1 /*
2  * Copyright (C) 2014 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 package com.android.contacts.common.list;
17 
18 import android.content.Context;
19 import android.content.res.ColorStateList;
20 import android.content.res.TypedArray;
21 import android.graphics.Outline;
22 import android.support.v4.view.PagerAdapter;
23 import android.support.v4.view.ViewPager;
24 import android.util.AttributeSet;
25 import android.util.TypedValue;
26 import android.view.Gravity;
27 import android.view.LayoutInflater;
28 import android.view.View;
29 import android.view.ViewOutlineProvider;
30 import android.widget.FrameLayout;
31 import android.widget.HorizontalScrollView;
32 import android.widget.LinearLayout;
33 import android.widget.TextView;
34 import android.widget.Toast;
35 
36 import com.android.contacts.common.R;
37 import com.android.contacts.common.compat.CompatUtils;
38 
39 /**
40  * Lightweight implementation of ViewPager tabs. This looks similar to traditional actionBar tabs,
41  * but allows for the view containing the tabs to be placed anywhere on screen. Text-related
42  * attributes can also be assigned in XML - these will get propogated to the child TextViews
43  * automatically.
44  */
45 public class ViewPagerTabs extends HorizontalScrollView implements ViewPager.OnPageChangeListener {
46 
47     ViewPager mPager;
48     private ViewPagerTabStrip mTabStrip;
49 
50     /**
51      * Linearlayout that will contain the TextViews serving as tabs. This is the only child
52      * of the parent HorizontalScrollView.
53      */
54     final int mTextStyle;
55     final ColorStateList mTextColor;
56     final int mTextSize;
57     final boolean mTextAllCaps;
58     int mPrevSelected = -1;
59     int mSidePadding;
60 
61     private int[] mTabIcons;
62     // For displaying the unread count next to the tab icon.
63     private int[] mUnreadCounts;
64 
65     private static final ViewOutlineProvider VIEW_BOUNDS_OUTLINE_PROVIDER;
66     static {
67         if (CompatUtils.isLollipopCompatible()) {
68             VIEW_BOUNDS_OUTLINE_PROVIDER = new ViewOutlineProvider() {
69                 @Override
70                 public void getOutline(View view, Outline outline) {
71                     outline.setRect(0, 0, view.getWidth(), view.getHeight());
72                 }
73             };
74         } else {
75             VIEW_BOUNDS_OUTLINE_PROVIDER = null;
76         }
77     }
78 
79     private static final int TAB_SIDE_PADDING_IN_DPS = 10;
80 
81     // TODO: This should use <declare-styleable> in the future
82     private static final int[] ATTRS = new int[] {
83         android.R.attr.textSize,
84         android.R.attr.textStyle,
85         android.R.attr.textColor,
86         android.R.attr.textAllCaps
87     };
88 
89     /**
90      * Simulates actionbar tab behavior by showing a toast with the tab title when long clicked.
91      */
92     private class OnTabLongClickListener implements OnLongClickListener {
93         final int mPosition;
94 
OnTabLongClickListener(int position)95         public OnTabLongClickListener(int position) {
96             mPosition = position;
97         }
98 
99         @Override
onLongClick(View v)100         public boolean onLongClick(View v) {
101             final int[] screenPos = new int[2];
102             getLocationOnScreen(screenPos);
103 
104             final Context context = getContext();
105             final int width = getWidth();
106             final int height = getHeight();
107             final int screenWidth = context.getResources().getDisplayMetrics().widthPixels;
108 
109             Toast toast = Toast.makeText(context, mPager.getAdapter().getPageTitle(mPosition),
110                     Toast.LENGTH_SHORT);
111 
112             // Show the toast under the tab
113             toast.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL,
114                     (screenPos[0] + width / 2) - screenWidth / 2, screenPos[1] + height);
115 
116             toast.show();
117             return true;
118         }
119     }
120 
ViewPagerTabs(Context context)121     public ViewPagerTabs(Context context) {
122         this(context, null);
123     }
124 
ViewPagerTabs(Context context, AttributeSet attrs)125     public ViewPagerTabs(Context context, AttributeSet attrs) {
126         this(context, attrs, 0);
127     }
128 
ViewPagerTabs(Context context, AttributeSet attrs, int defStyle)129     public ViewPagerTabs(Context context, AttributeSet attrs, int defStyle) {
130         super(context, attrs, defStyle);
131         setFillViewport(true);
132 
133         mSidePadding = (int) (getResources().getDisplayMetrics().density * TAB_SIDE_PADDING_IN_DPS);
134 
135         final TypedArray a = context.obtainStyledAttributes(attrs, ATTRS);
136         mTextSize = a.getDimensionPixelSize(0, 0);
137         mTextStyle = a.getInt(1, 0);
138         mTextColor = a.getColorStateList(2);
139         mTextAllCaps = a.getBoolean(3, false);
140 
141         mTabStrip = new ViewPagerTabStrip(context);
142         addView(mTabStrip,
143                 new FrameLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT));
144         a.recycle();
145 
146         if (CompatUtils.isLollipopCompatible()) {
147             // enable shadow casting from view bounds
148             setOutlineProvider(VIEW_BOUNDS_OUTLINE_PROVIDER);
149         }
150     }
151 
setViewPager(ViewPager viewPager)152     public void setViewPager(ViewPager viewPager) {
153         mPager = viewPager;
154         addTabs(mPager.getAdapter());
155     }
156 
157     /**
158      * Set the tab icons and initialize an array for unread counts the same length as the icon
159      * array.
