Question

我在android中创建了一个ExpandableListView。我有一些类别有更多的子类别。而其他没有子类别。如果图标没有子类别，我怎么能删除它？

E.g。我有一个类别如Home，sarees等。在Home中，没有子类别，所以我需要删除可扩展的展开图标。

这是content_home.xml ExpandableListView

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.domore.onlineangelnx.Home"
    tools:showIn="@layout/activity_home">

    <FrameLayout
        android:id="@+id/frame_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <!-- Listview to display slider menu -->
    <ExpandableListView
        android:id="@+id/list_slidermenu"
        android:layout_width="240dp"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:divider="@color/list_divider"
        android:dividerHeight="1dp"
        android:listSelector="@drawable/list_selector"
        android:background="@color/list_background"/>
    <!--android:choiceMode="singleChoice"-->
</android.support.v4.widget.DrawerLayout>

以下是我的drawable_list_item.xml，TextView显示ExpandableListView标题

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

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"
        android:minHeight="?android:attr/listPreferredItemHeightSmall"
        android:textAppearance="?android:attr/textAppearanceListItemSmall"
        android:textColor="@color/list_item_title"
        android:gravity="center_vertical" />

</LinearLayout>

这是我的ExpandableListViewAdapter，用于计算项目及其子项目

package adapter;

import android.content.Context;
import android.graphics.Typeface;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.TextView;

import com.domore.onlineangelnx.R;

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

/**
 * Created by MY WORLD on 10/27/2015.
 */
public class ExpandableListAdapter extends BaseExpandableListAdapter {

    Context context;
    List<String> listDataHeader;
    HashMap<String,List<String>> listDataChild;


    public ExpandableListAdapter(Context context, List<String> listDataHeader, HashMap<String, List<String>> listDataChild){
        this.context=context;
        this.listDataHeader=listDataHeader;
        this.listDataChild=listDataChild;
    }

    @Override
    public Object getChild(int i, int i1) {
        return this.listDataChild.get(this.listDataHeader.get(i)).get(i1);
    }

    @Override
    public int getGroupCount() {
        return this.listDataHeader.size();
    }

    @Override
    public int getChildrenCount(int i) {
        return this.listDataChild.get(this.listDataHeader.get(i)).size();
    }

    @Override
    public Object getGroup(int i) {
        return this.listDataHeader.get(i);
    }

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

    @Override
    public long getChildId(int i, int i1) {
        return i1;
    }

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

    @Override
    public View getGroupView(int i, boolean b, View view, ViewGroup viewGroup) {

        String headerTitle=(String)getGroup(i);

        if(view==null){
            LayoutInflater inflater=(LayoutInflater)this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            view=inflater.inflate(R.layout.drawer_list_item,null);
        }
        TextView lblListHeader=(TextView)view.findViewById(R.id.title);
        lblListHeader.setTypeface(null, Typeface.BOLD);
        lblListHeader.setText(headerTitle);
        return view;
    }

    @Override
    public View getChildView(int i, int i1, boolean b, View view, ViewGroup viewGroup) {
        final String childText=(String)getChild(i,i1);

        if(view==null){
            LayoutInflater inflater=(LayoutInflater)this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            view=inflater.inflate(R.layout.child_tems,null);
        }
        TextView txtListChild=(TextView)view.findViewById(R.id.lblListItem);
        txtListChild.setText(childText);
        return view;
    }

    @Override
    public boolean isChildSelectable(int i, int i1) {
        return true;
    }
}

这是我的Home.java（MainActivity.java），它设置List<String>和HashMap<String,List<String>>的参数

package com.domore.onlineangelnx;

import android.content.res.Configuration;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ExpandableListView;
import android.widget.Toast;

