PinnedSectionListView在github上的链接地址是&＃xff1a;https://github.com/beworker/pinned-section-listview 。
下载下来后直接将PinnedSectionListView.java&＃xff08;在一些SDK版本拉动的时候会异常崩溃&＃xff0c;异常信息和修改后的文档在后面&＃xff09;复制粘贴在要用的包中&＃xff1a;
activity_main.xml&＃xff1a;
1 <RelativeLayout xmlns:android&＃61;"http://schemas.android.com/apk/res/android"
2 xmlns:tools&＃61;"http://schemas.android.com/tools"
3 android:layout_width&＃61;"match_parent"
4 android:layout_height&＃61;"match_parent"
5 tools:context&＃61;"com.zzw.testpinnedsectionlistview.MainActivity" >
6
7 <com.zzw.testpinnedsectionlistview.PinnedSectionListView
8 android:id&＃61;"&＃64;&＃43;id/listView"
9 android:layout_width&＃61;"match_parent"
10 android:layout_height&＃61;"match_parent" />
11
12 RelativeLayout>
item.xml:
1 xml version&＃61;"1.0" encoding&＃61;"utf-8"?>
2 <RelativeLayout xmlns:android&＃61;"http://schemas.android.com/apk/res/android"
3 android:layout_width&＃61;"match_parent"
4 android:layout_height&＃61;"match_parent"
5 android:orientation&＃61;"vertical" >
6
7 <ImageView
8 android:id&＃61;"&＃64;&＃43;id/imageView"
9 android:layout_width&＃61;"wrap_content"
10 android:layout_height&＃61;"wrap_content"
11 android:layout_alignParentLeft&＃61;"true"
12 android:layout_centerVertical&＃61;"true"
13 android:src&＃61;"&＃64;drawable/ic_launcher" />
14
15 <TextView
16 android:id&＃61;"&＃64;&＃43;id/textView"
17 android:layout_width&＃61;"wrap_content"
18 android:layout_height&＃61;"wrap_content"
19 android:layout_alignBottom&＃61;"&＃64;&＃43;id/imageView1"
20 android:layout_alignParentRight&＃61;"true"
21 android:gravity&＃61;"center"
22 android:textSize&＃61;"20sp"
23 android:layout_alignTop&＃61;"&＃64;&＃43;id/imageView1"
24 android:layout_toRightOf&＃61;"&＃64;&＃43;id/imageView1"
25 android:text&＃61;"TextView" />
26
27 RelativeLayout>
MainActivity.java&＃xff1a;
1 package com.zzw.testpinnedsectionlistview;
2
3 import java.util.ArrayList;
4
5 import com.zzw.testpinnedsectionlistview.PinnedSectionListView.PinnedSectionListAdapter;
6
7 import android.app.Activity;
8 import android.content.Context;
9 import android.graphics.Color;
10 import android.os.Bundle;
11 import android.view.LayoutInflater;
12 import android.view.View;
13 import android.view.ViewGroup;
14 import android.widget.ArrayAdapter;
15 import android.widget.TextView;
16
17 public class MainActivity extends Activity {
18
19 private ArrayList
20
21 private final int VIEW_TYPE_COUNT &＃61; 2;
22
23 &＃64;Override
24 protected void onCreate(Bundle savedInstanceState) {
25 super.onCreate(savedInstanceState);
26 setContentView(R.layout.activity_main);
27
28 items &＃61;new ArrayList
29 // 假设我们演示以A,B,C,,,F这样的字符串作为分组的标签。
30 // 每一组装载5个子数据。
31 String[] groups &＃61; { "A", "B", "C", "D", "E" };
32 for (int i &＃61; 0; i
33 String s &＃61; groups[i];
34
35 Item group &＃61; new Item();
36 group.type &＃61; Item.GROUP;
37 group.text &＃61; s;
38 items.add(group);
39
40 for (int j &＃61; 0; j <10; j&＃43;&＃43;) {
41 Item child &＃61; new Item();
42 child.type &＃61; Item.CHILD;
43 child.text &＃61; s &＃43; "组数据&＃xff1a;" &＃43; j;
44 items.add(child);
45 }
46 }
47
48 PinnedSectionListView listView &＃61; (PinnedSectionListView) findViewById(R.id.listView);
49 listView.setAdapter(new MyAdapter(this, -1));
50
51 }
52
53 private class Item {
54 public static final int GROUP &＃61; 0;
55 public static final int CHILD &＃61; 1;
56
57 public int type;
58 public String text;
59 }
60
61 private class MyAdapter extends ArrayAdapter
62
63 private LayoutInflater inflater;
64
65 public MyAdapter(Context context, int resource) {
66 super(context, resource);
67
68 inflater &＃61; (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
69 }
70
71 &＃64;Override
72 public int getItemViewType(int position) {
73
74 return items.get(position).type;
75 }
76
77 &＃64;Override
78 public int getCount() {
79
80 return items.size();
81 }
82
83 &＃64;Override
84 public int getViewTypeCount() {
85
86 return VIEW_TYPE_COUNT;
87 }
88
