两个类实现Android录制屏幕功能

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两个类实现Android录制屏幕功能

随着5G的到来，屏幕共享、音视频成为火热的话题，音视频对于普通开发者来说还是算比较复杂，这篇文章主要讲解在Android中如何进行屏幕录制。

一、原理

在Android5.0之前，需要获取Root权限才能支持屏幕共享。 在Android5.0之后，Android API 开放了视频录制的接口，MediaProjection 和 MediaProjectionManager 在 API 21上增加。 该篇文章是基于该方法进行的录制。

在Windows平台，我们可以使用RDP进行屏幕共享。 在Android 平台，没有官方的屏幕共享技术，所以只能通过录屏之后进行编码传输，接收方进行解码并显示。

二、操作步骤

2.1 申请权限

先申请存储权限

  1. AndroidManifest配置
    <uses-permission android:name="android.permission.RECORD_AUDIO" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
  1. Android6.0后的动态权限
public static void checkPermission(AppCompatActivity activity) {
        if (Build.VERSION.SDK_INT >= 23) {
            int checkPermission =
                    ContextCompat.checkSelfPermission(activity, Manifest.permission.RECORD_AUDIO)
                            + ContextCompat.checkSelfPermission(activity, Manifest.permission.READ_PHONE_STATE)
                            + ContextCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                            + ContextCompat.checkSelfPermission(activity, Manifest.permission.READ_EXTERNAL_STORAGE);
            if (checkPermission != PackageManager.PERMISSION_GRANTED) {
                //动态申请
                ActivityCompat.requestPermissions(activity, new String[]{
                        Manifest.permission.RECORD_AUDIO,
                        Manifest.permission.READ_PHONE_STATE,
                        Manifest.permission.READ_EXTERNAL_STORAGE,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE}, 123);
            }
        }
    }

2.2 允许录制屏幕

分析一下流程

  1. 检查权限
checkPermission(this);
  1. 初始化获取MediaProjectionManager

 通过调用getSystemService方法获取MediaProjectionManager的实例

mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE);
  1. 申请录制屏幕

由于安卓权限的收紧，高级别的权限都需要显式的提醒用户，用户给到权限之后才可以进行屏幕的录制。因为录屏产生的危险系数很高，可以看到屏幕上的所有内容，所以会显式的提醒用户

  1. 在onActivityResult拿到权限是否允许的结果

在onActivityResult 中获取requestCode == REQUEST_CODE 和 resultCode == Activity.RESULT_OK 同时满足时，即用户允许了权限。

 @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_CODE && resultCode == Activity.RESULT_OK) {
            try {
                Toast.makeText(this, "允许录屏", Toast.LENGTH_SHORT).show();
            } catch (Exception e) {
                e.printStackTrace();
            }
        } else {
            Toast.makeText(this, "拒绝录屏", Toast.LENGTH_SHORT).show();
        }
    }
}
  1. 开启Service进行录制屏幕

由于应用在后台的时候仍然需要屏幕录制。

所以我们需要在Service 中进行操作。

在拿到确认录屏的权限之后，进行开启Service

综上所诉，该类完整代码如下

import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.media.projection.MediaProjectionManager;
import android.os.Build;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

import com.screen.recorder.demo.service.ScreenRecordService;

/**
 * @author by talon, Date on 19/6/23.
 * note:
 */
public class MainActivity extends AppCompatActivity {
    private static final int REQUEST_CODE = 1;
    private MediaProjectionManager mMediaProjectionManager;

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

        checkPermission(this); //检查权限

        mMediaProjectionManager = (MediaProjectionManager) getSystemService(MEDIA_PROJECTION_SERVICE);
    }

    public void StartRecorder(View view) {
        createScreenCapture();
    }

    public void StopRecorder(View view){
        Intent service = new Intent(this, ScreenRecordService.class);
        stopService(service);
    }


    public static void checkPermission(AppCompatActivity activity) {
        if (Build.VERSION.SDK_INT >= 23) {
            int checkPermission =
                    ContextCompat.checkSelfPermission(activity, Manifest.permission.RECORD_AUDIO)
                            + ContextCompat.checkSelfPermission(activity, Manifest.permission.READ_PHONE_STATE)
                            + ContextCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE)
                            + ContextCompat.checkSelfPermission(activity, Manifest.permission.READ_EXTERNAL_STORAGE);
            if (checkPermission != PackageManager.PERMISSION_GRANTED) {
                //动态申请
                ActivityCompat.requestPermissions(activity, new String[]{
                        Manifest.permission.RECORD_AUDIO,
                        Manifest.permission.READ_PHONE_STATE,
                        Manifest.permission.READ_EXTERNAL_STORAGE,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE}, 123);
            }
        }
    }


    private void createScreenCapture() {
        Intent captureIntent = mMediaProjectionManager.createScreenCaptureIntent();
        startActivityForResult(captureIntent, REQUEST_CODE);
    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_CODE && resultCode == Activity.RESULT_OK) {
            try {
                Toast.makeText(this, "允许录屏", Toast.LENGTH_SHORT).show();

                Intent service = new Intent(this, ScreenRecordService.class);
                service.putExtra("resultCode", resultCode);
                service.putExtra("data", data);
                startService(service);

            } catch (Exception e) {
                e.printStackTrace();
            }
        } else {
            Toast.makeText(this, "拒绝录屏", Toast.LENGTH_SHORT).show();
        }
    }

