API demo for nesting fragments.

Change-Id: I7f20e4f00cf68c78c578ae620a95de7fa97f0761

4 files changed, 506 insertions, 2 deletions

diff --git a/samples/Support13Demos/src/com/example/android/supportv13/app/CountingFragment.java b/samples/Support13Demos/src/com/example/android/supportv13/app/CountingFragment.java
index 8672ed22a..d52955b21 100644
--- a/samples/Support13Demos/src/com/example/android/supportv13/app/CountingFragment.java
+++ b/samples/Support13Demos/src/com/example/android/supportv13/app/CountingFragment.java
@@ -58,10 +58,9 @@ public class CountingFragment extends Fragment {
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
             Bundle savedInstanceState) {
-        View v = inflater.inflate(R.layout.hello_world, container, false);
+        View v = inflater.inflate(R.layout.counting, 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;
     }
 }
diff --git a/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java
new file mode 100644
index 000000000..0a88a0507
--- /dev/null
+++ b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2012 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.supportv13.app;
+
+import java.util.ArrayList;
+
+import com.example.android.supportv13.R;
+
+import android.app.ActionBar;
+import android.app.ActionBar.Tab;
+import android.app.Activity;
+import android.app.Fragment;
+import android.app.FragmentTransaction;
+import android.content.Context;
+import android.os.Bundle;
+import android.support.v13.app.FragmentPagerAdapter;
+import android.support.v4.view.ViewPager;
+
+//BEGIN_INCLUDE(complete)
+public class FragmentNestingPagerSupport extends Activity {
+    ViewPager mViewPager;
+    TabsAdapter mTabsAdapter;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        mViewPager = new ViewPager(this);
+        mViewPager.setId(R.id.pager);
+        setContentView(mViewPager);
+
+        final ActionBar bar = getActionBar();
+        bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
+        bar.setDisplayOptions(0, ActionBar.DISPLAY_SHOW_TITLE);
+
+        mTabsAdapter = new TabsAdapter(this, mViewPager);
+        mTabsAdapter.addTab(bar.newTab().setText("Simple"),
+                CountingFragment.class, null);
+        mTabsAdapter.addTab(bar.newTab().setText("List"),
+                FragmentPagerSupport.ArrayListFragment.class, null);
+        mTabsAdapter.addTab(bar.newTab().setText("Cursor"),
+                CursorFragment.class, null);
+        mTabsAdapter.addTab(bar.newTab().setText("Tabs"),
+                FragmentTabsFragment.class, null);
+
+        if (savedInstanceState != null) {
+            bar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0));
+        }
+    }
+
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        outState.putInt("tab", getActionBar().getSelectedNavigationIndex());
+    }
+
+    /**
+     * This is a helper class that implements the management of tabs and all
+     * details of connecting a ViewPager with associated TabHost.  It relies on a
+     * trick.  Normally a tab host has a simple API for supplying a View or
+     * Intent that each tab will show.  This is not sufficient for switching
+     * between pages.  So instead we make the content part of the tab host
+     * 0dp high (it is not shown) and the TabsAdapter supplies its own dummy
+     * view to show as the tab content.  It listens to changes in tabs, and takes
+     * care of switch to the correct paged in the ViewPager whenever the selected
+     * tab changes.
