第一行代码（第2版）：菜鸡踩坑系列----8.4多媒体视频播放

第一行代码 8.4 播放多媒体（已解决）

问题可能不一样！！！

8.4.1

已确认代码无误，权限已加，手机根目录已放置相应同名文件。
使用真机运行的代码（手机型号：redmi K20）模拟器也尝试不成功，点击按钮后无效。
报错如下：
(并提示无法播放视屏)

W/VideoView: Unable to open content: /storage/emulated/0/movie.mp4
    java.io.FileNotFoundException: /storage/emulated/0/movie.mp4: 
    open failed: EACCES (Permission denied)

具体原因不清楚，但是可以正常播放了

下面附上我的代码：
1.布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/play"
            android:text="播放"/>
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/pause"
            android:text="暂停"/>

        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/replay"
            android:text="重播"/>

    LinearLayout>
    <VideoView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/video_view"/>

LinearLayout>

2.MainActivity

package com.example.playvideotest;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import android.widget.VideoView;

import java.io.File;
import java.util.function.ToIntBiFunction;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private VideoView videoView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        videoView=findViewById(R.id.video_view);
        Button play=findViewById(R.id.play);
        Button pause=findViewById(R.id.pause);
        Button replay=findViewById(R.id.replay);
        play.setOnClickListener(this);
        pause.setOnClickListener(this);
        replay.setOnClickListener(this);

        if (Build.VERSION.SDK_INT >= 23) {
            int REQUEST_CODE_CONTACT = 101;
            String[] permissions = {Manifest.permission.WRITE_EXTERNAL_STORAGE};//验证是否许可权限
            for (String str : permissions) {
                if (this.checkSelfPermission(str) != PackageManager.PERMISSION_GRANTED)
                { //申请权限
                    this.requestPermissions(permissions, REQUEST_CODE_CONTACT);
                    return;
                }
            }
        }
        if(ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
        != PackageManager.PERMISSION_GRANTED){
            ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
        }else
        {
            initVideoPath();
        }
    }
    private void initVideoPath(){
        try {
            File file=new File(Environment.getExternalStorageDirectory(),"/movie.mp4");
            //File file=Context(getExternalFilesDir(String));
            videoView.setVideoPath(file.getPath());
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode){
            case 1:
                if(grantResults.length>0&& grantResults[0]==PackageManager.PERMISSION_GRANTED){
                    initVideoPath();
                }else{
                    Toast.makeText(this,"拒绝权限将无法使用程序", Toast.LENGTH_SHORT).show();
                    finish();
                }
        }
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.play:
                if(!videoView.isPlaying()){
                    videoView.start();
                }
                break;
            case R.id.pause:
                if(videoView.isPlaying()){
                    videoView.pause();
                }
                break;
            case R.id.replay:
                if(videoView.isPlaying()){
                    videoView.resume();
                }
                break;
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if(videoView!=null){
            videoView.suspend();
        }
    }
}

3.AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.playvideotest">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"
        tools:ignore="ProtectedPermissions" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:requestLegacyExternalStorage="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            intent-filter>
        activity>
    application>

manifest>