如何在以下方案中使用可扩展列表视图

Question

我正在创建一个应用程序，它为管理员用户提供了不同的屏幕，为普通用户提供了不同的屏幕。管理员登录时，将显示包含可扩展列表视图的屏幕。可扩展列表视图标头是一个字符串数组。子项是从数据库获取的值列表。现在，请告诉我如何在我的案例中使用可扩展列表视图？由于我有不同的子视图列表，我应该使用多个适配器吗？当我尝试使用ExpandableListAdapter时，它告诉我实现了8个方法，如果是的话，我应该使用所有这些方法吗？以下代码片段是我现在拥有的：

这是我的Admin Activity类：

import android.content.Context;
import android.database.Cursor;
import android.graphics.Color;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.SimpleCursorTreeAdapter;

import java.util.List;


public class AdminActivity extends AppCompatActivity {

    Toolbar toolbar;
    ExpandableListAdapter listAdapter;
    List<String> titleText;
   SQLiteDataBaseAdapter db;

    ExpandableListView login, android, ios, testing, java, dotNet, os, hr, others;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_admin);

        toolbar = (Toolbar) findViewById(R.id.appBar);
        toolbar.setTitle(" Admin Screen");
        toolbar.setTitleTextColor(Color.WHITE);

        login = (ExpandableListView) findViewById(R.id.expandableListViewLogin);
        android = (ExpandableListView) findViewById(R.id.expandableListViewAndroid);
        ios = (ExpandableListView) findViewById(R.id.expandableListViewIos);
        testing = (ExpandableListView) findViewById(R.id.expandableListViewTesting);
        java = (ExpandableListView) findViewById(R.id.expandableListViewJava);
        dotNet = (ExpandableListView) findViewById(R.id.expandableListViewDotNet);
        os = (ExpandableListView) findViewById(R.id.expandableListViewOS);
        hr = (ExpandableListView) findViewById(R.id.expandableListViewHR);
        others = (ExpandableListView) findViewById(R.id.expandableListViewOthers);



// Lsit of values for header. One for each list view.
        titleText.add("User Id Authentication");
        titleText.add("Android Posts Authentication");
        titleText.add("iOS Posts Authentication");
        titleText.add("Testing Posts Authentication");
        titleText.add("Java Posts Authentication");
        titleText.add("Dot Net Posts Authentication");
        titleText.add("OS Posts Authentication");
        titleText.add("HR Posts Authentication");
        titleText.add("Others Posts Authentication");




        SQLiteDataBaseAdapter db = new SQLiteDataBaseAdapter(this);
        List<String> childData =  db.getAndroidList();


        //setting the list adapter
        listAdapter = new ExpandableListAdapter(this, titleText, childData);// this tells to implement some 8 methods, should I implement??

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_admin, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

}

我在一个屏幕上有如此多的可扩展列表视图数组列表用于每个可扩展列表视图的标题，子项将再次来自数据库的值列表。请告诉我如何在我的案例中使用可扩展列表视图。我是android的新手，这是我第一次使用Expandable List View。欢迎所有建议。提前谢谢。

Answer 1

您可以在以下链接中找到可扩展列表视图的优秀教程。

http://www.androidhive.info/2013/07/android-expandable-list-view-tutorial/

在将其作为可扩展列表视图适配器的输入提供之前，您可以从字符串列表中删除不需要的标题和子项（基于管理员/用户）

Answer 2

你应该设置适配器：

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

    toolbar = (Toolbar) findViewById(R.id.appBar);
    toolbar.setTitle(" Admin Screen");
    toolbar.setTitleTextColor(Color.WHITE);

    login = (ExpandableListView) findViewById(R.id.expandableListViewLogin);
    android = (ExpandableListView) findViewById(R.id.expandableListViewAndroid);
    ios = (ExpandableListView) findViewById(R.id.expandableListViewIos);
    testing = (ExpandableListView) findViewById(R.id.expandableListViewTesting);
    java = (ExpandableListView) findViewById(R.id.expandableListViewJava);
    dotNet = (ExpandableListView) findViewById(R.id.expandableListViewDotNet);
    os = (ExpandableListView) findViewById(R.id.expandableListViewOS);
    hr = (ExpandableListView) findViewById(R.id.expandableListViewHR);
    others = (ExpandableListView) findViewById(R.id.expandableListViewOthers);
    titleText.add("User Id Authentication");
    titleText.add("Android Posts Authentication");
    titleText.add("iOS Posts Authentication");
    titleText.add("Testing Posts Authentication");
    titleText.add("Java Posts Authentication");
    titleText.add("Dot Net Posts Authentication");
    titleText.add("OS Posts Authentication");
    titleText.add("HR Posts Authentication");
    titleText.add("Others Posts Authentication");
    SQLiteDataBaseAdapter db = new SQLiteDataBaseAdapter(this);
    List<String> childData =  db.getAndroidList();
    //setting the list adapter
    listAdapter = new ExpandableListAdapter(this, titleText, childData);
    ExpandableListView listView = (ExpandableListView) findViewById(R.id.listView);
    listView.setAdapter(listAdapter);

