滑动方向的判断（2种类的使用）

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:id="@+id/layout">
</LinearLayout>

package hello.world.button;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;

public class MainActivity extends AppCompatActivity {
    private GestureDetector mGestureDetector;//手势处理

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.mGestureDetector = new GestureDetector(this, new MyGestureListener());
        View view = findViewById(R.id.layout);
        view.setFocusable(true);
        view.setFocusableInTouchMode(true);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        return mGestureDetector.onTouchEvent(event);
    }

    private class MyGestureListener extends GestureDetector.SimpleOnGestureListener {

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            /*
             *  滑动 使用 onFling（）方法
             *  3.判断
             */
            String result = drawTouch(e1.getX(), e1.getY(), e2.getX(), e2.getY());
            Log.d("onFling ", ": " + result);
            return true;
        }
    }

    /**
     * 手势判断
     *
     * @param x
     * @param y
     * @param upx
     * @param upy
     * @return
     */
    private String drawTouch(float x, float y, float upx, float upy) {

        String str = "没有滑动";
        //水平滑动
        if (upx - x > 100) {
            str = "向右滑动";
        } else if (x - upx > 100) {
            str = "向左滑动";
        } else if (upy - y > 100) {
            str = "向下滑动";
        } else if (y - upy > 100) {
            str = "向上滑动";
        }
        return str;
    }
}

package hello.world.button;

import android.content.Context;
import android.content.res.Configuration;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.TypedValue;
import android.view.Display;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnTouchListener{
    private GestureDetector mGestureDetector;//手势处理

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.mGestureDetector = new GestureDetector(this,new GestureDetector.OnGestureListener() {
            @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) {
//                float minMove = 120; // 最小滑动距离
//                float minVelocity = 0; // 最小滑动速度
//                float beginX = e1.getX();
//                float endX = e2.getX();
//                float beginY = e1.getY();
//                float endY = e2.getY();
//
//                if (beginX - endX > minMove && Math.abs(distanceX) > minVelocity) { // 左滑
//                    Log.d("方向", "onFling: 左");
//                } else if (endX - beginX > minMove && Math.abs(distanceX) > minVelocity) { // 右滑
//                    Log.d("方向", "onFling: 右");
//                } else if (beginY - endY > minMove && Math.abs(distanceY) > minVelocity) { // 上滑
//                    Log.d("方向", "onFling: 上");
//                } else if (endY - beginY > minMove && Math.abs(distanceY) > minVelocity) { // 下滑
//                    Log.d("方向", "onFling: 下");
//                }
                return false;
            }

            @Override
            public void onLongPress(MotionEvent e) {

            }

            @Override
            public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
                float minMove = 120; // 最小滑动距离
                float minVelocity = 0; // 最小滑动速度
                float beginX = e1.getX();
                float endX = e2.getX();
                float beginY = e1.getY();
                float endY = e2.getY();

                if (beginX - endX > minMove && Math.abs(velocityX) > minVelocity) { // 左滑
                    Log.d("方向", "onFling: 左");
                } else if (endX - beginX > minMove && Math.abs(velocityX) > minVelocity) { // 右滑
                    Log.d("方向", "onFling: 右");
                } else if (beginY - endY > minMove && Math.abs(velocityY) > minVelocity) { // 上滑
                    Log.d("方向", "onFling: 上");
                } else if (endY - beginY > minMove && Math.abs(velocityY) > minVelocity) { // 下滑
                    Log.d("方向", "onFling: 下");
                }
                return false;
            }
        });
        View view =findViewById(R.id.layout);
        view.setFocusable(true);
        view.setOnTouchListener(this);
        view.setLongClickable(true);
        view.setLongClickable(true);
    }


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

onFling，onScroll的区别是
onScroll是触摸时候一直数据的
onFling是触摸停止后才有数据的