Größere Kameravorschau mit der ZBar-Scannerbibliothek in Android

Question

Ich verwende ZBarScannerActivity in meiner Android-App. aber ich bekomme eine kleine Oberflächenansicht auf dem Gerät. Eigentlich möchte ich Vollbildkamera-Vorschau den QR-Code scannen.

Jede Hilfe wäre willkommen. Danke. hier ist der Code von ZbarScanner Aktivität

package com.dm.zbar.android.scanner; 


public class ZBarScannerActivity extends Activity implements Camera.PreviewCallback, ZBarConstants { 

private static final String TAG = "ZBarScannerActivity"; 
private CameraPreview mPreview; 
private Camera mCamera; 
private ImageScanner mScanner; 
private Handler mAutoFocusHandler; 
private boolean mPreviewing = true; 

static { 
    System.loadLibrary("iconv"); 
} 

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

    if(!isCameraAvailable()) { 
     // Cancel request if there is no rear-facing camera. 
     cancelRequest(); 
     return; 
    } 


    // Hide the window title. 
    //requestWindowFeature(Window.FEATURE_NO_TITLE); 
    //getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN); 


    mAutoFocusHandler = new Handler(); 

    // Create and configure the ImageScanner; 
    setupScanner(); 

    // Create a RelativeLayout container that will hold a SurfaceView, 
    // and set it as the content of our activity. 
    mPreview = new CameraPreview(this, this, autoFocusCB); 
    setContentView(mPreview); 
} 




public void setupScanner() { 
    mScanner = new ImageScanner(); 
    mScanner.setConfig(0, Config.X_DENSITY, 3); 
    mScanner.setConfig(0, Config.Y_DENSITY, 3); 

    int[] symbols = getIntent().getIntArrayExtra(SCAN_MODES); 
    if (symbols != null) { 
     mScanner.setConfig(Symbol.NONE, Config.ENABLE, 0); 
     for (int symbol : symbols) { 
      mScanner.setConfig(symbol, Config.ENABLE, 1); 
     } 
    } 
} 

@Override 
protected void onResume() { 
    super.onResume(); 

    // Open the default i.e. the first rear facing camera. 
    mCamera = Camera.open(); 
    if(mCamera == null) { 
     // Cancel request if mCamera is null. 
     cancelRequest(); 
     return; 
    } 

    mPreview.setCamera(mCamera); 
    mPreview.showSurfaceView(); 

    mPreviewing = true; 
} 

@Override 
protected void onPause() { 
    super.onPause(); 

    // Because the Camera object is a shared resource, it's very 
    // important to release it when the activity is paused. 
    if (mCamera != null) { 
     mPreview.setCamera(null); 
     mCamera.cancelAutoFocus(); 
     mCamera.setPreviewCallback(null); 
     mCamera.stopPreview(); 
     mCamera.release(); 

     // According to Jason Kuang on http://stackoverflow.com/questions/6519120/how-to-recover-camera-preview-from-sleep, 
     // there might be surface recreation problems when the device goes to sleep. So lets just hide it and 
     // recreate on resume 
     mPreview.hideSurfaceView(); 

     mPreviewing = false; 
     mCamera = null; 
    } 
} 

public boolean isCameraAvailable() { 
    PackageManager pm = getPackageManager(); 
    return pm.hasSystemFeature(PackageManager.FEATURE_CAMERA); 
} 

public void cancelRequest() { 
    Intent dataIntent = new Intent(); 
    dataIntent.putExtra(ERROR_INFO, "Camera unavailable."); 
    setResult(Activity.RESULT_CANCELED, dataIntent); 
    finish(); 
} 

public void onPreviewFrame(byte[] data, Camera camera) { 
    Camera.Parameters parameters = camera.getParameters(); 
    Camera.Size size = parameters.getPreviewSize(); 