89 &＃64;Override
90 public Item getItem(int position) {
91
92 return items.get(position);
93 }
94
95 &＃64;Override
96 public View getView(int position, View convertView, ViewGroup parent) {
97 switch (getItemViewType(position)) {
98 case Item.GROUP:
99
100 if (convertView &＃61;&＃61; null) {
101 convertView &＃61; inflater.inflate(android.R.layout.simple_list_item_1, null);
102 }
103
104 TextView textView_group &＃61; (TextView) convertView.findViewById(android.R.id.text1);
105 textView_group.setText(getItem(position).text);
106 textView_group.setTextColor(Color.BLUE);
107 textView_group.setTextSize(30);
108 textView_group.setBackgroundColor(Color.GRAY);
109
110 break;
111
112 case Item.CHILD:
113 if (convertView &＃61;&＃61; null) {
114 convertView &＃61; inflater.inflate(R.layout.item, null);
115 }
116
117 TextView textView_child &＃61; (TextView) convertView.findViewById(R.id.textView);
118 textView_child.setText(getItem(position).text);
119 textView_child.setBackgroundColor(Color.YELLOW);
120
121 break;
122 }
123 return convertView;
124 }
125
126 /*
127 * 假设此方法返回皆为false。那么PinnedSectionListView将退化成为一个基础的ListView.
128 * 只不过退化后的ListView只是一个拥有两个View Type的ListView。
129 *
130 * 从某种角度上讲&＃xff0c;此方法对于PinnedSectionListView至关重要
131 * 返回值true或false&＃xff0c;将直接导致PinnedSectionListView是一个PinnedSectionListView&＃xff0c;
132 * 还是一个普通的ListView
133 *
134 */
135 &＃64;Override
136 public boolean isItemViewTypePinned(int viewType) {
137 boolean type &＃61; false;
138 switch (viewType) {
139 case Item.GROUP:
140 type &＃61; true;
141 break;
142
143 case Item.CHILD:
144 type &＃61; false;
145 break;
146
147 default:
148 type &＃61; false;
149 break;
150 }
151 return type;
152 }
153 }
154 }
程序运行拉动的时候有的sdk版本会出现程序崩溃&＃xff0c;LogCat是这样情况&＃xff1a;
报错的是原代码PinnedSectionListView.java中的&＃xff08;200行左右&＃xff09;&＃xff1a;
// read layout parametersLayoutParams layoutParams &＃61; (LayoutParams) pinnedView.getLayoutParams();if (layoutParams &＃61;&＃61; null) {layoutParams &＃61; (LayoutParams) generateDefaultLayoutParams();pinnedView.setLayoutParams(layoutParams);}
主要是这句话&＃xff1a;
layoutParams &＃61; (LayoutParams) generateDefaultLayoutParams();
经由研究发现&＃xff0c;此原因是在调用Android系统的generateDefaultLayoutParams()方法时候&＃xff0c;发生异常&＃xff0c;致使代码运行获得的结果layoutParams不正常&＃xff0c;进而导致PinnedSectionListView崩溃。
解决方案&＃xff1a;
自己动手重写Android系统的generateDefaultLayoutParams()方法&＃xff0c;返回自己定制的LayoutParams值。
具体实现&＃xff1a;
在PinnedSectionListView.java中增加自己重写的generateDefaultLayoutParams()方法&＃xff1a;
1 &＃64;Override
2 protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
3
4 LayoutParams mLayoutParams&＃61;new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
5
6 return mLayoutParams;
7 }
最终修复bug&＃xff0c;改进后的PinnedSectionListView.java全部源代码为如下&＃xff08;可直接复制粘贴使用&＃xff09;&＃xff1a;
1 /*
2 * Copyright (C) 2013 Sergej Shafarenka, halfbit.de
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file kt 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.zzw.testpinnedsectionlistview;
18
19
20 import android.content.Context;
21 import android.database.DataSetObserver;
22 import android.graphics.Canvas;
23 import android.graphics.Color;
24 import android.graphics.PointF;
25 import android.graphics.Rect;
26 import android.graphics.drawable.GradientDrawable;
27 import android.graphics.drawable.GradientDrawable.Orientation;
28 import android.os.Parcelable;
29 import android.util.AttributeSet;
30 import android.view.MotionEvent;
31 import android.view.SoundEffectConstants;
32 import android.view.View;
33 import android.view.ViewConfiguration;
34 import android.view.ViewGroup;
35 import android.view.accessibility.AccessibilityEvent;
36 import android.widget.AbsListView;
37 import android.widget.HeaderViewListAdapter;
38 import android.widget.ListAdapter;
39 import android.widget.ListView;
40 import android.widget.SectionIndexer;
41
42
43 /**
44 * ListView, which is capable to pin section views at its top while the rest is still scrolled.
