/* * Copyright (C) 2010 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.apis.app; import com.example.android.apis.R; import android.app.Activity; import android.app.Fragment; import android.app.FragmentTransaction; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; public class FragmentStack extends Activity { int mStackLevel = 1; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.fragment_stack); // Watch for button clicks. Button button = (Button)findViewById(R.id.new_fragment); button.setOnClickListener(new OnClickListener() { public void onClick(View v) { addFragmentToStack(); } }); button = (Button)findViewById(R.id.delete_fragment); button.setOnClickListener(new OnClickListener() { public void onClick(View v) { getFragmentManager().popBackStack(); } }); if (savedInstanceState == null) { // Do first time initialization -- add initial fragment. Fragment newFragment = CountingFragment.newInstance(mStackLevel); FragmentTransaction ft = getFragmentManager().beginTransaction(); ft.add(R.id.simple_fragment, newFragment).commit(); } else { mStackLevel = savedInstanceState.getInt("level"); } } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putInt("level", mStackLevel); } void addFragmentToStack() { mStackLevel++; // Instantiate a new fragment. Fragment newFragment = CountingFragment.newInstance(mStackLevel); // Add the fragment to the activity, pushing this transaction // on to the back stack. FragmentTransaction ft = getFragmentManager().beginTransaction(); ft.replace(R.id.simple_fragment, newFragment); ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); ft.addToBackStack(null); ft.commit(); } public static class CountingFragment extends Fragment { int mNum; /** * Create a new instance of CountingFragment, providing "num" * as an argument. */ static CountingFragment newInstance(int num) { CountingFragment f = new CountingFragment(); // Supply num input as an argument. Bundle args = new Bundle(); args.putInt("num", num); f.setArguments(args); return f; } /** * When creating, retrieve this instance's number from its arguments. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mNum = getArguments() != null ? getArguments().getInt("num") : 1; } /** * The Fragment's UI is just a simple text view showing its * instance number. */ @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View v = inflater.inflate(R.layout.hello_world, container, false); View tv = v.findViewById(R.id.text); ((TextView)tv).setText("Fragment #" + mNum); tv.setBackgroundDrawable(getResources().getDrawable(android.R.drawable.gallery_thumb)); return v; } } }