160      *
161      * @param tabIcons An array representing the tab icons in order.
162      */
configureTabIcons(int[] tabIcons)163     public void configureTabIcons(int[] tabIcons) {
164         mTabIcons = tabIcons;
165         mUnreadCounts = new int[tabIcons.length];
166     }
167 
setUnreadCount(int count, int position)168     public void setUnreadCount(int count, int position) {
169         if (mUnreadCounts == null || position >= mUnreadCounts.length) {
170             return;
171         }
172         mUnreadCounts[position] = count;
173     }
174 
addTabs(PagerAdapter adapter)175     private void addTabs(PagerAdapter adapter) {
176         mTabStrip.removeAllViews();
177 
178         final int count = adapter.getCount();
179         for (int i = 0; i < count; i++) {
180             addTab(adapter.getPageTitle(i), i);
181         }
182     }
183 
addTab(CharSequence tabTitle, final int position)184     private void addTab(CharSequence tabTitle, final int position) {
185         View tabView;
186         if (mTabIcons != null && position < mTabIcons.length) {
187             View layout = LayoutInflater.from(getContext()).inflate(
188                     R.layout.unread_count_tab, null);
189             View iconView = layout.findViewById(R.id.icon);
190             iconView.setBackgroundResource(mTabIcons[position]);
191             iconView.setContentDescription(tabTitle);
192             TextView textView = (TextView) layout.findViewById(R.id.count);
193             if (mUnreadCounts != null && mUnreadCounts[position] > 0) {
194                 textView.setText(Integer.toString(mUnreadCounts[position]));
195                 textView.setVisibility(View.VISIBLE);
196                 iconView.setContentDescription(getResources().getQuantityString(
197                         R.plurals.tab_title_with_unread_items,
198                         mUnreadCounts[position],
199                         tabTitle.toString(),
200                         mUnreadCounts[position]));
201             } else {
202                 textView.setVisibility(View.INVISIBLE);
203                 iconView.setContentDescription(tabTitle);
204             }
205             tabView = layout;
206         } else {
207             final TextView textView = new TextView(getContext());
208             textView.setText(tabTitle);
209             textView.setBackgroundResource(R.drawable.view_pager_tab_background);
210 
211             // Assign various text appearance related attributes to child views.
212             if (mTextStyle > 0) {
213                 textView.setTypeface(textView.getTypeface(), mTextStyle);
214             }
215             if (mTextSize > 0) {
216                 textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, mTextSize);
217             }
218             if (mTextColor != null) {
219                 textView.setTextColor(mTextColor);
220             }
221             textView.setAllCaps(mTextAllCaps);
222             textView.setGravity(Gravity.CENTER);
223 
224             tabView = textView;
225         }
226 
227         tabView.setOnClickListener(new OnClickListener() {
228             @Override
229             public void onClick(View v) {
230                 mPager.setCurrentItem(getRtlPosition(position));
231             }
232         });
233 
234         tabView.setOnLongClickListener(new OnTabLongClickListener(position));
235 
236         tabView.setPadding(mSidePadding, 0, mSidePadding, 0);
237 
238         mTabStrip.addView(tabView, position, new LinearLayout.LayoutParams(
239                 LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT, 1));
240 
241         // Default to the first child being selected
242         if (position == 0) {
243             mPrevSelected = 0;
244             tabView.setSelected(true);
245         }
246     }
247 
248     /**
249      * Remove a tab at a certain index.
250      *
251      * @param index The index of the tab view we wish to remove.
252      */
removeTab(int index)253     public void removeTab(int index) {
254         View view = mTabStrip.getChildAt(index);
255         if (view != null) {
256             mTabStrip.removeView(view);
257         }
258     }
259 
260     /**
261      * Refresh a tab at a certain index by removing it and reconstructing it.
262      *
263      * @param index The index of the tab view we wish to update.
264      */
updateTab(int index)265     public void updateTab(int index) {
266         removeTab(index);
267 
268         if (index < mPager.getAdapter().getCount()) {
269             addTab(mPager.getAdapter().getPageTitle(index), index);
270         }
271     }
272 
273     @Override
onPageScrolled(int position, float positionOffset, int positionOffsetPixels)274     public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
275         position = getRtlPosition(position);
276         int tabStripChildCount = mTabStrip.getChildCount();
277         if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
278             return;
279         }
280 
281         mTabStrip.onPageScrolled(position, positionOffset, positionOffsetPixels);
282     }
283 
284     @Override
onPageSelected(int position)285     public void onPageSelected(int position) {
286         position = getRtlPosition(position);
287         int tabStripChildCount = mTabStrip.getChildCount();
288         if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
289             return;
290         }
291 
292         if (mPrevSelected >= 0 && mPrevSelected < tabStripChildCount) {
293             mTabStrip.getChildAt(mPrevSelected).setSelected(false);
294         }
295         final View selectedChild = mTabStrip.getChildAt(position);
296         selectedChild.setSelected(true);
297 
298         // Update scroll position
299         final int scrollPos = selectedChild.getLeft() - (getWidth() - selectedChild.getWidth()) / 2;
300         smoothScrollTo(scrollPos, 0);
301         mPrevSelected = position;
302     }
303 
304     @Override
onPageScrollStateChanged(int state)305     public void onPageScrollStateChanged(int state) {
306     }
307 
getRtlPosition(int position)308     private int getRtlPosition(int position) {
309         if (getLayoutDirection() == View.LAYOUT_DIRECTION_RTL) {
310             return mTabStrip.getChildCount() - 1 - position;
311         }
312         return position;
313     }
314 }
315 
316