"
        android:fromXScale="0.9"
        android:fromYScale="0.9"
        android:interpolator="@android:anim/decelerate_interpolator"
        android:pivotX="50.0%"
        android:pivotY="50.0%"
        android:toXScale="1.0"
        android:toYScale="1.0" />
    <alpha
        android:duration="400"
        android:fromAlpha="0.1"
        android:interpolator="@android:anim/decelerate_interpolator"
        android:toAlpha="1.0" />
</set>

這里實(shí)現(xiàn)了GestureDetector對(duì)滑動(dòng)進(jìn)行監(jiān)聽

private void initDetector() {
        if (!isSwipeBack)
            return;
        mDetector = new GestureDetector(this, new GestureDetector.SimpleOnGestureListener() {
            public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
                float f2 = e1.getX() - e2.getX();
                float f1 = f2 / (e1.getY() - e2.getY());
                if ((f1 > 3.0F) || (f1 < -3.0F)) {//右滑后退
                    if (f2 <= -160.0F) {
                        finish();
                        overridePendingTransition(R.anim.zoom_out, R.anim.push_right_out); //注意烹骨，需要在finish后翻伺，否則不起作用
                        return true;
                    }

                }
                return false;
            }
        });
    }
    private boolean isSwipeBack = true;
    public void setSwipeBack(boolean swipeBack) { //設(shè)置是否需要啟用右滑后退，默認(rèn)啟用
        isSwipeBack = swipeBack;
    }

    public boolean dispatchTouchEvent(MotionEvent event) {
        if (isSwipeBack && (mDetector != null) && (event != null)) {
            if (mDetector.onTouchEvent(event)) return true;//如果處理了就直接return回去
        }
        return super.dispatchTouchEvent(event);
    }