Android 如何使用可扩展列表的xml布局？

您好，我有这个可扩展列表，当我试图使用此代码将它连接到xml文件时，我遇到了一个错误

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.directions);
    // Set up our adapter
    mAdapter = new MyExpandableListAdapter();
    setListAdapter(mAdapter);
    registerForContextMenu(getExpandableListView());
}

使用这段代码，当我单击重定向到整个java文件的按钮时，会得到一个强制关闭。（查看下面的完整代码） 日志猫说：

10-25 17:37:39.512：错误/AndroidRuntime（547）： java.lang.RuntimeException:无法启动活动 ComponentInfo{com.sammy.umass/com.sammy.umass.DirectionsScreenActivity}： java.lang.RuntimeException：您的内容必须具有 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，并基本上美化它

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>

---

使用ExpandableListAdapter时，提供的XML布局中需要有一个id属性设置为android.R.id.list的ExpandableListView元素。您的问题在directions.xml布局中。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directoions.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>

---

您必须在xml文件中为ExpandableListView添加android内置id，如下所示，并删除您自己使用

android:id=“@+id/anyname”声明的id

为规范目的而编辑。使用@LalitPoptani发布的代码，并给他一张信用卡的升级票。我应该把这个代码放在哪里？android:background=“@color/white”在线性布局或expandablelistview中？这是一个单独的问题，所以请在一个新问题中提问。也就是说，为什么不自己做实验和尝试呢？经验是最好的老师：）我总是觉得尝试不同的东西很有趣，看看什么有用，什么不有用。哈哈，我做了实验！我会继续努力，如果我不明白，我会问另一个问题。再次感谢@squid267这才是真正的开发者/黑客的精神！恭喜！

       <ExpandableListView 
        android:id="@android:id/list"
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content">
        </ExpandableListView>