View--ExpandableListview(二级下拉菜单)

[android]代码库

1.MainActivity.java

package com.example.acer.myapplication;

    import android.graphics.Color;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseExpandableListAdapter;
    import android.widget.ExpandableListAdapter;
    import android.widget.ExpandableListView;
    import android.widget.LinearLayout;
    import android.widget.TextView;

    public class MainActivity extends AppCompatActivity{

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

            final ExpandableListAdapter adapter = new BaseExpandableListAdapter() {

                //设置组视图的显示文字
                private String[] country = new String[] { "魏", "蜀" };
                //子视图显示文字
                private String[][] name = new String[][] {
                        { "夏侯惇", "甄姬", "许褚" },
                        { "马超", "张飞", "刘备" },
                };
                
                //重写ExpandableListAdapter中的各个方法
                @Override
                public int getGroupCount() {
                    return country.length;
                }

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

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

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

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

                @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) {
                    LinearLayout ll = new LinearLayout(MainActivity.this);
                    TextView textView = new TextView(MainActivity.this);
                    textView.setText(getGroup(groupPosition).toString());
                    textView.setTextSize(30);
                    textView.setPadding(80,0,0,0);
                    ll.addView(textView);
                    return ll;
                }

                @Override
                public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
                    LinearLayout ll = new LinearLayout(MainActivity.this);
                    TextView textView = new TextView(MainActivity.this);
                    textView.setText(getChild(groupPosition, childPosition).toString());
                    textView.setTextColor(Color.BLUE);
                    textView.setTextSize(20);
                    ll.addView(textView);
                    return ll;
                }

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

            ExpandableListView expandableListView = (ExpandableListView) findViewById(R.id.list);
            expandableListView.setAdapter(adapter);
        }
    }

2.activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical" >

        <ExpandableListView
            android:id="@+id/list"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            >
        </ExpandableListView>
    </LinearLayout>