Android中ExpandableList的使用2
本文介绍Android中ExpandableList的使用,在前文的基础上作了很多改进,增加了增加、删除、回调等功能。
图中的 “第一行班组号: 1 软件工程2班”是要显示的信息。
先看效果图:
首先定义一个含有ExpandableListView的Layout。还有一个是显示的文本信息。
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context=".MainActivity" > <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/hello_world" /> <ExpandableListView android:id="@+id/expandableListView1" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_alignLeft="@+id/textView1" android:layout_below="@+id/textView1" android:layout_marginTop="52dp" > </ExpandableListView> </RelativeLayout>
2、为ExpandableListView准备数据源。
ClassGroups列表,定义了所有的班级。
ClassDetails定义班级的详细信息。包括班级编号,班级名称,班级人数,以及老师。
private List<String> ClassGroups = new ArrayList<String>(); private List<List<String>> ClassDetails = new ArrayList<List<String>>(); private String[][] ClassDetailsSource = { { "20100801", "软件工程1班", "50", "王老师" }, { "20100802", "软件工程2班", "47", "理老师" }, { "20100803", "网络工程1班", "52" }, { "20100804", "计算机科学与技术" } };
通过addItem方法,初始化四个班级。
private void parepareDataSource() { for (int i = 0; i < 4; i++) { addItem("班组号:"+i, ClassDetailsSource[i]); } }
将所有的班级添加的ClassDetails中。
private void addItem(String string, String[] data) { // TODO Auto-generated method stub ClassGroups.add(string); List<String> item = new ArrayList<String>(); for (int i = 0; i < data.length; i++) { item.add(data[i]); } ClassDetails.add(item); }
3、使用BaseExpandableListAdapter绑定数据源。这个在我的上一篇文章中以及介绍过了,这里不在介绍。
@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); parepareDataSource(); tView = (TextView) findViewById(R.id.textView1); expandableListView = (ExpandableListView) findViewById(R.id.expandableListView1); expandableListView.setAdapter(new ExpandableListAdapter()); //ExpandableListView的回调函数 用于监听那个id 被expand expandableListView.setOnGroupClickListener(new OnGroupClickListener() { @Override public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) { // TODO Auto-generated method stub Toast.makeText(ExpandableList3.this, "You Click " + groupPosition + " Group", Toast.LENGTH_LONG).show(); return false; } }); expandableListView.setOnChildClickListener(new OnChildClickListener() { @Override public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) { // TODO Auto-generated method stub Toast.makeText(ExpandableList3.this, "You Click " + childPosition + " child in group" + groupPosition, Toast.LENGTH_LONG).show(); return false; } }); }
注:expandableListView.setOnGroupClickListener(new OnGroupClickListener())和expandableListView.setOnChildClickListener(new OnChildClickListener())是回调方法,等会再讲。
下面是ExpandableListAdapter的数据源形式为:
public class ExpandableListAdapter extends BaseExpandableListAdapter { @Override public boolean isChildSelectable(int groupPosition, int childPosition) { // TODO Auto-generated method stub String string = ClassGroups.get(groupPosition) + ClassDetails.get(groupPosition).get(childPosition);
tView.setText(string); return true; } @Override public boolean hasStableIds() { // TODO Auto-generated method stub return true; } @Override public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) { // TODO Auto-generated method stub LinearLayout layout = new LinearLayout(ExpandableList3.this); layout.setOrientation(0); layout.setPadding(50, 0, 0, 0); ImageView imageView = new ImageView(ExpandableList3.this); imageView.setImageResource(R.drawable.ic_launcher); layout.addView(imageView); TextView textView = getTextView(); textView.setText(getGroup(groupPosition).toString()); layout.addView(textView); return layout; } private TextView getTextView() { // TODO Auto-generated method stub AbsListView.LayoutParams lParams = new AbsListView.LayoutParams( ViewGroup.LayoutParams.FILL_PARENT, 64); TextView textView = new TextView(ExpandableList3.this); textView.setLayoutParams(lParams); textView.setPadding(20, 0, 0, 0); textView.setGravity(Gravity.LEFT | Gravity.CENTER_VERTICAL); return textView; } @Override public long getGroupId(int groupPosition) { // TODO Auto-generated method stub return groupPosition; } @Override public int getGroupCount() { // TODO Auto-generated method stub return ClassGroups.size(); } @Override public Object getGroup(int groupPosition) { // TODO Auto-generated method stub return ClassGroups.get(groupPosition); } @Override public int getChildrenCount(int groupPosition) { // TODO Auto-generated method stub return ClassDetails.get(groupPosition).size();
} @Override public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) { // TODO Auto-generated method stub TextView textView = getTextView(); textView.setText(getChild(groupPosition, childPosition).toString()); return textView; } @Override public long getChildId(int groupPosition, int childPosition) { // TODO Auto-generated method stub return childPosition; } @Override public Object getChild(int groupPosition, int childPosition) { // TODO Auto-generated method stub return ClassDetails.get(groupPosition).get(childPosition); } };
二、创建两个Menu,分别调用各自的方法,一个是创建班级dialog, 一个是创建删除Dialog. 分别对应增加班级信息和删除班级信息
@Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); menu.add(Menu.NONE, Menu.FIRST + 1, 1, "Add").setIcon( R.drawable.ic_launcher); menu.add(Menu.NONE, Menu.FIRST + 2, 2, "Delete").setIcon( R.drawable.ic_launcher); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case Menu.FIRST + 1: createAddDialog(); break; case Menu.FIRST + 2: createDeleteDialog(); break; } return false; }
