Android自帶的控件ExpandableListView實現了分組列表功能，本案例在此基礎上進行優化，為此控件添加增刪改分組及子項的功能，以及列表數據的持久化。
Demo實現效果：
GroupListDemo具體實現：
①demo中將列表頁面設計為Fragment頁面，方便后期調用；在主界面MainActivity中動態添加GroupListFragment頁面；
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(); } } 動態添加GroupListFragment實例到界面的fragContainer布局中；將fragment聲明為static用于在Adapter中組添加子項時進行調用。
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實現自定義適配器類MyAdapter，繼承自BaseExpandableListAdapter；組項布局及子項布局；
list_item_parent.xml組項布局文件，展開圖標及名稱，增刪圖標；
<?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子項布局文件，名稱及刪除圖標；
<?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自定義適配器
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; //構造函數 public MyAdapter(Context context, List<String> parentList, Map<String,List<String>> map) { this.context = context; this.parentList = parentList; this.map = map; } //獲取分組數 @Override public int getGroupCount() { return parentList.size(); } //獲取當前組的子項數 @Override public int getChildrenCount(int groupPosition) { String groupName = parentList.get(groupPosition); int childCount = map.get(groupName).size(); return childCount; } //獲取當前組對象 @Override public Object getGroup(int groupPosition) { String groupName = parentList.get(groupPosition); return groupName; } //獲取當前子項對象 @Override public Object getChild(int groupPosition, int childPosition) { String groupName = parentList.get(groupPosition); String chidlName = map.get(groupName).get(childPosition); return chidlName; } //獲取組ID @Override public long getGroupId(int groupPosition) { return groupPosition; } //獲取子項ID @Override public long getChildId(int groupPosition, int childPosition) { return childPosition; } @Override public boolean hasStableIds() { return true; } //組視圖初始化 @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(), "新增子項", 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; } //子項視圖初始化 @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; } //彈新增子項對話框 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(); } } 構造函數：將傳入的parentList和map進行數據同步，parentList保存組數據，map保存對應組及其子項list數據；
獲取分組數及子項數等很簡單，就不介紹了，主要講述一下，組視圖初始化和子項視圖初始化這兩個函數；
組視圖初始化getGroupView()：盡量復用convertView防止內存泄露，首先是進行判斷，若convertView為空，則進行組視圖初始化，加載list_item_parent子項布局；獲取到相應的組布局控件：展開圖標image、添加圖標image_add、刪除圖標image_delete；通過傳遞過來的布爾類型參數isExpanded，進行判斷給image賦值展開圖標或合并圖標；分別給添加圖標和刪除圖標添加點擊事件，分別調用GroupListFragment中的彈出添加窗口函數alertAddDialog()和刪除組函數deleteGroup()；
子項視圖初始化getChildView()：同樣盡量復用convertView防止內存泄露，首先是進行判斷，若convertView為空，則進行子項視圖初始化，加載list_item_child子項布局；獲取到相應的子布局控件：內容文本ChildText和刪除圖標Image_delete；從parentList和map中分別獲取到，當前子項的組名parentName和子項名childName，賦值ChildText，刪除圖標添加點擊事件，調用刪除子項函數deleteChild()；
③實現自定義對話框類ModifyDialog，繼承自Dialog類，對輸入修改內容，或新增項內容進行過渡；
no_title_dialog.xml，在values目錄下自定義Dialog的style類型xml，除去Dialog的標題欄；
<?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 自定義對話框的布局文件，標題文本，輸入框，確定按鈕；
<?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="修改名稱" android:textColor="#FFF" android:textSize="20sp"/> <EditText android:id="@+id/edit_modify" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="組名稱"/> <Button android:id="@+id/btn_commit" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="確定" 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自定義構造函數中，通過super()加載剛剛自定義的no_title_dialog.xml，聲明View加載layout布局dialog_modify.xml;并且獲取布局中的相應控件，將構造函數中傳來的字符串title和name，分別賦值到標題文本和輸入框控件中；最后調用setContentView()初始化對話框視圖；
添加一個返回輸入框控件的函數getEditText()，用于獲取輸入框輸入的內容；
還需要一個自定義的點擊事件監聽器，綁定在確定按鈕上；
④準備工作都完成了，下面就實現GroupListFragment，包括數據的初始化及持久化保存，組項和子項的增刪改操作，列表子項點擊事件，列表組項和子項的長按事件；
fragment_group_list.xml 頁面的布局文件ExpandableListView列表以及一個添加組圖標；
<?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>
這里需要將ExpandableListView的groupIndicator屬性設置為@null，不使用其自帶的展開圖標；
GroupListFragment.java 加載列表的頁面
