Android 截屏实现的几种方式

向右看齐 2023-09-27 16:47 150阅读 0赞

## Android 截屏分为四种：View 截屏、WebView 截屏、系统截屏 和 adb 截屏 ##

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#### 1、View 截屏 ####

View 截图是将当前 View 界面截取下来，而对于屏幕上其他信息比如：状态栏或其他应用的界面将无法截取。

#### 1.1 截取除了导航栏之外的屏幕 ####

// 开始截屏
        private static byte[] screenshotView() {
    
            // ⬇⬇⬇ 可直接放入点击事件中 ⬇⬇⬇
            View view = getWindow().getDecorView(); // view可以替换成你需要截图的控件，如父控件 RelativeLayout，LinearLayout
            // view.setDrawingCacheEnabled(true); // 设置缓存，可用于实时截图
            Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.ARGB_8888);
            Canvas canvas = new Canvas(bitmap);
            view.draw(canvas);
            // view.setDrawingCacheEnabled(false); // 清空缓存，可用于实时截图
    
            String bitmapString = getBitmapString(bitmap); // 位图转 Base64 String
            // byte[] drawByte = getBitmapByte(bitmap); // 位图转为 Byted
    
            Log.d("111111 合并>>", "bitmapString ====:" + bitmapString);
            matting_img02.setImageBitmap(bitmap); // ImageView控件直接图片展示截好的图片
            // ⬆⬆⬆ 可直接放入点击事件中 ⬆⬆⬆
    
            return drawByte;
        }
    
        // 位图转 Base64 String
        private static String getBitmapString(Bitmap bitmap) {
            String result = null;
            ByteArrayOutputStream out = null;
            try {
                if (bitmap != null) {
                    out = new ByteArrayOutputStream();
                    bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
    
                    out.flush();
                    out.close();
    
                    byte[] bitmapBytes = out.toByteArray();
                    result = Base64.encodeToString(bitmapBytes, Base64.DEFAULT); // Base64.DEFAULT会自动换行，传给前端会报错，所以要用Base64.NO_WRAP
                }
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    if (out != null) {
                        out.flush();
                        out.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return result;
        }
    
        // 位图转 Byte
        private static byte[] getBitmapByte(Bitmap bitmap) {
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            // 参数1转换类型，参数2压缩质量，参数3字节流资源
            bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
            try {
                out.flush();
                out.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return out.toByteArray();
        }

--------------------

#### 1.2 截取某个控件或者区域 ####

// 方法1
    private static byte[] screenshotView1() {
      View view = title;
      view.setDrawingCacheEnabled(true);
      view.buildDrawingCache();
      Bitmap bitmap = Bitmap.createBitmap(view.getDrawingCache());
      byte[] drawByte = getBitmapByte(bitmap);
      return drawByte;
    }
    
    // 方法2
    private static byte[] screenshotView2() {
      View view = title;
      Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.ARGB_8888);
      // 使用 Canvas，调用自定义 view 控件的 onDraw 方法，绘制图片
      Canvas canvas = new Canvas(bitmap);
      dView.draw(canvas);
      byte[] drawByte = getBitmapByte(bitmap);
      return drawByte;
    }

#### 2、WebView 截屏 ####

WebView 截屏有四种方式

2.1 使用 capturePicture() 方法（已废弃）  
private static byte\[\] screenshotWebView() \{  
Picture picture = webview.capturePicture();  
//创建位图  
Bitmap bitmap = Bitmap.createBitmap(picture.getWidth(), picture.getHeight(), Bitmap.Config.ARGB\_8888);  
Canvas canvas = new Canvas(bitmap);  
// 绘制(会调用 native 方法，完成图形绘制)  
picture.draw(canvas);  
byte\[\] drawByte = getBitmapByte(bitmap);  
return drawByte;  
\}

#### 2.2 使用 getScale() 方法（已废弃） ####

private static byte\[\] screenshotWebView() \{  
float scale = webView.getScale();  
int webViewHeight = (int) (webView.getContentHeight()\*scale+0.5);  
Bitmap bitmap = Bitmap.createBitmap(webView.getWidth(),webViewHeight, Bitmap.Config.ARGB\_8888);  
Canvas canvas = new Canvas(bitmap);  
webView.draw(canvas);  
byte\[\] drawByte = getBitmapByte(bitmap);  
return drawByte;  
\}

#### 2.3 使用 getDrawingCache() 方法 ####

private static byte\[\] screenshotWebView() \{  
Bitmap bitmap = webView.getDrawingCache();  
byte\[\] drawByte = getBitmapByte(bmp);  
return drawByte;  
\}

#### 2.4 使用 draw() 方法 ####

private static byte\[\] screenshotWebView() \{  
// webView.setDrawingCacheEnabled(true); // 设置缓存  
Bitmap bitmap = Bitmap.createBitmap(webView.getWidth(), webView.getHeight(), Bitmap.Config.ARGB\_8888);  
Canvas canvas = new Canvas(bitmap);  
webView.draw(canvas);  
webView.destroyDrawingCache();  
byte\[\] drawByte = getBitmapByte(bitmap);  
// webView.setDrawingCacheEnabled(false); // 清空缓存  
return drawByte;  
\}

#### 2.5 截长图配置 ####

if (Build.VERSION.SDK\_INT >= Build.VERSION\_CODES.LOLLIPOP) \{  
WebView.enableSlowWholeDocumentDraw();  
\}  
setContentView(R.layout.activity\_webview);

