将数据加载到ExpandableListView中 [英] Load data into an ExpandableListView
本文介绍了将数据加载到ExpandableListView中的处理方法，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
我正在寻找一种将数据加载到Expandale列表视图中的方法，我的输出类似于下面的图片之一
I am searching for a way to load data into an Expandale List View, the output I want to resemble the one of the picture attached here In order this to be done dynamically, is it better to be read from a csv? Or to create a DB? Furthermore, on a sub-item press, I want a ScrollView to appear.
这是到目前为止的代码: 活动的布局:
Here is the code so far: The layout of the activity:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<ExpandableListView
android:id= "@+id/android:list"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<TextView
android:id="@+id/android:empty"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</LinearLayout>
The itemlayout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView android:id="@+id/grp_child"
android:paddingLeft="50dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
子项目:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView android:id="@+id/row_name"
android:paddingLeft="50dp"
android:focusable="false"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
在活动中，到目前为止，我已经使用一些教程对一些值进行了硬编码:
In the activity, I have hardcoded some values so far, using some tutorials I came across:
public void onCreate(Bundle savedInstanceState) {
try{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_photographers);
SimpleExpandableListAdapter expListAdapter =
new SimpleExpandableListAdapter(
this,
createGroupList(),
R.layout.group_row,
new String[] { "Group Item" },
new int[] { R.id.row_name },
createChildList(),
R.layout.child_row,
new String[] {"Sub Item"},
new int[] { R.id.grp_child}
);
setListAdapter( expListAdapter );
}catch(Exception e){
System.out.println("Errrr +++ " + e.getMessage());
}
}
/* Creating the Hashmap for the row */
@SuppressWarnings("unchecked")
private List createGroupList() {
ArrayList result = new ArrayList();
for( int i = 0 ; i < 15 ; ++i ) { // 15 groups........
HashMap m = new HashMap();
m.put( "Group Item","Group Item " + i ); // the key and it's value.
result.add( m );
}
return (List)result;
}
@SuppressWarnings("unchecked")
private List createChildList() {
ArrayList result = new ArrayList();
for( int i = 0 ; i < 15 ; ++i ) { // this -15 is the number of groups(Here it's fifteen)
/* each group need each HashMap-Here for each group we have 3 subgroups */
ArrayList secList = new ArrayList();
for( int n = 0 ; n < 3 ; n++ ) {
HashMap child = new HashMap();
child.put( "Sub Item", "Sub Item " + n );
secList.add( child );
}
result.add( secList );
}
return result;
}
public void onContentChanged () {
System.out.println("onContentChanged");
super.onContentChanged();
}
/* This function is called on each child click */
public boolean onChildClick( ExpandableListView parent, View v, int groupPosition,int childPosition,long id) {
System.out.println("Inside onChildClick at groupPosition = " + groupPosition +" Child clicked at position " + childPosition);
return true;
}
/* This function is called on expansion of the group */
public void onGroupExpand (int groupPosition) {
try{
System.out.println("Group expanding Listener => groupPosition = " + groupPosition);
}catch(Exception e){
System.out.println(" groupPosition Errrr +++ " + e.getMessage());
}
}
我想知道将要显示的数据存储在单独的csv文件中是否一个好主意(一个存储项的数据，一个存储子项，一个存储ScrollView中的额外信息)，以便id-s进行标识并使用OpenCSVReader直接从CSV中读取?
I am wondering if it is a good idea to store the data I want to show in separate csv files (one storing the data for the items, one for the subitems. one for the extra information in the ScrollView), to have id-s for identification and to directly read from the CSVs with the OpenCSVReader?
