Home | History | Annotate | Download | only in app 
      1 /*
      2  * Copyright (C) 2006 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.app;
     18 
     19 import android.os.Bundle;
     20 import android.view.View;
     21 import android.widget.TabHost;
     22 import android.widget.TabWidget;
     23 import android.widget.TextView;
     24 
     25 /**
     26  * <p>For apps developing against {@link android.os.Build.VERSION_CODES#HONEYCOMB}
     27  * or later, tabs are typically presented in the UI using the new
     28  * {@link ActionBar#newTab() ActionBar.newTab()} and
     29  * related APIs for placing tabs within their action bar area.</p>
     30  *
     31  * <p>A replacement for TabActivity can also be implemented by directly using
     32  * TabHost.  You will need to define a layout that correctly uses a TabHost
     33  * with a TabWidget as well as an area in which to display your tab content.
     34  * A typical example would be:</p>
     35  *
     36  * {@sample development/samples/Support4Demos/res/layout/fragment_tabs.xml complete}
     37  *
     38  * <p>The implementation needs to take over responsibility for switching
     39  * the shown content when the user switches between tabs.
     40  *
     41  * {@sample development/samples/Support4Demos/src/com/example/android/supportv4/app/FragmentTabs.java
     42  *      complete}
     43  *
     44  * <p>Also see the <a href="{@docRoot}resources/samples/Support4Demos/src/com/example/android/supportv4/app/FragmentTabsPager.html">
     45  * Fragment Tabs Pager</a> sample for an example of using the support library's ViewPager to
     46  * allow the user to swipe the content to switch between tabs.</p>
     47  *
     48  * @deprecated New applications should use Fragments instead of this class;
     49  * to continue to run on older devices, you can use the v4 support library
     50  * which provides a version of the Fragment API that is compatible down to
     51  * {@link android.os.Build.VERSION_CODES#DONUT}.
     52  */
     53 @Deprecated
     54 public class TabActivity extends ActivityGroup {
     55     private TabHost mTabHost;
     56     private String mDefaultTab = null;
     57     private int mDefaultTabIndex = -1;
     58 
     59     public TabActivity() {
     60     }
     61 
     62     /**
     63      * Sets the default tab that is the first tab highlighted.
     64      *
     65      * @param tag the name of the default tab
     66      */
     67     public void setDefaultTab(String tag) {
     68         mDefaultTab = tag;
     69         mDefaultTabIndex = -1;
     70     }
     71 
     72     /**
     73      * Sets the default tab that is the first tab highlighted.
     74      *
     75      * @param index the index of the default tab
     76      */
     77     public void setDefaultTab(int index) {
     78         mDefaultTab = null;
     79         mDefaultTabIndex = index;
     80     }
     81 
     82     @Override
     83     protected void onRestoreInstanceState(Bundle state) {
     84         super.onRestoreInstanceState(state);
     85         ensureTabHost();
     86         String cur = state.getString("currentTab");
     87         if (cur != null) {
     88             mTabHost.setCurrentTabByTag(cur);
     89         }
     90         if (mTabHost.getCurrentTab() < 0) {
     91             if (mDefaultTab != null) {
     92                 mTabHost.setCurrentTabByTag(mDefaultTab);
     93             } else if (mDefaultTabIndex >= 0) {
     94                 mTabHost.setCurrentTab(mDefaultTabIndex);
     95             }
     96         }
     97     }
     98 
     99     @Override
    100     protected void onPostCreate(Bundle icicle) {
    101         super.onPostCreate(icicle);
    102 
    103         ensureTabHost();
    104 
    105         if (mTabHost.getCurrentTab() == -1) {
    106             mTabHost.setCurrentTab(0);
    107         }
    108     }
    109 
    110     @Override
    111     protected void onSaveInstanceState(Bundle outState) {
    112         super.onSaveInstanceState(outState);
    113         String currentTabTag = mTabHost.getCurrentTabTag();
    114         if (currentTabTag != null) {
    115             outState.putString("currentTab", currentTabTag);
    116         }
    117     }
    118 
    119     /**
    120      * Updates the screen state (current list and other views) when the
    121      * content changes.
    122      *
    123      *@see Activity#onContentChanged()
    124      */
    125     @Override
    126     public void onContentChanged() {
    127         super.onContentChanged();
    128         mTabHost = (TabHost) findViewById(com.android.internal.R.id.tabhost);
    129 
    130         if (mTabHost == null) {
    131             throw new RuntimeException(
    132                     "Your content must have a TabHost whose id attribute is " +
    133                     "'android.R.id.tabhost'");
    134         }
    135         mTabHost.setup(getLocalActivityManager());
    136     }
    137 
    138     private void ensureTabHost() {
    139         if (mTabHost == null) {
    140             this.setContentView(com.android.internal.R.layout.tab_content);
    141         }
    142     }
    143 
    144     @Override
    145     protected void
    146     onChildTitleChanged(Activity childActivity, CharSequence title) {
    147         // Dorky implementation until we can have multiple activities running.
    148         if (getLocalActivityManager().getCurrentActivity() == childActivity) {
    149             View tabView = mTabHost.getCurrentTabView();
    150             if (tabView != null && tabView instanceof TextView) {
    151                 ((TextView) tabView).setText(title);
    152             }
    153         }
    154     }
    155 
    156     /**
    157      * Returns the {@link TabHost} the activity is using to host its tabs.
    158      *
    159      * @return the {@link TabHost} the activity is using to host its tabs.
    160      */
    161     public TabHost getTabHost() {
    162         ensureTabHost();
    163         return mTabHost;
    164     }
    165 
    166     /**
    167      * Returns the {@link TabWidget} the activity is using to draw the actual tabs.
    168      *
    169      * @return the {@link TabWidget} the activity is using to draw the actual tabs.
    170      */
    171     public TabWidget getTabWidget() {
    172         return mTabHost.getTabWidget();
    173     }
    174 }
    175