android视频播放简单实现（VideoView&MediaPlayer）

如果你看过我的《android音乐播放简单实现（MediaPlayer）》，那么本篇将会毫无压力。
首先是主界面的三个按钮和一个播放控件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.cofox.myplayvideo.MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <Button
            android:id="@+id/btnPlay"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Play"
            android:textAllCaps="false" />

        <Button
            android:id="@+id/btnPause"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Pause"
            android:textAllCaps="false" />

        <Button
            android:id="@+id/btnReplay"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Replay"
            android:textAllCaps="false" />
    </LinearLayout>
    <VideoView
        android:id="@+id/vdvwFilm"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

在 MainActivity.java 中这里需要用到的是 VideoView 作为视频播放时的显示位置。

 private VideoView videoView;

在 onCreate 里，对界面的按钮和显示位置实例化，并检查权限。

videoView = (VideoView)findViewById(R.id.vdvwFilm);
        Button btnPlay = (Button)findViewById(R.id.btnPlay);
        Button btnPause = (Button)findViewById(R.id.btnPause);
        Button btnReplay = (Button)findViewById(R.id.btnReplay);

        btnPlay.setOnClickListener(this);
        btnPause.setOnClickListener(this);
        btnReplay.setOnClickListener(this);

        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();//初始化MediaPlayer
        }

用一个单独的方法 initVideoPath() 来实现视频播放初始化

    private void initVideoPath() {
        File file = new File(Environment.getExternalStorageDirectory(), "movie2.mp4");
        videoView.setVideoPath(file.getPath());//指定视频文件路径
        videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
            @Override
            public void onPrepared(MediaPlayer mp) {
                mp.setLooping(true);//让电影循环播放
            }
        });
    }

onRequestPermissionsResult 中对权限的取得结果进行判断，并针对性操作。如果获得了权限，就执行初始化；如果没有获得权限，就提示用户。

    @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，无法使用程序。", Toast.LENGTH_LONG).show();
                    finish();
                }
                break;
            default:
                break;
        }
    }

在一个 onClick 方法中，统一处理 Play(播放)、Pause(暂停)、Replay(重新播放)的逻辑。

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.btnPlay:
                if(!videoView.isPlaying()){
                    videoView.start();//播放
                }
                break;
            case R.id.btnPause:
                if(videoView.isPlaying()){
                    videoView.pause();//暂停
                }
                break;
            case R.id.btnReplay:
                if(videoView.isPlaying()){
                    videoView.resume();//重新播放
                }
                break;
        }
    }

执行完毕，释放所有资源。

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

完整代码示例：

package com.cofox.myplayvideo;

import android.Manifest;
import android.content.pm.PackageManager;
import android.media.MediaPlayer;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.os.EnvironmentCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import android.widget.VideoView;

import java.io.File;

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 = (VideoView)findViewById(R.id.vdvwFilm);
        Button btnPlay = (Button)findViewById(R.id.btnPlay);
        Button btnPause = (Button)findViewById(R.id.btnPause);
        Button btnReplay = (Button)findViewById(R.id.btnReplay);

        btnPlay.setOnClickListener(this);
        btnPause.setOnClickListener(this);
        btnReplay.setOnClickListener(this);

        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();//初始化MediaPlayer
        }
    }

    private void initVideoPath() {
        File file = new File(Environment.getExternalStorageDirectory(), "movie2.mp4");
        videoView.setVideoPath(file.getPath());//指定视频文件路径
        videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
            @Override
            public void onPrepared(MediaPlayer mp) {
                mp.setLooping(true);//让电影循环播放
            }
        });
    }

    @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，无法使用程序。", Toast.LENGTH_LONG).show();
                    finish();
                }
                break;
            default:
                break;
        }
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.btnPlay:
                if(!videoView.isPlaying()){
                    videoView.start();//播放
                }
                break;
            case R.id.btnPause:
                if(videoView.isPlaying()){
                    videoView.pause();//暂停
                }
                break;
            case R.id.btnReplay:
                if(videoView.isPlaying()){
                    videoView.resume();//重新播放
                }
                break;
        }
    }

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

在 AndroidManifest.xml 中配置相应的权限。

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.cofox.myplayvideo">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
...

然后我们就可以看到运行结果了。