這是一個播放本地視訊的播放器，videoUrl1是手機裡放置視訊的路徑

效果圖：

MainActivity.java

package com.example.aimee.videotest;

import android.Manifest;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
 
import android.os.Bundle;
import android.view.WindowManager;
import android.widget.MediaController;
import android.widget.Toast;
import android.widget.VideoView;

public class MainActivity extends AppCompatActivity {
    private final int REQUESTCODE=101;
    private VideoView videoView;

    @Override
    
 
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout);

        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        if(Build.VERSION.SDK_INT>= Build.VERSION_CODES.M){
            
 
int checkSelfPermission=checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE);
            if(checkSelfPermission== PackageManager.PERMISSION_DENIED){
                requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},REQUESTCODE);
            }
        }
        play_mp4();

    }

    private void play_mp4(){
        String videoUrl1 = "/storage/emulated/0/save/a1.mp4";
        Uri uri = Uri.parse( videoUrl1 );
        videoView = (VideoView)this.findViewById(R.id.videoView );
        videoView.setMediaController(new MediaController(this));
        videoView.setVideoURI(uri);
        videoView.start();
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults){
        super.onRequestPermissionsResult(requestCode,permissions,grantResults);
        if(requestCode==REQUESTCODE){
            if (permissions[0].equals(Manifest.permission.WRITE_EXTERNAL_STORAGE) && grantResults[0]== PackageManager.PERMISSION_GRANTED){
                Toast.makeText(this,"ok", Toast.LENGTH_LONG).show();

            }else {
                Toast.makeText(this,"無許可權",Toast.LENGTH_LONG).show();
            }
        }
    }
}

layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

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

androidmanifest.xml中要新增許可權

    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.INTERNET" />

注意：使用模擬器播放時，要確保路徑下有那個視訊。從電腦傳視訊到模擬器的方法在上一篇中有。不過，每次傳完當時可以用，不過重啟電腦或重啟模擬器時，那個視訊檔案會丟失，所以下次想用時得重新上傳。我是用的ADV tools裡面建立的模擬器，不知道其他模擬器會不會同樣如此。