我将不胜感激任何建议， 谢谢
I would appreciate any pieces of advice, Thanks
推荐答案
为可扩展listView创建适配器.像这样
create adapter for your expandable listView. like that
public class ExpandableAdapter extends BaseExpandableListAdapter {
private final Context context;
private final List<Menu> parentObjects;
public ExpandableAdapter(Context context, ArrayList<Menu> parentObjects) {
this.context = context;
this.parentObjects = parentObjects;
}
@Override
public int getGroupCount() {
return parentObjects.size();
}
@Override
public int getChildrenCount(int i) {
return parentObjects.get(i).childMenu.size();
}
@Override
public Menu getGroup(int i) {
return parentObjects.get(i);
}
@Override
public Menu.ChildMenu getChild(int i, int i2) {
return parentObjects.get(i).childMenu.get(i2);
}
@Override
public long getGroupId(int i) {
return i;
}
@Override
public long getChildId(int i, int i2) {
return 0;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public View getGroupView(int i, boolean b, View view, ViewGroup viewGroup) {
Menu currentParent = parentObjects.get(i);
if (view == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context
.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.navdrawer_parent_item, viewGroup,false);
}
ImageView imageViewIndicator = (ImageView) view.findViewById(R.id.imageViewNav);
if (getChildrenCount(i) == 0)
imageViewIndicator.setVisibility(View.GONE);
else
imageViewIndicator.setVisibility(View.VISIBLE);
TextView textViewNavMenuName = (TextView) view.findViewById(R.id.textViewNavParentMenuName);
ImageView imageViewIcon = (ImageView) view.findViewById(R.id.imageViewIcon);
String base64 = currentParent.getImage();
if (base64 != null && !base64.equals("")) {
byte[] imageAsBytes = Base64.decode(currentParent.getImage().getBytes(), Base64
.DEFAULT);
imageViewIcon.setImageBitmap(BitmapFactory.decodeByteArray(imageAsBytes, 0,
imageAsBytes.length));
} else
imageViewIcon.setImageResource(R.drawable.ic_action_android);
textViewNavMenuName.setText(currentParent.getMenuName());
return view;
}
@Override
public View getChildView(int groupPosition, int childPosition, boolean b, View view,
ViewGroup viewGroup) {
Menu currentChild = getGroup(groupPosition);
if (view == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context
.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.navdrawer_child_item, viewGroup,false);
}
View divider = view.findViewById(R.id.divider);
if (b)
divider.setVisibility(View.VISIBLE);
else
divider.setVisibility(View.GONE);
TextView textViewNavMenuName = (TextView) view.findViewById(R.id.textViewNavChildMenuName);
textViewNavMenuName.setText(currentChild.childMenu.get(childPosition).getMenuName());
return view;
}
@Override
public boolean isChildSelectable(int i, int i2) {
return true;
}
}
以及
public class Menu {
private int AssociatedApp;
private String MenuName;
private String NavigateURL;
private String ActivityName;
private String Image;
private int MenuID;
public ArrayList<ChildMenu> childMenu;
public ArrayList<ChildMenu> getChildMenu() {
return childMenu;
}
public void setChildMenu(ArrayList<ChildMenu> childMenu) {
this.childMenu = childMenu;
}
public int getAssociatedApp() {
return AssociatedApp;
}
public void setAssociatedApp(int associatedApp) {
AssociatedApp = associatedApp;
}
public String getMenuName() {
return MenuName;
}
public void setMenuName(String menuName) {
MenuName = menuName;
}
public String getNavigateURL() {
return NavigateURL;
}
public void setNavigateURL(String navigateURL) {
NavigateURL = navigateURL;
}
public String getActivityName() {
return ActivityName;
}
public void setActivityName(String activityName) {
ActivityName = activityName;
}
public String getImage() {
return Image;
}
public void setImage(String image) {
Image = image;
}
public Menu() {
}
public int getMenuID() {
return MenuID;
}
public class ChildMenu {
private int AssociatedApp;
private String MenuName;
private String NavigateURL;
private String ActivityName;
private String Image;
private int MenuID;
public ChildMenu(String menuName, String activityName) {
this.MenuName = menuName;
this.ActivityName=activityName;
}
public ChildMenu() {
}
public int getAssociatedApp() {
return AssociatedApp;
}
public void setAssociatedApp(int associatedApp) {
AssociatedApp = associatedApp;
}
public String getMenuName() {
return MenuName;
}
public void setMenuName(String menuName) {
MenuName = menuName;
}
public String getNavigateURL() {
return NavigateURL;
}
public void setNavigateURL(String navigateURL) {
NavigateURL = navigateURL;
}
public String getActivityName() {
return ActivityName;
}
public void setActivityName(String activityName) {
ActivityName = activityName;
}
public String getImage() {
return Image;
}
public void setImage(String image) {
Image = image;
}
public int getMenuID() {
return MenuID;
}
}
}
好吧，现在您可以使用数据创建菜单，并使用可扩展的列表视图进行绑定
ok now you can create your menu with data and bindwith expandable listview
elv = (ExpandableListView)findViewById(R.id.elv);
elv.setOnGroupExpandListener(onGroupExpandListenser);
MyExpandableAdapter adapter = new MyExpandableAdapter(this, getData());//where getData() will return list of data.
elv.setAdapter(adapter);
父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">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="match_parent"
android:paddingBottom="12dp"
android:paddingLeft="12dp"
android:paddingTop="12dp">
<ImageView
android:contentDescription="@string/app_name"
android:id="@+id/imageViewIcon"
android:layout_width="35dp"
android:layout_height="35dp"
android:layout_alignParentLeft="true"
android:layout_margin="4dp"
/>
<TextView
android:id="@+id/textViewNavParentMenuName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_centerVertical="true"
android:layout_toLeftOf="@+id/imageViewNav"
android:layout_toRightOf="@+id/imageViewIcon"
android:padding="10dp"
android:textSize="15sp"/>
<ImageView
android:contentDescription="@string/app_name"
android:id="@+id/imageViewNav"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_margin="4dp"
android:src="@drawable/ic_action_more_nav"
/>
</RelativeLayout>
<include
layout="@layout/divider"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
</LinearLayout>
子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="wrap_content"
android:gravity="center_vertical"
android:orientation="vertical">
<TextView
android:id="@+id/textViewNavChildMenuName"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="45dp"
android:gravity="center_vertical"
android:text="TextView"
android:padding="16dp"/>
<include
layout="@layout/divider"
android:layout_width="match_parent"
android:layout_height="fill_parent"/>
</LinearLayout>
像这样为可扩展listView添加侦听器. groupExpandlistener用于在打开一个群组时对其他群组进行整理
adding listener for expandable listView like this. groupExpandlistener is used for collasping other groups while open one
private int lastExpandedPosition = -1;
用于设置侦听器
elv.setOnChildClickListener(new DrawerItemClickListener());
elv.setOnGroupClickListener(new DrawerItemClickListener());
elv.setOnGroupExpandListener(new DrawerItemClickListener());
private class DrawerItemClickListener implements ExpandableListView.OnChildClickListener,
ExpandableListView.OnGroupClickListener, ExpandableListView.OnGroupExpandListener {
@Override
public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int
childPosition, long id) {
selectItem(childPosition, navigationConfig.getBaseExpandableListAdapter
().getChild
(groupPosition, childPosition));
return true;
}
@Override
public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
selectItem(groupPosition, navigationConfig.getBaseExpandableListAdapter
().getGroup
(groupPosition));
return false;
}
@Override
public void onGroupExpand(int groupPosition) {
if (lastExpandedPosition != -1
&& groupPosition != lastExpandedPosition) {
expandableListView.collapseGroup(lastExpandedPosition);
}
lastExpandedPosition = groupPosition;
}
}
用于将示例数据与getData()绑定.注意在模型类中创建构造函数，如getData()
for sample data use to bind with getData(). note create constructor in model class as given in getData()
//Sample data for expandable list view.
public List<Menu> getData()
{
List<Menu> parentObjects = new ArrayList<Menu>();
for (int i = 0; i<20; i++)
{
parentObjects.add(new Menu("Mother " +i, "Father " +i, "Header " + i, "Footer " +i, getChildren(i)));
}
return parentObjects;
}
private List<Menu.ChildMenu> getChildren(int childCount)
{
List<Menu.ChildMenu> childObjects = new ArrayList<Menu.ChildMenu>();
for (int i =0; i<childCount; i++)
{
childObjects.add(new Menu.ChildMenu("Child " + (i+1), 10 +i ));
}
return childObjects;
}
这篇关于将数据加载到ExpandableListView中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IT屋！
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