}

对应的视图代码如下

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开始录制"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:onClick="StartRecorder"/>


    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="停止录制"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:onClick="StopRecorder"/>

</LinearLayout>

2.3 在 Service 中进录制屏幕

  1. 拿到传递由onActivityResult回调产生的resultCode与data
mResultData = intent.getParcelableExtra("data");
  1. 获取手机屏幕的宽高与dpi
  2. 创建MediaProjection MediaRecorder VirtualDisplay

MediaRecorder 支持录屏时录音，主要是设置录屏过程中的参数。

VirtualDisplay 相当于一个虚拟显示器，调用DisplayManager 的createVirtualDisplay 方法后，此时虚拟显示器的内容会渲染在Surface上。 该主要是用来操作显示器，例如获取显示器，设置/得到surface，

  1. 在createMediaRecorder方法中配置保存视频的信息，文件的路径、文件名、清晰度等

比如设置录屏结束的文件名

mediaRecorder.setOutputFile(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES) + "/" + videoQuality + curTime + ".mp4");

该类代码如下

import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.hardware.display.DisplayManager;
import android.hardware.display.VirtualDisplay;
import android.media.MediaRecorder;
import android.media.projection.MediaProjection;
import android.media.projection.MediaProjectionManager;
import android.os.Environment;
import android.os.IBinder;
import android.util.Log;

import com.screen.recorder.demo.utils.ScreenUtils;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * @author by talon, Date on 19/6/23.
 * note:
 */
public class ScreenRecordService extends Service {

    private final String TAG = "ScreenRecordService";

    /**
     * 是否为标清视频
     */
    private boolean isVideoSd = false;

    private int mScreenWidth;
    private int mScreenHeight;
    private int mScreenDensity;

    private int mResultCode;
    private Intent mResultData;

    private MediaProjection mMediaProjection;
    private MediaRecorder mMediaRecorder;
    private VirtualDisplay mVirtualDisplay;

    public ScreenRecordService() {
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO: Return the communication channel to the service.
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        mResultCode = intent.getIntExtra("resultCode", 1);
        mResultData = intent.getParcelableExtra("data");

        getScreenBaseInfo();

        mMediaProjection = createMediaProjection();
        mMediaRecorder = createMediaRecorder();
        mVirtualDisplay = createVirtualDisplay(); // 必须在mediaRecorder.prepare() 之后调用，否则报错"fail to get surface"

        mMediaRecorder.start();
        return Service.START_NOT_STICKY;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.i(TAG, "onDestroy");
        if(mVirtualDisplay != null) {
            mVirtualDisplay.release();
            mVirtualDisplay = null;
        }
        if(mMediaRecorder != null) {
            mMediaRecorder.setOnErrorListener(null);
            mMediaProjection.stop();
            mMediaRecorder.reset();
        }
        if(mMediaProjection != null) {
            mMediaProjection.stop();
            mMediaProjection = null;
        }
    }

   
    /**
     * 获取屏幕相关数据
     */
    private void getScreenBaseInfo() {
        mScreenWidth = ScreenUtils.getScreenWidth(this);
        mScreenHeight = ScreenUtils.getScreenHeight(this);
        mScreenDensity = ScreenUtils.getScreenDensityDpi(this);
    }

    private MediaProjection createMediaProjection() {
        Log.i(TAG, "Create MediaProjection");
        return ((MediaProjectionManager) getSystemService(Context.MEDIA_PROJECTION_SERVICE)).getMediaProjection(mResultCode, mResultData);
    }


    private MediaRecorder createMediaRecorder() {
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");
        Date curDate = new Date(System.currentTimeMillis());
        String curTime = formatter.format(curDate).replace(" ", "");
        String videoQuality = "HD";
        if (isVideoSd) videoQuality = "SD";

        Log.i(TAG, "Create MediaRecorder");
        MediaRecorder mediaRecorder = new MediaRecorder();
//        if(isAudio) mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        mediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
        mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
        mediaRecorder.setOutputFile(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES) + "/" + videoQuality + curTime + ".mp4");
        mediaRecorder.setVideoSize(mScreenWidth, mScreenHeight);  //after setVideoSource(), setOutFormat()
        mediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);  //after setOutputFormat()
//        if(isAudio) mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);  //after setOutputFormat()
        int bitRate;
        if (isVideoSd) {
            mediaRecorder.setVideoEncodingBitRate(mScreenWidth * mScreenHeight);
            mediaRecorder.setVideoFrameRate(30);
            bitRate = mScreenWidth * mScreenHeight / 1000;
        } else {
            mediaRecorder.setVideoEncodingBitRate(5 * mScreenWidth * mScreenHeight);
            mediaRecorder.setVideoFrameRate(60); //after setVideoSource(), setOutFormat()
            bitRate = 5 * mScreenWidth * mScreenHeight / 1000;
        }
        try {
            mediaRecorder.prepare();
        } catch (IllegalStateException | IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return mediaRecorder;
    }

    private VirtualDisplay createVirtualDisplay() {
        Log.i(TAG, "Create VirtualDisplay");
        return mMediaProjection.createVirtualDisplay(TAG, mScreenWidth, mScreenHeight, mScreenDensity,
                DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR, mMediaRecorder.getSurface(), null, null);
    }
}

2.4 Demo下载地址

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