ExpandableList查看未使用ExpandableListActivity [英] ExpandableList View not using ExpandableListActivity
问题描述
由于我没有足够的信誉分，previous问题发表意见呢，我不得不创建一个新的。我需要一个可扩展的列表视图并没有占据整个活动，所以我用这个例子来做到这一点不ExpandableListActivity：
我稍微修改code：
公共类主要扩展活动{
ExpandableListView LV;
@覆盖
公共无效的onCreate（包savedInstanceState）{
super.onCreate（savedInstanceState）;
的setContentView（R.layout.expandable_list）;
LV =（ExpandableListView）this.findViewById（R.id.expandableListView1）;
MyExpandableListAdapter expandableAdapter =新MyExpandableListAdapter（）;
lv.setAdapter（expandableAdapter）;
}
类MyExpandableListAdapter扩展BaseExpandableListAdapter {
//样本数据集。孩子们[I]包含儿童（字符串[]）团体[1]。
私有String []组= {人名称，狗名，名猫，鱼名};
私有String [] []孩子= {
{阿诺德，巴里，查克，大卫}，
{王牌，强盗，双查，平分}，
{蓬松，的Snuggles}，
{戈尔迪，泡}
};
公共对象getChild（INT groupPosition，诠释childPosition）{
返回儿[groupPosition] [childPosition]
}
众长getChildId（INT groupPosition，诠释childPosition）{
返回childPosition;
}
公众诠释getChildrenCount（INT groupPosition）{
返回儿[groupPosition] .length;
}
公众的TextView getGenericView（）{
//布局参数ExpandableListView
AbsListView.LayoutParams LP =新AbsListView.LayoutParams（
ViewGroup.LayoutParams.MATCH_PARENT，64）;
TextView中的TextView =新的TextView（Main.this）;
textView.setLayoutParams（LP）;
//中心的文本垂直
textView.setGravity（Gravity.CENTER_VERTICAL | Gravity.LEFT）;
//设置文本的起始位置
textView.setPadding（36，0，0，0）;
返回的TextView;
}
公共查看getChildView（INT groupPosition，诠释childPosition，布尔isLastChild，
查看convertView，ViewGroup中父）{
TextView中的TextView = getGenericView（）;
textView.setText（getChild（groupPosition，childPosition）的ToString（））;
返回的TextView;
}
公共对象getGroup（INT groupPosition）{
返回组[groupPosition]
}
公众诠释getGroupCount（）{
返回groups.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）{
TextView中的TextView = getGenericView（）;
textView.setText（getGroup（groupPosition）的ToString（））;
返回的TextView;
}
公共布尔hasStableIds（）{
返回true;
}
公共布尔isChildSelectable（INT groupPosition，诠释childPosition）{
返回true;
}
}
}
这工作得很好，但要使其更加坚固，我想分开在code创建的XML文件（这是个好主意吗？）这是我碰到一些FC的问题textViews。
group_row.xml：
＆LT; XML版本=1.0编码=UTF-8＆GT？;
＆LT; LinearLayout中的xmlns：机器人=http://schemas.android.com/apk/res/android
机器人：方向=横向
机器人：layout_width =FILL_PARENT
机器人：layout_height =FILL_PARENT＆GT;
＆LT; TextView的机器人：ID =@ + ID / row_name
机器人：以下属性来=50像素
机器人：TEXTSIZE =20像素
机器人：TEXTSTYLE =正常
机器人：layout_width =320px的
机器人：layout_height =WRAP_CONTENT/＆GT;
＆LT; / LinearLayout中＆GT;
和我在java文件上面的改变这样的：
公开查看getGroupView（INT groupPosition，布尔isExpanded，查看convertView，ViewGroup中父）{
TextView的parentRow =（TextView中）findViewById（R.id.row_name）;
parentRow.setText（getGroup（groupPosition）的ToString（））;
返回parentRow;
}
我也试图消除的LinearLayout包装，但没有任何修复。谁能告诉我为什么我的XML视图不工作？谢谢你。
编辑： 由于弗洛，新的code表示正在使用教程：
group_row.xml：
＆LT; XML版本=1.0编码=UTF-8＆GT？;
＆LT; TextView中的xmlns：机器人=http://schemas.android.com/apk/res/android
机器人：ID =@ + ID /组名
机器人：以下属性来=50dp
机器人：TEXTSIZE =30sp
机器人：TEXTSTYLE =正常
机器人：layout_height =WRAP_CONTENT/＆GT;
主营：
公开查看getGroupView（INT groupPosition，布尔isExpanded，查看convertView，ViewGroup中父）{
查看parentView = convertView;
如果（parentView == NULL）{
LayoutInflater VI =（LayoutInflater）getSystemService（Context.LAYOUT_INFLATER_SERVICE）;
parentView = vi.inflate（R.layout.group_row，NULL）;
}
TextView的parentText =（TextView中）parentView.findViewById（R.id.group_name）;
如果（parentText！= NULL）{
parentText.setText（getGroup（groupPosition）的ToString（））;
}
返回parentText;
}
您实现getGroupView（）方法是错误的。目前，在活动的布局你在寻找一个元素与元素 R.id.row_name 不存在。我猜行 parentRow.setText（getGroup（groupPosition）的ToString（））; 抛出一个异常，如 parentRow 是空值。
正确执行方法，从一个XML文件中的自定义行布局是夸大这种布局。请查看本教程。它是为正常列表视图和适配器，但膨胀的行的概念布局它是相同的。
Because I don't have enough reputation points to comment on previous questions yet, I had to create a new one. I needed an expandable list view that didn't take up the entire activity so I used this example to do it without ExpandableListActivity:
ExpandableList View don't expand
My slightly modified code:
public class Main extends Activity {
ExpandableListView lv;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.expandable_list);
