Android开发

Android仿QQ好友列表分组实现增删改及持久化

本文主要是介绍Android仿QQ好友列表分组实现增删改及持久化,对大家解决编程问题具有一定的参考价值,需要的程序猿们随着小编来一起学习吧!

Android自带的控件ExpandableListView实现了分组列表功能,本案例在此基础上进行优化,为此控件添加增删改分组及子项的功能,以及列表数据的持久化。

Demo实现效果:

 

GroupListDemo具体实现:

①demo中将列表页面设计为Fragment页面,方便后期调用;在主界面MainActivity中动态添加GroupListFragment页面;

MainActivity.java

package com.eric.grouplistdemo; 
 
 
import android.app.Activity; 
import android.app.Fragment; 
import android.app.FragmentManager; 
import android.os.Bundle; 
import android.widget.RelativeLayout; 
 
public class MainActivity extends Activity { 
 public static GroupListFragment fragment; 
  
 @Override 
 protected void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.activity_main); 
   
  fragment = new GroupListFragment(); 
   
  getFragmentManager().beginTransaction() 
  .replace(R.id.fragContainer, fragment).commit(); 
   
 } 
} 

动态添加GroupListFragment实例到界面的fragContainer布局中;将fragment声明为static用于在Adapter中组添加子项时进行调用。

activity_main.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="match_parent" 
 android:orientation="vertical" > 
 <RelativeLayout 
  android:id="@+id/fragContainer" 
  android:layout_width="match_parent" 
  android:layout_height="match_parent" 
  > 
 </RelativeLayout> 
</LinearLayout> 

②实现自定义适配器类MyAdapter,继承自BaseExpandableListAdapter;组项布局及子项布局;

list_item_parent.xml组项布局文件,展开图标及名称,增删图标;

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="match_parent" 
 android:layout_height="50dp" 
 android:background="#0099ff" 
 android:orientation="horizontal"> 
 <ImageView 
  android:id="@+id/image_parent" 
  android:layout_width="50dp" 
  android:layout_height="50dp" 
  android:src="@drawable/image_parent1"/> 
 <TextView 
  android:id="@+id/text_parent" 
  android:layout_width="wrap_content" 
  android:layout_height="50dp" 
  android:textColor="#FFF" 
  android:textSize="20sp" 
  android:text="parent1" 
  android:layout_toRightOf="@id/image_parent" 
  android:gravity="center"/> 
 <ImageView 
  android:id="@+id/image_delete" 
  android:layout_width="40dp" 
  android:layout_height="40dp" 
  android:layout_centerVertical="true" 
  android:layout_alignParentRight="true" 
  android:src="@drawable/delete"/> 
 <ImageView 
  android:id="@+id/image_add" 
  android:layout_width="40dp" 
  android:layout_height="40dp" 
  android:layout_centerVertical="true" 
  android:layout_toLeftOf="@id/image_delete" 
  android:src="@drawable/add"/> 
</RelativeLayout>

list_item_child.xml子项布局文件,名称及删除图标;

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="match_parent" 
 android:layout_height="40dp" 
 > 
 <TextView 
  android:id="@+id/text_child" 
  android:layout_width="wrap_content" 
  android:layout_height="40dp" 
  android:layout_margin="5dp" 
  android:textColor="#0099ff" 
  android:text="child" 
  android:layout_centerInParent="true" 
  android:gravity="center"/> 
 <ImageView 
  android:id="@+id/image_delete" 
  android:layout_width="40dp" 
  android:layout_height="40dp" 
  android:layout_alignParentRight="true" 
  android:layout_centerVertical="true" 
  android:src="@drawable/delete"/> 
</RelativeLayout> 

MyAdapter.java自定义适配器

package com.eric.grouplistdemo; 
 
import java.util.List; 
import java.util.Map; 
 
import android.content.Context; 
import android.util.Log; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.view.ViewGroup; 
import android.widget.BaseExpandableListAdapter; 
import android.widget.EditText; 
import android.widget.ImageView; 
import android.widget.TextView; 
 
public class MyAdapter extends BaseExpandableListAdapter{ 
 private List<String> parentList; 
 private Map<String,List<String>> map; 
 private Context context; 
 private EditText edit_modify; 
 private ModifyDialog dialog; 
  
 //构造函数 
 public MyAdapter(Context context, List<String> parentList, Map<String,List<String>> map) { 
  this.context = context; 
  this.parentList = parentList; 
  this.map = map; 
 } 
  
