嗨，我有一个可扩展列表，当我试图用这段代码将它连接到一个XML文件时，出现了一个错误。
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.directions);
// Set up our adapter
mAdapter = new MyExpandableListAdapter();
setListAdapter(mAdapter);
registerForContextMenu(getExpandableListView());
}
使用这个代码，当我重定向到整个Java文件的按钮时，得到一个力。（查看下面的完整代码）
木猫说：
10-25 17:37:39.512:错误/AndroidRuntime（547）：
java.lang.RuntimeException:无法启动活动
组件信息{com.sammy.umass/com.sammy.umass.directionScreenActivity}：
java.lang.RuntimeException:内容必须具有
id属性为“android.r.id.list”的expandableListView
我只需要删除标题栏，添加一个背景图像和美化它基本上。
完整代码：
package com.sammy.umass;
import android.app.ExpandableListActivity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.Gravity;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.ContextMenu.ContextMenuInfo;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ExpandableListView.ExpandableListContextMenuInfo;
public class DirectionsScreenActivity extends ExpandableListActivity {
ExpandableListAdapter mAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.directions);
// Set up our adapter
mAdapter = new MyExpandableListAdapter();
setListAdapter(mAdapter);
registerForContextMenu(getExpandableListView());
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
//menu.setHeaderTitle("Sample menu");
//menu.add(0, 0, 0, R.string.expandable_list_sample_action);
}
@Override
public boolean onContextItemSelected(MenuItem item) {
ExpandableListContextMenuInfo info = (ExpandableListContextMenuInfo) item.getMenuInfo();
String title = ((TextView) info.targetView).getText().toString();
int type = ExpandableListView.getPackedPositionType(info.packedPosition);
if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) {
int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition);
int childPos = ExpandableListView.getPackedPositionChild(info.packedPosition);
Toast.makeText(this, title + ": Child " + childPos + " clicked in group " + groupPos,
Toast.LENGTH_SHORT).show();
return true;
} else if (type == ExpandableListView.PACKED_POSITION_TYPE_GROUP) {
int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition);
Toast.makeText(this, title + ": Group " + groupPos + " clicked", Toast.LENGTH_SHORT).show();
return true;
}
return false;
}
/**
* A simple adapter which maintains an ArrayList of photo resource Ids.
* Each photo is displayed as an image. This adapter supports clearing the
* list of photos and adding a new photo.
*
*/
public class MyExpandableListAdapter extends BaseExpandableListAdapter {
// Sample data set. children[i] contains the children (String[]) for groups[i].
private String[] groups = { " Academic Buildings", " Residential Buildings", " Dining Commons", " All Buildings A-Z" };
private String[][] children = {
//Academic Buildings
{ "Agricultural Engineering Bldg", "Army ROTC Bldg", "Arnold House", "(Studio) Arts Building" },
//Residence Halls
{ "Baker Hall", "Brett Hall", "Brooks Hall", "Brown Hall","Butterfield Hall","Cance Hall","Cashin Hall","Chadboourne Hall",
"Coolidge Hall","Crabtree Hall","Crampton Hall","Dickinson Hall","Dwight Hall","Emerson Hall","Field Hall",
"Gorman Hall","Grayson Hall","Greenough Hall","Hamlin Hall","James Hall","John Adams Hall","John Quincy Adams Hall",
"Johnson Hall","Kennedy Hall","Knowlton Hall","Leach Hall","Lewis Hall","Lincoln Apts","Mackimmie Hall","Mary Lyon Hall",
"McNamara Hall","Melville Hall","Moore Hall","North Residence A","North Residence B","North Residence C","North Residence D",
"North Village Apts","Patterson Hall","Pierpont Hall","Prince Hall","Thatcher Hall","Thoreau Hall","Van Meter Hall",
"Washington Hall","Webster Hall","Wheeler Hall"},
//Dining Commons
{ "Berkshire", "Franklin","Hampden","Hampshire","Worcester" },
{ "Agricultural Engineering Bldg", "Army ROTC Bldg", "Arnold House", "(Studio) Arts Building" }
};
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(DirectionsScreenActivity.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(final int groupPosition,final int childPosition, boolean isLastChild,
View convertView, ViewGroup parent) {
TextView textView = getGenericView();
textView.setText(getChild(groupPosition, childPosition).toString());
textView.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
Uri uriToOpen = getUriForView(groupPosition, childPosition);
Intent i = new Intent(Intent.ACTION_VIEW, uriToOpen);
startActivity(i);
}
private Uri getUriForView(int groupPosition, int childPosition)
{
//Academic Builds
//Residence Halls
if(groupPosition == 1 && childPosition == 0)
return Uri.parse("google.navigation:q=160+Clark+Hill+Road+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 1)
return Uri.parse("google.navigation:q=151+Infirmary+Way+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 2)
return Uri.parse("google.navigation:q=160+Infirmary+Way+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 3)
return Uri.parse("google.navigation:q=92+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 4)
return Uri.parse("google.navigation:q=171+Infirmary+Way+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 5)
return Uri.parse("google.navigation:q=191+Fearing+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 6)
return Uri.parse("google.navigation:q=112+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 7)