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(), "新增組"); } }); initData(); adapter = new MyAdapter(getActivity().getApplicationContext(), parentList, map); expandableListView.setAdapter(adapter); //設置子項點擊事件 MyOnClickListener myListener = new MyOnClickListener(); expandableListView.setOnChildClickListener(myListener); //設置長按點擊事件 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("客廳"); parentList.add("廚房"); parentList.add("臥室"); List<String> list1 = new ArrayList<String>(); list1.add("客廳空調"); list1.add("客廳電視"); list1.add("客廳電燈"); map.put("客廳", list1); List<String> list2 = new ArrayList<String>(); list2.add("廚房油煙機"); list2.add("廚房電燈"); list2.add("廚房電器"); map.put("廚房", list2); List<String> list3 = new ArrayList<String>(); list3.add("臥室空調"); list3.add("臥室燈光"); list3.add("臥室電視"); map.put("臥室", 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轉Map或List出錯"+e); } } Log.e("eric", dataMap+"!&&!"+dataParentList); saveData(); } //自定義點擊監聽事件 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; } } //自定義長按監聽事件 public class MyOnLongClickListener implements AdapterView.OnItemLongClickListener{ @Override public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) { //長按子項 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("修改此項名稱",str); Toast.makeText(getActivity(),str,Toast.LENGTH_SHORT).show(); return true; //長按組 }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("修改組名稱", group); String str = (String)adapter.getGroup(groupPosition); Toast.makeText(getActivity(),str,Toast.LENGTH_SHORT).show(); } return false; } } //新增組 public static void addGroup(String newGroupName){ parentList.add(newGroupName); List<String> list = new ArrayList<String>(); map.put(newGroupName, list); adapter.notifyDataSetChanged(); saveData(); } //新增子項到指定組 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(); } //刪除指定組 public static void deleteGroup(int groupPos){ String groupName = parentList.get(groupPos); map.remove(groupName); parentList.remove(groupPos); adapter.notifyDataSetChanged(); saveData(); } //刪除指定子項 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(); } //修改該項名稱 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){ //修改組名稱 String groupName = parentList.get(groupPosition); if(!groupName.equals(modifyName)){ map.put(modifyName, map.get(groupName)); map.remove(groupName); parentList.set(groupPosition, modifyName); } }else{ //修改子項名稱 String group = parentList.get(groupPosition); List<String> list =map.get(group); list.set(childPosition, modifyName); map.put(group, list); } adapter.notifyDataSetChanged(); saveData(); } //彈修改對話框 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(); } //彈新增組對話框 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(); } //保存數據 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(); } } 內容有點多，一個個來：
初始化Fragment頁面函數onCreateView():
首先，要進行layout布局fragment_group_list.xml加載，獲取相應控件的實例，expandableListView列表控件以及添加組圖標image_add，添加組圖標添加點擊事件；調用initData()方法進行組數據parentList和組對應子項map的初始化；然后，實例化adapter傳入parentList和map數據到自定義適配器MyAdapter中，并將其綁定到expandableListView上；最后，給expandableListView添加自定義子項點擊事件監聽器，組項和子項長按事件監聽器；
初始化數據函數initData():該函數通過ShareReference來保存數據；
首先，實例化parentList和map，從ShareReference中獲取到保存的String類型的parentList和map實際數據，賦值到dataMap和dataParentList中，若當中數據不存在，默認返回null，第一次運行程序的時候肯定是沒有數據的，故進行判斷，若沒獲取到數據，那就給parentList和Map賦值“客廳”、“廚房”、“臥室”等一系列數據；如果有數據的話，那就得進行數據的轉換，因為之前保存的String類型數據，parentList初始化：將dataParentList轉換為JSONArray類型，通過循環將數據賦值到parentList中；同理，將dataMap轉換為JSONObject類型，通過兩層for循環將數據賦值到map中。
自定義點擊子項監聽其類MyOnClickListener：實現ExpandableListView.OnChildClickListener接口，這里就簡單的進行Toast操作，讀者可以修改為跳轉等其他自定義功能；
自定義長按組項或子項監聽器類MyOnLongClickListener：實現AdapterView.OnItemLongClickListener接口，通過調用ExpandableListView的getPackedPositionType()方法來判斷此時長按的是組項還是子項；這里將長按組和子項分離出來，方便根據功能修改；無論是組項還是子項長按后，都調用alertModifyDialog()彈修改對話框，傳入當前項的名稱；
新增組addGroup函數：將傳遞過來的newGroupName，添加parentList中，且定義一個空的list，綁定newGroupName，將這對string和list，添加到map中；最后，調用adapter.notifyDataSetChanged()刷新列表，調用saveData()保存數據到ShareReference；
同理，新增子項到指定組addChild()，刪除指定組deleteGroup()，刪除指定子項deleteChild()，都是對parentList和map進行操作，最后刷新列表和保存數據；
修改該項名稱modifyName():通過傳遞過來childPosition進行判斷，當修改項為組項時，childPosition的值為-1，以此區分組項和子項；這里遇到一個問題，當組項提交的名稱與原名稱相同會報錯，故添加一個判斷，僅提交的名稱不同時才進行修改操作；修改的具體實現還是對parentList和map的操作，以修改組項為例，同新增組，添加一個modifyName的組，其對應的List為原來組名對應的List數據，然后再將原來的groupName組及其對應的list刪除，實現修改；最后同樣要刷新列表和保存數據；
彈修改對話框alertModifyDialog()函數：首先對自定義的dialog進行實例化，初始化標題和輸入框中的數據；調用getEditText()函數獲取輸入框實例，添加提交按鈕點擊事件，調用modifyName方法傳入當前組和子項數據，以及輸入框中提交的文本；
彈新增組對話框alertAddDialog()函數：同樣，實例化dialog，獲取輸入框控件，點擊事件中調用addGroup()方法添加數據；
保存數據saveData()函數：將parentList和map數據轉化為String類型，分別賦值，保存至ShareReference的Editor中并提交；
以上就是本文的全部內容，希望對大家的學習有所幫助。
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