}

Answer 3

**Its Working**

package com.keshav.myexpandablelistviewexampleworkinginactivity;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.ExpandableListView.OnGroupClickListener;
import android.widget.ExpandableListView.OnGroupCollapseListener;
import android.widget.ExpandableListView.OnGroupExpandListener;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class MainActivity extends Activity {

    ExpandableListAdapter listAdapter;
    ExpandableListView expListView;
    List<String> listDataHeader;
    HashMap<String, List<String>> listDataChild;

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

        // tODO get the listview
        expListView = (ExpandableListView) findViewById(R.id.lvExp);

        // TODO preparing list data
        prepareListData();

        listAdapter = new ExpandableListAdapter(this, listDataHeader, listDataChild);

        // setting list adapter
        expListView.setAdapter(listAdapter);

        // Listview Group click listener
        expListView.setOnGroupClickListener(new OnGroupClickListener() {

            @Override
            public boolean onGroupClick(ExpandableListView parent, View v,
                                        int groupPosition, long id) {
                Toast.makeText(getApplicationContext(),
                        "Group Clicked " + listDataHeader.get(groupPosition),
                        Toast.LENGTH_SHORT).show();
                return false;
            }

        });

        // Listview Group expanded listener
        expListView.setOnGroupExpandListener(new OnGroupExpandListener() {

            // TODO Colapse Here Using this... in android
            int previousGroup = -1;
            boolean flag = false;

            @Override
            public void onGroupExpand(int groupPosition) {

                Log.e("keshav", "onGroupClick is -> " + groupPosition);

                Toast.makeText(getApplicationContext(),
                        listDataHeader.get(groupPosition) + " Expanded",
                        Toast.LENGTH_SHORT).show();

                if (groupPosition != previousGroup && flag) {
                    expListView.collapseGroup(previousGroup);
                }
                previousGroup = groupPosition;

                flag = true;

            }
        });


        // Listview Group collasped listener
        expListView.setOnGroupCollapseListener(new OnGroupCollapseListener() {

            @Override
            public void onGroupCollapse(int groupPosition) {
                Toast.makeText(getApplicationContext(),
                        listDataHeader.get(groupPosition) + " Collapsed",
                        Toast.LENGTH_SHORT).show();

            }
        });


        // Todo Listview on child click listener
        expListView.setOnChildClickListener(new OnChildClickListener() {

            @Override
            public boolean onChildClick(ExpandableListView parent, View v,
                                        int groupPosition, int childPosition, long id) {
                // TODO Auto-generated method stub
                Toast.makeText(
                        getApplicationContext(),
                        listDataHeader.get(groupPosition)
                                + " : "
                                + listDataChild.get(
                                listDataHeader.get(groupPosition)).get(
                                childPosition), Toast.LENGTH_SHORT)
                        .show();
                return false;
            }
        });
    }

    /*
     * Preparing the list data
     */
    private void prepareListData() {
        listDataHeader = new ArrayList<String>();
        listDataChild = new HashMap<String, List<String>>();

        // Adding child data
        listDataHeader.add("Months");
        listDataHeader.add("Top 250");
        listDataHeader.add("Now Showing");
        listDataHeader.add("Coming Soon..");


        // Adding child data
        List<String> weeks = new ArrayList<String>();
        weeks.add("Sunday");
        weeks.add("Monday");
        weeks.add("Tuesday");
        weeks.add("Wednesday");
        weeks.add("Thursday");
        weeks.add("Friday");
        weeks.add("Saturday");


        // Adding child data
        List<String> top250 = new ArrayList<String>();
        top250.add("Om Shanti Om");
        top250.add("Badshah");
        top250.add("Bahubali Part 1");
        top250.add("Carry on Jatta");
        top250.add("Sholey");
        top250.add("Mard");
        top250.add("Dewwar");


        List<String> nowShowing = new ArrayList<String>();
        nowShowing.add("Bahubali");
        nowShowing.add("Kabali");
        nowShowing.add("Luckky Di Unlukky Story");
        nowShowing.add("Sachin Billions Dream");
        nowShowing.add("Red 2");

        List<String> comingSoon = new ArrayList<String>();
        comingSoon.add("Tubelight ");
        comingSoon.add("Bahubali 3 2018");
        comingSoon.add("Dhoom 4");
        comingSoon.add("Hindi Medium");

        listDataChild.put(listDataHeader.get(0), weeks);
        listDataChild.put(listDataHeader.get(1), top250); // Header, Child data
        listDataChild.put(listDataHeader.get(2), nowShowing);
        listDataChild.put(listDataHeader.get(3), comingSoon);
    }
}



package com.keshav.myexpandablelistviewexampleworkinginactivity;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.ExpandableListView.OnGroupClickListener;
import android.widget.ExpandableListView.OnGroupCollapseListener;
import android.widget.ExpandableListView.OnGroupExpandListener;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class MainActivity extends Activity {