45 */
46 public class PinnedSectionListView extends ListView {
47
48 //-- inner classes
49
50 /** List adapter to be implemented for being used with PinnedSectionListView adapter. */
51 public static interface PinnedSectionListAdapter extends ListAdapter {
52 /** This method shall return &＃39;true&＃39; if views of given type has to be pinned. */
53 boolean isItemViewTypePinned(int viewType);
54 }
55
56 /** Wrapper class for pinned section view and its position in the list. */
57 static class PinnedSection {
58 public View view;
59 public int position;
60 public long id;
61 }
62
63 //-- class fields
64
65 // fields used for handling touch events
66 private final Rect mTouchRect &＃61; new Rect();
67 private final PointF mTouchPoint &＃61; new PointF();
68 private int mTouchSlop;
69 private View mTouchTarget;
70 private MotionEvent mDownEvent;
71
72 // fields used for drawing shadow under a pinned section
73 private GradientDrawable mShadowDrawable;
74 private int mSectionsDistanceY;
75 private int mShadowHeight;
76
77 /** Delegating listener, can be null. */
78 OnScrollListener mDelegateOnScrollListener;
79
80 /** Shadow for being recycled, can be null. */
81 PinnedSection mRecycleSection;
82
83 /** shadow instance with a pinned view, can be null. */
84 PinnedSection mPinnedSection;
85
86 /** Pinned view Y-translation. We use it to stick pinned view to the next section. */
87 int mTranslateY;
88
89 /** Scroll listener which does the magic */
90 private final OnScrollListener mOnScrollListener &＃61; new OnScrollListener() {
91
92 &＃64;Override public void onScrollStateChanged(AbsListView view, int scrollState) {
93 if (mDelegateOnScrollListener !&＃61; null) { // delegate
94 mDelegateOnScrollListener.onScrollStateChanged(view, scrollState);
95 }
96 }
97
98 &＃64;Override
99 public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
100
101 if (mDelegateOnScrollListener !&＃61; null) { // delegate
102 mDelegateOnScrollListener.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount);
103 }
104
105 // get expected adapter or fail fast
106 ListAdapter adapter &＃61; getAdapter();
107 if (adapter &＃61;&＃61; null || visibleItemCount &＃61;&＃61; 0) return; // nothing to do
108
109 final boolean isFirstVisibleItemSection &＃61;
110 isItemViewTypePinned(adapter, adapter.getItemViewType(firstVisibleItem));
111
112 if (isFirstVisibleItemSection) {
113 View sectionView &＃61; getChildAt(0);
114 if (sectionView.getTop() &＃61;&＃61; getPaddingTop()) { // view sticks to the top, no need for pinned shadow
115 destroyPinnedShadow();
116 } else { // section doesn&＃39;t stick to the top, make sure we have a pinned shadow
117 ensureShadowForPosition(firstVisibleItem, firstVisibleItem, visibleItemCount);
118 }
119
120 } else { // section is not at the first visible position
121 int sectionPosition &＃61; findCurrentSectionPosition(firstVisibleItem);
122 if (sectionPosition > -1) { // we have section position
123 ensureShadowForPosition(sectionPosition, firstVisibleItem, visibleItemCount);
124 } else { // there is no section for the first visible item, destroy shadow
125 destroyPinnedShadow();
126 }
127 }
128 };
129
130 };
131
132 /** Default change observer. */
133 private final DataSetObserver mDataSetObserver &＃61; new DataSetObserver() {
134 &＃64;Override public void onChanged() {
135 recreatePinnedShadow();
136 };
137 &＃64;Override public void onInvalidated() {
138 recreatePinnedShadow();
139 }
140 };
141