 //获取分组数 
 @Override 
 public int getGroupCount() { 
  return parentList.size(); 
 } 
 //获取当前组的子项数 
 @Override 
 public int getChildrenCount(int groupPosition) { 
  String groupName = parentList.get(groupPosition); 
  int childCount = map.get(groupName).size(); 
  return childCount; 
 } 
 //获取当前组对象 
 @Override 
 public Object getGroup(int groupPosition) { 
  String groupName = parentList.get(groupPosition); 
  return groupName; 
 } 
 //获取当前子项对象 
 @Override 
 public Object getChild(int groupPosition, int childPosition) { 
  String groupName = parentList.get(groupPosition); 
  String chidlName = map.get(groupName).get(childPosition); 
  return chidlName; 
 } 
 //获取组ID 
 @Override 
 public long getGroupId(int groupPosition) { 
  return groupPosition; 
 } 
 //获取子项ID 
 @Override 
 public long getChildId(int groupPosition, int childPosition) { 
  return childPosition; 
 } 
 
 @Override 
 public boolean hasStableIds() { 
  return true; 
 } 
 //组视图初始化 
 @Override 
 public View getGroupView(int groupPosition, boolean isExpanded, 
   View convertView, ViewGroup parent) { 
  final int groupPos = groupPosition; 
   
  if(convertView == null){ 
   convertView = LayoutInflater.from(context).inflate(R.layout.list_item_parent, null); 
  } 
   
  ImageView image = (ImageView) convertView.findViewById(R.id.image_parent); 
  ImageView image_add = (ImageView) convertView.findViewById(R.id.image_add); 
  ImageView image_delete = (ImageView) convertView.findViewById(R.id.image_delete); 
   
  if(isExpanded){ 
   image.setImageResource(R.drawable.image_parent2); 
  }else{ 
   image.setImageResource(R.drawable.image_parent1); 
  } 
   
  image_add.setOnClickListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    alertAddDialog(MainActivity.fragment.getActivity(), "新增子项", groupPos); 
   } 
  }); 
  image_delete.setOnClickListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    GroupListFragment.deleteGroup(groupPos); 
   } 
  }); 
   
   
  TextView parentText = (TextView) convertView.findViewById(R.id.text_parent); 
  parentText.setText(parentList.get(groupPosition)); 
  return convertView; 
 } 
 //子项视图初始化 
 @Override 
 public View getChildView(int groupPosition, int childPosition, 
   boolean isLastChild, View convertView, ViewGroup parent) { 
  final int groupPos = groupPosition; 
  final int childPos = childPosition; 
   
  if(convertView == null){ 
   convertView = LayoutInflater.from(context).inflate(R.layout.list_item_child, null); 
  } 
  TextView childText = (TextView) convertView.findViewById(R.id.text_child); 
  ImageView image_delete = (ImageView) convertView.findViewById(R.id.image_delete); 
  String parentName = parentList.get(groupPosition); 
  String childName = map.get(parentName).get(childPosition); 
  childText.setText(childName); 
   
  image_delete.setOnClickListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    GroupListFragment.deleteChild(groupPos, childPos); 
   } 
  }); 
  return convertView; 
 } 
 
 @Override 
 public boolean isChildSelectable(int groupPosition, int childPosition) { 
  return true; 
 } 
  
 //弹新增子项对话框 
 public void alertAddDialog(Context context, String title, int currentGroup){ 
  final int group = currentGroup; 
   
  dialog = new ModifyDialog(context, title, null); 
  edit_modify = dialog.getEditText(); 
  dialog.setOnClickCommitListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    GroupListFragment.addChild(group, edit_modify.getText().toString()); 
    dialog.dismiss(); 
   } 
  }); 
  dialog.show(); 
 } 
} 

构造函数:将传入的parentList和map进行数据同步,parentList保存组数据,map保存对应组及其子项list数据;
获取分组数及子项数等很简单,就不介绍了,主要讲述一下,组视图初始化和子项视图初始化这两个函数;

组视图初始化getGroupView():尽量复用convertView防止内存泄露,首先是进行判断,若convertView为空,则进行组视图初始化,加载list_item_parent子项布局;获取到相应的组布局控件:展开图标image、添加图标image_add、删除图标image_delete;通过传递过来的布尔类型参数isExpanded,进行判断给image赋值展开图标或合并图标;分别给添加图标和删除图标添加点击事件,分别调用GroupListFragment中的弹出添加窗口函数alertAddDialog()和删除组函数deleteGroup();

