【发布时间】：2013-02-09 03:18:41
【问题描述】：
我正在尝试在horizontal listview 中创建一个通用列表视图。水平滚动很好，但垂直滚动不起作用。我尝试使用this 解决方案，但什么也没发生。我该怎么办？
HorizontalListviewDemo.java
package com.devsmart.android.ui;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout.LayoutParams;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import com.devsmart.android.ui.HorizontialListView;
import com.example.horlistview.R;
public class HorizontalListViewDemo extends Activity {
private final static String ITEM = "item";
private static int COLUMN_COUNT = 20;
private static int ROW_COUNT = 50;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listviewdemo);
HorizontialListView listview = (HorizontialListView) findViewById(R.id.listview);
listview.setAdapter(mAdapter);
}
static class VerticalViewHolder {
protected TextView textview;
}
public void setColumnCount(int n) {
COLUMN_COUNT = n;
}
public void setRowCount(int n) {
ROW_COUNT = n;
}
private BaseAdapter mAdapter = new BaseAdapter() {
public int getCount() {
return COLUMN_COUNT;
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
public View getView(int position, View convertView, ViewGroup parent) {
final List<Map<String, String>> l = createList();
convertView = LayoutInflater.from(parent.getContext()).inflate(R.layout.viewitem, null);
final ListView listview = (ListView) convertView.findViewById(R.id.viewitem_listview);
if (position==0) {
listview.setLayoutParams(new LayoutParams(parent.getWidth()-50, LayoutParams.WRAP_CONTENT));
listview.setAdapter(new SimpleAdapter(
getApplicationContext(),
l,
R.layout.viewitemitem,
new String[] {ITEM},
new int[] {R.id.textView}) {
@Override
public View getView(int position, View convertView, ViewGroup parent) {
VerticalViewHolder verticalViewHolder = null;
if (convertView==null) {
convertView = super.getView(position, convertView, parent);
verticalViewHolder = new VerticalViewHolder();
verticalViewHolder.textview = (TextView) convertView.findViewById(R.id.textView);
LayoutParams lp = (LayoutParams) verticalViewHolder.textview.getLayoutParams();
if (position==0) lp.setMargins(1, 2, 1, 0);
else lp.setMargins(1, 0, 1, 0);
convertView.setTag(verticalViewHolder);
convertView.setTag(R.id.textView, verticalViewHolder.textview);
} else {
verticalViewHolder = (VerticalViewHolder) convertView.getTag();
}
verticalViewHolder.textview.setText(l.get(position).get(ITEM));
return convertView;
}
});
}
else {
if (COLUMN_COUNT>=5)
listview.setLayoutParams(new LayoutParams(parent.getWidth()/5, LayoutParams.WRAP_CONTENT));
else
listview.setLayoutParams(new LayoutParams(parent.getWidth()/COLUMN_COUNT, LayoutParams.WRAP_CONTENT));
listview.setAdapter(new SimpleAdapter(
getApplicationContext(),
l,
R.layout.viewitemitem,
new String[] {ITEM},
new int[] {R.id.textView}) {
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View retval = super.getView(position, convertView, parent);
TextView textview = (TextView) retval.findViewById(R.id.textView);
LayoutParams lp = (LayoutParams) textview.getLayoutParams();
if (position==0) lp.setMargins(0, 2, 1, 0);
else if (position==ROW_COUNT-1) lp.setMargins(0, 0, 1, 1);
else lp.setMargins(0, 0, 1, 0);
return retval;
}
});
}
convertView.setOnTouchListener(new OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
listview.setSmoothScrollbarEnabled(true);
listview.dispatchTouchEvent(event);
return false;
}
});
return convertView;
}
private List<Map<String, String>> createList() {
List<Map<String, String>> values = new ArrayList<Map<String, String>>();
Map<String, String> v = new HashMap<String, String>();
for (int j = 0; j < ROW_COUNT; j++) {
v = new HashMap<String, String>();
v.put(ITEM, ""+j);
values.add(v);
}
return values;
}
};
}
HorizontalListView.java
/*
* HorizontalListView.java v1.5
*
*
* The MIT License
* Copyright (c) 2011 Paul Soucy (paul@dev-smart.com)
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
*/
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 HorizontialListView 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 boolean mDataChanged = false;
public HorizontialListView(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;
}
private DataSetObserver mDataObserver = new DataSetObserver() {
@Override
public void onChanged() {
synchronized(HorizontialListView.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(){
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();
}
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;
}
}
}
public synchronized void scrollTo(int x) {
mScroller.startScroll(mNextX, 0, x - mNextX, 0);
requestLayout();
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
boolean handled = mGesture.onTouchEvent(ev);
return handled;
}
protected boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
synchronized(HorizontialListView.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 HorizontialListView.this.onDown(e);
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
return HorizontialListView.this.onFling(e1, e2, velocityX, velocityY);
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
synchronized(HorizontialListView.this){
mNextX += (int)distanceX;
}
requestLayout();
return true;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent e) {
Rect viewRect = new Rect();
for(int i=0;i<getChildCount();i++){
View child = getChildAt(i);
int left = child.getLeft();
int right = child.getRight();
int top = child.getTop();
int bottom = child.getBottom();
viewRect.set(left, top, right, bottom);
if(viewRect.contains((int)e.getX(), (int)e.getY())){
if(mOnItemClicked != null){
mOnItemClicked.onItemClick(HorizontialListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i ));
}
if(mOnItemSelected != null){
mOnItemSelected.onItemSelected(HorizontialListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i ));
}
break;
}
}
return true;
}
};
}
listviewdemo.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<com.devsmart.android.ui.HorizontialListView
android:id="@+id/listview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#fff"/>
</LinearLayout>
查看项目.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/viewitem_linearlayout"
android:layout_width="wrap_content"
android:layout_height="match_parent" >
<ListView
android:id="@+id/viewitem_listview"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
查看itemitem.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/viewitemitem"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#fff" >
<TextView
android:id="@+id/textView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#000"
android:paddingLeft="3dp"
android:text="@string/hello_world" />
</LinearLayout>
【问题讨论】：
标签： android horizontal-scrolling