How to scan QRcode / barcode Scanner using ZBar Library In Android app?

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First Download Zbar Jar file and put on libs folder:

zbar.jar file

 

download CameraPreviewForScan.class file CameraPreviewForScan

 

main_activity.xml

<?xml version=”1.0″ encoding=”utf-8″?>
<LinearLayout xmlns:android=”http://schemas.android.com/apk/res/android”
xmlns:tools=”http://schemas.android.com/tools”
android:id=”@+id/LinearLayoutpicturedetail”
android:layout_width=”fill_parent”
android:layout_height=”match_parent”
android:orientation=”vertical” >

<LinearLayout
android:id=”@+id/scan_layout”
android:layout_width=”match_parent”
android:layout_height=”wrap_content”
android:orientation=”horizontal” >

<FrameLayout
android:id=”@+id/cameraPreview”
android:layout_width=”match_parent”
android:layout_height=”match_parent”/>
</LinearLayout>

</LinearLayout>

 

MainActivity.java

public class MainActivity extends Activity {
// Variable and Object Declaration
private Camera mCamera;
private CameraPreviewForScan mPreview;
private Handler autoFocusHandler;

private boolean barcodeScanned = false;
private boolean previewing = true;

LinearLayout scanLayout;
ImageScanner scanner;

static {
System.loadLibrary(“iconv”);
}

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

setContentView(R.layout.main_activity);

scanLayout = (LinearLayout) findViewById(R.id.scan_layout);

setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);

autoFocusHandler = new Handler();
mCamera = getCameraInstance();

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

mPreview = new CameraPreviewForScan(CameraTestActivity.this, mCamera, previewCb, autoFocusCB);
FrameLayout preview = (FrameLayout) findViewById(R.id.cameraPreview);
preview.addView(mPreview);

}

@Override
public void onBackPressed() {
// TODO Auto-generated method stub
if (barcodeScanned) {
barcodeScanned = false;
mCamera.setPreviewCallback(previewCb);
mCamera.startPreview();
previewing = true;
mCamera.autoFocus(autoFocusCB);
}
}

public void onPause() {
super.onPause();
releaseCamera();
}

/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance() {
Camera c = null;
try {
c = Camera.open();
} catch (Exception e) {}
return c;
}

private void releaseCamera() {
if (mCamera != null) {
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.release();
mCamera = null;
}
}

private Runnable doAutoFocus = new Runnable() {
public void run() {
if (previewing)
mCamera.autoFocus(autoFocusCB);
}
};

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

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

int result = scanner.scanImage(barcode);

if (result != 0) {
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.stopPreview();

SymbolSet syms = scanner.getResults();
for (Symbol sym : syms) {
Toast.makeText(CameraTestActivity.this, “barcode result ” + sym.getData(), Toast.LENGTH_SHORT).show();
barcodeScanned = true;
}
}
}
};

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