本文介绍了ExpandableListView和NavigationDrawer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
我有一个pretty的奇怪的问题。我的逻辑很简单，我的应用程序使用了 NavigationDrawer 主应用程序的导航，并且由于可用选项的复杂性，我想用一个 ExpandableListViev 嵌套一些导航项目。
问题过于简单：在抽屉里的物品装载清单;然而，他们不展开显示孩子。
问题是否有任何理由会不会扩大？我应该使用一个不同的UI小部件呢？
若干注记：我添加了相同的code在不同的活动，但不是主持 ExpandableListViev 抽屉，我有它添加一个简单的的LinearLayout 作为唯一的元素，它的也工作得很好有。
我的布局为活动：
＆LT; android.support.v4.widget.DrawerLayout
的xmlns：机器人=http://schemas.android.com/apk/res/android
的xmlns：工具=http://schemas.android.com/tools
机器人：ID =@ + ID / drawer_layout
机器人：layout_width =match_parent
机器人：layout_height =match_parent
工具：上下文=MainActivity。＆GT;
＆LT;的FrameLayout
机器人：ID =@ + ID / content_frame
机器人：layout_width =match_parent
机器人：layout_height =match_parent/＆GT;
＆LT; ExpandableListView
机器人：ID =@ + ID / left_drawer
机器人：layout_width =240dp
机器人：layout_height =match_parent
机器人：layout_gravity =开始
机器人：背景=@色/ secondary_color_holo/＆GT;
＆LT; /android.support.v4.widget.DrawerLayout>
该活动code：
私人DrawerLayout mDrawerLayout;
私人ExpandableListView mDrawerList;
私人ExpandableDrawerAdapter mDrawerAdapter;
@覆盖
保护无效的onCreate（包savedInstanceState）{
super.onCreate（savedInstanceState）;
的setContentView（R.layout.activity_main）;
mDrawerLayout =（DrawerLayout）findViewById（R.id.drawer_layout）;
mDrawerList =（ExpandableListView）findViewById（R.id.left_drawer）;
//设置抽屉的列表视图项，然后单击监听器
mDrawerAdapter =新ExpandableDrawerAdapter（本）;
mDrawerList.setAdapter（mDrawerAdapter）;
mDrawerList.setOnGroupClickListener（新DrawerGroupClickListener（））;
mDrawerList.setOnChildClickListener（新DrawerChildClickListener（））;
}
最后一个非常简单的适配器：
公共类ExpandableDrawerAdapter扩展BaseExpandableListAdapter {
私有静态最终诠释CAMPAIGNS = 0;
私有静态最终诠释CONVERSIONS = 1;
私有静态最终诠释我的帐户= 2;
私人LayoutInflater mInflater;
私有String [] mainNavItems，campaignNavItems，myAccountNavItems;
公共ExpandableDrawerAdapter（活动范围内）{
this.mInflater =（LayoutInflater）context.getSystemService（Context.LAYOUT_INFLATER_SERVICE）;
this.mainNavItems = context.getResources（）getStringArray（R.array.main_nav_items）。
this.campaignNavItems = context.getResources（）getStringArray（R.array.campaigns_nav_items）。
this.myAccountNavItems = context.getResources（）getStringArray（R.array.my_account_nav_items）。
}
公共对象getChild（INT groupPosition，诠释childPosition）{
开关（groupPosition）{
案例CAMPAIGNS：
返回campaignNavItems [childPosition]
案例我的帐户：
返回myAccountNavItems [childPosition]
默认：
返回 ;
}
}
众长getChildId（INT groupPosition，诠释childPosition）{
返回childPosition;
}
公共查看getChildView（最终诠释groupPosition，最终诠释childPosition，
布尔isLastChild，查看convertView，ViewGroup中父）{
如果（convertView == NULL）{
convertView = mInflater.inflate（R.layout.drawer_child_list_item，NULL）;
}
TextView的childText =（TextView中）convertView.findViewById（R.id.drawer_child_list_item_text）;
childText.setText（（字符串）getChild（groupPosition，childPosition））;
返回convertView;
}
公众诠释getChildrenCount（INT groupPosition）{
开关（groupPosition）{
案例CAMPAIGNS：
Constants.logMessage（为集团的立场孩子：+ groupPosition +是：+ campaignNavItems.length）;
返回campaignNavItems.length;
大小写转换：
Constants.logMessage（为集团的立场孩子：+ groupPosition +是：+ 0）;
返回0;
案例我的帐户：
Constants.logMessage（为集团的立场孩子：+ groupPosition +是：+ myAccountNavItems.length）;
返回myAccountNavItems.length;
默认：
返回0;
}
}
公共对象getGroup（INT groupPosition）{
返回mainNavItems [groupPosition]
}
公众诠释getGroupCount（）{
返回mainNavItems.length;
}
众长getGroupId（INT groupPosition）{
返回groupPosition;
}
公共查看getGroupView（INT groupPosition，布尔isExpanded，
查看convertView，ViewGroup中父）{
如果（convertView == NULL）{
convertView = mInflater.inflate（R.layout.drawer_list_item，
空值）;
}
TextView的groupText =（TextView中）convertView.findViewById（R.id.drawer_list_item_text）;
groupText.setText（（字符串）getGroup（groupPosition））;
返回convertView;
}
公共布尔hasStableIds（）{
返回true;
}
公共布尔isChildSelectable（INT groupPosition，诠释childPosition）{
返回true;
}
}
解决方案
正如我在我的评论说，请确保您返回假从 DrawerGroupClickListener 您在 ExpandableListView 设置。如果返回真从听者的 onGroupClick（）回调，这将阻止折叠/展开行动，该事件是<一个href="http://grep$c$c.com/file/repository.grep$c$c.com/java/ext/com.google.android/android/4.3_r2.1/android/widget/ExpandableListView.java#ExpandableListView.handleItemClick%28android.view.View,int,long%29">considered处理。
I am having a pretty strange issue. My logic is simple, my app uses a NavigationDrawer for main application navigation, and due to the complexity of the options available, I want to use an ExpandableListViev to nest some navigation items.