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

import MainFragments.HomeFragment;
import MainFragments.SareesFragment;
import adapter.ExpandableListAdapter;

public class Home extends AppCompatActivity {

    private DrawerLayout mDrawerLayout;
    private ActionBarDrawerToggle mDrawerToggle;
    private ExpandableListAdapter adapter=null;

    private CharSequence mDrawerTitle;
    private CharSequence mTitle;

    private String[] navMenuItems;

    private List<String> listDataHeader=null;
    private HashMap<String,List<String>> listDataChild=null;
    private ExpandableListView mDrawerList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_home);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        mTitle=mDrawerTitle=getTitle();

        navMenuItems=getResources().getStringArray(R.array.nav_drawer_item);

        mDrawerLayout=(DrawerLayout)findViewById(R.id.drawer_layout);
        mDrawerList=(ExpandableListView)findViewById(R.id.list_slidermenu);

        //Setting adapter
        prepareListData();

        adapter=new ExpandableListAdapter(getApplicationContext(),listDataHeader,listDataChild);
        mDrawerList.setAdapter(adapter);

        mDrawerList.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
            @Override
            public boolean onGroupClick(ExpandableListView parent, View v,
                                        int groupPosition, long id) {
                return groupPosition == 0;
            }
        });

        mDrawerList.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {

            @Override
            public boolean onChildClick(ExpandableListView parent, View v,
                                        int groupPosition, int childPosition, long id) {
                Fragment fragment = null;

                switch (groupPosition) {
                    case 0:
                        fragment = new HomeFragment();
                        break;
                    case 1:
                        switch (childPosition) {
                            case 0:
                                fragment=new SareesFragment();
                                break;
                        }
                        break;
                }
                if (fragment != null) {
                    FragmentManager fragmentManager = getSupportFragmentManager();
                    fragmentManager.beginTransaction()
                            .replace(R.id.frame_container, fragment).commit();
                    mDrawerList.setItemChecked(childPosition, true);
                    mDrawerList.setSelection(childPosition);
                    setTitle(navMenuItems[childPosition]);
                    mDrawerLayout.closeDrawer(mDrawerList);
                } else {
                    Log.e("MainActivity", "Error in creating fragment");
                }
                return false;
            }
        });
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setHomeButtonEnabled(true);

        mDrawerToggle=new ActionBarDrawerToggle(this,mDrawerLayout,R.string.app_name,R.string.app_name){
            public void onDrawerClosed(View view) {
                getSupportActionBar().setTitle(mTitle);
                invalidateOptionsMenu();
            }

            public void onDrawerOpened(View drawerView) {
                getSupportActionBar().setTitle(mDrawerTitle);
                invalidateOptionsMenu();
            }
        };
        mDrawerLayout.setDrawerListener(mDrawerToggle);

        if (savedInstanceState == null) {
            //displayView(0);
        }

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
    }
    private void prepareListData(){
        listDataHeader=new ArrayList<>();
        listDataChild=new HashMap<>();

        listDataHeader.add(navMenuItems[0]);
        listDataHeader.add(navMenuItems[1]);
        listDataHeader.add(navMenuItems[2]);
        listDataHeader.add(navMenuItems[3]);
        listDataHeader.add(navMenuItems[4]);
        listDataHeader.add(navMenuItems[5]);
        listDataHeader.add(navMenuItems[6]);

        List<String> home=new ArrayList<>();

                                            //Sub-Menu For SAREES
        List<String> sarees=new ArrayList<>();
        sarees.add("a");
        sarees.add("b");
        sarees.add("c");
        sarees.add("d");

        listDataChild.put(listDataHeader.get(1),sarees);
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_home, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        if (mDrawerToggle.onOptionsItemSelected(item)) {
            return true;
        }

        int id = item.getItemId();
        switch (id){
            case R.id.action_settings:
                return true;

            case R.id.action_search:
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {
        boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
        menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
        return super.onPrepareOptionsMenu(menu);
    }

    private void displayView(int position) {
        Fragment fragment = null;
        switch (position) {
            case 0:
                fragment=new HomeFragment();
                break;
            case 1:
                fragment=new SareesFragment();
                break;
            case 2:

                break;
            case 3:

