Android开源：水平方向listview,HorizontalListView
用法：
与普通listview一样。
项目地址:https://github.com/dinocore1/DevsmartLib-Android
代码：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
|
package
com.devsmart.android.ui;
import
java.util.LinkedList;
import
java.util.Queue;
import
android.content.Context;
import
android.database.DataSetObserver;
import
android.graphics.Rect;
import
android.util.AttributeSet;
import
android.view.GestureDetector;
import
android.view.GestureDetector.OnGestureListener;
import
android.view.MotionEvent;
import
android.view.View;
import
android.widget.AdapterView;
import
android.widget.ListAdapter;
import
android.widget.Scroller;
public
class
HorizontalListView
extends
AdapterView<ListAdapter> {
public
boolean
mAlwaysOverrideTouch =
true
;
protected
ListAdapter mAdapter;
private
int
mLeftViewIndex = -
1
;
private
int
mRightViewIndex =
0
;
protected
int
mCurrentX;
protected
int
mNextX;
private
int
mMaxX = Integer.MAX_VALUE;
private
int
mDisplayOffset =
0
;
protected
Scroller mScroller;
private
GestureDetector mGesture;
private
Queue<View> mRemovedViewQueue =
new
LinkedList<View>();
private
OnItemSelectedListener mOnItemSelected;
private
OnItemClickListener mOnItemClicked;
private
OnItemLongClickListener mOnItemLongClicked;
private
boolean
mDataChanged =
false
;
public
HorizontalListView(Context context, AttributeSet attrs) {
super
(context, attrs);
initView();
}
private
synchronized
void
initView() {
mLeftViewIndex = -
1
;
mRightViewIndex =
0
;
mDisplayOffset =
0
;
mCurrentX =
0
;
mNextX =
0
;
mMaxX = Integer.MAX_VALUE;
mScroller =
new
Scroller(getContext());
mGesture =
new
GestureDetector(getContext(), mOnGesture);
}
@Override
public
void
setOnItemSelectedListener(AdapterView.OnItemSelectedListener listener) {
mOnItemSelected = listener;
}
@Override
public
void
setOnItemClickListener(AdapterView.OnItemClickListener listener){
mOnItemClicked = listener;
}
@Override
public
void
setOnItemLongClickListener(AdapterView.OnItemLongClickListener listener) {
mOnItemLongClicked = listener;
}
private
DataSetObserver mDataObserver =
new
DataSetObserver() {
@Override
public
void
onChanged() {
synchronized
(HorizontalListView.
this
){
mDataChanged =
true
;
}
invalidate();
requestLayout();
}
@Override
public
void
onInvalidated() {
reset();
invalidate();
requestLayout();
}
};
@Override
public
ListAdapter getAdapter() {
return
mAdapter;
}
@Override
public
View getSelectedView() {
//TODO: implement
return
null
;
}
@Override
public
void
setAdapter(ListAdapter adapter) {
if
(mAdapter !=
null
) {
mAdapter.unregisterDataSetObserver(mDataObserver);
}
mAdapter = adapter;
mAdapter.registerDataSetObserver(mDataObserver);
reset();
}
private
synchronized
void
reset(){
initView();
removeAllViewsInLayout();
requestLayout();
}
@Override
public
void
setSelection(
int
position) {
//TODO: implement
}
private
void
addAndMeasureChild(
final
View child,
int
viewPos) {
LayoutParams params = child.getLayoutParams();
if
(params ==
null
) {
params =
new
LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
}
addViewInLayout(child, viewPos, params,
true
);
child.measure(MeasureSpec.makeMeasureSpec(getWidth(), MeasureSpec.AT_MOST),
MeasureSpec.makeMeasureSpec(getHeight(), MeasureSpec.AT_MOST));
}
@Override
protected
synchronized
void
onLayout(
boolean
changed,
int
left,
int
top,
int
right,
int
bottom) {
super
.onLayout(changed, left, top, right, bottom);
if
(mAdapter ==
null
){
return
;
}
if
(mDataChanged){
int
oldCurrentX = mCurrentX;
initView();
removeAllViewsInLayout();
mNextX = oldCurrentX;
mDataChanged =
false
;
}
if
(mScroller.computeScrollOffset()){
int
scrollx = mScroller.getCurrX();
mNextX = scrollx;
}
if
(mNextX <=
0
){
mNextX =
0
;
mScroller.forceFinished(
true
);
}
if
(mNextX >= mMaxX) {
mNextX = mMaxX;
mScroller.forceFinished(
true
);
}
int
dx = mCurrentX - mNextX;
removeNonVisibleItems(dx);
fillList(dx);
positionItems(dx);
mCurrentX = mNextX;
if
(!mScroller.isFinished()){
post(
new
Runnable(){
@Override
public
void
run() {
requestLayout();
}
});
}
}
private
void
fillList(
final
int
dx) {
int
edge =
0
;
View child = getChildAt(getChildCount()-
1
);
if
(child !=
null
) {
edge = child.getRight();
}
fillListRight(edge, dx);
edge =
0
;
child = getChildAt(
0
);
if
(child !=
null
) {
edge = child.getLeft();