+     */
+    public static class TabsAdapter extends FragmentPagerAdapter
+            implements ActionBar.TabListener, ViewPager.OnPageChangeListener {
+        private final Context mContext;
+        private final ActionBar mActionBar;
+        private final ViewPager mViewPager;
+        private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();
+
+        static final class TabInfo {
+            private final Class<?> clss;
+            private final Bundle args;
+
+            TabInfo(Class<?> _class, Bundle _args) {
+                clss = _class;
+                args = _args;
+            }
+        }
+
+        public TabsAdapter(Activity activity, ViewPager pager) {
+            super(activity.getFragmentManager());
+            mContext = activity;
+            mActionBar = activity.getActionBar();
+            mViewPager = pager;
+            mViewPager.setAdapter(this);
+            mViewPager.setOnPageChangeListener(this);
+        }
+
+        public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
+            TabInfo info = new TabInfo(clss, args);
+            tab.setTag(info);
+            tab.setTabListener(this);
+            mTabs.add(info);
+            mActionBar.addTab(tab);
+            notifyDataSetChanged();
+        }
+
+        @Override
+        public int getCount() {
+            return mTabs.size();
+        }
+
+        @Override
+        public Fragment getItem(int position) {
+            TabInfo info = mTabs.get(position);
+            return Fragment.instantiate(mContext, info.clss.getName(), info.args);
+        }
+
+        @Override
+        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
+        }
+
+        @Override
+        public void onPageSelected(int position) {
+            mActionBar.setSelectedNavigationItem(position);
+        }
+
+        @Override
+        public void onPageScrollStateChanged(int state) {
+        }
+
+        @Override
+        public void onTabSelected(Tab tab, FragmentTransaction ft) {
+            Object tag = tab.getTag();
+            for (int i=0; i<mTabs.size(); i++) {
+                if (mTabs.get(i) == tag) {
+                    mViewPager.setCurrentItem(i);
+                }
+            }
+        }
+
+        @Override
+        public void onTabUnselected(Tab tab, FragmentTransaction ft) {
+        }
+
+        @Override
+        public void onTabReselected(Tab tab, FragmentTransaction ft) {
+        }
+    }
+}
+//END_INCLUDE(complete)
diff --git a/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingStatePagerSupport.java b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingStatePagerSupport.java
new file mode 100644
index 000000000..58638528b
--- /dev/null
+++ b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingStatePagerSupport.java
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2012 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.supportv13.app;
+
+import java.util.ArrayList;
+
+import com.example.android.supportv13.R;
+
+import android.app.ActionBar;
+import android.app.ActionBar.Tab;
+import android.app.Activity;
+import android.app.Fragment;
+import android.app.FragmentTransaction;
+import android.content.Context;
+import android.os.Bundle;
+import android.support.v13.app.FragmentStatePagerAdapter;
+import android.support.v4.view.ViewPager;
+
+//BEGIN_INCLUDE(complete)
+public class FragmentNestingStatePagerSupport extends Activity {
+    ViewPager mViewPager;
+    TabsAdapter mTabsAdapter;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        mViewPager = new ViewPager(this);
+        mViewPager.setId(R.id.pager);
+        setContentView(mViewPager);
+
+        final ActionBar bar = getActionBar();
+        bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
+        bar.setDisplayOptions(0, ActionBar.DISPLAY_SHOW_TITLE);
+
+        mTabsAdapter = new TabsAdapter(this, mViewPager);
+        mTabsAdapter.addTab(bar.newTab().setText("Simple"),
+                CountingFragment.class, null);
+        mTabsAdapter.addTab(bar.newTab().setText("List"),
+                FragmentPagerSupport.ArrayListFragment.class, null);
+        mTabsAdapter.addTab(bar.newTab().setText("Cursor"),
+                CursorFragment.class, null);
+        mTabsAdapter.addTab(bar.newTab().setText("Tabs"),
+                FragmentTabsFragment.class, null);
+
+        if (savedInstanceState != null) {
+            bar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0));
+        }
+    }
+
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        outState.putInt("tab", getActionBar().getSelectedNavigationIndex());
+    }
+
+    /**
+     * This is a helper class that implements the management of tabs and all
+     * details of connecting a ViewPager with associated TabHost.  It relies on a
+     * trick.  Normally a tab host has a simple API for supplying a View or
+     * Intent that each tab will show.  This is not sufficient for switching
+     * between pages.  So instead we make the content part of the tab host
+     * 0dp high (it is not shown) and the TabsAdapter supplies its own dummy
+     * view to show as the tab content.  It listens to changes in tabs, and takes
+     * care of switch to the correct paged in the ViewPager whenever the selected
+     * tab changes.