    ExpandableListAdapter listAdapter;
    ExpandableListView expListView;
    List<String> listDataHeader;
    HashMap<String, List<String>> listDataChild;

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

        // tODO get the listview
        expListView = (ExpandableListView) findViewById(R.id.lvExp);

        // TODO preparing list data
        prepareListData();

        listAdapter = new ExpandableListAdapter(this, listDataHeader, listDataChild);

        // setting list adapter
        expListView.setAdapter(listAdapter);

        // Listview Group click listener
        expListView.setOnGroupClickListener(new OnGroupClickListener() {

            @Override
            public boolean onGroupClick(ExpandableListView parent, View v,
                                        int groupPosition, long id) {
                Toast.makeText(getApplicationContext(),
                        "Group Clicked " + listDataHeader.get(groupPosition),
                        Toast.LENGTH_SHORT).show();
                return false;
            }

        });

        // Listview Group expanded listener
        expListView.setOnGroupExpandListener(new OnGroupExpandListener() {

            // TODO Colapse Here Using this... in android
            int previousGroup = -1;
            boolean flag = false;

            @Override
            public void onGroupExpand(int groupPosition) {

                Log.e("keshav", "onGroupClick is -> " + groupPosition);

                Toast.makeText(getApplicationContext(),
                        listDataHeader.get(groupPosition) + " Expanded",
                        Toast.LENGTH_SHORT).show();

                if (groupPosition != previousGroup && flag) {
                    expListView.collapseGroup(previousGroup);
                }
                previousGroup = groupPosition;

                flag = true;

            }
        });


        // Listview Group collasped listener
        expListView.setOnGroupCollapseListener(new OnGroupCollapseListener() {

            @Override
            public void onGroupCollapse(int groupPosition) {
                Toast.makeText(getApplicationContext(),
                        listDataHeader.get(groupPosition) + " Collapsed",
                        Toast.LENGTH_SHORT).show();

            }
        });


        // Todo Listview on child click listener
        expListView.setOnChildClickListener(new OnChildClickListener() {

            @Override
            public boolean onChildClick(ExpandableListView parent, View v,
                                        int groupPosition, int childPosition, long id) {
                // TODO Auto-generated method stub
                Toast.makeText(
                        getApplicationContext(),
                        listDataHeader.get(groupPosition)
                                + " : "
                                + listDataChild.get(
                                listDataHeader.get(groupPosition)).get(
                                childPosition), Toast.LENGTH_SHORT)
                        .show();
                return false;
            }
        });
    }

    /*
     * Preparing the list data
     */
    private void prepareListData() {
        listDataHeader = new ArrayList<String>();
        listDataChild = new HashMap<String, List<String>>();

        // Adding child data
        listDataHeader.add("Months");
        listDataHeader.add("Top 250");
        listDataHeader.add("Now Showing");
        listDataHeader.add("Coming Soon..");


        // Adding child data
        List<String> weeks = new ArrayList<String>();
        weeks.add("Sunday");
        weeks.add("Monday");
        weeks.add("Tuesday");
        weeks.add("Wednesday");
        weeks.add("Thursday");
        weeks.add("Friday");
        weeks.add("Saturday");


        // Adding child data
        List<String> top250 = new ArrayList<String>();
        top250.add("Om Shanti Om");
        top250.add("Badshah");
        top250.add("Bahubali Part 1");
        top250.add("Carry on Jatta");
        top250.add("Sholey");
        top250.add("Mard");
        top250.add("Dewwar");


        List<String> nowShowing = new ArrayList<String>();
        nowShowing.add("Bahubali");
        nowShowing.add("Kabali");
        nowShowing.add("Luckky Di Unlukky Story");
        nowShowing.add("Sachin Billions Dream");
        nowShowing.add("Red 2");

        List<String> comingSoon = new ArrayList<String>();
        comingSoon.add("Tubelight ");
        comingSoon.add("Bahubali 3 2018");
        comingSoon.add("Dhoom 4");
        comingSoon.add("Hindi Medium");

        listDataChild.put(listDataHeader.get(0), weeks);
        listDataChild.put(listDataHeader.get(1), top250); // Header, Child data
        listDataChild.put(listDataHeader.get(2), nowShowing);
        listDataChild.put(listDataHeader.get(3), comingSoon);
    }
}

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"
    android:background="#f4f4f4" >

            <ExpandableListView
                android:id="@+id/lvExp"
                android:layout_height="match_parent"
                android:layout_width="match_parent"
                android:cacheColorHint="#00000000"/>   

</LinearLayout>

list_group.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="wrap_content"
    android:orientation="vertical"
    android:padding="8dp" 
    android:background="#000000">


    <TextView
        android:id="@+id/lblListHeader"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"
        android:textSize="17dp"
        android:textColor="#f9f93d" />

</LinearLayout>


list_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="55dip"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/lblListItem"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:textSize="17dip"
        android:paddingTop="5dp"
        android:paddingBottom="5dp"
        android:textColor="#000000"
        android:paddingLeft="?android:attr/expandableListPreferredChildPaddingLeft" />

</LinearLayout>