142 //-- constructors
143
144 public PinnedSectionListView(Context context, AttributeSet attrs) {
145 super(context, attrs);
146 initView();
147 }
148
149 public PinnedSectionListView(Context context, AttributeSet attrs, int defStyle) {
150 super(context, attrs, defStyle);
151 initView();
152 }
153
154 private void initView() {
155 setOnScrollListener(mOnScrollListener);
156 mTouchSlop &＃61; ViewConfiguration.get(getContext()).getScaledTouchSlop();
157 initShadow(true);
158 }
159
160 //-- public API methods
161
162 public void setShadowVisible(boolean visible) {
163 initShadow(visible);
164 if (mPinnedSection !&＃61; null) {
165 View v &＃61; mPinnedSection.view;
166 invalidate(v.getLeft(), v.getTop(), v.getRight(), v.getBottom() &＃43; mShadowHeight);
167 }
168 }
169
170 //-- pinned section drawing methods
171
172 public void initShadow(boolean visible) {
173 if (visible) {
174 if (mShadowDrawable &＃61;&＃61; null) {
175 mShadowDrawable &＃61; new GradientDrawable(Orientation.TOP_BOTTOM,
176 new int[] { Color.parseColor("#ffa0a0a0"), Color.parseColor("#50a0a0a0"), Color.parseColor("#00a0a0a0")});
177 mShadowHeight &＃61; (int) (8 * getResources().getDisplayMetrics().density);
178 }
179 } else {
180 if (mShadowDrawable !&＃61; null) {
181 mShadowDrawable &＃61; null;
182 mShadowHeight &＃61; 0;
183 }
184 }
185 }
186
187 //*****添加*****//
188 &＃64;Override
189 protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
190 LayoutParams mLayoutParams&＃61;new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT);
191 return mLayoutParams;
192 }
193 //*****添加*****//
194
195 /** Create shadow wrapper with a pinned view for a view at given position */
196 void createPinnedShadow(int position) {
197
198 // try to recycle shadow
199 PinnedSection pinnedShadow &＃61; mRecycleSection;
200 mRecycleSection &＃61; null;
201
202 // create new shadow, if needed
203 if (pinnedShadow &＃61;&＃61; null) pinnedShadow &＃61; new PinnedSection();
204 // request new view using recycled view, if such
205 View pinnedView &＃61; getAdapter().getView(position, pinnedShadow.view, PinnedSectionListView.this);
206
207 // read layout parameters
208 LayoutParams layoutParams &＃61; (LayoutParams) pinnedView.getLayoutParams();
209 if (layoutParams &＃61;&＃61; null) {
210 layoutParams &＃61; (LayoutParams) generateDefaultLayoutParams();
211 pinnedView.setLayoutParams(layoutParams);
212 }
213
214 int heightMode &＃61; MeasureSpec.getMode(layoutParams.height);
215 int heightSize &＃61; MeasureSpec.getSize(layoutParams.height);
216
217 if (heightMode &＃61;&＃61; MeasureSpec.UNSPECIFIED) heightMode &＃61; MeasureSpec.EXACTLY;
218
219 int maxHeight &＃61; getHeight() - getListPaddingTop() - getListPaddingBottom();
220 if (heightSize > maxHeight) heightSize &＃61; maxHeight;
221
222 // measure & layout
223 int ws &＃61; MeasureSpec.makeMeasureSpec(getWidth() - getListPaddingLeft() - getListPaddingRight(), MeasureSpec.EXACTLY);
224 int hs &＃61; MeasureSpec.makeMeasureSpec(heightSize, heightMode);
225 pinnedView.measure(ws, hs);
226 pinnedView.layout(0, 0, pinnedView.getMeasuredWidth(), pinnedView.getMeasuredHeight());
227 mTranslateY &＃61; 0;
228
229 // initialize pinned shadow
230 pinnedShadow.view &＃61; pinnedView;
231 pinnedShadow.position &＃61; position;
232 pinnedShadow.id &＃61; getAdapter().getItemId(position);
233
234 // store pinned shadow
235 mPinnedSection &＃61; pinnedShadow;
236 }
237
238 /** Destroy shadow wrapper for currently pinned view */
