Smitha Smitha - 6 months ago 37
Android Question

Getting Camera error in Zxing Barcode Application

I am trying to use Zxing Library for developing a barcode scanner.

My activity is as follows:

public class Scanner extends Activity {

private static final String PACKAGE = "com.test.scan";
private static final String SCANNER = "com.google.zxing.client.android.SCAN";
private static final String SCAN_FORMATS = "UPC_A,UPC_E,EAN_8,EAN_13,CODE_39,CODE_93,CODE_128";
private static final String SCAN_MODE = "QR_CODE_MODE";
public static final int REQUEST_CODE = 1;

@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);

setContentView(R.layout.main);

Button ok;
ok = (Button) findViewById(R.id.b1);
ok.setOnClickListener(new View.OnClickListener() {

public void onClick(View v) {

Intent scanIntent = new Intent(SCANNER);
scanIntent.setPackage(PACKAGE);
scanIntent.addCategory(Intent.CATEGORY_DEFAULT);
scanIntent.putExtra("SCAN_FORMATS", SCAN_FORMATS);
scanIntent.putExtra("SCAN_MODE", SCAN_MODE);
try {
startActivityForResult(scanIntent, REQUEST_CODE);
} catch (ActivityNotFoundException e) {
// TODO: Exception handling
}
}

});
}


Also manifest file:

<activity android:name=".Scanner"
android:screenOrientation="landscape" android:configChanges="orientation|keyboardHidden"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
android:windowSoftInputMode="stateAlwaysHidden">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

</activity>

<activity android:name="com.google.zxing.client.android.CaptureActivity"
android:screenOrientation="landscape" android:configChanges="orientation|keyboardHidden"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
android:windowSoftInputMode="stateAlwaysHidden">
<intent-filter>
<action android:name="com.google.zxing.client.android.SCAN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity android:name="com.google.zxing.client.android.PreferencesActivity"
android:label="@string/preferences_name">
</activity>
<activity android:name="com.google.zxing.client.android.HelpActivity"
android:screenOrientation="user">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity android:name="com.google.zxing.client.android.share.ShareActivity"
android:label="@string/share_name" android:screenOrientation="user"
android:theme="@android:style/Theme.Light">
<intent-filter>
<action android:name="com.google.zxing.client.android.SHARE" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<uses-permission android:name="android.permission.CAMERA"


But I am getting the following error:

"Sorry, the Android camera encountered a problem. You may need to restart the device".

I have followed few blogs.

Log:

Unexpected error initializating camera
01-27 10:40:48.281: WARN/CaptureActivity(1007): java.lang.RuntimeException: Fail to connect to camera service
01-27 10:40:48.281: WARN/CaptureActivity(1007): at android.hardware.Camera.native_setup(Native Method)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at android.hardware.Camera.<init>(Camera.java:185)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at android.hardware.Camera.open(Camera.java:165)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at com.google.zxing.client.android.camera.CameraManager.openDriver(CameraManager.java:126)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at com.google.zxing.client.android.CaptureActivity.initCamera(CaptureActivity.java:606)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at com.google.zxing.client.android.CaptureActivity.surfaceCreated(CaptureActivity.java:346)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at android.view.SurfaceView.updateWindow(SurfaceView.java:532)
01-27 10:40:48.281: WARN/CaptureActivity(1007): at android.view.SurfaceView.dispatchDraw(SurfaceView.java:339)


Thanks

Sneha

Answer

This means the device returned null from Camera.open() and it shouldn't ever do that. It's treated as a device bug. I am not sure how you would debug why it is doing this, but that's the cause.

The only time I have seen this happen consistently is on Android 2.2 devices that have a front camera, only. The API for accessing a front camera only appeared in Android 2.3, and the previous Camera.open() API method may only return a rear-facing camera. So these return null. And it is a device bug, really, since they really need to be running Android 2.3 to let apps use a front camera.