我已将BaseExpandableListAdapter
用于我的可扩展列表视图。它一次又一次地调用getGroupCount()
,这会降低应用程序性能。
这是我的代码:
public class ExpandableCustomAdapter extends BaseExpandableListAdapter {
private LayoutInflater inflater;
ArrayList<MenuItem> menuItem;
Context context;
private Map<String, ArrayList<MenuItem>> parent;
public ExpandableCustomAdapter(Context context, Map<String, ArrayList<MenuItem>> mParent) {
parent = mParent;
inflater = LayoutInflater.from(context);
this.context = context;
}
@Override
// counts the number of group/parent items so the list knows how many
// times calls getGroupView() method
public int getGroupCount() {
int size = parent.size();
return size;
}
@Override
// counts the number of children items so the list knows how many times
// calls getChildView() method
public int getChildrenCount(int i) {
List<String> copyOfKeys = new ArrayList<String>(parent.keySet());
menuItem = parent.get(copyOfKeys.get(i));
return menuItem.size();
}
@Override
public Object getChild(int groupPosition, int childPosition) {
List<String> copyOfKeys = new ArrayList<String>(parent.keySet());
menuItem = parent.get(copyOfKeys.get(groupPosition));
Object obj = menuItem.get(childPosition);
return obj;
}
@Override
// in this method you must set the text to see the parent/group on the
// list
public View getGroupView(int i, boolean b, View view, ViewGroup viewGroup) {
ParentViewHolder holder;
System.out.println("getview:" + i);
if (view == null)
{
holder = new ParentViewHolder();
LayoutInflater infalInflater = (LayoutInflater) instance.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = infalInflater.inflate(
R.layout.bannerlayoutparentinflater, null);
holder.backgroundRelative = (RelativeLayout) view
.findViewById(R.id.mainlayoutparent);
view.setTag(holder);
}
else
{
holder = (ParentViewHolder) view.getTag();
}
// Beverages_Cocktails_banner
List<String> copyOfKeys = new ArrayList<String>(parent.keySet());
menuItem = parent.get(copyOfKeys.get(i));
String course = menuItem.get(0).course;
Drawable background = new BitmapDrawable(getResources(), ImageList
.getInstance().getImageBitmap(value);
holder.backgroundRelative.setBackground(background);
// set Image indicator
holder.indicator = (ImageView) view.findViewById(R.id.imageView1);
if (b)
{
holder.indicator.setRotation(180);
}
else
{
Bitmap menuIndBitmapicatorBitmap = ImageList.getInstance()
.getImageBitmap(ImageNames.SECTION_HEADER_ARROW_IMAGE);
holder.indicator.setImageBitmap(menuIndBitmapicatorBitmap);
holder.indicator.setRotation(360);
}
// return the entire view
return view;
}
@Override
// in this method you must set the text to see the children on the list
public View getChildView(int i, int i1, boolean b, View view,
ViewGroup viewGroup) {
ChildViewHolder childHolder;
if (view == null) {
childHolder = new ChildViewHolder();
inflater = LayoutInflater.from(context);
LayoutInflater infalInflater = (LayoutInflater) instance.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = infalInflater.inflate(
R.layout.bannerlayoutchildinflater, null);
childHolder.backgroundRelativeChild = (RelativeLayout) view
.findViewById(R.id.mainlayoutchild);
view.setTag(childHolder);
}
else
{
childHolder = (ChildViewHolder) view.getTag();
}
//childHolder.backgroundRelativeChild.removeAllViews();
List<String> copyOfKeys = new ArrayList<String>(parent.keySet());
menuItem = new ArrayList<MenuItem>();
menuItem = parent.get(copyOfKeys.get(i));
// removeAllViews();
CategoryCourseMenuList menuList1 = new CategoryCourseMenuList(
instance, null, 0, menuItem);
MenuItem menu=menuItem.get(i1);
menuList1.addLayoutMenu(menu);
// menuList1.setCourseMenuList(menuItem);
LayoutParams menuListParams = new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
menuListParams.topMargin = Utils.getPixelValue(2);
menuListParams.bottomMargin = Utils.getPixelValue(2);
childHolder.backgroundRelativeChild.addView(menuList1, menuListParams);
Animation animation = AnimationUtils.loadAnimation(context, R.anim.list_animation);
// view.startAnimation(animation);
// animation = null;
// return the entire view
return view;
}
@Override
public void registerDataSetObserver(DataSetObserver observer) {
/* used to make the notifyDataSetChanged() method work */
super.registerDataSetObserver(observer);
}
@Override
public Object getGroup(int groupPosition) {
Object obj = parent.get(groupPosition);
return obj;
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
任何想法?