子项视图初始化getChildView():同样尽量复用convertView防止内存泄露,首先是进行判断,若convertView为空,则进行子项视图初始化,加载list_item_child子项布局;获取到相应的子布局控件:内容文本ChildText和删除图标Image_delete;从parentList和map中分别获取到,当前子项的组名parentName和子项名childName,赋值ChildText,删除图标添加点击事件,调用删除子项函数deleteChild();

③实现自定义对话框类ModifyDialog,继承自Dialog类,对输入修改内容,或新增项内容进行过渡;

no_title_dialog.xml,在values目录下自定义Dialog的style类型xml,除去Dialog的标题栏;

<?xml version="1.0" encoding="utf-8"?> 
<resources xmlns:android="http://schemas.android.com/apk/res/android"> 
 <style name="noTitleDialog" parent="android:style/Theme.Dialog"> 
  <item name="android:width">300dp</item> 
  <item name="android:height">40dp</item> 
  <item name="android:windowNoTitle">true</item> 
 </style> 
</resources> 

dialog_modify.xml 自定义对话框的布局文件,标题文本,输入框,确定按钮;

<?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="match_parent" 
 android:orientation="vertical" > 
 <TextView 
  android:id="@+id/text_title" 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:layout_gravity="center_horizontal" 
  android:gravity="center" 
  android:background="#0099ff" 
  android:text="修改名称" 
  android:textColor="#FFF" 
  android:textSize="20sp"/> 
 <EditText 
  android:id="@+id/edit_modify" 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="组名称"/> 
 <Button 
  android:id="@+id/btn_commit" 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="确定" 
  android:textColor="#FFF" 
  android:background="#0099ff" 
  /> 
</LinearLayout> 

ModifyDialog.java

package com.eric.grouplistdemo; 
 
import android.app.Dialog; 
import android.content.Context; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 
public class ModifyDialog extends Dialog{ 
 private TextView text_title; 
 private EditText edit_modify; 
 private Button btn_commit; 
  
 public ModifyDialog(Context context, String title, String name) { 
  super(context, R.style.noTitleDialog); 
   
  View view = LayoutInflater.from(getContext()) 
    .inflate(R.layout.dialog_modify, null); 
  text_title = (TextView) view.findViewById(R.id.text_title); 
  edit_modify = (EditText)view.findViewById(R.id.edit_modify); 
  btn_commit = (Button) view.findViewById(R.id.btn_commit); 
  text_title.setText(title); 
  edit_modify.setText(name); 
   
  super.setContentView(view); 
 } 
  
 public EditText getEditText(){ 
  return edit_modify; 
 } 
  
 public void setOnClickCommitListener(View.OnClickListener listener){ 
  btn_commit.setOnClickListener(listener); 
 } 
} 

ModifyDialog自定义构造函数中,通过super()加载刚刚自定义的no_title_dialog.xml,声明View加载layout布局dialog_modify.xml;并且获取布局中的相应控件,将构造函数中传来的字符串title和name,分别赋值到标题文本和输入框控件中;最后调用setContentView()初始化对话框视图;
添加一个返回输入框控件的函数getEditText(),用于获取输入框输入的内容;

还需要一个自定义的点击事件监听器,绑定在确定按钮上; 

④准备工作都完成了,下面就实现GroupListFragment,包括数据的初始化及持久化保存,组项和子项的增删改操作,列表子项点击事件,列表组项和子项的长按事件; 

fragment_group_list.xml 页面的布局文件ExpandableListView列表以及一个添加组图标;

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="match_parent" 
 android:layout_height="match_parent" 
 > 
 <ExpandableListView 
  android:id="@+id/expandablelistview" 
  android:layout_width="match_parent" 
  android:layout_height="match_parent" 
  android:groupIndicator="@null" 
  > 
 </ExpandableListView> 
 <ImageView 
  android:id="@+id/image_add" 
  android:layout_width="40dp" 
  android:layout_height="40dp" 
  android:layout_centerHorizontal="true" 
  android:layout_alignParentBottom="true" 
  android:src="@drawable/add"/> 
</RelativeLayout> 

