Customize Camera View for Android using zbar

Question

I am new in android development. My app should activate the camera to scan a QR code and decode it to a string. This works fine, but I have one more requirement: to present

Answer 1

I faced the same problem. The solution is simply add the CameraPrevie in your xml inside a frameLayout, and just after that the image you want to put on top of is.

eg.:

 <FrameLayout
    android:id="@+id/captionFrame"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:layout_marginBottom="20dp"
    android:layout_marginTop="50dp" >

    <FrameLayout
        android:id="@+id/cameraPreview"
        android:layout_width="300dp"
        android:layout_height="200dp"
        android:layout_gravity="center"
        android:paddingLeft="-5dp" >

    </FrameLayout>

    <ImageView
        android:id="@+id/watermark"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="right|bottom"
        android:src="@drawable/watermark" />

</FrameLayout>

and populate it from your activity:

Camera mCamera = getCameraInstance();

ImageScanner scanner = new ImageScanner();
scanner.setConfig(0, Config.X_DENSITY, 3);
scanner.setConfig(0, Config.Y_DENSITY, 3);

CameraPreview mPreview = new CameraPreview(this, mCamera, null, autoFocusCallB);
FrameLayout preview = (FrameLayout)findViewById(R.id.cameraPreview);
 preview.addView(mPreview);

Answer 2

I think it's easier then you thought:

In the example code provided by the ZBar guy there are those two lines in the onCreate() method:

FrameLayout preview = (FrameLayout) findViewById(R.id.cameraPreview);
preview.addView(mPreview);

which are responsible for adding the "preview view" to the camerPreview Layout.

Find the mentioned lines in your code, create a new ImageView and also add it to the preview-Layout like this:

ImageView v = new ImageView(this);
v.setImageResource(R.drawable.icon);
preview.addView(v);

Adjust the size and the position of your view v and you are done!

Answer 3

To present a frame in cameraview, add an imageview in the framelayout(camerapreview) in main.xml .

   <FrameLayout
     android:id="@+id/cameraPreview"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:layout_weight="1" >
     <ImageView
        android:id="@+id/imageView1"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:alpha="0.6"
        android:src="@drawable/overlay" />
   </FrameLayout>

Use this code to make the frame(imageview) visible. As the frame(imageview) is already present in the framelayout in main.xml we need to remove it first.

    FrameLayout preview = (FrameLayout)findViewById(R.id.cameraPreview);
    ImageView iv=(ImageView) findViewById(R.id.imageView1);
    preview.addView(mPreview);
    preview.removeView(iv);
    preview.addView(iv);

To scan the camerapreview only from your frame you need to use setCrop().Adjust the size of camerapreview according to the frame.

    barcode.setData(data);
  //this is in portrait mode
  //barcode.setCrop(left,top,width,height). 
    barcode.setCrop(100,230,600,10);

This worked for me and hope it will solve your problem too. Please excuse me for my grammatical mistakes. Thank you.