Android中的多級列表的應用

看看今天實現的Android中個多級列表的功能，其實這就是一個小組件，但是如果用好了，可以實現很大的功能呢！接著，有點累，什麼都不說了，看看看實現的過程就可以了，挺簡單的！

1.看看布局文件main.xml文件

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. android:orientation="vertical"
4. android:layout_width="fill_parent"
5. android:layout_height="fill_parent"
6. android:background="@drawable/bg"
7. >
8. <TextView
9. android:layout_width="fill_parent"
10. android:layout_height="wrap_content"
11. android:text="那些上過與即將被上的大學課程:"
12. android:textColor="#FF6100"
13. android:textSize="20dp"
16. />
17. <ExpandableListView
18. android:id="@+id/elistview"
19. android:layout_width="fill_parent"
20. android:layout_height="wrap_content"
21. android:layout_marginLeft="5dp"
24. />
25. </LinearLayout>

2.接著看看主活動mainActivity.java

1. package com.wang;
3. import android.app.Activity;
4. import android.os.Bundle;
5. import android.view.ContextMenu;
6. import android.view.View;
7. import android.view.Window;
8. import android.view.WindowManager;
9. import android.view.ContextMenu.ContextMenuInfo;
10. import android.widget.ExpandableListAdapter;
11. import android.widget.ExpandableListView;
12. import android.widget.Toast;
13. import android.widget.ExpandableListView.OnChildClickListener;
14. import android.widget.ExpandableListView.OnGroupClickListener;
15. import android.widget.ExpandableListView.OnGroupCollapseListener;
16. import android.widget.ExpandableListView.OnGroupExpandListener;
18. public class MaintActivity extends Activity {
19. // 創建一個上下文菜單的方法
20. public void onCreateContextMenu(ContextMenu menu, View v,
21. ContextMenuInfo menuInfo) {
23. super.onCreateContextMenu(menu, v, menuInfo);
25. // 一個垂直滾動的兩級列表。取得菜單項
26. ExpandableListView.ExpandableListContextMenuInfo info = (ExpandableListView.ExpandableListContextMenuInfo) menuInfo;
27. // 獲得這個類型 的位置
28. int type = ExpandableListView
29. .getPackedPositionType(info.packedPosition);
30. // 取得所在組的索引
31. int group = ExpandableListView
32. .getPackedPositionGroup(info.packedPosition);
33. // 取得子菜單的索引
34. int child = ExpandableListView
35. .getPackedPositionGroup(info.packedPosition);
37. Toast.makeText(MaintActivity.this,
38. "類型 =" + type + " 分組：" + group + " 子選項：" + child,
39. Toast.LENGTH_LONG).show();
41. }
43. private ExpandableListView eListView = null;
44. private ExpandableListAdapter adapter = null;
46. @Override
47. public void onCreate(Bundle savedInstanceState) {
49. // 去除標題,
50. this.requestWindowFeature(Window.FEATURE_NO_TITLE);
51. // 取消狀態欄，充滿全屏
52. this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
53. WindowManager.LayoutParams.FLAG_FULLSCREEN);
55. super.onCreate(savedInstanceState);
56. super.setContentView(R.layout.main);
58. // 實例化組件
59. this.eListView = (ExpandableListView) findViewById(R.id.elistview);
61. // 聲明一個adapter對象
62. adapter = new myExpendableadapler(this);
63. // 設置適配器提供了數據
64. this.eListView.setAdapter(this.adapter);
66. // 　注冊一個上下文菜單顯示給定的視圖(多個視圖可以顯示上下文菜單)。
67. super.registerForContextMenu(this.eListView);
69. // 設置點擊時候觸發的事件 1，子選項點擊事件 2。父選項單擊事件 3.分組打開事件 4.分組關閉事件
70. this.eListView.setOnChildClickListener(new ChildClickListener());
71. this.eListView.setOnGroupClickListener(new GroupClickListener());
72. this.eListView.setOnGroupExpandListener(new GroupExpandListener());
73. this.eListView.setOnGroupCollapseListener(new GroupCollapseListener());
75. }
77. // /1，子選項點擊事件
78. private class ChildClickListener implements OnChildClickListener {
80. public boolean onChildClick(ExpandableListView parent, View v,
81. int groupPosition, int childPosition, long id) {
82. Toast
83. .makeText(
84. MaintActivity.this,
85. "子選項被選中,所的組：" + groupPosition + " 子選項的位置："
86. + childPosition, Toast.LENGTH_LONG).show();
87. return false;
88. }
90. }
92. // 2。父選項單擊事件
93. private class GroupClickListener implements OnGroupClickListener {
95. public boolean onGroupClick(ExpandableListView parent, View v,
96. int groupPosition, long id) {
97. Toast.makeText(MaintActivity.this, "分組選項被選中,所在組： " + groupPosition,
98. Toast.LENGTH_LONG).show();
99. return false;
100. }
102. }
104. // 3.分組打開事件
105. private class GroupExpandListener implements OnGroupExpandListener {
107. public void onGroupExpand(int groupPosition) {
108. // TODO Auto-generated method stub
109. Toast.makeText(MaintActivity.this, "打開分組,所在組：" + groupPosition,
110. Toast.LENGTH_LONG).show();
111. }
113. }
115. // 4.分組關閉事件
116. private class GroupCollapseListener implements OnGroupCollapseListener {
118. public void onGroupCollapse(int groupPosition) {
119. Toast.makeText(MaintActivity.this, "關閉分組,所在組：" + groupPosition,
120. Toast.LENGTH_LONG).show();
121. }
123. }
125. }

