How to connect Android device to digital camera through USB?
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I am making a demo application in which i want to communicate a canon digital camera to Android device through USB through below through Android developer site i have created a min class i have write following code not sure may be it is working or not plz help guide me how to communicate digital camera to Android device?
http://developer.android.com/guide/topics/connectivity/usb/host.html`

    import java.util.HashMap;
    
    import android.app.Activity;
    import android.content.Context;
    import android.content.Intent;
    import android.hardware.usb.UsbDevice;
    import android.hardware.usb.UsbManager;
    import android.os.Bundle;
    
    public class USBMainclass  extends Activity
    {
       
    	@Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            Intent intent =new Intent();
            UsbDevice device = (UsbDevice) intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
            UsbManager manager = (UsbManager)this.getSystemService(Context.USB_SERVICE);
            HashMap<String, UsbDevice> deviceList = manager.getDeviceList();
        }
    }

and in Android manifest file is 

    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.USBCommunication"
        android:versionCode="1"
        android:versionName="1.0" >
    
        <uses-sdk android:minSdkVersion="12" />
         
        <application
            android:icon="@drawable/ic_launcher"
            android:label="@string/app_name" >
            
            <activity android:name=".USBMainclass">
      <intent-filter>
      <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /> 
      </intent-filter>
      <meta-data android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" /> 
      </activity>
      
        </application>
    
    </manifest>

i just want to Application detect digital camera through this code plz help..