Question

我在android中遇到了expandableListView的问题（我使用android studio）。我在网上找到了一个关于expandableListVIew的教程，一切正常，但现在我想在每个ListGroup中添加一个可点击的图像。

我在每个组中添加了一个小修改图标，但现在我真的不知道当用户点击它时如何在主程序中执行某些操作。

MainActivity.java

package com.luca.mattia.password;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;


import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
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.ImageView;
import android.widget.RelativeLayout;
import android.widget.Toast;

public class MainActivity extends Activity {

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

Boolean aperto[] = new Boolean[500];
int img_cont = 0;

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

    for(int i = 0; i < 500; i ++)
    {
        aperto[i] = false;
    }
    // get the listview
    expListView = (ExpandableListView) findViewById(R.id.lvExp);

    // preparing list data
    prepareListData();

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

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

    //listener for child row click
    expListView.setOnChildClickListener(myListItemClicked);
    expListView.setOnGroupClickListener(myListGroupClicked);
}

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

    // Adding child data
    listDataHeader.add("uno");
    listDataHeader.add("due");
    listDataHeader.add("tre");

    // Adding child data
    List<String> top250 = new ArrayList<String>();
    top250.add("E-mail: e-mail");
    top250.add("Username: un");
    top250.add("Password: QWERTY");
    top250.add("Chiave: __________");
    add_img();

    List<String> nowShowing = new ArrayList<String>();
    nowShowing.add("The Conjuring");
    nowShowing.add("Despicable Me 2");
    nowShowing.add("Turbo");
    nowShowing.add("Grown Ups 2");
    nowShowing.add("Red 2");
    nowShowing.add("The Wolverine");
    add_img();

    List<String> comingSoon = new ArrayList<String>();
    comingSoon.add("2 Guns");
    comingSoon.add("The Smurfs 2");
    comingSoon.add("The Spectacular Now");
    comingSoon.add("The Canyons");
    comingSoon.add("Europa Report");
    add_img();

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

//our child listener
private OnChildClickListener myListItemClicked =  new OnChildClickListener() {

    public boolean onChildClick(ExpandableListView parent, View v,
                                int groupPosition, int childPosition, long id) {

        Toast.makeText(getBaseContext(), "Child clicked",
               Toast.LENGTH_LONG).show();
        return false;
    }

};

private OnGroupClickListener myListGroupClicked =  new OnGroupClickListener() {

    public boolean onGroupClick(ExpandableListView parent, View v,
                                int groupPosition, long id) {


        ImageView img = (ImageView)  findViewById(R.id.icona_modifica);

        if(aperto[(int)id] == false)
        {
            img.setVisibility(View.VISIBLE);
            aperto[(int)id] = true;
        }
        else
        {
            img.setVisibility(View.INVISIBLE);
            aperto[(int)id] = false;
        }

        return false;
    }

  };
}

ExpandableListAdapter.java

package com.luca.mattia.password;

/**
  * Created by Mattia on 29/11/2014.
*/
import java.util.HashMap;
import java.util.List;

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

public class ExpandableListAdapter extends BaseExpandableListAdapter {

private Context _context;
private List<String> _listDataHeader; // header titles
// child data in format of header title, child title
private HashMap<String, List<String>> _listDataChild;

public ExpandableListAdapter(Context context, List<String> listDataHeader,
                             HashMap<String, List<String>> listChildData) {
    this._context = context;
    this._listDataHeader = listDataHeader;
    this._listDataChild = listChildData;
}

@Override
public Object getChild(int groupPosition, int childPosititon) {
    return this._listDataChild.get(this._listDataHeader.get(groupPosition))
            .get(childPosititon);
}

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

@Override
public View getChildView(int groupPosition, final int childPosition,
                         boolean isLastChild, View convertView, ViewGroup parent) {

    final String childText = (String) getChild(groupPosition, childPosition);

    if (convertView == null) {
        LayoutInflater infalInflater = (LayoutInflater) this._context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = infalInflater.inflate(R.layout.list_item, null);
    }

