Android仿QQ好友列表分组实现增删改及持久化

2020-04-11 10:56:31

字体：大中小

来源：转载

供稿：网友

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；

以上就是本文的全部内容，希望对大家的学习有所帮助。

上一篇：Android线程管理之ActivityThread

下一篇：Android EditText限制输入字数的方法