14

我有一个应用程序,我希望能够捕获屏幕截图。布局的背景是一个显示后置摄像头视频的表面视图。下面的代码可以截图但是surfaceView的内容被保存为黑色。这是代码:

btn.setOnClickListener(new OnClickListener()
{

public void onClick(View v)
{
    Random num = new Random();
    int nu=num.nextInt(1000);
    Bitmap bmp;
    CamView.setDrawingCacheEnabled(true); 
    CamView.buildDrawingCache(true);
    Bitmap bmp2 = Bitmap.createBitmap(CamView.getDrawingCache()); //Screenshot of the layout
    CamView.setDrawingCacheEnabled(false);

    SurView.setDrawingCacheEnabled(true); 
    SurView.buildDrawingCache(true);
    Bitmap bmp1 = Bitmap.createBitmap(SurView.getDrawingCache()); //Screenshot of the surfaceView
    SurView.setDrawingCacheEnabled(false);

    Bitmap bmOverlay = Bitmap.createBitmap(bmp1.getWidth(), bmp1.getHeight(),bmp1.getConfig());
    Canvas canvas = new Canvas(bmOverlay); //Overlaying the 2 bitmaps
    canvas.drawBitmap(bmp1, 0,0, null);
    canvas.drawBitmap(bmp2, 0,0, null);
    bmp=bmOverlay;

    //saving the file
    ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
    bmp.compress(CompressFormat.JPEG, 100, bos); 
    byte[] bitmapdata = bos.toByteArray();
    ByteArrayInputStream fis = new ByteArrayInputStream(bitmapdata);

    String picId=String.valueOf(nu);
    String myfile="Ghost"+picId+".jpeg";

    File dir_image = new  File(Environment.getExternalStorageDirectory()+
            File.separator+"Ultimate Entity Detector");
    dir_image.mkdirs();

    try {
        File tmpFile = new File(dir_image,myfile); 
        FileOutputStream fos = new FileOutputStream(tmpFile);

         byte[] buf = new byte[1024];
            int len;
            while ((len = fis.read(buf)) > 0) {
                fos.write(buf, 0, len);
            }
                fis.close();
                fos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}
});

我更新了代码。现在我创建2个位图,1个用于布局xml,1个用于surfaceView,然后我将它们叠加到一个位图中。但是surfaceView位图还是黑的

4

2 回答 2

12

我终于解决了这个问题。下面我为任何想知道如何截取布局的屏幕截图、无意从相机拍摄的图片、surfaceView 内容的屏幕截图(某种)并将屏幕截图保存在文件夹中的人提供一些代码:

public class Cam_View extends Activity implements SurfaceHolder.Callback {

    protected static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 0;
    private SurfaceView SurView;
    private SurfaceHolder camHolder;
    private boolean previewRunning;
    final Context context = this;
    public static Camera camera = null;
    private RelativeLayout CamView;
    private Bitmap inputBMP = null, bmp, bmp1;
    private ImageView mImage;

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

        CamView = (RelativeLayout) findViewById(R.id.camview);//RELATIVELAYOUT OR 
                                                              //ANY LAYOUT OF YOUR XML

        SurView = (SurfaceView)findViewById(R.id.sview);//SURFACEVIEW FOR THE PREVIEW 
                                                        //OF THE CAMERA FEED
        camHolder = SurView.getHolder();                           //NEEDED FOR THE PREVIEW
        camHolder.addCallback(this);                               //NEEDED FOR THE PREVIEW
        camHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);//NEEDED FOR THE PREVIEW
        camera_image = (ImageView) findViewById(R.id.camera_image);//NEEDED FOR THE PREVIEW

