1 /*
2  * Copyright 2012 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 com.example.android.tabcompat.lib;
18 
19 import android.os.Build;
20 import android.os.Bundle;
21 import android.support.v4.app.FragmentActivity;
22 
23 /**
24  * Convenience helper to build a set of tabs for a {@link TabCompatActivity}. To use this class,
25  * extend {@link TabCompatActivity} and:
26  *
27  * Call {@link TabCompatActivity#getTabHelper()}, returning a {@link TabHelper}.
28  *
29  * Create a {@link CompatTabListener}.
30  *
31  * Call {@link TabHelper#newTab(String)} to create each tab.
32  *
33  * Call CompatTab.setText().setIcon().setTabListener() to set up your tabs.
34  *
35  * Call {@link TabHelper#addTab(CompatTab)} for each tab, and you're done.
36  */
37 public abstract class TabHelper {
38 
39     protected FragmentActivity mActivity;
40 
TabHelper(FragmentActivity activity)41     protected TabHelper(FragmentActivity activity) {
42         mActivity = activity;
43     }
44 
45     /**
46      * Factory method for creating TabHelper objects for a given activity. Depending on which device
47      * the app is running, either a basic helper or Honeycomb-specific helper will be returned.
48      * Don't call this yourself; the TabCompatActivity instantiates one. Instead call
49      * TabCompatActivity.getTabHelper().
50      */
createInstance(FragmentActivity activity)51     public static TabHelper createInstance(FragmentActivity activity) {
52         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
53             return new TabHelperHoneycomb(activity);
54         } else {
55             return new TabHelperEclair(activity);
56         }
57     }
58 
59     /**
60      * Create a new tab.
61      *
62      * @param tag A unique tag to associate with the tab and associated fragment
63      * @return CompatTab for the appropriate android version
64      */
newTab(String tag)65     public CompatTab newTab(String tag) {
66         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
67             return new CompatTabHoneycomb(mActivity, tag);
68         } else {
69             return new CompatTabEclair(mActivity, tag);
70         }
71     }
72 
addTab(CompatTab tab)73     public abstract void addTab(CompatTab tab);
74 
onSaveInstanceState(Bundle outState)75     protected abstract void onSaveInstanceState(Bundle outState);
76 
onRestoreInstanceState(Bundle savedInstanceState)77     protected abstract void onRestoreInstanceState(Bundle savedInstanceState);
78 
setUp()79     protected abstract void setUp();
80 }
81