这里需要将ExpandableListView的groupIndicator属性设置为@null,不使用其自带的展开图标;

GroupListFragment.java 加载列表的页面

package com.eric.grouplistdemo; 
 
import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.List; 
import java.util.Map; 
 
import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 
 
import android.R.integer; 
import android.app.Fragment; 
import android.content.Context; 
import android.content.SharedPreferences; 
import android.content.SharedPreferences.Editor; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.view.ViewGroup; 
import android.widget.AdapterView; 
import android.widget.EditText; 
import android.widget.ExpandableListView; 
import android.widget.ImageView; 
import android.widget.Toast; 

public class GroupListFragment extends Fragment{ 
 private View view; 
 private ExpandableListView expandableListView; 
 public static MyAdapter adapter; 
 public static List<String> parentList; 
 public static Map<String,List<String>> map; 
 private ModifyDialog dialog; 
 private EditText edit_modify; 
 private ImageView image_add; 
 private int currentGroup,currentChild; 
 public static SharedPreferences sp; 
 public static Editor editor; 
 public static String dataMap,dataParentList; 
  
 @Override 
 public View onCreateView(LayoutInflater inflater, ViewGroup container, 
   Bundle savedInstanceState) { 
   
  view = inflater.inflate(R.layout.fragment_group_list, container, false); 
  expandableListView = (ExpandableListView) view.findViewById(R.id.expandablelistview); 
  image_add = (ImageView) view.findViewById(R.id.image_add); 
  image_add.setOnClickListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    alertAddDialog(getActivity(), "新增组"); 
   } 
  }); 
   
  initData(); 
   
  adapter = new MyAdapter(getActivity().getApplicationContext(), parentList, map); 
  expandableListView.setAdapter(adapter); 
   
  //设置子项点击事件 
  MyOnClickListener myListener = new MyOnClickListener(); 
  expandableListView.setOnChildClickListener(myListener); 
   
  //设置长按点击事件 
  MyOnLongClickListener myLongListener = new MyOnLongClickListener(); 
  expandableListView.setOnItemLongClickListener(myLongListener); 
   
  return view; 
 } 
  
 public void initData(){ 
  map = new HashMap<String, List<String>>(); 
  parentList = new ArrayList<String>(); 
   
  sp = getActivity().getApplicationContext().getSharedPreferences("spfile", getActivity().MODE_PRIVATE); 
  dataMap = sp.getString("dataMap", null); 
  dataParentList = sp.getString("dataParentList", null); 
   
  if(dataMap == null || dataParentList == null){ 
   parentList = new ArrayList<String>(); 
   parentList.add("客厅"); 
   parentList.add("厨房"); 
   parentList.add("卧室"); 
   
   List<String> list1 = new ArrayList<String>(); 
   list1.add("客厅空调"); 
   list1.add("客厅电视"); 
   list1.add("客厅电灯"); 
   map.put("客厅", list1); 
  
   List<String> list2 = new ArrayList<String>(); 
   list2.add("厨房油烟机"); 
   list2.add("厨房电灯"); 
   list2.add("厨房电器"); 
   map.put("厨房", list2); 
  
   List<String> list3 = new ArrayList<String>(); 
   list3.add("卧室空调"); 
   list3.add("卧室灯光"); 
   list3.add("卧室电视"); 
   map.put("卧室", list3); 
  }else{ 
   try { 
    //初始化parentList 
    JSONArray jsonArray = new JSONArray(dataParentList); 
    for (int i = 0; i < jsonArray.length(); i++) { 
     parentList.add(jsonArray.get(i).toString()); 
    } 
     
    //初始化map 
    JSONObject jsonObject = new JSONObject(dataMap); 
    for (int i = 0; i < jsonObject.length(); i++) { 
     String key = jsonObject.getString(parentList.get(i)); 
     JSONArray array = new JSONArray(key); 
     List<String> list = new ArrayList<String>(); 
     for (int j = 0; j < array.length(); j++) { 
      list.add(array.get(j).toString()); 
     } 
     map.put(parentList.get(i), list); 
    } 
     
    Log.d("eric", "①:"+map+"②:"+parentList); 
   } catch (JSONException e) { 
    e.printStackTrace(); 
    Log.e("eric","String转Map或List出错"+e); 
   } 
  } 
  Log.e("eric", dataMap+"!&&!"+dataParentList); 
  saveData(); 
 } 
  