    TextView txtListChild = (TextView) convertView
            .findViewById(R.id.lblListItem);

    txtListChild.setText(childText);
    return convertView;
}

@Override
public int getChildrenCount(int groupPosition) {
    return this._listDataChild.get(this._listDataHeader.get(groupPosition))
            .size();
}

@Override
public Object getGroup(int groupPosition) {
    return this._listDataHeader.get(groupPosition);
}

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

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

@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.list_group, null);
    }

    ImageView lblListHeader = (ImageView) convertView
            .findViewById(R.id.lblListHeader);

    return convertView;
}

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

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

list_item.xml

<?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/lblListItem"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:textSize="17dip"
       android:paddingTop="5dp"
       android:paddingBottom="5dp"
       android:singleLine="true"
       android:paddingLeft="?android:attr/expandableListPreferredChildPaddingLeft" />

  </LinearLayout>

list_group.xml

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

      <!-- <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="#009933" /> -->

      <ImageView
         android:id="@+id/lblListHeader"
         android:layout_width="match_parent"
         android:layout_height="95dp"
         android:background="@drawable/striscia_ignoto"/>

      <ImageView
         android:id="@+id/icona_modifica"
         android:layout_width="22dp"
         android:layout_height="22dp"
         android:layout_alignParentRight="true"
         android:layout_alignParentBottom="true"
         android:visibility="visible"
         android:background="@drawable/icona_modifica"/>

  </RelativeLayout>

感谢所有人。

P.S。对不起我的英文

Answer 1

您可以在getGroupView（）方法中添加图像clickListener：

@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.list_group, null);
    }

    ImageView lblListHeader = (ImageView) convertView.findViewById(R.id.lblListHeader);

    ImageView iconaModifica= (ImageView) convertView.findViewById(R.id.icona_modifica);
    iconaModifica.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
               // do your stuff here
              Toast.makeText(_context, "Group position: "+groupPosition, Toast.LENGTH_LONG).show();
        }
    });

    return convertView;
}

<强>更新

如果您想在活动中获得clickListener，可以通过实现界面来实现。

为此，您需要：

1）创建接口类

public interface IExpandableListInterface {

    public void onClickIconaModifica(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent); // you can change the method parameters if you want

}

2）在您的活动中实施界面并添加方法：

    public class MainActivity extends Activity implements IExpandableListInterface{

        public void onClickIconaModifica(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent){
             // do your stuff here
              Toast.makeText(MainActivity.this, "Group position: "+groupPosition, Toast.LENGTH_LONG).show();


        }
   }

3）将接口传递给适配器：

   listAdapter = new ExpandableListAdapter(this, this, listDataHeader, listDataChild);
//PS: the first "this" is for the context and the second "this" is for the interface

4）更改适配器构造函数：

private Context _context;
private List<String> _listDataHeader; // header titles
// child data in format of header title, child title
private HashMap<String, List<String>> _listDataChild;
private IExpandableListInterface mMyInterface;

public ExpandableListAdapter(Context context, IExpandableListInterface myInterface, List<String> listDataHeader,
                             HashMap<String, List<String>> listChildData) {
    this._context = context;
    this._listDataHeader = listDataHeader;
    this._listDataChild = listChildData;
    this.mMyInterface = myInterface;
}

5）在适配器中使用你的接口（在你喜欢的情况下你想在getGroupView（）中调用它）：

@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.list_group, null);
        }

        ImageView lblListHeader = (ImageView) convertView.findViewById(R.id.lblListHeader);

        ImageView iconaModifica= (ImageView) convertView.findViewById(R.id.icona_modifica);
        iconaModifica.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                mMyInterface.onClickIconaModifica(groupPosition, isExpanded, convertView, parent)
            }
        });

        return convertView;
    }

6）好吧，没有第6步。只需运行你的应用程序，我希望能帮到你！

在expandableListView中添加可单击的imageView

1 个答案: