移动开发：图像查看器

一、新建ImageViewer模块，添加p1-p9图片(注意mdpi后缀)

二、相关代码

1.MainActivity.java文件代码

package com.example.imageviewer;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
import android.view.animation.AnimationUtils;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.ViewSwitcher;

public class MainActivity extends AppCompatActivity {
    private int[] arrayPicture = new int[]{R.drawable.p1,R.drawable.p2,R.drawable.p3,R.drawable.p4,
            R.drawable.p5,R.drawable.p6,R.drawable.p7,R.drawable.p8,R.drawable.p9};
    private ImageSwitcher imageSwitcher;
    private int index;
    private float touchDownX;
    private float touchUpX;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN); //设置全屏显示
        imageSwitcher = (ImageSwitcher) findViewById(R.id.imageswitcher);
        imageSwitcher.setFactory(new ViewSwitcher.ViewFactory() {
            @Override
            public View makeView() {
                ImageView imageView = new ImageView(MainActivity.this);
                imageView.setImageResource(arrayPicture[index]);
                return imageView;
            }

        });
        imageSwitcher.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                if(event.getAction() == MotionEvent.ACTION_DOWN){
                    touchDownX = event.getX();
                    return true;
                }else if(event.getAction() == MotionEvent.ACTION_UP){
                    touchUpX = event.getX();
                    if(touchUpX-touchDownX>100){
                        index = index == 0?arrayPicture.length-1:index-1;
                        imageSwitcher.setInAnimation(AnimationUtils.loadAnimation(MainActivity.this,R.anim.slide_in_left));
                        imageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(MainActivity.this,R.anim.slide_out_right));
                        imageSwitcher.setImageResource(arrayPicture[index]);

                        
                    }else if (touchDownX-touchUpX>100){
                        index = index == arrayPicture.length-1?0:index+1;
                        imageSwitcher.setInAnimation(AnimationUtils.loadAnimation(MainActivity.this,R.anim.slide_in_right));
                        imageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(MainActivity.this,R.anim.slide_out_left));
                        imageSwitcher.setImageResource(arrayPicture[index]);

                    }
                    return true;
                }
                return false;
            }
        });
    }
}

2.activity_main.xml文件代码

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <ImageSwitcher
        android:id="@+id/imageswitcher"
        android:layout_centerVertical="true"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">

    </ImageSwitcher>


</RelativeLayout>