}
fillListLeft(edge, dx);
}
private
void
fillListRight(
int
rightEdge,
final
int
dx) {
while
(rightEdge + dx < getWidth() && mRightViewIndex < mAdapter.getCount()) {
View child = mAdapter.getView(mRightViewIndex, mRemovedViewQueue.poll(),
this
);
addAndMeasureChild(child, -
1
);
rightEdge += child.getMeasuredWidth();
if
(mRightViewIndex == mAdapter.getCount()-
1
) {
mMaxX = mCurrentX + rightEdge - getWidth();
}
if
(mMaxX <
0
) {
mMaxX =
0
;
}
mRightViewIndex++;
}
}
private
void
fillListLeft(
int
leftEdge,
final
int
dx) {
while
(leftEdge + dx >
0
&& mLeftViewIndex >=
0
) {
View child = mAdapter.getView(mLeftViewIndex, mRemovedViewQueue.poll(),
this
);
addAndMeasureChild(child,
0
);
leftEdge -= child.getMeasuredWidth();
mLeftViewIndex--;
mDisplayOffset -= child.getMeasuredWidth();
}
}
private
void
removeNonVisibleItems(
final
int
dx) {
View child = getChildAt(
0
);
while
(child !=
null
&& child.getRight() + dx <=
0
) {
mDisplayOffset += child.getMeasuredWidth();
mRemovedViewQueue.offer(child);
removeViewInLayout(child);
mLeftViewIndex++;
child = getChildAt(
0
);
}
child = getChildAt(getChildCount()-
1
);
while
(child !=
null
&& child.getLeft() + dx >= getWidth()) {
mRemovedViewQueue.offer(child);
removeViewInLayout(child);
mRightViewIndex--;
child = getChildAt(getChildCount()-
1
);
}
}
private
void
positionItems(
final
int
dx) {
if
(getChildCount() >
0
){
mDisplayOffset += dx;
int
left = mDisplayOffset;
for
(
int
i=
0
;i<getChildCount();i++){
View child = getChildAt(i);
int
childWidth = child.getMeasuredWidth();
child.layout(left,
0
, left + childWidth, child.getMeasuredHeight());
left += childWidth + child.getPaddingRight();
}
}
}
public
synchronized
void
scrollTo(
int
x) {
mScroller.startScroll(mNextX,
0
, x - mNextX,
0
);
requestLayout();
}
@Override
public
boolean
dispatchTouchEvent(MotionEvent ev) {
boolean
handled =
super
.dispatchTouchEvent(ev);
handled |= mGesture.onTouchEvent(ev);
return
handled;
}
protected
boolean
onFling(MotionEvent e1, MotionEvent e2,
float
velocityX,
float
velocityY) {
synchronized
(HorizontalListView.
this
){
mScroller.fling(mNextX,
0
, (
int
)-velocityX,
0
,
0
, mMaxX,
0
,
0
);
}
requestLayout();
return
true
;
}
protected
boolean
onDown(MotionEvent e) {
mScroller.forceFinished(
true
);
return
true
;
}
private
OnGestureListener mOnGesture =
new
GestureDetector.SimpleOnGestureListener() {
@Override
public
boolean
onDown(MotionEvent e) {
return
HorizontalListView.
this
.onDown(e);
}
@Override
public
boolean
onFling(MotionEvent e1, MotionEvent e2,
float
velocityX,
float
velocityY) {
return
HorizontalListView.
this
.onFling(e1, e2, velocityX, velocityY);
}
@Override
public
boolean
onScroll(MotionEvent e1, MotionEvent e2,
float
distanceX,
float
distanceY) {
synchronized
(HorizontalListView.
this
){
mNextX += (
int
)distanceX;
}
requestLayout();
return
true
;
}
@Override
public
boolean
onSingleTapConfirmed(MotionEvent e) {
for
(
int
i=
0
;i<getChildCount();i++){
View child = getChildAt(i);
if
(isEventWithinView(e, child)) {
if
(mOnItemClicked !=
null
){
mOnItemClicked.onItemClick(HorizontalListView.
this
, child, mLeftViewIndex +
1
+ i, mAdapter.getItemId( mLeftViewIndex +
1
+ i ));
}
if
(mOnItemSelected !=
null
){
mOnItemSelected.onItemSelected(HorizontalListView.
this
, child, mLeftViewIndex +
1
+ i, mAdapter.getItemId( mLeftViewIndex +
1
+ i ));
}
break
;
}
}
return
true
;
}
@Override
public
void
onLongPress(MotionEvent e) {
int
childCount = getChildCount();
for
(
int
i =
0
; i < childCount; i++) {
View child = getChildAt(i);
if
(isEventWithinView(e, child)) {
if
(mOnItemLongClicked !=
null
) {
mOnItemLongClicked.onItemLongClick(HorizontalListView.
this
, child, mLeftViewIndex +
1
+ i, mAdapter.getItemId(mLeftViewIndex +
1
+ i));
}
break
;
}
}
}
private
boolean
isEventWithinView(MotionEvent e, View child) {
Rect viewRect =
new
Rect();
int
[] childPosition =
new
int
[
2
];
child.getLocationOnScreen(childPosition);
int
left = childPosition[
0
];
int
right = left + child.getWidth();
int
top = childPosition[
1
];
int
bottom = top + child.getHeight();
viewRect.set(left, top, right, bottom);
return
viewRect.contains((
int
) e.getRawX(), (
int
) e.getRawY());
}
};
}
|
本文转自 glblong 51CTO博客，原文链接：http://blog.51cto.com/glblong/1307725，如需转载请自行联系原作者
