Android：截屏/视频截图

需求描述

实现截取Android应用当前界面的功能，需包含界面中视频（此博客的参考代码以存储在设备本地的视频为例，未检验在线视频的情况）当前的播放帧截图。

调研准备

首先应用需要获取设备存储的读写权限，需要在AndroidManifest.xml中加上请求权限的配置代码：

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

此外，Android原生的视频播放组件VideoView不支持修改视频的分辨率（视频分辨率与容器宽高不一致时，需要让视频拉伸填充容器），因此需要自己封装一个继承了VideoView的组件；在项目中新建一个MyVideoView.java，内容如下：

package XXX;import android.content.Context;
import android.media.MediaPlayer;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.VideoView;
import com.lzy.okgo.utils.HttpUtils;
import java.io.File;
import java.util.ArrayList;
import java.util.List;public class MyVideoView extends VideoView {private static final String TAG = "####MyVideoView ";// 记录当前播放视频的路径（用于截取播放帧）private String currentVideoUrl;public MyVideoView(Context paramContext) {super(paramContext);}public MyVideoView(Context paramContext, AttributeSet paramAttributeSet) {super(paramContext, paramAttributeSet);}public MyVideoView(Context paramContext, AttributeSet paramAttributeSet, int paramInt) {super(paramContext, paramAttributeSet, paramInt);}// 判断是否为视频文件public static boolean isVideo(String filePath) {filePath = filePath.toLowerCase();String[] vFiles = {".mov", ".mkv", ".mp4", ".avi"};for (byte vIdx = 0; vIdx < vFiles.length; vIdx++) {if (filePath.endsWith(vFiles[vIdx])) return true; } return false;}// 循环播放视频public void LoopPlayBack(final String videoPath) {File file = new File(videoPath);if (!file.exists() || !isVideo(videoPath)) return;// 开始播放视频this.currentVideoUrl = videoPath;setVideoPath(videoPath);start();// 视频播放完成，重新开始播放setOnCompletionListener(new MediaPlayer.OnCompletionListener() {  @Overridepublic void onCompletion(MediaPlayer mp) {MyVideoView.this.start();}});// 视频播放报错监听setOnErrorListener(new MediaPlayer.OnErrorListener() {@Overridepublic boolean onError(MediaPlayer mp) {Log.d(TAG, "播放错误..");return false;}});}public String getCurrentVideoUrl() { // 获取视频文件路径（用于截取播放帧）return this.currentVideoUrl;}protected void onMeasure(int paramInt1, int paramInt2) { // 调整视频分辨率，使视频拉伸填充容器setMeasuredDimension(getDefaultSize(getWidth(), paramInt1), getDefaultSize(getHeight(), paramInt2));}
}

在相应的布局.xml中使用MyVideoView视频组件：
P.S.如果要实现圆角视频效果，可以在MyVideoView外再套一层CardView，可参考：CardView-卡片布局

<LinearLayoutandroid:orientation="horizontal"android:layout_width="800.0px"android:layout_height="600.0px"
><XXX.MyVideoViewandroid:id="@id/video"android:visibility="visible"android:layout_width="fill_parent"android:layout_height="fill_parent"android:layout-align-parent-top="true"/>
</LinearLayout>

参考代码

如果界面中有视频播放，使用getDrawingCache截取整个应用界面时，视频区域会显示为黑屏；因此要另外获取视频当前的播放帧，再通过Canvas绘制Bitmap将视频截图“粘贴”到界面截图相应区域，从而实现截取整个界面（包括视频）的效果：