        Button btn = (Button) findViewById(R.id.button1); //THE BUTTON FOR TAKING PICTURE

        btn.setOnClickListener(new OnClickListener() {    //THE BUTTON CODE
            public void onClick(View v) {
                  camera.takePicture(null, null, mPicture);//TAKING THE PICTURE
                                                         //THE mPicture IS CALLED 
                                                         //WHICH IS THE LAST METHOD(SEE BELOW)
            }
        });
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width,//NEEDED FOR THE PREVIEW
        int height) {
        if(previewRunning) {
            camera.stopPreview();
        }
        Camera.Parameters camParams = camera.getParameters();
        Camera.Size size = camParams.getSupportedPreviewSizes().get(0);
        camParams.setPreviewSize(size.width, size.height);
        camera.setParameters(camParams);
        try {
            camera.setPreviewDisplay(holder);
            camera.startPreview();
            previewRunning=true;
        } catch(IOException e) {
            e.printStackTrace();
        }
    }

    public void surfaceCreated(SurfaceHolder holder) {                  //NEEDED FOR THE PREVIEW
        try {
            camera=Camera.open();
        } catch(Exception e) {
            e.printStackTrace();
            Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            finish();
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {             //NEEDED FOR THE PREVIEW
        camera.stopPreview();
        camera.release();
        camera=null;
    }

    public void TakeScreenshot(){    //THIS METHOD TAKES A SCREENSHOT AND SAVES IT AS .jpg
        Random num = new Random();
        int nu=num.nextInt(1000); //PRODUCING A RANDOM NUMBER FOR FILE NAME
        CamView.setDrawingCacheEnabled(true); //CamView OR THE NAME OF YOUR LAYOUR
        CamView.buildDrawingCache(true);
        Bitmap bmp = Bitmap.createBitmap(CamView.getDrawingCache());
        CamView.setDrawingCacheEnabled(false); // clear drawing cache
        ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
        bmp.compress(CompressFormat.JPEG, 100, bos); 
        byte[] bitmapdata = bos.toByteArray();
        ByteArrayInputStream fis = new ByteArrayInputStream(bitmapdata);

        String picId=String.valueOf(nu);
        String myfile="Ghost"+picId+".jpeg";

        File dir_image = new  File(Environment.getExternalStorageDirectory()+//<---
                        File.separator+"Ultimate Entity Detector");          //<---
        dir_image.mkdirs();                                                  //<---
        //^IN THESE 3 LINES YOU SET THE FOLDER PATH/NAME . HERE I CHOOSE TO SAVE
        //THE FILE IN THE SD CARD IN THE FOLDER "Ultimate Entity Detector"

        try {
            File tmpFile = new File(dir_image,myfile); 
            FileOutputStream fos = new FileOutputStream(tmpFile);

            byte[] buf = new byte[1024];
            int len;
            while ((len = fis.read(buf)) > 0) {
                fos.write(buf, 0, len);
            }
            fis.close();
            fos.close();
            Toast.makeText(getApplicationContext(),
                           "The file is saved at :SD/Ultimate Entity Detector",Toast.LENGTH_LONG).show();
            bmp1 = null;
            camera_image.setImageBitmap(bmp1); //RESETING THE PREVIEW
            camera.startPreview();             //RESETING THE PREVIEW
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private PictureCallback mPicture = new PictureCallback() {   //THIS METHOD AND THE METHOD BELOW
                                 //CONVERT THE CAPTURED IMAGE IN A JPG FILE AND SAVE IT

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {

            File dir_image2 = new  File(Environment.getExternalStorageDirectory()+
                            File.separator+"Ultimate Entity Detector");
            dir_image2.mkdirs();  //AGAIN CHOOSING FOLDER FOR THE PICTURE(WHICH IS LIKE A SURFACEVIEW
                                  //SCREENSHOT)

            File tmpFile = new File(dir_image2,"TempGhost.jpg"); //MAKING A FILE IN THE PATH
                            //dir_image2(SEE RIGHT ABOVE) AND NAMING IT "TempGhost.jpg" OR ANYTHING ELSE
            try { //SAVING
                FileOutputStream fos = new FileOutputStream(tmpFile);
                fos.write(data);
                fos.close();
                //grabImage();
            } catch (FileNotFoundException e) {
                Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            } catch (IOException e) {
                Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
            }