WebView 截图可能截取不到 cavans 元素，原因是开启了硬件加速，可在 AndroidManifest.xml 中设置属性 android:hardwareAccelerated="false"

关闭硬件加速可能导致页面出现意外情况

#### 3、系统截屏 ####

#### 3.1 MediaProjection ####

public static final int REQUEST\_MEDIA\_PROJECTION = 10001;  
// 申请截屏权限  
private void getScreenShotPower() \{  
if (Build.VERSION.SDK\_INT >= Build.VERSION\_CODES.M) \{  
MediaProjectionManager mProjectionManager = (MediaProjectionManager) getSystemService(Context.MEDIA\_PROJECTION\_SERVICE);  
if (mProjectionManager != null) \{  
startActivityForResult(mProjectionManager.createScreenCaptureIntent(), REQUEST\_MEDIA\_PROJECTION);  
\}  
\}  
\}

private MediaProjection mMediaProjection;  
// 回调  
@Override  
protected void onActivityResult(int requestCode, int resultCode, Intent data) \{  
super.onActivityResult(requestCode, resultCode, data);  
if (requestCode == REQUEST\_MEDIA\_PROJECTION && data != null) \{  
if (resultCode == RESULT\_OK) \{  
MediaProjection mediaProjection = mMediaProjectionManager.getMediaProjection(resultCode, data);  
if (mediaProjection == null) \{  
Toast.makeText(this,"程序发生错误:MediaProjection@1",Toast.LENGTH\_SHORT).show();  
return;  
\}  
// mediaProjection 就是当前屏幕流  
\} else if (resultCode == RESULT\_CANCELED) \{  
Log.d(TAG, "用户取消");  
\}  
\}  
\}

#### 3.2 Surface（需要 root 权限） ####

使用前需要：

在 AndroidMenifest.xml 中添加 android:sharedUserId="android.uid.system" 属性  
需要给程序添加系统签名  
或者 root 系统  
使用 Java 反射机制，调用系统 API 截图：

private void screenshotSystem() \{  
Class<?> surfaceClass;  
Method method = null;  
Bitmap bitmap = null;  
try \{  
if (android.os.Build.VERSION.SDK\_INT >= android.os.Build.VERSION\_CODES.JELLY\_BEAN\_MR2) \{  
surfaceClass = Class.forName("android.view.SurfaceControl");  
\} else \{  
surfaceClass = Class.forName("android.view.Surface");  
\}  
method = surfaceClass.getDeclaredMethod("screenshot", Integer.TYPE, Integer.TYPE);  
method.setAccessible(true);  
bitmap = (Bitmap)method.invoke((Object)null, webview.getWidth(), webview.getHeight());  
byte\[\] drawByte = getBitmapByte(bitmap);  
\} catch (ClassNotFoundException e)\{  
e.printStackTrace();  
\} catch (NoSuchMethodException e)\{  
e.printStackTrace();  
\} catch (IllegalAccessException e)\{  
e.printStackTrace();  
\} catch (InvocationTargetException e)\{  
e.printStackTrace();  
\}  
\}

#### 3.3 PixelCopy ####

private void screenshotSystem() \{  
if (Build.VERSION.SDK\_INT >= Build.VERSION\_CODES.O) \{  
PixelCopy.request(getWindow(), bitmap, new PixelCopy.OnPixelCopyFinishedListener() \{  
@Override  
public void onPixelCopyFinished(int copyResult)\{  
if (PixelCopy.SUCCESS == copyResult) \{  
byte\[\] drawByte = getBitmapByte(bitmap);  
\} else \{  
// onErrorCallback()  
\}  
\}  
\}, new Handler());  
\}  
\}

#### 3.4 framebuffer（需要 root 权限） ####

String DEVICE\_NAME = "/dev/graphics/fb0";  
File deviceFile = new File(DEVICE\_NAME);  
Process localProcess = Runtime.getRuntime().exec("supersu");  
String str = "cat " + deviceFile.getAbsolutePath() + "\\n";  
localProcess.getOutputStream().write(str.getBytes());  
return localProcess.getInputStream();

#### 3.5 screencap 命令（需要 root 权限） ####

private static String getScreenshot()\{  
Process process = null;  
String filePath = "mnt/sdcard/" + System.currentTimeMillis() + ".png";  
try \{  
process = Runtime.getRuntime().exec("su");  
PrintStream outputStream = null;  
outputStream = new PrintStream(new BufferedOutputStream(process.getOutputStream(), 8192));  
outputStream.println("screencap -p " + filePath);  
outputStream.flush();  
outputStream.close();  
process.waitFor();  
\} catch (Exception e) \{  
e.printStackTrace();  
\} finally \{  
if(process != null)\{  
process.destroy();  
\}  
\}  
return filePath;  
\}

#### 4、adb 截屏 ####

$ adb shell
    shell@ $ screencap /sdcard/screen.png
    shell@ $ exit
    $ adb pull /sdcard/screen.png

[75bf4c86c9983de163e2a12bb72df70d.png]: https://img-blog.csdnimg.cn/img_convert/75bf4c86c9983de163e2a12bb72df70d.png
[62e520d6075f77977b2d9ac3c2067a1c.png]: https://img-blog.csdnimg.cn/img_convert/62e520d6075f77977b2d9ac3c2067a1c.png