    Image barcode = new Image(size.width, size.height, "Y800"); 
    barcode.setData(data); 

    int result = mScanner.scanImage(barcode); 

    if (result != 0) { 
     mCamera.cancelAutoFocus(); 
     mCamera.setPreviewCallback(null); 
     mCamera.stopPreview(); 
     mPreviewing = false; 
     SymbolSet syms = mScanner.getResults(); 
     for (Symbol sym : syms) { 
      String symData = sym.getData(); 
      if (!TextUtils.isEmpty(symData)) { 
       Intent dataIntent = new Intent(); 
       dataIntent.putExtra(SCAN_RESULT, symData); 
       dataIntent.putExtra(SCAN_RESULT_TYPE, sym.getType()); 
       setResult(Activity.RESULT_OK, dataIntent); 
       finish(); 
       break; 
      } 
     } 
    } 
} 
private Runnable doAutoFocus = new Runnable() { 
    public void run() { 
     if(mCamera != null && mPreviewing) { 
      mCamera.autoFocus(autoFocusCB); 
     } 
    } 
}; 

// Mimic continuous auto-focusing 
Camera.AutoFocusCallback autoFocusCB = new Camera.AutoFocusCallback() { 
    public void onAutoFocus(boolean success, Camera camera) { 
     mAutoFocusHandler.postDelayed(doAutoFocus, 1000); 
    } 
}; 

und CameraPreview Klasse Klasse CameraPreview Viewgroup implementiert SurfaceHolder.Callback { Privat final String TAG = "CameraPreview" erstreckt;

SurfaceView mSurfaceView; 
SurfaceHolder mHolder; 
Size mPreviewSize; 
List<Size> mSupportedPreviewSizes; 
Camera mCamera; 
PreviewCallback mPreviewCallback; 
AutoFocusCallback mAutoFocusCallback; 

CameraPreview(Context context, PreviewCallback previewCallback, AutoFocusCallback autoFocusCb) { 
    super(context); 

    mPreviewCallback = previewCallback; 
    mAutoFocusCallback = autoFocusCb; 
    mSurfaceView = new SurfaceView(context); 
    addView(mSurfaceView); 

    // Install a SurfaceHolder.Callback so we get notified when the 
    // underlying surface is created and destroyed. 
    mHolder = mSurfaceView.getHolder(); 
    mHolder.addCallback(this); 
    mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); 
} 

public void setCamera(Camera camera) { 
    mCamera = camera; 
    if (mCamera != null) { 
     //Changes******** 
     mCamera.setDisplayOrientation(90); 
     mCamera.getParameters().getMaxNumFocusAreas(); 
     mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes(); 

     requestLayout(); 
    } 
} 

@Override 
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 

    // We purposely disregard child measurements because act as a 
    // wrapper to a SurfaceView that centers the camera preview instead 
    // of stretching it. 



    final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec); 
    final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec); 
    setMeasuredDimension(width, height); 

    if (mSupportedPreviewSizes != null) { 
     mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height); 
    } 
} 

@Override 
protected void onLayout(boolean changed, int l, int t, int r, int b) { 
    if (changed && getChildCount() > 0) { 
     final View child = getChildAt(0); 


     final int width = r - l; 
     final int height = b - t; 

     int previewWidth = width; 
     int previewHeight = height; 
     if (mPreviewSize != null) { 
      previewWidth = mPreviewSize.width; 
      previewHeight = mPreviewSize.height; 
     } 

     // Center the child SurfaceView within the parent. 
     if (width * previewHeight > height * previewWidth) { 
      final int scaledChildWidth = previewWidth * height/previewHeight; 
      child.layout((width - scaledChildWidth)/2, 0, 
        (width + scaledChildWidth)/2, height); 
     } else { 
      final int scaledChildHeight = previewHeight * width/previewWidth; 
      child.layout(0, (height - scaledChildHeight)/2, 
        width, (height + scaledChildHeight)/2); 
     } 
    } 
} 

public void hideSurfaceView() { 
    mSurfaceView.setVisibility(View.INVISIBLE); 
} 

public void showSurfaceView() { 
    mSurfaceView.setVisibility(View.VISIBLE); 
} 

public void surfaceCreated(SurfaceHolder holder) { 
    // The Surface has been created, acquire the camera and tell it where 
    // to draw. 
    try { 
     if (mCamera != null) { 
      mCamera.setPreviewDisplay(holder); 
     } 
    } catch (IOException exception) { 
     Log.e(TAG, "IOException caused by setPreviewDisplay()", exception); 
    } 
} 

public void surfaceDestroyed(SurfaceHolder holder) { 
    // Surface will be destroyed when we return, so stop the preview. 
    if (mCamera != null) { 
     mCamera.cancelAutoFocus(); 
     mCamera.stopPreview(); 
    } 
} 


private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) { 
    final double ASPECT_TOLERANCE = 0.1; 
    double targetRatio = (double) w/h; 
    if (sizes == null) return null; 

