maintain fragment instance state

Author: mmin18

FragmentDeveloper/res/layout/sample_fragment.xml

@@ -15,4 +15,10 @@
         android:layout_height="wrap_content"
         android:src="@drawable/bucket_icon_icloud" />
 
+    <Button
+        android:id="@+id/btn"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="0" />
+    
 </LinearLayout>

FragmentDeveloper/src/com/dianping/example/fragment/SampleFragment.java

@@ -5,13 +5,41 @@
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.Button;
 
 import com.dianping.example.fragmentdeveloper.R;
 
 public class SampleFragment extends Fragment {
+	Button btn;
+	int counter;
+
 	@Override
 	public View onCreateView(LayoutInflater inflater, ViewGroup container,
 			Bundle savedInstanceState) {
-		return inflater.inflate(R.layout.sample_fragment, container, false);
+		View v = inflater.inflate(R.layout.sample_fragment, container, false);
+		btn = (Button) v.findViewById(R.id.btn);
+		btn.setOnClickListener(new View.OnClickListener() {
+			public void onClick(View v) {
+				btn.setText(String.valueOf(++counter));
+			}
+		});
+		if (savedInstanceState != null) {
+			counter = savedInstanceState.getInt("counter");
+		}
+
+		btn.setText(String.valueOf(counter));
+		return v;
+	}
+
+	@Override
+	public void onViewCreated(View view, Bundle savedInstanceState) {
+		super.onViewCreated(view, savedInstanceState);
+
+	}
+
+	@Override
+	public void onSaveInstanceState(Bundle outState) {
+		super.onSaveInstanceState(outState);
+		outState.putInt("counter", counter);
 	}
 }

FragmentDeveloper/src/com/dianping/example/fragmentdeveloper/FragmentDeveloper.java

@@ -22,10 +22,12 @@ protected void onCreate(Bundle savedInstanceState) {
 		rootView.setId(android.R.id.primary);
 		setContentView(rootView);
 
-		Fragment f = new SampleFragment();
-		FragmentManager fm = getFragmentManager();
-		FragmentTransaction ft = fm.beginTransaction();
-		ft.add(android.R.id.primary, f);
-		ft.commit();
+		if (savedInstanceState == null) {
+			Fragment f = new SampleFragment();
+			FragmentManager fm = getFragmentManager();
+			FragmentTransaction ft = fm.beginTransaction();
+			ft.add(android.R.id.primary, f);
+			ft.commit();
+		}
 	}
 }

FragmentLoader/assets/apks/FragmentDeveloper_2.apk

@@ -83,6 +83,9 @@ protected void onCreate(Bundle savedInstanceState) {
 		rootView.setId(android.R.id.primary);
 		setContentView(rootView);
 
+		if (savedInstanceState != null)
+			return;
+
 		if ("com.dianping.intent.action.LOAD_FRAGMENT".equals(getIntent()
 				.getAction())) {
 			try {