ExpandableListView小图标替换

ExpandableListView的小图标有个状态，一个是不点击的情况，一个是点击后展开的情况，用xml配置如下：

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
       <item android:state_expanded="true" android:drawable="@drawable/narrow_select" />
       <item android:drawable="@drawable/narrow" />
</selector>

Java的代码如下：

ExpandableListView listView = getExpandableListView();
listView.setGroupIndicator(this.getResources().getDrawable(R.drawable.group_icon_selector));

注意：不知道为什么，使用自定义的GroupIndicator会发生图片被拉伸的现象，为了解决这个问题需要定义一个长度为groups.length的boolean数组：

private boolean[] isOpen=new boolean[groups.length];

然后重写OnGroupCollapseListener和OnGroupExpandListener用于修改当前group的状态：

expandableListView.setOnGroupCollapseListener(onGroupCollapseListener);
expandableListView.setOnGroupExpandListener(onGroupExpandListener);
expandableListView.setGroupIndicator(null);//不要自带的了！！！
OnGroupCollapseListener onGroupCollapseListener=new OnGroupCollapseListener(){

			@Override
			public void onGroupCollapse(int groupPosition) {
				// TODO Auto-generated method stub
				isOpen[groupPosition]=false;
			}
			
		};
		
OnGroupExpandListener onGroupExpandListener=new OnGroupExpandListener(){

			@Override
			public void onGroupExpand(int groupPosition) {
				// TODO Auto-generated method stub
				isOpen[groupPosition]=true;
			}
			
		};

最后在getGroupView()中应用，代码片段如下：

@Override
public View getGroupView(int groupPosition, boolean isExpanded,
					View convertView, ViewGroup parent) {
				// TODO Auto-generated method stub
				TextView textView=null;
				if(convertView==null){
					textView=new TextView(mContext);
					AbsListView.LayoutParams lp = new AbsListView.LayoutParams(  
		                    ViewGroup.LayoutParams.FILL_PARENT, 50);  
		            textView.setLayoutParams(lp);
		            textView.setGravity(Gravity.CENTER);
		            textView.setPadding(10, 0, 0, 0);
		            textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 16.0f);
		            textView.setTextColor(0xFFC6B39C);
		            textView.setBackgroundResource(R.drawable.bg_tv);//bg_tv_expand
		            convertView=textView;
				}else{
					textView=(TextView)convertView;
				}
				//为了处理图标被拉伸的问题！这里采用偷懒的办法让textView傍边产生一个图标，如果GroupView只是一个TextView的话，推荐这样做！
				if(isOpen[groupPosition]){
					Drawable leftDrawable= resources.getDrawable(R.drawable.arrow_down_on);
	            	leftDrawable.setBounds(0, 0, leftDrawable.getMinimumWidth(), leftDrawable.getMinimumHeight());
	            	textView.setCompoundDrawables(leftDrawable, null, null, null);
				}else{
					Drawable leftDrawable= resources.getDrawable(R.drawable.arrow_right_off);
					leftDrawable.setBounds(0, 0, leftDrawable.getMinimumWidth(), leftDrawable.getMinimumHeight());
					textView.setCompoundDrawables(leftDrawable, null, null, null);
				}
				textView.setText(((Market)getGroup(groupPosition)).market);
	            return textView;
}

over！

Android版手风琴(ExpandableListView)

创新源于模仿之四：增强的ExpandableListView

android api里的例子：

import android.app.ExpandableListActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.Gravity;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.ContextMenu.ContextMenuInfo;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ExpandableListView.ExpandableListContextMenuInfo;

import com.example.android.apis.R;

/**
 * Demonstrates expandable lists using a custom {@link ExpandableListAdapter}
 * from {@link BaseExpandableListAdapter}.
 */
public class ExpandableList1 extends ExpandableListActivity {

    ExpandableListAdapter mAdapter;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Set up our adapter
        mAdapter = new MyExpandableListAdapter();
        setListAdapter(mAdapter);
        registerForContextMenu(getExpandableListView());
    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
        menu.setHeaderTitle("Sample menu");
        menu.add(0, 0, 0, R.string.expandable_list_sample_action);
    }
    
    @Override
    public boolean onContextItemSelected(MenuItem item) {
        ExpandableListContextMenuInfo info = (ExpandableListContextMenuInfo) item.getMenuInfo();

        String title = ((TextView) info.targetView).getText().toString();
        
        int type = ExpandableListView.getPackedPositionType(info.packedPosition);
        if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) {
            int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition); 
            int childPos = ExpandableListView.getPackedPositionChild(info.packedPosition); 
            Toast.makeText(this, title + ": Child " + childPos + " clicked in group " + groupPos,
                    Toast.LENGTH_SHORT).show();
            return true;
        } else if (type == ExpandableListView.PACKED_POSITION_TYPE_GROUP) {
            int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition); 
            Toast.makeText(this, title + ": Group " + groupPos + " clicked", Toast.LENGTH_SHORT).show();
            return true;
        }
        
        return false;
    }

    /**
     * A simple adapter which maintains an ArrayList of photo resource Ids. 
     * Each photo is displayed as an image. This adapter supports clearing the
     * list of photos and adding a new photo.
     *
     */
    public class MyExpandableListAdapter extends BaseExpandableListAdapter {
        // Sample data set.  children[i] contains the children (String[]) for groups[i].
        private String[] groups = { "People Names", "Dog Names", "Cat Names", "Fish Names" };
        private String[][] children = {
                { "Arnold", "Barry", "Chuck", "David" },
                { "Ace", "Bandit", "Cha-Cha", "Deuce" },
                { "Fluffy", "Snuggles" },
                { "Goldy", "Bubbles" }
        };
        
        public Object getChild(int groupPosition, int childPosition) {
            return children[groupPosition][childPosition];
        }

        public long getChildId(int groupPosition, int childPosition) {
            return childPosition;
        }

        public int getChildrenCount(int groupPosition) {
            return children[groupPosition].length;
        }

        public TextView getGenericView() {
            // Layout parameters for the ExpandableListView
            AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
                    ViewGroup.LayoutParams.MATCH_PARENT, 64);

            TextView textView = new TextView(ExpandableList1.this);
            textView.setLayoutParams(lp);
            // Center the text vertically
            textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
            // Set the text starting position
            textView.setPadding(36, 0, 0, 0);
            return textView;
        }
        
        public View getChildView(int groupPosition, int childPosition, boolean isLastChild,
                View convertView, ViewGroup parent) {
            TextView textView = getGenericView();
            textView.setText(getChild(groupPosition, childPosition).toString());
            return textView;
        }

        public Object getGroup(int groupPosition) {
            return groups[groupPosition];
        }

        public int getGroupCount() {
            return groups.length;
        }

        public long getGroupId(int groupPosition) {
            return groupPosition;
        }

        public View getGroupView(int groupPosition, boolean isExpanded, View convertView,
                ViewGroup parent) {
            TextView textView = getGenericView();
            textView.setText(getGroup(groupPosition).toString());
            return textView;
        }

        public boolean isChildSelectable(int groupPosition, int childPosition) {
            return true;
        }

        public boolean hasStableIds() {
            return true;
        }

    }
}

Android UI 之实现多级列表TreeView
http://blog.csdn.net/carrey1989/article/details/10227165