3.主活動的實現需要一個適配器，myExpendableadapler.java

1. package com.wang;
3. import android.content.Context;
4. import android.view.Gravity;
5. import android.view.View;
6. import android.view.ViewGroup;
7. import android.widget.AbsListView;
8. import android.widget.BaseExpandableListAdapter;
9. import android.widget.TextView;
11. public class myExpendableadapler extends BaseExpandableListAdapter {
12. // 組名稱
13. private String[] group = new String[] { "專業課", "公共課", "選修課", "選逃課" };
14. // 子選項的名字
15. private String[][] child = new String[][] {
16. { "C語言", "java程序設計基礎教程", "數據庫原理與應用", "數據結構", "linux下的嵌入式C語言編程",
17. "linux桌面應用程序設計", "計算機操作系統", "計算機組成原理" },
18. { "大學英語", "馬克思哲學原理", "形勢與政策", "ARM體系結構", "嵌入式軟件開發", "軟件工程" },
19. { "音樂鑒賞", "市場營銷", "android開發與應用", "Visual C++實用教程", "算法分析與程序設計" },
20. { "馬克思哲學原理", "形勢與政策" } };
21. private Context context = null;
23. // 構造函數
24. public myExpendableadapler(Context context) {
26. this.context = context;
27. }
29. public Object getChild(int groupPosition, int childPosition) {
31. return this.child[groupPosition][childPosition];
32. }
34. public long getChildId(int groupPosition, int childPosition) {
36. return childPosition;
37. }
39. private TextView buildTextView() {
40. //LayoutParams AbsListView擴展提供一個位置來保存視圖類型。
41. AbsListView.LayoutParams params = new AbsListView.LayoutParams(
42. ViewGroup.LayoutParams.FILL_PARENT, 40);
44. TextView textView = new TextView(this.context);
45. textView.setLayoutParams(params);
46. //大小
47. textView.setTextSize(15.0f);
48. textView.setGravity(Gravity.LEFT+3);
49. textView.setPadding(40, 8, 3, 3);
50. return textView;
51. }
53. public View getChildView(int groupPosition, int childPosition,
54. boolean isLastChild, View convertView, ViewGroup parent) {
55. TextView textView = new TextView(this.context);
56. //得到每組的子選項並轉換成字符串
57. textView.setText(this.getChild(groupPosition, childPosition).toString());
59. return textView;
60. }
61. //統計子選項的個數
62. public int getChildrenCount(int groupPosition) {
63. // TODO Auto-generated method stub
64. return this.child[groupPosition].length;
65. }
66. //得到復選項的位置
67. public Object getGroup(int groupPosition) {
68. // TODO Auto-generated method stub
69. return this.group[groupPosition];
70. }
71. //得到復選項的個數
72. public int getGroupCount() {
73. // TODO Auto-generated method stub
74. return this.group.length;
75. }
76. //得到復選項的id
77. public long getGroupId(int groupPosition) {
78. // TODO Auto-generated method stub
79. return groupPosition;
80. }
82. public View getGroupView(int groupPosition, boolean isExpanded,
83. View convertView, ViewGroup parent) {
84. // TODO Auto-generated method stub
85. TextView textView = this.buildTextView();
86. textView.setText(this.getGroup(groupPosition).toString());
87. return textView;
88. }
89. //是否子選項和父選項id是穩定在改變底層數據。
90. public boolean hasStableIds() {
91. // TODO Auto-generated method stub
92. return true;
93. }
94. //p判斷子選項是否可以選擇
95. public boolean isChildSelectable(int groupPosition, int childPosition) {
96. // TODO Auto-generated method stub
97. return true;
98. }
100. }

4.接著就可以看看實現的效果了：