 //自定义点击监听事件 
 public class MyOnClickListener implements ExpandableListView.OnChildClickListener{ 
  @Override 
  public boolean onChildClick(ExpandableListView parent, View v, 
    int groupPosition, int childPosition, long id) { 
   String str = "choose"+groupPosition+"-"+childPosition; 
   Toast.makeText(getActivity(), str, Toast.LENGTH_SHORT).show(); 
   return false; 
  } 
 } 
  
 //自定义长按监听事件 
 public class MyOnLongClickListener implements AdapterView.OnItemLongClickListener{ 
  @Override 
  public boolean onItemLongClick(AdapterView<?> parent, View view, 
    int position, long id) { 
   //长按子项 
   if (ExpandableListView.getPackedPositionType(id) == ExpandableListView.PACKED_POSITION_TYPE_CHILD){ 
    long packedPos = ((ExpandableListView) parent).getExpandableListPosition(position); 
    int groupPosition = ExpandableListView.getPackedPositionGroup(packedPos); 
    int childPosition = ExpandableListView.getPackedPositionChild(packedPos); 
     
    currentGroup = groupPosition; 
    currentChild = childPosition; 
     
    String str = (String)adapter.getChild(groupPosition, childPosition); 
    alertModifyDialog("修改此项名称",str); 
    Toast.makeText(getActivity(),str,Toast.LENGTH_SHORT).show(); 
    return true; 
   //长按组 
   }else if(ExpandableListView.getPackedPositionType(id) == ExpandableListView.PACKED_POSITION_TYPE_GROUP){ 
    long packedPos = ((ExpandableListView) parent).getExpandableListPosition(position); 
    int groupPosition = ExpandableListView.getPackedPositionGroup(packedPos); 
    int childPosition = ExpandableListView.getPackedPositionChild(packedPos); 
     
    currentGroup = groupPosition; 
    currentChild = childPosition; 
     
    String group = parentList.get(groupPosition); 
    alertModifyDialog("修改组名称", group); 
     
    String str = (String)adapter.getGroup(groupPosition); 
    Toast.makeText(getActivity(),str,Toast.LENGTH_SHORT).show(); 
   } 
    return false; 
   } 
 } 
  
 //新增组 
 public static void addGroup(String newGroupName){ 
  parentList.add(newGroupName); 
  List<String> list = new ArrayList<String>(); 
  map.put(newGroupName, list); 
  adapter.notifyDataSetChanged(); 
  saveData(); 
 } 
  
 //新增子项到指定组 
 public static void addChild(int groupPosition, String newChildName){ 
  String groupName = parentList.get(groupPosition); 
  List<String> list = map.get(groupName); 
  list.add(newChildName); 
  adapter.notifyDataSetChanged(); 
  saveData(); 
 } 
  
 //删除指定组 
 public static void deleteGroup(int groupPos){ 
  String groupName = parentList.get(groupPos); 
  map.remove(groupName); 
  parentList.remove(groupPos); 
  adapter.notifyDataSetChanged(); 
  saveData(); 
 } 
 //删除指定子项 
 public static void deleteChild(int groupPos, int childPos){ 
  String groupName = parentList.get(groupPos); 
  List<String> list = map.get(groupName); 
  list.remove(childPos); 
  adapter.notifyDataSetChanged(); 
  saveData(); 
 } 
  
 //修改该项名称 
 public void modifyName(int groupPosition, int childPosition, String modifyName){ 
  Toast.makeText(getActivity(), String.valueOf(groupPosition)+'-'+String.valueOf(childPosition), Toast.LENGTH_SHORT).show(); 
  if(childPosition<0){ 
   //修改组名称 
   String groupName = parentList.get(groupPosition); 
   if(!groupName.equals(modifyName)){ 
    map.put(modifyName, map.get(groupName)); 
    map.remove(groupName); 
    parentList.set(groupPosition, modifyName); 
   } 
    
  }else{ 
   //修改子项名称 
   String group = parentList.get(groupPosition); 
   List<String> list =map.get(group); 
   list.set(childPosition, modifyName); 
   map.put(group, list); 
  } 
  adapter.notifyDataSetChanged(); 
  saveData(); 
 } 
  
