how can take picture by camera simple code android

main xml
======

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Capture Image" />

    <Button
        android:id="@+id/btCamera_main"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Take Picture" />

</LinearLayout>

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activity class Name=CameraTestAppsActivity.java
============
code :
======

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class CameraTestAppsActivity extends Activity {

Button btCamera;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        btCamera=(Button)findViewById(R.id.btCamera_main);
     
     
        btCamera.setOnClickListener(new OnClickListener()
        {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // intent.putExtra(MediaStore.EXTRA_OUTPUT,Uri.fromFile(mInterface.getTempFile()));
     startActivityForResult(intent, 0);

}
});
     
   
    }
 
    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == Activity.RESULT_OK && requestCode == 0) {
    String result = data.toURI();
    // ...
    }
    }
}

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