Android ImageView 实现图片触屏左右、上下以及按钮切换图片

布局代码：

<?xml version="1.0" encoding="utf-8"?>
<!--suppress ALL -->
<LinearLayout xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:gravity="center"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">

<!--        <ImageView android:id="@+id/image"
            android:layout_width="355dip"
            android:layout_height="650dip"
            android:src="@drawable/p2"/>-->
        <ImageSwitcher
            android:layout_width="355dp"
            android:layout_height="650dp"
            android:id="@+id/image"
            />
    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="fill_parent">
        <Button android:id="@+id/up"
            android:layout_width="150dip"
            android:layout_height="wrap_content"
            android:text="上一张"/>
        <Button android:id="@+id/down"
            android:layout_width="150dip"
            android:layout_height="wrap_content"
            android:text="下一张"/>
    </LinearLayout>
</LinearLayout>

JAVA代码：

package com.android.booktest;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.ViewSwitcher;

public class MainActivity extends AppCompatActivity {
    Button Button1,Button2;
    int[] images={
            R.drawable.p1, R.drawable.p2,R.drawable.p3
    };
//    ImageView image;
    ImageSwitcher image;
    private float x;
    private float y;
    private float dx;
    private float dy;
    int index=0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button1 = (Button)findViewById(R.id.up);
        Button2 = (Button)findViewById(R.id.down);
        image = (ImageSwitcher) findViewById(R.id.image);
        // 必须设置
        image.setFactory(new ViewSwitcher.ViewFactory() {
            @Override
            public View makeView() {
                ImageView imageView=new ImageView(MainActivity.this);
                imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
                return imageView;
            }
        });
        image.setInAnimation(AnimationUtils.loadAnimation(this,android.R.anim.fade_in));
        image.setOutAnimation(AnimationUtils.loadAnimation(this,android.R.anim.fade_out));
        image.setImageResource(images[0]);
        Button1.setOnClickListener(new mclik());
        Button2.setOnClickListener(new mclik());
        image.setOnTouchListener(new touchme());
    }

    class mclik implements View.OnClickListener{

        @Override
        public void onClick(View v) {
            if(v==Button1){
                backpic();
            }
            if(v==Button2){
                nextpic();
            }
        }
    }

    private void backpic(){
        if(index>0&&index<images.length){
            index--;
            image.setImageResource(images[index]);
        }else {
            index=images.length-1;
            image.setImageResource(images[index]);
        }
    }

    private void nextpic(){
        if(index>=0&&index<images.length-1){
            index++;
            image.setImageResource(images[index]);
        }else {
            index=0;
            image.setImageResource(images[index]);
        }
    }

    //左右滑动
/*
    private class touchme implements View.OnTouchListener {

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if(event.getAction()==MotionEvent.ACTION_DOWN){
                x = event.getX();
                y = event.getY();
            } else if (event.getAction() == MotionEvent.ACTION_UP)  {
                dx = event.getX() - x;
                dy = event.getY() - y;
                if (dx > 0 && Math.abs(dy)<50 && Math.abs(dy)>0) {
                    nextpic();
                } else if (dx < 0 && Math.abs(dy)<50 && Math.abs(dy)>0) {
                    backpic();
                }
            }
            return true;
        }
    }
*/

    //上下滑动
    private class touchme implements View.OnTouchListener {

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if(event.getAction()==MotionEvent.ACTION_DOWN){
                x = event.getX();
                y = event.getY();
            } else if (event.getAction() == MotionEvent.ACTION_UP)  {
                dx = event.getX() - x;
                dy = event.getY() - y;
                if (dy > 0 && Math.abs(dx)<50 && Math.abs(dx)>0) {
                    nextpic();
                } else if (dy < 0 && Math.abs(dx)<50 && Math.abs(dx)>0) {
                    backpic();
                }
            }
            return true;
        }
    }
}