 //弹修改对话框 
 public void alertModifyDialog(String title, String name){ 
  dialog = new ModifyDialog(getActivity(), title, name); 
  edit_modify = dialog.getEditText(); 
  dialog.setOnClickCommitListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    modifyName(currentGroup, currentChild, edit_modify.getText().toString()); 
    dialog.dismiss(); 
   } 
  }); 
  dialog.show(); 
 } 
  
 //弹新增组对话框 
 public void alertAddDialog(Context context, String title){ 
  dialog = new ModifyDialog(context, title, null); 
  edit_modify = dialog.getEditText(); 
  dialog.setOnClickCommitListener(new OnClickListener() { 
   @Override 
   public void onClick(View v) { 
    addGroup(edit_modify.getText().toString()); 
    dialog.dismiss(); 
   } 
  }); 
  dialog.show(); 
 } 
  
 //保存数据 
 public static void saveData(){ 
  JSONObject jsonObject = new JSONObject(map); 
  dataMap = jsonObject.toString(); 
  dataParentList = parentList.toString(); 
   
  editor = sp.edit(); 
  editor.putString("dataMap", dataMap); 
  editor.putString("dataParentList", dataParentList); 
  editor.commit(); 
 } 
  
} 

内容有点多,一个个来:

初始化Fragment页面函数onCreateView():

首先,要进行layout布局fragment_group_list.xml加载,获取相应控件的实例,expandableListView列表控件以及添加组图标image_add,添加组图标添加点击事件;调用initData()方法进行组数据parentList和组对应子项map的初始化;然后,实例化adapter传入parentList和map数据到自定义适配器MyAdapter中,并将其绑定到expandableListView上;最后,给expandableListView添加自定义子项点击事件监听器,组项和子项长按事件监听器;

初始化数据函数initData():该函数通过ShareReference来保存数据;

首先,实例化parentList和map,从ShareReference中获取到保存的String类型的parentList和map实际数据,赋值到dataMap和dataParentList中,若当中数据不存在,默认返回null,第一次运行程序的时候肯定是没有数据的,故进行判断,若没获取到数据,那就给parentList和Map赋值“客厅”、“厨房”、“卧室”等一系列数据;如果有数据的话,那就得进行数据的转换,因为之前保存的String类型数据,parentList初始化:将dataParentList转换为JSONArray类型,通过循环将数据赋值到parentList中;同理,将dataMap转换为JSONObject类型,通过两层for循环将数据赋值到map中。

自定义点击子项监听其类MyOnClickListener:实现ExpandableListView.OnChildClickListener接口,这里就简单的进行Toast操作,读者可以修改为跳转等其他自定义功能;

自定义长按组项或子项监听器类MyOnLongClickListener:实现AdapterView.OnItemLongClickListener接口,通过调用ExpandableListView的getPackedPositionType()方法来判断此时长按的是组项还是子项;这里将长按组和子项分离出来,方便根据功能修改;无论是组项还是子项长按后,都调用alertModifyDialog()弹修改对话框,传入当前项的名称;
新增组addGroup函数:将传递过来的newGroupName,添加parentList中,且定义一个空的list,绑定newGroupName,将这对string和list,添加到map中;最后,调用adapter.notifyDataSetChanged()刷新列表,调用saveData()保存数据到ShareReference;

同理,新增子项到指定组addChild(),删除指定组deleteGroup(),删除指定子项deleteChild(),都是对parentList和map进行操作,最后刷新列表和保存数据;

修改该项名称modifyName():通过传递过来childPosition进行判断,当修改项为组项时,childPosition的值为-1,以此区分组项和子项;这里遇到一个问题,当组项提交的名称与原名称相同会报错,故添加一个判断,仅提交的名称不同时才进行修改操作;修改的具体实现还是对parentList和map的操作,以修改组项为例,同新增组,添加一个modifyName的组,其对应的List为原来组名对应的List数据,然后再将原来的groupName组及其对应的list删除,实现修改;最后同样要刷新列表和保存数据;

弹修改对话框alertModifyDialog()函数:首先对自定义的dialog进行实例化,初始化标题和输入框中的数据;调用getEditText()函数获取输入框实例,添加提交按钮点击事件,调用modifyName方法传入当前组和子项数据,以及输入框中提交的文本;
弹新增组对话框alertAddDialog()函数:同样,实例化dialog,获取输入框控件,点击事件中调用addGroup()方法添加数据;

保存数据saveData()函数:将parentList和map数据转化为String类型,分别赋值,保存至ShareReference的Editor中并提交;

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