+     */
+    public static class TabsAdapter extends FragmentStatePagerAdapter
+            implements ActionBar.TabListener, ViewPager.OnPageChangeListener {
+        private final Context mContext;
+        private final ActionBar mActionBar;
+        private final ViewPager mViewPager;
+        private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();
+
+        static final class TabInfo {
+            private final Class<?> clss;
+            private final Bundle args;
+
+            TabInfo(Class<?> _class, Bundle _args) {
+                clss = _class;
+                args = _args;
+            }
+        }
+
+        public TabsAdapter(Activity activity, ViewPager pager) {
+            super(activity.getFragmentManager());
+            mContext = activity;
+            mActionBar = activity.getActionBar();
+            mViewPager = pager;
+            mViewPager.setAdapter(this);
+            mViewPager.setOnPageChangeListener(this);
+        }
+
+        public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
+            TabInfo info = new TabInfo(clss, args);
+            tab.setTag(info);
+            tab.setTabListener(this);
+            mTabs.add(info);
+            mActionBar.addTab(tab);
+            notifyDataSetChanged();
+        }
+
+        @Override
+        public int getCount() {
+            return mTabs.size();
+        }
+
+        @Override
+        public Fragment getItem(int position) {
+            TabInfo info = mTabs.get(position);
+            return Fragment.instantiate(mContext, info.clss.getName(), info.args);
+        }
+
+        @Override
+        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
+        }
+
+        @Override
+        public void onPageSelected(int position) {
+            mActionBar.setSelectedNavigationItem(position);
+        }
+
+        @Override
+        public void onPageScrollStateChanged(int state) {
+        }
+
+        @Override
+        public void onTabSelected(Tab tab, FragmentTransaction ft) {
+            Object tag = tab.getTag();
+            for (int i=0; i<mTabs.size(); i++) {
+                if (mTabs.get(i) == tag) {
+                    mViewPager.setCurrentItem(i);
+                }
+            }
+        }
+
+        @Override
+        public void onTabUnselected(Tab tab, FragmentTransaction ft) {
+        }
+
+        @Override
+        public void onTabReselected(Tab tab, FragmentTransaction ft) {
+        }
+    }
+}
+//END_INCLUDE(complete)
diff --git a/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentTabsFragment.java b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentTabsFragment.java
new file mode 100644
index 000000000..fbc464dda
--- /dev/null
+++ b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentTabsFragment.java
@@ -0,0 +1,187 @@
+/*
+ * Copyright (C) 2012 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.supportv13.app;
+
+import java.util.HashMap;
+
+import com.example.android.supportv13.R;
+
+import android.app.Fragment;
+import android.app.FragmentManager;
+import android.app.FragmentTransaction;
+import android.content.Context;
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TabHost;
+
+public class FragmentTabsFragment extends Fragment {
+    TabHost mTabHost;
+    TabManager mTabManager;
+    String mCurrentTabTag;
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+            Bundle savedInstanceState) {
+        View v = inflater.inflate(R.layout.fragment_tabs_fragment, container, false);
+        mTabHost = (TabHost)v.findViewById(android.R.id.tabhost);
+        mTabHost.setup();
+
+        mTabManager = new TabManager(getActivity(), getChildFragmentManager(),
+                mTabHost, R.id.realtabcontent);
+
+        mTabManager.addTab(mTabHost.newTabSpec("simple").setIndicator("Simple"),
+                CountingFragment.class, null);
+        mTabManager.addTab(mTabHost.newTabSpec("array").setIndicator("Array"),
+                FragmentPagerSupport.ArrayListFragment.class, null);
+        mTabManager.addTab(mTabHost.newTabSpec("cursor").setIndicator("Cursor"),
+                CursorFragment.class, null);
+
+        return v;
+    }
+
+    @Override
+    public void onViewStateRestored(Bundle savedInstanceState) {
+        super.onViewStateRestored(savedInstanceState);
+        if (savedInstanceState != null) {
+            mCurrentTabTag = savedInstanceState.getString("tab");
+        }
+        mTabHost.setCurrentTabByTag(mCurrentTabTag);
+    }
+
+    @Override
+    public void onDestroyView() {
+        super.onDestroyView();
+        // Need to remember the selected tab so that we can restore it if
+        // we later re-create the views.