            String path = (Environment.getExternalStorageDirectory()+
                            File.separator+"Ultimate EntityDetector"+
                                                File.separator+"TempGhost.jpg");//<---

            BitmapFactory.Options options = new BitmapFactory.Options();//<---
                options.inPreferredConfig = Bitmap.Config.ARGB_8888;//<---
            bmp1 = BitmapFactory.decodeFile(path, options);//<---     *********(SEE BELOW)
            //THE LINES ABOVE READ THE FILE WE SAVED BEFORE AND CONVERT IT INTO A BitMap
            camera_image.setImageBitmap(bmp1); //SETTING THE BitMap AS IMAGE IN AN IMAGEVIEW(SOMETHING
                                        //LIKE A BACKGROUNG FOR THE LAYOUT)

            tmpFile.delete();
            TakeScreenshot();//CALLING THIS METHOD TO TAKE A SCREENSHOT
            //********* THAT LINE MIGHT CAUSE A CRASH ON SOME PHONES (LIKE XPERIA T)<----(SEE HERE)
            //IF THAT HAPPENDS USE THE LINE "bmp1 =decodeFile(tmpFile);" WITH THE METHOD BELOW

        }
    };

    public Bitmap decodeFile(File f) {  //FUNCTION BY Arshad Parwez
        Bitmap b = null;
        try {
            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;

            FileInputStream fis = new FileInputStream(f);
            BitmapFactory.decodeStream(fis, null, o);
            fis.close();
            int IMAGE_MAX_SIZE = 1000;
            int scale = 1;
            if (o.outHeight > IMAGE_MAX_SIZE || o.outWidth > IMAGE_MAX_SIZE) {
                scale = (int) Math.pow(
                        2,
                        (int) Math.round(Math.log(IMAGE_MAX_SIZE
                                / (double) Math.max(o.outHeight, o.outWidth))
                                / Math.log(0.5)));
            }

            // Decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            fis = new FileInputStream(f);
            b = BitmapFactory.decodeStream(fis, null, o2);
            fis.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return b;
    }
}

如果你想拍一张简单的截图(不需要相机),你可以单独使用 TakeScreenshot 方法。

如果您想截取surfaceView的屏幕截图,并且无法直接从surfaceview执行,请使用mPicture,将您捕获的图片设置为backgroung,然后调用TakeScreenshot来截取您的屏幕截图。(如上所示)

如果您想用相机拍照而不用意图调用其他相机应用程序,请使用带有 mPicture 的 takePicture 和上面代码中的 surfaceView 内容。

如果“按原样”使用,前面的代码的作用是截取布局内容(按钮、图像视图等)并将来自相机的图像设置为背景。

下面我还为前面的代码提供了一个基本的布局 xml:

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

<SurfaceView
    android:id="@+id/sview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true" />

<ImageView
    android:id="@+id/camera_image"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:contentDescription="@string/app_name" />



<Button
    android:id="@+id/button1"
    style="?android:attr/buttonStyleSmall"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true" />


</RelativeLayout>

不要忘记导入需要导入的内容

于 2013-08-18T12:49:14.420 回答
3

根据 Android 框架工程师的评论 ( https://groups.google.com/forum/#!topic/android-developers/jYjvm7ItpXQ),SurfaceView不被视为普通视图:

表面视图实际上是在您的窗户后面,并且在窗户上打了一个孔供您查看。因此,您可以将东西放在窗口的顶部,但窗口中的任何内容都不会出现在其后面。

由于它在应用程序窗口的“后面”,因此窗口视图的绘图不会包含它。我想唯一的方法是在 SurfaceView 类中提供一个方法来将自己的内容绘制到提供的 Canvas/Bitmap。

于 2013-08-17T14:24:29.940 回答