    Size optimalSize = null; 
    double minDiff = Double.MAX_VALUE; 

    int targetHeight = h; 

    // Try to find an size match aspect ratio and size 

    for (Size size : sizes) { 
     double ratio = (double) size.width/size.height; 
     if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue; 
     if (Math.abs(size.height - targetHeight) < minDiff) { 
      optimalSize = size; 
      minDiff = Math.abs(size.height - targetHeight); 
     } 
    } 

    // Cannot find the one match the aspect ratio, ignore the requirement 
    if (optimalSize == null) { 
     minDiff = Double.MAX_VALUE; 
     for (Size size : sizes) { 
      if (Math.abs(size.height - targetHeight) < minDiff) { 
       optimalSize = size; 
       minDiff = Math.abs(size.height - targetHeight); 
      } 
     } 
    } 
    return optimalSize; 
} 

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { 
    if (holder.getSurface() == null){ 
     // preview surface does not exist 
     return; 
    } 

    if (mCamera != null) { 
     // Now that the size is known, set up the camera parameters and begin 
     // the preview. 
     Camera.Parameters parameters = mCamera.getParameters(); 
     parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height); 
     requestLayout(); 

     // mCamera.setDisplayOrientation(90); 
     mCamera.setParameters(parameters); 
     mCamera.setPreviewCallback(mPreviewCallback); 
     mCamera.startPreview(); 
     mCamera.autoFocus(mAutoFocusCallback); 
    } 
} 

}

Bitte mir helfen, das Szenario der Kamera Vorschau Größe zu bekommen.

Answer 1

Ich habe dieses Problem gelöst durch folgenden Code aus Camerapreview Klasse entfernen

if (mPreviewSize != null) { 
     previewWidth = mPreviewSize.width; 
     previewHeight = mPreviewSize.height; 
    } 

es für mich gearbeitet. Es wird Ihnen Vollbildkamera geben. Danke.

Answer 2

Ich bekomme eine kleine Oberfläche auf dem Gerät. Eigentlich möchte ich die volle Bildschirmkameravorschau den QR-Code

• scannen Wenn Sie die Kamera sagen, nicht den gesamten Bildschirm einnimmt dann versuchen, die

  zu ändern

  android:layout_width="match_parent" 
  android:layout_height="match_parent" 
  

von SurfaceView und parent_layout

• Wenn es um den Scan-Bereich ist, dass Sie in vollem Umfang nutzen zu wollen, hier geht es:

  mScannerView = new ZBarScannerView(this) { 
       /** 
       * this will alter the scanning area 
       **/ 
       @Override 
       protected IViewFinder createViewFinderView(Context context) { 
        return new CustomViewFinderView(context); 
       } 
      }; 
  
  
  
  private class CustomViewFinderView extends ViewFinderView { 
      Context context; 
  
      public CustomViewFinderView(Context context) { 
       super(context); 
       this.context = context; 
       setLaserEnabled(true); 
      } 
  
      @Override 
      public void onDraw(Canvas canvas) { 
       super.onDraw(canvas); 
       if (getFramingRect() != null) { 
        updateFrameRect(); 
        setBorderColor(ContextCompat.getColor(context, R.color.colorPrimary)); 
       } 
      } 
  
      private void updateFrameRect() { 
       Point viewResolution = new Point(this.getWidth(), this.getHeight()); 
       int height = (int) ((float) this.getHeight()); 
       int width = (int) ((float) this.getWidth()); 
  
       int leftOffset = (viewResolution.x - width)/2; 
       int topOffset = (viewResolution.y - height)/2; 
  
       getFramingRect().left = leftOffset; 
       getFramingRect().top = topOffset; 
       getFramingRect().right = leftOffset + width; 
       getFramingRect().bottom = topOffset + height; 
      } 
  } 
  

Ergebnis: