本文介绍了使用组和子复选框创建可扩展列表视图的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我想创建一个可扩展的列表视图，其中包含组中以及子项中的复选框。我想要的是，用户可以检查组以便选择组中的所有孩子，或者用户可以在可扩展列表视图下选择特定项目。
I want to create an expandable listview with checkboxes present in the groups as well as the children. What I want is, the user may check the group in order to select all the children in the group, or the user may select a particular item under the expandable listview.
这个概念在我们的asp.net网站中以树视图的形式运行。我附上了正在运行的网站的一些屏幕：
This concept is running in our asp.net website as a tree view. I am attaching some screens of the running website:
未展开群组的Treeview
Treeview已选择完整群组
在群组下选择特定儿童的Treeview
Treeview with particular children selected under group
主类：
The main class:
public class MainActivity extends Activity {
public class MainActivity extends Activity {
ExpandableListAdapter listAdapter;
ExpandableListView expListView;
List<String> listDataHeader;
HashMap<String, List<String>> listDataChild;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// get the listview
expListView = (ExpandableListView) findViewById(R.id.lvExp);
// preparing list data
prepareListData();
listAdapter = new ExpandableListAdapter(this, listDataHeader, listDataChild);
// setting list adapter
expListView.setAdapter(listAdapter);
// Listview Group click listener
expListView.setOnGroupClickListener(new OnGroupClickListener() {
@Override
public boolean onGroupClick(ExpandableListView parent, View v,
int groupPosition, long id) {
// Toast.makeText(getApplicationContext(),
// "Group Clicked " + listDataHeader.get(groupPosition),
// Toast.LENGTH_SHORT).show();
return false;
}
});
// Listview Group expanded listener
expListView.setOnGroupExpandListener(new OnGroupExpandListener() {
@Override
public void onGroupExpand(int groupPosition) {
Toast.makeText(getApplicationContext(),
listDataHeader.get(groupPosition) + " Expanded",
Toast.LENGTH_SHORT).show();
}
});
// Listview Group collasped listener
expListView.setOnGroupCollapseListener(new OnGroupCollapseListener() {
@Override
public void onGroupCollapse(int groupPosition) {
Toast.makeText(getApplicationContext(),
listDataHeader.get(groupPosition) + " Collapsed",
Toast.LENGTH_SHORT).show();
}
});
// Listview on child click listener
expListView.setOnChildClickListener(new OnChildClickListener() {
@Override
public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
// TODO Auto-generated method stub
Toast.makeText(
getApplicationContext(),
listDataHeader.get(groupPosition)
+ " : "
+ listDataChild.get(
listDataHeader.get(groupPosition)).get(
childPosition), Toast.LENGTH_SHORT)
.show();
return false;
}
});
}
/*
* Preparing the list data
*/
private void prepareListData() {
listDataHeader = new ArrayList<String>();
listDataChild = new HashMap<String, List<String>>();
// Adding child data
listDataHeader.add("Top 250");
listDataHeader.add("Now Showing");
listDataHeader.add("Coming Soon..");
// Adding child data
List<String> top250 = new ArrayList<String>();
top250.add("The Shawshank Redemption");
top250.add("The Godfather");
top250.add("The Godfather: Part II");
top250.add("Pulp Fiction");
top250.add("The Good, the Bad and the Ugly");
top250.add("The Dark Knight");
top250.add("12 Angry Men");
List<String> nowShowing = new ArrayList<String>();
nowShowing.add("The Conjuring");
nowShowing.add("Despicable Me 2");
nowShowing.add("Turbo");
nowShowing.add("Grown Ups 2");
nowShowing.add("Red 2");
nowShowing.add("The Wolverine");
List<String> comingSoon = new ArrayList<String>();
comingSoon.add("2 Guns");
comingSoon.add("The Smurfs 2");
comingSoon.add("The Spectacular Now");
comingSoon.add("The Canyons");
comingSoon.add("Europa Report");
listDataChild.put(listDataHeader.get(0), top250); // Header, Child data
listDataChild.put(listDataHeader.get(1), nowShowing);
listDataChild.put(listDataHeader.get(2), comingSoon);
}
}
ExpandableListAdapter / p>
The ExpandableListAdapter:
public class ExpandableListAdapter extends BaseExpandableListAdapter {
private Context _context;
private List<String> _listDataHeader; // header titles
// child data in format of header title, child title
private HashMap<String, List<String>> _listDataChild;
public ExpandableListAdapter(Context context, List<String> listDataHeader,
HashMap<String, List<String>> listChildData) {
this._context = context;
this._listDataHeader = listDataHeader;
this._listDataChild = listChildData;
}
@Override
public Object getChild(int groupPosition, int childPosititon) {
return this._listDataChild.get(this._listDataHeader.get(groupPosition))
.get(childPosititon);
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
@Override
public View getChildView(int groupPosition, final int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
final String childText = (String) getChild(groupPosition, childPosition);
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) this._context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.list_item, null);
}
TextView txtListChild = (TextView) convertView
.findViewById(R.id.lblListItem);
txtListChild.setText(childText);
return convertView;
}
@Override
public int getChildrenCount(int groupPosition) {
return this._listDataChild.get(this._listDataHeader.get(groupPosition))
.size();
}
@Override
public Object getGroup(int groupPosition) {
return this._listDataHeader.get(groupPosition);
}
@Override
public int getGroupCount() {
return this._listDataHeader.size();
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
String headerTitle = (String) getGroup(groupPosition);
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) this._context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.list_group, null);
}
TextView lblListHeader = (TextView) convertView
.findViewById(R.id.lblListHeader);
lblListHeader.setTypeface(null, Typeface.BOLD);
lblListHeader.setText(headerTitle);
return convertView;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
activity_main.xml ：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:background="#f4f4f4" >
<ExpandableListView
android:id="@+id/lvExp"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:cacheColorHint="#00000000"/>
</LinearLayout>
list_group.xml ：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="8dp"
android:background="#000000">
<TextView
android:id="@+id/lblListHeader"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"
android:textSize="17dp"
android:textColor="#f9f93d" />
</LinearLayout>
list_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="55dip"
android:orientation="vertical" >
<TextView
android:id="@+id/lblListItem"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="17dip"
android:paddingTop="5dp"
android:paddingBottom="5dp"
android:textColor="#000000"
android:paddingLeft="?android:attr/expandableListPreferredChildPaddingLeft" />
</LinearLayout>
我已经创建了一个简单的可扩展列表视图，现在我想包括复选框其他控件足以满足我的要求。我已经搜索了一个可靠的教程，但我找不到一个。
I have already created a simple expandable listview, now I want to include the checkboxes or any other controls to suffice my requirement. I have googled for a sutaible tutorial but I was unable to find one. Please help me with one if possible.
推荐答案
要做到这一点你需要包括 boolean 在每个对象中，或在适配器中创建两个列表视图（组和项目）将包含所选项目。
To do this you will need to include boolean flag in each object, or in you adapter create two list views (for groups and items) that will contain selected items.
我宁愿添加 boolean 如下：
class Group{ ...
boolean isSelected;
}
class Item { ...
boolean isSelected;
}
然后在 Adapter getViews（）方法：
getItemView(...){
...
itemHolder.checkbox.setSelected(item.isSelected)
}
getGroupView(...){
...
groupHolder.checkbox.setSelected(group.isSelected)
//add lisener
itemHolder.checkbox.setOnCheckedChangeListener(lisener);
}
在群组检查中，您可以执行以下操作：
And on group check you can do something like this :
void selectGroup(Group group){
for(Item item: group.getItems()){
item.isSelected = true;
}
//update your list
notifiDataSetChanged();
}
这就是你需要的
UPDATE ：
- Android Developers - UI
- Android Holder Pattern
这篇关于使用组和子复选框创建可扩展列表视图的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！