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Rect;
import android.media.MediaMetadataRetriever;// 调用此函数进行完整截屏（参数：本地视频路径）
private void taskScreenshot(String videoPath) {try {Bitmap screenPic = takeScreenBitmap(); // 屏幕截图Bitmap videoPic = getCurrentVideoBitmap(this.myVideoView); // 视频截图if (screenPic != null) {Bitmap wholePic = screenPic; // 完整截图（默认取屏幕截图）if (videoPic != null) // 如果获取到了视频截图，完整截图由屏幕截图“粘贴”视频截图得到wholePic = mergeBitmap(screenPic, scaleBitmap(videoPic, 2), 0, 2); // 获取截图保存路径String picPath = Environment.getExternalStorageDirectory().getPath() + "/screenshot/testPic.png";File picFile = new File(picPath);if (picFile.exists())picFile.delete(); FileOutputStream fileOutputStream = new FileOutputStream();// 保存截图wholePic.compress(Bitmap.CompressFormat.PNG, 80, fileOutputStream);fileOutputStream.flush();fileOutputStream.close();} } catch (Exception e) {} 
}// 截屏（不包含视频）
private Bitmap takeScreenBitmap() {int width = getWindow().getDecorView().getRootView().getWidth();int height = getWindow().getDecorView().getRootView().getHeight();View view = getWindow().getDecorView().getRootView();view.setDrawingCacheEnabled(false);view.buildDrawingCache();Bitmap bitmap = Bitmap.createBitmap(view.getDrawingCache(), 0, 0, width, height);view.destroyDrawingCache();return bitmap;
}// 截取视频关键帧
public static Bitmap getCurrentVideoBitmap(MyVideoView paramMyVideoView) {Bitmap bitmap = null;MediaMetadataRetriever mediaMetadataRetriever = new MediaMetadataRetriever();String videoPath = paramMyVideoView.getCurrentVideoUrl();try {if (Build.VERSION.SDK_INT >= 24) {Uri uri = Uri.parse(videoPath);mediaMetadataRetriever.setDataSource(this, uri);} else {FileInputStream fileInputStream = new FileInputStream();File file = new File();this(videoPath);this(file.getAbsolutePath());mediaMetadataRetriever.setDataSource(fileInputStream.getFD());} bitmap = mediaMetadataRetriever.getFrameAtTime((paramMyVideoView.getCurrentPosition() * 1000), MediaMetadataRetriever.OPTION_CLOSEST);}catch (Exception e) { }finally {try {mediaMetadataRetriever.release();} catch (RuntimeException runtimeException1) {stringBuilder = new StringBuilder();stringBuilder.append("getCurrentVideoBitmap-RuntimeException2:");stringBuilder.append(runtimeException1.getMessage());StoreData.appendLogFile("####FullscreenActivity ", stringBuilder.toString());}return (bitmap == null) ? null : Bitmap.createBitmap(bitmap);}
}// bitmap变换：截取的视频截图尺寸和页面容器可能不一致，需拉伸为容器尺寸
private Bitmap scaleBitmap(Bitmap paramBitmap, float cWidth, float cHeight) {if (paramBitmap == null)return null; int vWidth = paramBitmap.getWidth();int vHeight = paramBitmap.getHeight();Matrix matrix = new Matrix();matrix.postScale(cWidth / vWidth, cHeight / vHeight);Bitmap bitmap = Bitmap.createBitmap(paramBitmap, 0, 0, vWidth, vHeight, matrix, false);if (!paramBitmap.isRecycled()) paramBitmap.recycle(); return bitmap;
}// bitmap变换：将视频截图“粘贴”到屏幕截图的对应区域
private Bitmap mergeBitmap(Bitmap paramBitmap1, Bitmap paramBitmap2, int[] size1, int[] size2) {int width1 = size1[0], height1 = size1[1];int width2 = size2[0], height2 = size2[1];// 创建与屏幕截图大小一样的画布，然后分别将屏幕截图、视频截图绘制到画布对应位置Bitmap bitmap = Bitmap.createBitmap(width1, height1, Bitmap.Config.RGB_565);Canvas canvas = new Canvas(bitmap);canvas.drawBitmap(paramBitmap1, new Rect(0, 0, width1, height1), new Rect(0, 0, width1, height1), null);canvas.drawBitmap(paramBitmap2, new Rect(0, 0, width2, height2), new Rect(0, 0, width2, height2), null);return bitmap;
}

参考文档
[1] Android播放网络视频截图
[2] setDataSource RuntimeException 0xFFFFFFEA
[3] Android Bitmap相关操作
[4] Android使用Canvas绘制Bitmap相关
[5] CardView-卡片布局