239 void destroyPinnedShadow() {
240 if (mPinnedSection !&＃61; null) {
241 // keep shadow for being recycled later
242 mRecycleSection &＃61; mPinnedSection;
243 mPinnedSection &＃61; null;
244 }
245 }
246
247 /** Makes sure we have an actual pinned shadow for given position. */
248 void ensureShadowForPosition(int sectionPosition, int firstVisibleItem, int visibleItemCount) {
249 if (visibleItemCount <2) { // no need for creating shadow at all, we have a single visible item
250 destroyPinnedShadow();
251 return;
252 }
253
254 if (mPinnedSection !&＃61; null
255 && mPinnedSection.position !&＃61; sectionPosition) { // invalidate shadow, if required
256 destroyPinnedShadow();
257 }
258
259 if (mPinnedSection &＃61;&＃61; null) { // create shadow, if empty
260 createPinnedShadow(sectionPosition);
261 }
262
263 // align shadow according to next section position, if needed
264 int nextPosition &＃61; sectionPosition &＃43; 1;
265 if (nextPosition < getCount()) {
266 int nextSectionPosition &＃61; findFirstVisibleSectionPosition(nextPosition,
267 visibleItemCount - (nextPosition - firstVisibleItem));
268 if (nextSectionPosition > -1) {
269 View nextSectionView &＃61; getChildAt(nextSectionPosition - firstVisibleItem);
270 final int bottom &＃61; mPinnedSection.view.getBottom() &＃43; getPaddingTop();
271 mSectionsDistanceY &＃61; nextSectionView.getTop() - bottom;
272 if (mSectionsDistanceY <0) {
273 // next section overlaps pinned shadow, move it up
274 mTranslateY &＃61; mSectionsDistanceY;
275 } else {
276 // next section does not overlap with pinned, stick to top
277 mTranslateY &＃61; 0;
278 }
279 } else {
280 // no other sections are visible, stick to top
281 mTranslateY &＃61; 0;
282 mSectionsDistanceY &＃61; Integer.MAX_VALUE;
283 }
284 }
285
286 }
287
288 int findFirstVisibleSectionPosition(int firstVisibleItem, int visibleItemCount) {
289 ListAdapter adapter &＃61; getAdapter();
290
291 int adapterDataCount &＃61; adapter.getCount();
292 if (getLastVisiblePosition() >&＃61; adapterDataCount) return -1; // dataset has changed, no candidate
293
294 if (firstVisibleItem&＃43;visibleItemCount >&＃61; adapterDataCount){//added to prevent index Outofbound (in case)
295 visibleItemCount &＃61; adapterDataCount-firstVisibleItem;
296 }
297
298 for (int childIndex &＃61; 0; childIndex
299 int position &＃61; firstVisibleItem &＃43; childIndex;
300 int viewType &＃61; adapter.getItemViewType(position);
301 if (isItemViewTypePinned(adapter, viewType)) return position;
302 }
303 return -1;
304 }
305
306 int findCurrentSectionPosition(int fromPosition) {
307 ListAdapter adapter &＃61; getAdapter();
308
309 if (fromPosition >&＃61; adapter.getCount()) return -1; // dataset has changed, no candidate
310
311 if (adapter instanceof SectionIndexer) {
312 // try fast way by asking section indexer
313 SectionIndexer indexer &＃61; (SectionIndexer) adapter;
314 int sectionPosition &＃61; indexer.getSectionForPosition(fromPosition);
315 int itemPosition &＃61; indexer.getPositionForSection(sectionPosition);
316 int typeView &＃61; adapter.getItemViewType(itemPosition);
317 if (isItemViewTypePinned(adapter, typeView)) {
318 return itemPosition;
319 } // else, no luck
320 }
321
322 // try slow way by looking through to the next section item above
323 for (int position&＃61;fromPosition; position>&＃61;0; position--) {
324 int viewType &＃61; adapter.getItemViewType(position);
325 if (isItemViewTypePinned(adapter, viewType)) return position;
326 }
