SlidingTabsBasic / src / com.example.android.slidingtabsbasic /

SlidingTabsBasicFragment.java

1
/*
2
 * Copyright (C) 2013 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.slidingtabsbasic;
18
 
19
import com.example.android.common.logger.Log;
20
import com.example.android.common.view.SlidingTabLayout;
21
 
22
import android.os.Bundle;
23
import android.support.v4.app.Fragment;
24
import android.support.v4.view.PagerAdapter;
25
import android.support.v4.view.ViewPager;
26
import android.view.LayoutInflater;
27
import android.view.View;
28
import android.view.ViewGroup;
29
import android.widget.TextView;
30
 
31
/**
32
 * A basic sample which shows how to use {@link com.example.android.common.view.SlidingTabLayout}
33
 * to display a custom {@link ViewPager} title strip which gives continuous feedback to the user
34
 * when scrolling.
35
 */
36
public class SlidingTabsBasicFragment extends Fragment {
37
 
38
    static final String LOG_TAG = "SlidingTabsBasicFragment";
39
 
40
    /**
41
     * A custom {@link ViewPager} title strip which looks much like Tabs present in Android v4.0 and
42
     * above, but is designed to give continuous feedback to the user when scrolling.
43
     */
44
    private SlidingTabLayout mSlidingTabLayout;
45
 
46
    /**
47
     * A {@link ViewPager} which will be used in conjunction with the {@link SlidingTabLayout} above.
48
     */
49
    private ViewPager mViewPager;
50
 
51
    /**
52
     * Inflates the {@link View} which will be displayed by this {@link Fragment}, from the app's
53
     * resources.
54
     */
55
    @Override
56
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
57
            Bundle savedInstanceState) {
58
        return inflater.inflate(R.layout.fragment_sample, container, false);
59
    }
60
 
62
    /**
63
     * This is called after the {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} has finished.
64
     * Here we can pick out the {@link View}s we need to configure from the content view.
65
     *
66
     * We set the {@link ViewPager}'s adapter to be an instance of {@link SamplePagerAdapter}. The
67
     * {@link SlidingTabLayout} is then given the {@link ViewPager} so that it can populate itself.
68
     *
69
     * @param view View created in {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}
70
     */
71
    @Override
72
    public void onViewCreated(View view, Bundle savedInstanceState) {
74
        // Get the ViewPager and set it's PagerAdapter so that it can display items
75
        mViewPager = (ViewPager) view.findViewById(R.id.viewpager);
76
        mViewPager.setAdapter(new SamplePagerAdapter());
78
 
80
        // Give the SlidingTabLayout the ViewPager, this must be done AFTER the ViewPager has had
81
        // it's PagerAdapter set.
82
        mSlidingTabLayout = (SlidingTabLayout) view.findViewById(R.id.sliding_tabs);
83
        mSlidingTabLayout.setViewPager(mViewPager);
85
    }
87
 
88
    /**
89
     * The {@link android.support.v4.view.PagerAdapter} used to display pages in this sample.
90
     * The individual pages are simple and just display two lines of text. The important section of
91
     * this class is the {@link #getPageTitle(int)} method which controls what is displayed in the
92
     * {@link SlidingTabLayout}.
93
     */
94
    class SamplePagerAdapter extends PagerAdapter {
95
 
96
        /**
97
         * @return the number of pages to display
98
         */
99
        @Override
100
        public int getCount() {
101
            return 10;
102
        }
103
 
104
        /**
105
         * @return true if the value returned from {@link #instantiateItem(ViewGroup, int)} is the
106
         * same object as the {@link View} added to the {@link ViewPager}.
107
         */
108
        @Override
109
        public boolean isViewFromObject(View view, Object o) {
110
            return o == view;
111
        }
112
 
114
        /**
115
         * Return the title of the item at {@code position}. This is important as what this method
116
         * returns is what is displayed in the {@link SlidingTabLayout}.
117
         * <p>
118
         * Here we construct one using the position value, but for real application the title should
119
         * refer to the item's contents.
120
         */
121
        @Override
122
        public CharSequence getPageTitle(int position) {
123
            return "Item " + (position + 1);
124
        }
126
 
127
        /**
128
         * Instantiate the {@link View} which should be displayed at {@code position}. Here we
129
         * inflate a layout from the apps resources and then change the text view to signify the position.
130
         */
131
        @Override
132
        public Object instantiateItem(ViewGroup container, int position) {
133
            // Inflate a new layout from our resources
134
            View view = getActivity().getLayoutInflater().inflate(R.layout.pager_item,
135
                    container, false);
136
            // Add the newly created View to the ViewPager
137
            container.addView(view);
138
 
139
            // Retrieve a TextView from the inflated View, and update it's text
140
            TextView title = (TextView) view.findViewById(R.id.item_title);
141
            title.setText(String.valueOf(position + 1));
142
 
143
            Log.i(LOG_TAG, "instantiateItem() [position: " + position + "]");
144
 
145
            // Return the View
146
            return view;
147
        }
148
 
149
        /**
150
         * Destroy the item from the {@link ViewPager}. In our case this is simply removing the
151
         * {@link View}.
152
         */
153
        @Override
154
        public void destroyItem(ViewGroup container, int position, Object object) {
155
            container.removeView((View) object);
156
            Log.i(LOG_TAG, "destroyItem() [position: " + position + "]");
157
        }
158
 
159
    }
160
}