Android 之 XHorizontalListView横向滑动列表，并默认第一个选中

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 XHorizontalListView 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 XHorizontalListView(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(XHorizontalListView.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(XHorizontalListView.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 XHorizontalListView.this.onDown(e);
}

@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
return XHorizontalListView.this.onFling(e1, e2, velocityX, velocityY);
}

@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {

synchronized(XHorizontalListView.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(XHorizontalListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i ));
}
if(mOnItemSelected != null){
mOnItemSelected.onItemSelected(XHorizontalListView.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(XHorizontalListView.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());
}
};

}

import java.util.ArrayList;
import java.util.List;

import org.yanzi.ui.HorizontalListViewAdapter;
import org.yanzi.ui.XHorizontalListView;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Toast;

public class MainActivity extends Activity {
XHorizontalListView hListView;
HorizontalListViewAdapter hListViewAdapter;
List<HorizontalListViewInfo>  lists=new ArrayList<HorizontalListViewInfo>();

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

//
lists.add(new HorizontalListViewInfo("酒店", R.drawable.hotel1,R.drawable.hotel,true));
lists.add(new HorizontalListViewInfo("航空", R.drawable.plane,R.drawable.plane1,false));
lists.add(new HorizontalListViewInfo("高尔夫", R.drawable.food,R.drawable.food1,false));
lists.add(new HorizontalListViewInfo("健康医疗", R.drawable.health,R.drawable.health1,false));
lists.add(new HorizontalListViewInfo("美食", R.drawable.golf,R.drawable.golf1,false));
lists.add(new HorizontalListViewInfo("其他", R.drawable.other,R.drawable.other1,false));
initUI();
}

public void initUI() {
hListView = (XHorizontalListView) findViewById(R.id.horizon_listview);
hListViewAdapter = new HorizontalListViewAdapter(getApplicationContext(),lists);
hListView.setAdapter(hListViewAdapter);

//
hListView.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// TODO Auto-generated method stub
HorizontalListViewInfo info=(HorizontalListViewInfo) hListViewAdapter.getItem(position);

Toast.makeText(MainActivity.this, info.getName(), 1).show();

for (int i = 0; i <lists.size(); i++) {
if(lists.get(i).getName().equals(info.getName())){
lists.get(i).setIschick(true);
}else {
lists.get(i).setIschick(false);
}
}

hListViewAdapter.notifyDataSetChanged();

}
});
}

}

import java.util.List;

import org.yanzi.testhorizontallistview.HorizontalListViewInfo;
import org.yanzi.testhorizontallistview.R;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class HorizontalListViewAdapter extends BaseAdapter{
private Context mContext;
private LayoutInflater mInflater;

private List<HorizontalListViewInfo> lists;

public HorizontalListViewAdapter(Context context,List<HorizontalListViewInfo> lists){
this.mContext = context;
this.lists=lists;
mInflater=(LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);//LayoutInflater.from(mContext);
}
@Override
public int getCount() {
return lists.size();
}
@Override
public Object getItem(int position) {
return lists.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

ViewHolder holder;
if(convertView==null){
holder = new ViewHolder();
convertView = mInflater.inflate(R.layout.horizontal_list_item, null);
holder.isImage=(ImageView)convertView.findViewById(R.id.img_list_item);
holder.mTitle=(TextView)convertView.findViewById(R.id.text_list_item);
convertView.setTag(holder);
}else{
holder=(ViewHolder)convertView.getTag();
}

holder.mTitle.setText(lists.get(position).getName());

if(lists.get(position).isIschick()){
holder.isImage.setImageResource(lists.get(position).getIsimage());
}else {
holder.isImage.setImageResource(lists.get(position).getImage());
}

return convertView;
}

private static class ViewHolder {
private TextView mTitle ;
private ImageView isImage;
}

}