+        mCurrentTabTag = mTabHost.getCurrentTabTag();
+        mTabHost = null;
+        mTabManager = null;
+    }
+
+    @Override
+    public void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        outState.putString("tab", mTabHost != null
+                ? mTabHost.getCurrentTabTag() : mCurrentTabTag);
+    }
+
+    /**
+     * This is a helper class that implements a generic mechanism for
+     * associating fragments with the tabs in a tab host.  It relies on a
+     * trick.  Normally a tab host has a simple API for supplying a View or
+     * Intent that each tab will show.  This is not sufficient for switching
+     * between fragments.  So instead we make the content part of the tab host
+     * 0dp high (it is not shown) and the TabManager supplies its own dummy
+     * view to show as the tab content.  It listens to changes in tabs, and takes
+     * care of switch to the correct fragment shown in a separate content area
+     * whenever the selected tab changes.
+     */
+    public static class TabManager implements TabHost.OnTabChangeListener {
+        private final Context mContext;
+        private final FragmentManager mManager;
+        private final TabHost mTabHost;
+        private final int mContainerId;
+        private final HashMap<String, TabInfo> mTabs = new HashMap<String, TabInfo>();
+        TabInfo mLastTab;
+
+        static final class TabInfo {
+            private final String tag;
+            private final Class<?> clss;
+            private final Bundle args;
+            private Fragment fragment;
+
+            TabInfo(String _tag, Class<?> _class, Bundle _args) {
+                tag = _tag;
+                clss = _class;
+                args = _args;
+            }
+        }
+
+        static class DummyTabFactory implements TabHost.TabContentFactory {
+            private final Context mContext;
+
+            public DummyTabFactory(Context context) {
+                mContext = context;
+            }
+
+            @Override
+            public View createTabContent(String tag) {
+                View v = new View(mContext);
+                v.setMinimumWidth(0);
+                v.setMinimumHeight(0);
+                return v;
+            }
+        }
+
+        public TabManager(Context context, FragmentManager manager, TabHost tabHost,
+                int containerId) {
+            mContext = context;
+            mManager = manager;
+            mTabHost = tabHost;
+            mContainerId = containerId;
+            mTabHost.setOnTabChangedListener(this);
+        }
+
+        public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, Bundle args) {
+            tabSpec.setContent(new DummyTabFactory(mContext));
+            String tag = tabSpec.getTag();
+
+            TabInfo info = new TabInfo(tag, clss, args);
+
+            // Check to see if we already have a fragment for this tab, probably
+            // from a previously saved state.  If so, deactivate it, because our
+            // initial state is that a tab isn't shown.
+            info.fragment = mManager.findFragmentByTag(tag);
+            if (info.fragment != null && !info.fragment.isDetached()) {
+                FragmentTransaction ft = mManager.beginTransaction();
+                ft.detach(info.fragment);
+                ft.commit();
+            }
+
+            mTabs.put(tag, info);
+            mTabHost.addTab(tabSpec);
+        }
+
+        @Override
+        public void onTabChanged(String tabId) {
+            TabInfo newTab = mTabs.get(tabId);
+            if (mLastTab != newTab) {
+                FragmentTransaction ft = mManager.beginTransaction();
+                if (mLastTab != null) {
+                    if (mLastTab.fragment != null) {
+                        ft.detach(mLastTab.fragment);
+                    }
+                }
+                if (newTab != null) {
+                    if (newTab.fragment == null) {
+                        newTab.fragment = Fragment.instantiate(mContext,
+                                newTab.clss.getName(), newTab.args);
+                        ft.add(mContainerId, newTab.fragment, newTab.tag);
+                    } else {
+                        ft.attach(newTab.fragment);
+                    }
+                }
+
+                mLastTab = newTab;
+                ft.commit();
+                mManager.executePendingTransactions();
+            }
+        }
+    }
+}
+//END_INCLUDE(complete)