327 return -1; // no candidate found
328 }
329
330 void recreatePinnedShadow() {
331 destroyPinnedShadow();
332 ListAdapter adapter &＃61; getAdapter();
333 if (adapter !&＃61; null && adapter.getCount() > 0) {
334 int firstVisiblePosition &＃61; getFirstVisiblePosition();
335 int sectionPosition &＃61; findCurrentSectionPosition(firstVisiblePosition);
336 if (sectionPosition &＃61;&＃61; -1) return; // no views to pin, exit
337 ensureShadowForPosition(sectionPosition,
338 firstVisiblePosition, getLastVisiblePosition() - firstVisiblePosition);
339 }
340 }
341
342 &＃64;Override
343 public void setOnScrollListener(OnScrollListener listener) {
344 if (listener &＃61;&＃61; mOnScrollListener) {
345 super.setOnScrollListener(listener);
346 } else {
347 mDelegateOnScrollListener &＃61; listener;
348 }
349 }
350
351 &＃64;Override
352 public void onRestoreInstanceState(Parcelable state) {
353 super.onRestoreInstanceState(state);
354 post(new Runnable() {
355 &＃64;Override public void run() { // restore pinned view after configuration change
356 recreatePinnedShadow();
357 }
358 });
359 }
360
361 &＃64;Override
362 public void setAdapter(ListAdapter adapter) {
363
364 // assert adapter in debug mode
365 if (BuildConfig.DEBUG && adapter !&＃61; null) {
366 if (!(adapter instanceof PinnedSectionListAdapter))
367 throw new IllegalArgumentException("Does your adapter implement PinnedSectionListAdapter?");
368 if (adapter.getViewTypeCount() <2)
369 throw new IllegalArgumentException("Does your adapter handle at least two types" &＃43;
370 " of views in getViewTypeCount() method: items and sections?");
371 }
372
373 // unregister observer at old adapter and register on new one
374 ListAdapter oldAdapter &＃61; getAdapter();
375 if (oldAdapter !&＃61; null) oldAdapter.unregisterDataSetObserver(mDataSetObserver);
376 if (adapter !&＃61; null) adapter.registerDataSetObserver(mDataSetObserver);
377
378 // destroy pinned shadow, if new adapter is not same as old one
379 if (oldAdapter !&＃61; adapter) destroyPinnedShadow();
380
381 super.setAdapter(adapter);
382 }
383
384 &＃64;Override
385 protected void onLayout(boolean changed, int l, int t, int r, int b) {
386 super.onLayout(changed, l, t, r, b);
387 if (mPinnedSection !&＃61; null) {
388 int parentWidth &＃61; r - l - getPaddingLeft() - getPaddingRight();
389 int shadowWidth &＃61; mPinnedSection.view.getWidth();
390 if (parentWidth !&＃61; shadowWidth) {
391 recreatePinnedShadow();
392 }
393 }
394 }
395
396 &＃64;Override
397 protected void dispatchDraw(Canvas canvas) {
398 super.dispatchDraw(canvas);
399
400 if (mPinnedSection !&＃61; null) {
401
402 // prepare variables
403 int pLeft &＃61; getListPaddingLeft();
404 int pTop &＃61; getListPaddingTop();
405 View view &＃61; mPinnedSection.view;
406
407 // draw child
408 canvas.save();
409
410 int clipHeight &＃61; view.getHeight() &＃43;
411 (mShadowDrawable &＃61;&＃61; null ? 0 : Math.min(mShadowHeight, mSectionsDistanceY));
412 canvas.clipRect(pLeft, pTop, pLeft &＃43; view.getWidth(), pTop &＃43; clipHeight);
413
414 canvas.translate(pLeft, pTop &＃43; mTranslateY);
415 drawChild(canvas, mPinnedSection.view, getDrawingTime());
416
417 if (mShadowDrawable !&＃61; null && mSectionsDistanceY > 0) {
418 mShadowDrawable.setBounds(mPinnedSection.view.getLeft(),
419 mPinnedSection.view.getBottom(),
420 mPinnedSection.view.getRight(),
421 mPinnedSection.view.getBottom() &＃43; mShadowHeight);
422 mShadowDrawable.draw(canvas);
423 }
424