The issue? Simple too: The list of items loads on the drawer; however, they don't expand to show the children.
The Question Is there any reason it wouldn't expand? Should I use a different UI widget for this?
Some Notes: I added the same code on a different Activity, but instead of hosting the ExpandableListViev on the drawer, I had it added on a simple LinearLayout as the only element, and it does work well there.
My Layout for the Activity:
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<FrameLayout
android:id="@+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<ExpandableListView
android:id="@+id/left_drawer"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="@color/secondary_color_holo"/>
</android.support.v4.widget.DrawerLayout>
The Activity code:
private DrawerLayout mDrawerLayout;
private ExpandableListView mDrawerList;
private ExpandableDrawerAdapter mDrawerAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerList = (ExpandableListView) findViewById(R.id.left_drawer);
// set up the drawer's list view with items and click listener
mDrawerAdapter = new ExpandableDrawerAdapter(this);
mDrawerList.setAdapter(mDrawerAdapter);
mDrawerList.setOnGroupClickListener(new DrawerGroupClickListener());
mDrawerList.setOnChildClickListener(new DrawerChildClickListener());
}
And finally a very simple adapter:
public class ExpandableDrawerAdapter extends BaseExpandableListAdapter {
private static final int CAMPAIGNS = 0;
private static final int CONVERSIONS = 1;
private static final int MYACCOUNT = 2;
private LayoutInflater mInflater;
private String[] mainNavItems, campaignNavItems, myAccountNavItems;
public ExpandableDrawerAdapter (Activity context) {
this.mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
this.mainNavItems = context.getResources().getStringArray(R.array.main_nav_items);
this.campaignNavItems = context.getResources().getStringArray(R.array.campaigns_nav_items);
this.myAccountNavItems = context.getResources().getStringArray(R.array.my_account_nav_items);
}
public Object getChild(int groupPosition, int childPosition) {
switch (groupPosition) {
case CAMPAIGNS:
return campaignNavItems[childPosition];
case MYACCOUNT:
return myAccountNavItems[childPosition];
default:
return "";
}
}
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
public View getChildView(final int groupPosition, final int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = mInflater.inflate(R.layout.drawer_child_list_item, null);
}
TextView childText = (TextView) convertView.findViewById(R.id.drawer_child_list_item_text);
childText.setText((String) getChild(groupPosition, childPosition));
return convertView;
}
public int getChildrenCount(int groupPosition) {
switch (groupPosition) {
case CAMPAIGNS:
Constants.logMessage("Children for group position: " + groupPosition + " are: " + campaignNavItems.length);
return campaignNavItems.length;
case CONVERSIONS:
Constants.logMessage("Children for group position: " + groupPosition + " are: " + 0);
return 0;
case MYACCOUNT:
Constants.logMessage("Children for group position: " + groupPosition + " are: " + myAccountNavItems.length);
return myAccountNavItems.length;
default:
return 0;
}
}
public Object getGroup(int groupPosition) {
return mainNavItems[groupPosition];
}
public int getGroupCount() {
return mainNavItems.length;
}
public long getGroupId(int groupPosition) {
return groupPosition;
}
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = mInflater.inflate(R.layout.drawer_list_item,
null);
}
TextView groupText = (TextView) convertView.findViewById(R.id.drawer_list_item_text);
groupText.setText((String) getGroup(groupPosition));
return convertView;
}
public boolean hasStableIds() {
return true;
}
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
解决方案
As I said in my comment, make sure that you return false from the DrawerGroupClickListener that you set on the ExpandableListView. If you return true from the listener's onGroupClick() callback this will block the collapse/expand action as the event is considered handled.
这篇关于ExpandableListView和NavigationDrawer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！