Life cycle of MasterDetailFlow HelloWorld

In my previous post Life cycle of Fragment experience to know Lifecycle of simple Fragment. After that, Google released Android SDK Android SDK Tools Revision 20 support template. You can create HelloWorld running in Fragment easily, using MasterDetailFlow template. It's a great tutorial for Fragment. As a beginner, I suggest all beginner try it and understand it.

It's modified to display lifecycle using the same technique.

- Create a HelloWorld of MasterDetailFlow, with Minimum Required SDK of API 11 Android 3.0 (Honeycomb) and Build SDK of Android 4.1 (API 16).

- Modify activity_item_twopane.xml to add a TextView to display the status. It's the layout on tablet.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginLeft="16dp"
    android:layout_marginRight="16dp"
    android:divider="?android:attr/dividerHorizontal"
    android:showDividers="middle"
    tools:context=".ItemListActivity">

    <LinearLayout 
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="3"
        android:orientation="vertical"
        >
        <fragment android:name="com.example.helloworld.ItemListFragment"
        android:id="@+id/item_list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
        <ScrollView 
            android:layout_width="match_parent"
            android:layout_height="match_parent">
            <TextView
                android:id="@+id/status"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:text="status"/>
            
        </ScrollView>
    </LinearLayout>
    
    <FrameLayout android:id="@+id/item_detail_container"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1" />

</LinearLayout>

- Modify ItemListActivity.java to implement updateMyStatus() and updateStatus() methods, and display lifecycle.

package com.example.helloworld;

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.NavUtils;
import android.view.MenuItem;
import android.widget.TextView;

public class ItemListActivity extends FragmentActivity
        implements ItemListFragment.Callbacks {

    private boolean mTwoPane;
    
    String myStatus = "";
    TextView status;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_item_list);

        if (findViewById(R.id.item_detail_container) != null) {
            mTwoPane = true;
            ((ItemListFragment) getSupportFragmentManager()
                    .findFragmentById(R.id.item_list))
                    .setActivateOnItemClick(true);
        }
        
        status = (TextView)findViewById(R.id.status);
        updateMyStatus("onCreate() with mTwoPane = " + String.valueOf(mTwoPane));
    }
    
    private void updateMyStatus(String myst){
     updateStatus("ItemListActivity: " + myst);
    }
    
    public void updateStatus(String st){
     if(status == null){
      myStatus += "delay - " + st + "\n"; 
     }else{
      myStatus += st + "\n";
      status.setText(myStatus); 
     }
    }

    @Override
    public void onItemSelected(String id) {
        if (mTwoPane) {
            Bundle arguments = new Bundle();
            arguments.putString(ItemDetailFragment.ARG_ITEM_ID, id);
            ItemDetailFragment fragment = new ItemDetailFragment();
            fragment.setArguments(arguments);
            getSupportFragmentManager().beginTransaction()
                    .replace(R.id.item_detail_container, fragment)
                    .commit();

        } else {
            Intent detailIntent = new Intent(this, ItemDetailActivity.class);
            detailIntent.putExtra(ItemDetailFragment.ARG_ITEM_ID, id);
            startActivity(detailIntent);
        }
        
        updateMyStatus("onItemSelected()");
    }

 @Override
 protected void onDestroy() {
  // TODO Auto-generated method stub
  super.onDestroy();
  updateMyStatus("onDestroy()");
 }

 @Override
 protected void onPause() {
  // TODO Auto-generated method stub
  super.onPause();
  updateMyStatus("onPause()");
 }

 @Override
 protected void onResume() {
  // TODO Auto-generated method stub
  super.onResume();
  updateMyStatus("onResume()");
 }

 @Override
 protected void onStart() {
  // TODO Auto-generated method stub
  super.onStart();
  updateMyStatus("onStart()");
 }

 @Override
 protected void onStop() {
  // TODO Auto-generated method stub
  super.onStop();
  updateMyStatus("onStop()");
 }
    
}

- Modify ItemDetailFragment.java

package com.example.helloworld;

import com.example.helloworld.dummy.DummyContent;

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

public class ItemDetailFragment extends Fragment {

    public static final String ARG_ITEM_ID = "item_id";

    DummyContent.DummyItem mItem;

    public ItemDetailFragment() {
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments().containsKey(ARG_ITEM_ID)) {
            mItem = DummyContent.ITEM_MAP.get(getArguments().getString(ARG_ITEM_ID));
        }
        
        updateMyStatus("onCreate()");
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_item_detail, container, false);
        if (mItem != null) {
            ((TextView) rootView.findViewById(R.id.item_detail)).setText(mItem.content);
        }
        
        updateMyStatus("onCreateView()");
        
        return rootView;
    }
    
    private void updateMyStatus(String myst){
     if(getActivity().getClass() == ItemListActivity.class){
      
      String me;
      
      if(mItem == null){
       me = "unknown";
      }else{
       me = mItem.content;
      }
      
      ((ItemListActivity)getActivity()).updateStatus(" >> ItemDetailFragment: " 
        + me + " >> "
        + myst);
     }
    }

 @Override
 public void onActivityCreated(Bundle savedInstanceState) {
  // TODO Auto-generated method stub
  super.onActivityCreated(savedInstanceState);
  updateMyStatus("onActivityCreated()");
 }

 @Override
 public void onAttach(Activity activity) {
  // TODO Auto-generated method stub
  super.onAttach(activity);
  updateMyStatus("onAttach()");
 }

 @Override
 public void onDestroy() {
  // TODO Auto-generated method stub
  super.onDestroy();
  updateMyStatus("onDestroy()");
 }

 @Override
 public void onDestroyView() {
  // TODO Auto-generated method stub
  super.onDestroyView();
  updateMyStatus("onDestroyView()");
 }

 @Override
 public void onDetach() {
  // TODO Auto-generated method stub
  super.onDetach();
  updateMyStatus("onDetach()");
 }

 @Override
 public void onPause() {
  // TODO Auto-generated method stub
  super.onPause();
  updateMyStatus("onPause()");
 }

 @Override
 public void onResume() {
  // TODO Auto-generated method stub
  super.onResume();
  updateMyStatus("onResume()");
 }

 @Override
 public void onStart() {
  // TODO Auto-generated method stub
  super.onStart();
  updateMyStatus("onStart()");
 }

 @Override
 public void onStop() {
  // TODO Auto-generated method stub
  super.onStop();
  updateMyStatus("onStop()");
 }

}

Please note that this exercise is applied on tablet version only.

Download the files.