425 canvas.restore();
426 }
427 }
428
429 //-- touch handling methods
430
431 &＃64;Override
432 public boolean dispatchTouchEvent(MotionEvent ev) {
433
434 final float x &＃61; ev.getX();
435 final float y &＃61; ev.getY();
436 final int action &＃61; ev.getAction();
437
438 if (action &＃61;&＃61; MotionEvent.ACTION_DOWN
439 && mTouchTarget &＃61;&＃61; null
440 && mPinnedSection !&＃61; null
441 && isPinnedViewTouched(mPinnedSection.view, x, y)) { // create touch target
442
443 // user touched pinned view
444 mTouchTarget &＃61; mPinnedSection.view;
445 mTouchPoint.x &＃61; x;
446 mTouchPoint.y &＃61; y;
447
448 // copy down event for eventually be used later
449 mDownEvent &＃61; MotionEvent.obtain(ev);
450 }
451
452 if (mTouchTarget !&＃61; null) {
453 if (isPinnedViewTouched(mTouchTarget, x, y)) { // forward event to pinned view
454 mTouchTarget.dispatchTouchEvent(ev);
455 }
456
457 if (action &＃61;&＃61; MotionEvent.ACTION_UP) { // perform onClick on pinned view
458 super.dispatchTouchEvent(ev);
459 performPinnedItemClick();
460 clearTouchTarget();
461
462 } else if (action &＃61;&＃61; MotionEvent.ACTION_CANCEL) { // cancel
463 clearTouchTarget();
464
465 } else if (action &＃61;&＃61; MotionEvent.ACTION_MOVE) {
466 if (Math.abs(y - mTouchPoint.y) > mTouchSlop) {
467
468 // cancel sequence on touch target
469 MotionEvent event &＃61; MotionEvent.obtain(ev);
470 event.setAction(MotionEvent.ACTION_CANCEL);
471 mTouchTarget.dispatchTouchEvent(event);
472 event.recycle();
473
474 // provide correct sequence to super class for further handling
475 super.dispatchTouchEvent(mDownEvent);
476 super.dispatchTouchEvent(ev);
477 clearTouchTarget();
478
479 }
480 }
481
482 return true;
483 }
484
485 // call super if this was not our pinned view
486 return super.dispatchTouchEvent(ev);
487 }
488
489 private boolean isPinnedViewTouched(View view, float x, float y) {
490 view.getHitRect(mTouchRect);
491
492 // by taping top or bottom padding, the list performs on click on a border item.
493 // we don&＃39;t add top padding here to keep behavior consistent.
494 mTouchRect.top &＃43;&＃61; mTranslateY;
495
496 mTouchRect.bottom &＃43;&＃61; mTranslateY &＃43; getPaddingTop();
497 mTouchRect.left &＃43;&＃61; getPaddingLeft();
498 mTouchRect.right -&＃61; getPaddingRight();
499 return mTouchRect.contains((int)x, (int)y);
500 }
501
502 private void clearTouchTarget() {
503 mTouchTarget &＃61; null;
504 if (mDownEvent !&＃61; null) {
505 mDownEvent.recycle();
506 mDownEvent &＃61; null;
507 }
508 }
509
510 private boolean performPinnedItemClick() {
511 if (mPinnedSection &＃61;&＃61; null) return false;
512
513 OnItemClickListener listener &＃61; getOnItemClickListener();
514 if (listener !&＃61; null && getAdapter().isEnabled(mPinnedSection.position)) {
515 View view &＃61; mPinnedSection.view;
516 playSoundEffect(SoundEffectConstants.CLICK);
517 if (view !&＃61; null) {
518 view.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_CLICKED);
519 }
520 listener.onItemClick(this, view, mPinnedSection.position, mPinnedSection.id);
521 return true;
522 }
523 return false;
524 }
525
526 public static boolean isItemViewTypePinned(ListAdapter adapter, int viewType) {
527 if (adapter instanceof HeaderViewListAdapter) {
528 adapter &＃61; ((HeaderViewListAdapter)adapter).getWrappedAdapter();
529 }
530 return ((PinnedSectionListAdapter) adapter).isItemViewTypePinned(viewType);
531 }
532
533 }
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