                break;
            case 4:

                break;
            case 5:

                break;
            default:
                break;
        }

        if (fragment != null) {
            FragmentManager fragmentManager=getSupportFragmentManager();
            fragmentManager.beginTransaction()
                    .replace(R.id.frame_container, fragment).commit();

            mDrawerList.setItemChecked(position, true);
            mDrawerList.setSelection(position);
            setTitle(navMenuItems[position]);
            mDrawerLayout.closeDrawer(mDrawerList);
        } else {
            Log.e("MainActivity", "Error in creating fragment");
        }
    }
    @Override
    public void setTitle(CharSequence title) {
        mTitle = title;
        try {
            getSupportActionBar().setTitle(mTitle);
        }
        catch (NullPointerException e){
            e.printStackTrace();
        }
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        mDrawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        mDrawerToggle.onConfigurationChanged(newConfig);
    }
}

请帮我解决这个问题。

Answer 1

首先，删除expandable listview的默认图标

<ExpandableListView [...] 
    android:groupIndicator="@null" />

并且在getGroupView方法的Expandable listview适配器中使用以下代码

@Override
public View getGroupView(int groupPosition, boolean isExpanded,
                         View convertView, ViewGroup parent) {
    String headerTitle = (String) getGroup(groupPosition);
    if (convertView == null) {
        LayoutInflater infalInflater = (LayoutInflater) this._context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = infalInflater.inflate(R.layout.YOUR_LIST_GROUP_XML, null);
    }

    TextView header_tv = (TextView) convertView.findViewById(R.id.list_header_tv);
    ImageView arrow_iv =(ImageView) convertView.findViewById(R.id.arrow_iv);


    header_tv.setText(headerTitle);

    Boolean check = false;

    try {


        YOUR_HAS_MAP_LIST.get(this._listDataHeader.get(groupPosition))
                .get(0);
    }
    catch (Exception ex)
    {
        check = true;
        ex.printStackTrace();
    }
    if(check)
    {
        arrow_iv.setVisibility(View.INVISIBLE);
    }

    if(isExpanded)
    {
        arrow_iv.setImageResource(R.drawable.UP_ARROW);
    }
    else
    {
        arrow_iv.setImageResource(R.drawable.DOWN_ARROW);
    }

    return convertView;
}

Answer 2

上述答案中存在单一问题。当您展开类别时，其他类别的图标也会被禁用。因为，在第一次代码尝试时，它不会超出try，直到你的listdatachild.get（listdataheader.get（i））。get（0）找到。所以，它不会每次都在（检查）。因此，图标被隐藏了。

以下是完美的解决方案

@Override
public View getGroupView(int groupPosition, boolean isExpanded,
                         View convertView, ViewGroup parent) {
    String headerTitle = (String) getGroup(groupPosition);
    if (convertView == null) {
        LayoutInflater infalInflater = (LayoutInflater) this._context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = infalInflater.inflate(R.layout.YOUR_LIST_GROUP_XML, null);
    }

    TextView header_tv = (TextView) convertView.findViewById(R.id.list_header_tv);
    ImageView arrow_iv =(ImageView) convertView.findViewById(R.id.arrow_iv);


    header_tv.setText(headerTitle);

    Boolean check = false;

    try {


        if(YOUR_HAS_MAP_LIST.get(this._listDataHeader.get(groupPosition))
                .get(0)==null){}
        else{
             if (isExpanded) {
                arrow_iv.setImageResource(R.drawable.arrow_up);
            } else {
                arrow_iv.setImageResource(R.drawable.arrow_down);
            }
         }
    }
    catch (Exception ex)
    {
        check = true;
        ex.printStackTrace();
    }
    if(check)
    {
        arrow_iv.setVisibility(View.INVISIBLE);
    }
    else{
        arrow_iv.setVisibility(View.VISIBLE);
    }
    return convertView;
}

如何从android中的标题中禁用Expandable Listview图标？

2 个答案: