Create war file in grails

The war command will create a Web Application Archive (WAR) file which can be deployed on any Java EE compliant application server

grails war
grails test war
grails -Dgrails.env=foo war

Usage: 

grails [environment]* war [arguments]*

Arguments:

• nojars - Packages the WAR with no jar files. Used for shared deployment

Fired Events:

• StatusFinal - When the WAR file has been created

The war command will create a web application archive (WAR) file using the application name and version number. By default a war file deployable to the production environment will be created, but the environment can be specified using Grails standard convention

grails test war
grails dev war
grails prod war
grails war /foo/bar/mywar.war
grails war --nojars

Always better to call

grails clean

The clean command will delete all compiled resources from the current Grails application. Since Groovy is a compiled language, as with Java, this is sometimes useful to clear old instances of classes out and ensure correct compilation

Refer war

Using Fragment of Android Compatibility Package

The Android 3.0 introduce a awesome feature Fragment.
It really helpful when we design for tablet. You can refer The Android 3.0 Fragment API   for more details
Here I'm going to explain how to use Fragment for lower version.
Now android had released a static library that exposes the same Fragments API, so that applications compatible with Android 1.6 or later can use fragments to create tablet-compatible user interfaces.

For this you need to do follow these steps

• Add android-support-v4.jar to you project
• You can found this jar at yoursdkpath/extras/android/compatibility/v4/
• Copy this into your libs folder in the root of your project 
• add this jar to your project build path
• In order to use this you need to use FragmentActivity instead of Activity 

• public class Home extends FragmentActivity

• To get FragmentManager 
• Need to use getSupportFragmentManager instead of getFragmentManage

The complete code will look like this

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
public class Home extends FragmentActivity{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
  Fragment productDetails = new MyFragment();
  fragmentTransaction.replace(R.id.mainFragement, productDetails);
  fragmentTransaction.commit();
    }
}

MyFragment.java

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class MyFragment extends Fragment{
 public MyFragment(){
  Log.i("MYEXPENSETRACKER","MyFragment ()");
 }
 @Override
 public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  TextView t = new TextView(getActivity());
  t.setText("From Fragement");
  return t;
 }
}

The main.xml I used

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
    
 <FrameLayout
  android:id="@+id/mainFragement"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content">
 </FrameLayout>
</LinearLayout>

Hope it helped you..:)

Go back to previous activity

Its every common query how to go back to previous activity.
Most of us will finish activity or keep track of the activity stack and all.
But no need of this type of complex logic if you need just the same effect of user's back key press
You can use the android onBackPressed() method explicitly .

super.onBackPressed();

The default implementation simply finishes the current activity, but you can override this to do whatever you want.
The android implicitly call this method when the activity has detected the user's press of the back key.
So calling this explicitly will give the same effect