lv = (ExpandableListView) this.findViewById(R.id.expandableListView1);
MyExpandableListAdapter expandableAdapter = new MyExpandableListAdapter();
lv.setAdapter(expandableAdapter);
}
class MyExpandableListAdapter extends BaseExpandableListAdapter {
// Sample data set. children[i] contains the children (String[]) for groups[i].
private String[] groups = { "People Names", "Dog Names", "Cat Names", "Fish Names" };
private String[][] children = {
{ "Arnold", "Barry", "Chuck", "David" },
{ "Ace", "Bandit", "Cha-Cha", "Deuce" },
{ "Fluffy", "Snuggles" },
{ "Goldy", "Bubbles" }
};
public Object getChild(int groupPosition, int childPosition) {
return children[groupPosition][childPosition];
}
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
public int getChildrenCount(int groupPosition) {
return children[groupPosition].length;
}
public TextView getGenericView() {
// Layout parameters for the ExpandableListView
AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT, 64);
TextView textView = new TextView(Main.this);
textView.setLayoutParams(lp);
// Center the text vertically
textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
// Set the text starting position
textView.setPadding(36, 0, 0, 0);
return textView;
}
public View getChildView(int groupPosition, int childPosition, boolean isLastChild,
View convertView, ViewGroup parent) {
TextView textView = getGenericView();
textView.setText(getChild(groupPosition, childPosition).toString());
return textView;
}
public Object getGroup(int groupPosition) {
return groups[groupPosition];
}
public int getGroupCount() {
return groups.length;
}
public long getGroupId(int groupPosition) {
return groupPosition;
}
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
TextView textView = getGenericView();
textView.setText(getGroup(groupPosition).toString());
return textView;
}
public boolean hasStableIds() {
return true;
}
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
}
This works fine, but to make it more robust, I wanted to separate the textViews created in code to xml files (This is a good idea right?) This is where I run into some FC issues.
group_row.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView android:id="@+id/row_name"
android:paddingLeft="50px"
android:textSize="20px"
android:textStyle="normal"
android:layout_width="320px"
android:layout_height="wrap_content"/>
</LinearLayout>
And I changed this in the java file above:
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
TextView parentRow = (TextView) findViewById(R.id.row_name);
parentRow.setText(getGroup(groupPosition).toString());
return parentRow;
}
I also tried removing the LinearLayout wrapper but that didn't fix anything. Can anyone tell me why my xml view isn't working? Thanks.
EDIT: Thanks Flo, new code that is working using the tutorial:
group_row.xml:
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/group_name"
android:paddingLeft="50dp"
android:textSize="30sp"
android:textStyle="normal"
android:layout_height="wrap_content"/>
Main:
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
View parentView = convertView;
if (parentView == null) {
LayoutInflater vi = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
parentView = vi.inflate(R.layout.group_row, null);
}
TextView parentText = (TextView) parentView.findViewById(R.id.group_name);
if (parentText != null) {
parentText.setText(getGroup(groupPosition).toString());
}
return parentText;
}
Your implementation of the getGroupView() method is wrong. At the moment your searching in the activity's layout for a element with the element R.id.row_name which doesn't exist. I guess the line parentRow.setText(getGroup(groupPosition).toString()); throws an exception as parentRow is null.
The correct implementation of the method with a custom row layout from a xml file is to inflate this layout. Check out this tutorial. It's for normal ListViews and adapter but the concept of inflating the row layouts it the same.
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