return Uri.parse("google.navigation:q=110+Orchard+Hill+Drive+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 8)
return Uri.parse("google.navigation:q=630+Massachusetts+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 9)
return Uri.parse("google.navigation:q=17+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 10)
return Uri.parse("google.navigation:q=256+Sunset+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 11)
return Uri.parse("google.navigation:q=151+Orchard+Hill+Drive+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 12)
return Uri.parse("google.navigation:q=41+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 13)
return Uri.parse("google.navigation:q=151+Southwest+Circle+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 14)
return Uri.parse("google.navigation:q=171+Orchard+Hill+Drive+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 15)
return Uri.parse("google.navigation:q=90+Butterfield+Terrace+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 16)
return Uri.parse("google.navigation:q=161+Orchard+Hill+Drive+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 17)
return Uri.parse("google.navigation:q=120+Orchard+Hill+Drive+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 18)
return Uri.parse("google.navigation:q=739+North+Pleasant+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 19)
return Uri.parse("google.navigation:q=660+Massachusetts+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 20)
return Uri.parse("google.navigation:q=161+Fearing+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 21)
return Uri.parse("google.navigation:q=171+Fearing+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 22)
return Uri.parse("google.navigation:q=380+Thatcher+Road+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 23)
return Uri.parse("google.navigation:q=42.38421349589919+-72.52963542938232"+"&mode=w");
if(groupPosition == 1 && childPosition == 24)
return Uri.parse("google.navigation:q=691+North+Pleasant+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 25)
return Uri.parse("google.navigation:q=21+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 26)
return Uri.parse("google.navigation:q=340+Thatcher+Road+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 27)
return Uri.parse("google.navigation:q=341+Lincoln+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 28)
return Uri.parse("google.navigation:q=230+Sunset+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 29)
return Uri.parse("google.navigation:q=43+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 30)
return Uri.parse("google.navigation:q=102+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 31)
return Uri.parse("google.navigation:q=650+Massachusetts+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 32)
return Uri.parse("google.navigation:q=111+Southwest+Circle+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 33)
return Uri.parse("google.navigation:q=56+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 34)
return Uri.parse("google.navigation:q=58+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 35)
return Uri.parse("google.navigation:q=54+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 36)
return Uri.parse("google.navigation:q=52+Eastman+Lane+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 37)
return Uri.parse("google.navigation:q=990+North+Pleasant+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 38)
return Uri.parse("google.navigation:q=204+Sunset+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 39)
return Uri.parse("google.navigation:q=201+Fearing+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 40)
return Uri.parse("google.navigation:q=286+Sunset+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 41)
return Uri.parse("google.navigation:q=300+Thatcher+Road+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 42)
return Uri.parse("google.navigation:q=640+Massachusetts+Avenue+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 43)
return Uri.parse("google.navigation:q=180+Clark+Hil+Road+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 44)
return Uri.parse("google.navigation:q=181+Fearing+Street+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 45)
return Uri.parse("google.navigation:q=141+Orchard+Hill+Drive+Amherst+MA+01003"+"&mode=w");
if(groupPosition == 1 && childPosition == 46)
return Uri.parse("google.navigation:q=171+Infirmary+Way+Amherst+MA+01003"+"&mode=w");
//Dining Commons
//All Buildings
return null;
}
});
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 isChildSelectable(int groupPosition, int childPosition) {
return true;
}
public boolean hasStableIds() {
return true;
}
}
}
XML代码
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
</LinearLayout>
最佳答案
使用expandablelistadapter时，提供的xml布局需要在其中包含一个expandablelistview元素，id属性设置为android.r.id.list。问题出在directions.xml布局上。确保在directions.xml中有一个expandableListView元素，并且它的id属性设置为andoird.r.id.list。您需要在directions.xml中执行此操作：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ExpandableListView
android:id="@android:id/list"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</ExpandableListView>
</LinearLayout>