1、增加的Layout add_item.xml如下:分别放了四个文本,和文本框,一个确定,一个取消按钮。
<?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" > <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="5dp" android:text="班级号" /> <EditText android:id="@+id/add_item1" android:layout_width="200dip" android:layout_height="wrap_content" android:layout_margin="5dp" /> </LinearLayout> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="5dp" android:text="班级名" /> <EditText android:id="@+id/add_item2" android:layout_width="200dip" android:layout_height="wrap_content" android:layout_margin="5dp" /> </LinearLayout> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="5dp" android:text="班级人数" /> <EditText android:id="@+id/add_item3" android:layout_width="200dip" android:layout_height="wrap_content" android:layout_margin="5dp" /> </LinearLayout> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="5dp" android:text="老师" /> <EditText android:id="@+id/add_item4" android:layout_width="200dip" android:layout_height="wrap_content" android:layout_margin="5dp" /> </LinearLayout> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <Button android:id="@+id/ok" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="5dp" android:text="ok" /> <Button android:id="@+id/cancle" android:layout_width="200dip" android:layout_height="wrap_content" android:layout_margin="5dp" android:text="cancle" /> </LinearLayout> </LinearLayout>
2、增加的代码如下:通过addItem(class_no.getText().toString(), data);方法,将添加班级信息。取消按钮时关闭当前Dialog.
private EditText class_no; private EditText class_name; private EditText stu_num; private EditText teacher; private Dialog addDialog; public void createAddDialog() { View addView = getLayoutInflater().inflate(R.layout.add_item, null); addDialog = new Dialog(this); addDialog.setContentView(addView); addDialog.setTitle("Add class dialog"); class_no = (EditText) addView.findViewById(R.id.add_item1); class_name = (EditText) addView.findViewById(R.id.add_item2); stu_num = (EditText) addView.findViewById(R.id.add_item3); teacher = (EditText) addView.findViewById(R.id.add_item4); Button ok = (Button) addView.findViewById(R.id.ok); Button cancle = (Button) addView.findViewById(R.id.cancle); ok.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub String[] data = { class_no.getText().toString(), class_name.getText().toString(), stu_num.getText().toString(), teacher.getText().toString() }; addItem(class_no.getText().toString(), data); addDialog.dismiss(); } }); cancle.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub addDialog.dismiss(); } }); addDialog.show(); }
3、增加的效果图如下:
4、同理删除的Layout为delete_item.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" > <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="删除的班组编号:" /> <EditText android:id="@+id/delete_id" android:layout_width="200dip" android:layout_height="wrap_content" /> </LinearLayout> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > <Button android:id="@+id/delete" android:layout_width="90dip" android:layout_height="wrap_content" android:text="Delete" /> <Button android:id="@+id/cancle_delete" android:layout_width="90dip" android:layout_height="wrap_content" android:text="Canlce" /> </LinearLayout> </LinearLayout>
5、 删除的代码为:输入编号: 如2, 则将班组号为2的班级所有信息删除。调用了ClassGroups.remove(i);ClassDetails.remove(i);方法。
Dialog deleteDialog; EditText delete_group_id; public void createDeleteDialog() { View deleteView = getLayoutInflater().inflate(R.layout.delete_item, null); deleteDialog = new Dialog(this); deleteDialog.setContentView(deleteView); deleteDialog.setTitle("Delete class dialog"); delete_group_id = (EditText) deleteView.findViewById(R.id.delete_id); Button ok = (Button) deleteView.findViewById(R.id.delete); Button cancle = (Button) deleteView.findViewById(R.id.cancle_delete); ok.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub String deleteId = delete_group_id.getText().toString(); if (!deleteId.equals("")) { int i = Integer.parseInt(deleteId); ClassGroups.remove(i); ClassDetails.remove(i); } deleteDialog.dismiss(); } }); cancle.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub deleteDialog.dismiss(); } }); deleteDialog.show(); }
6、删除的效果图如下:
三、回调函数的使用。
当单击组时,显示组的信息。单击子项的信息,显示组合子项的信息。如第一张图右下角显示的信息。
//ExpandableListView的回调函数 用于监听那个id 被expand expandableListView.setOnGroupClickListener(new OnGroupClickListener() { @Override public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) { // TODO Auto-generated method stub Toast.makeText(ExpandableList3.this, "You Click " + groupPosition + " Group", Toast.LENGTH_LONG).show(); return false; } }); expandableListView.setOnChildClickListener(new OnChildClickListener() { @Override public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) { // TODO Auto-generated method stub Toast.makeText(ExpandableList3.this, "You Click " + childPosition + " child in group" + groupPosition, Toast.LENGTH_LONG).show(); return false; } });
ExpandableList的使用就介绍到这里。本文也是对自己学习情况的记录,方便以后再次学习。
作者:Work Hard Work Smart
出处:http://www.cnblogs.com/linlf03/
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