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。