(1)比如每页显示2X2，总共2XN，每个item显示图片+文字（点击有链接）。
如果单行水平滚动，可以用Horizontalscrollview实现。
如果是多行水平滚动，则结合Gridview（一般是垂直滚动的）和Horizontalscrollview实现。
(2)水平滚动翻页，下面有显示当前页的icon。
1.实现自定义的HorizontalScrollView(HorizontalScrollView.java)：
因为要翻页时需要传当前页给调用者，所以fling函数中自己实现而不要调用父类的fling。
代码如下:
public class DrawerHScrollView extends HorizontalScrollView {
private static final String TAG = "DrawerHScrollView";
private IDrawerPresenter drawerPresenter = null;
private int currentPage = 0;
private int totalPages = 1;
private static Hashtable positionLeftTopOfPages = new Hashtable();
public DrawerHScrollView(Context context) {
super(context);
}
public DrawerHScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public DrawerHScrollView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public void cleanup(){
currentPage = 0;
totalPages = 1;
drawerPresenter = null;
if(positionLeftTopOfPages != null){
positionLeftTopOfPages.clear();
}
}
public void setParameters(int totalPages, int currentPage, int scrollDisX) {
Log.d(TAG, "~~~~~setParameters totalPages:"+totalPages +",currentPage:"+ currentPage +",scrollDisX:"+scrollDisX);
this.totalPages = totalPages;
this.currentPage = currentPage;
positionLeftTopOfPages.clear();
for (int i = 0;i 0 && (currentPage < totalPages - 1)){
currentPage++;
change_flag = true;
} else if (velocityX < 0 && (currentPage > 0)){
currentPage--;
change_flag = true;
}
if (change_flag){
int postionTo = (Integer)positionLeftTopOfPages.get(new Integer(currentPage)).intValue();
Log.v(TAG, "------smoothScrollTo posx:"+postionTo);
smoothScrollTo(postionTo, 0);
drawerPresenter.dispatchEvent(totalPages, currentPage);
}
//super.fling(velocityX);
}
}
2.布局文件Activity_main.xml：
代码如下:
3.IDrawerPresenter接口(IDrawerPresenter.java)：
代码如下:
public interface IDrawerPresenter {
IDrawerPresenter getInstance();
void dispatchEvent(int totalPages, int currentPage);
}
4.DrawerItem
代码如下:
5.MainActivity.java
(1)实现IDrawerPresenter接口，在HorizontalScrollView里通过IDrawerPresenter接口来返回当前页，从而更新pageindicator。
代码如下:
@Override
public IDrawerPresenter getInstance() {
return this;
}
@Override
public void dispatchEvent(int totalPages, int currentPage) {
Log.v(TAG, "~~~~dispatchEvent currentPage:" + currentPage);
Message msg = Message.obtain();
msg.what = MSG_DRAWER_UPDATE_PAGE_LAYOUT;
msg.arg1 = totalPages;
msg.arg2 = currentPage;
handler.sendMessage(msg);
}
(2)PageItemImageView和page indicator的更新
PageItemImageView显示normal的page indicator，之后再将当前页的图片换成selected。
代码如下:
protected class PageItemImageView extends ImageView {
public PageItemImageView(Context context) {
super(context);
Bitmap bitmap = BitmapFactory.decodeResource(getResources(),
R.drawable.icon_page_normal);
this.setImageBitmap(bitmap);
}
}
public void updateDrawerPageLayout(int total_pages, int sel_page) {
Log.e(TAG, "~~~updateBooksPageLayout total_pages:"+total_pages+",sel_page:"+sel_page);
layout_pagenumber.removeAllViews();
if (total_pages = total_pages){
Log.e(TAG, "total_pages or sel_page is outofrange.");
return;
}
for (int i = 0;i< total_pages;i++){
if (i != 0){
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.setMargins(5, 0, 0, 0);
layout_pagenumber.addView(new PageItemImageView(this), params);
} else {
layout_pagenumber.addView(new PageItemImageView(this));
}
}
PageItemImageView selItem = (PageItemImageView) layout_pagenumber.getChildAt(sel_page);
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.icon_page_selected);
selItem.setImageBitmap(bitmap);
}
(3)DrawerListAdapter
代码如下:
private class DrawerListAdapter extends BaseAdapter {
private final String TAG = "MyListAdapter";
private LayoutInflater mInflater;
private LinearLayout layout_item;
private TextView tvTitle;
private ImageView ivIcon;
private final Context context;
private int colWid;
private int colHei;
public DrawerListAdapter(Context context, int colWid, int colHei) {
this.context = context;
this.colWid = colWid;
this.colHei = colHei;
mInflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
public int getCount() {
return drawerItemList.size();
}
public Object getItem(int position) {
return drawerItemList.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
DrawerItem item = drawerItemList.get(position);
if (convertView == null) {
convertView = mInflater.inflate(R.layout.drawer_item, null);
layout_item = (LinearLayout) convertView
.findViewById(R.id.layout_item);
ivIcon = (ImageView) convertView.findViewById(R.id.ivIcon);
tvTitle = (TextView) convertView.findViewById(R.id.tvTitle);
if (colHei != 0 && colWid != 0) {
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
colWid, colHei - 30);
ivIcon.setLayoutParams(params);
}
convertView.setTag(layout_item);
} else {
layout_item = (LinearLayout) convertView.getTag();
}
ivIcon.setImageResource(R.drawable.ic_launcher);
tvTitle.setText(String.valueOf(position));
return convertView;
}
}
(4)DrawerItemClickListener:
实现OnItemClickListener。
(5) updateDrawerLayout
获得data的size后，可以算出列数来得到固定行。
intnumCols = (drawerItemList.size() - 1) / 2 + 1
再算出gridview的width。因每页可显示2列，最后一页可能右侧没有，为了翻页顺滑，可以给gridview增加一列空白。
intgridViewWid = numCols * colWid + (numCols + 1) * spaceing;
if(numCols % 2 == 1){
gridViewWid+= colWid + spaceing;
}
代码如下:
public void updateDrawerLayout() {
if ((drawerItemList == null) || (drawerItemList.size() == 0)) {
Log.d(TAG, "itemList is null or empty");
return;
}
if (!hasMeasured){
Log.d(TAG, "hasMeasured is false");
return;
}
int scrollWid = hscrollview.getWidth();
int scrollHei = hscrollview.getHeight();
if (scrollWid