ExpandListViewActivity.java

package com.mcxtzhang.github.expand;

import android.database.DataSetObserver;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

import com.mcxtzhang.github.R;

public class ExpandListViewActivity extends AppCompatActivity {

    ExpandableListView mExpandableListView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_expand_list_view);
        mExpandableListView = (ExpandableListView) findViewById(R.id.expandListView);
        MyExpandableListAdapter adapter = new MyExpandableListAdapter();
        mExpandableListView.setAdapter(adapter);
    }


    class MyExpandableListAdapter implements ExpandableListAdapter {
        int[] logos = new int[]{
                R.mipmap.ic_launcher,
                R.mipmap.ic_launcher, R.mipmap.ic_launcher, R.mipmap.ic_launcher
        };
        private String[] armTypes = new String[]{
                "WORD", "EXCEL", "EMAIL", "PPT"
        };
        private String[][] arms = new String[][]{
                {"文档编辑", "文档排版", "文档处理", "文档打印"},
                {"表格编辑", "表格排版", "表格处理", "表格打印"},
                {"收发邮件", "管理邮箱", "登录登出", "注册绑定"},
                {"演示编辑", "演示排版", "演示处理", "演示打印"},
        };

        @Override
        public void registerDataSetObserver(DataSetObserver observer) {

        }

        @Override
        public void unregisterDataSetObserver(DataSetObserver observer) {

        }

        @Override
        public int getGroupCount() {
            return armTypes.length;
        }

        @Override
        public int getChildrenCount(int groupPosition) {
            return arms[groupPosition].length;
        }

        @Override
        public Object getGroup(int groupPosition) {
            return armTypes[groupPosition];
        }

        @Override
        public Object getChild(int groupPosition, int childPosition) {
            return arms[groupPosition][childPosition];
        }

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

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

        @Override
        public boolean hasStableIds() {
            return true;
        }

        @Override
        public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
            Log.d("TAG", "getGroupView() called with: groupPosition = [" + groupPosition + "], isExpanded = [" + isExpanded + "], convertView = [" + convertView + "], parent = [" + parent + "]");
            LinearLayout ll = new LinearLayout(ExpandListViewActivity.this);
            ll.setOrientation(LinearLayout.HORIZONTAL);
            ImageView logo = new ImageView(ExpandListViewActivity.this);
            logo.setImageResource(logos[groupPosition]);
            logo.setPadding(36, 15, 0, 0);
            ll.addView(logo);
            TextView textView = getTextView();
            textView.setText(getGroup(groupPosition).toString());
            textView.setPadding(10, 0, 0, 0);
            ll.addView(textView);
            return ll;
        }

        @Override
        public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
            Log.d("TAG", "getChildView() called with: groupPosition = [" + groupPosition + "], childPosition = [" + childPosition + "], isLastChild = [" + isLastChild + "], convertView = [" + convertView + "], parent = [" + parent + "]");
            TextView textView = getTextView();
            textView.setText(getChild(groupPosition, childPosition).toString());
            return textView;
        }

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

        @Override
        public boolean areAllItemsEnabled() {
            return false;
        }

        @Override
        public boolean isEmpty() {
            return false;
        }

        @Override
        public void onGroupExpanded(int groupPosition) {

        }

        @Override
        public void onGroupCollapsed(int groupPosition) {

        }

        @Override
        public long getCombinedChildId(long groupId, long childId) {
            return 0;
        }

        @Override
        public long getCombinedGroupId(long groupId) {
            return 0;
        }

        private TextView getTextView() {
            AbsListView.LayoutParams lp = new AbsListView.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, 300);
            TextView textView = new TextView(ExpandListViewActivity.this);
            textView.setLayoutParams(lp);
            textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
            textView.setPadding(36, 0, 0, 0);
            textView.setTextSize(20);
            return textView;
        }
    }
}