Android ListView 的麻烦

Question

我在尝试运行实现 ListView、用 20 个元素填充并显示它的 Android Activity 时遇到问题: Activity 在启动时崩溃。

以下是相关的 LogCat 错误:

You must supply a resource ID for a TextView
FATAL EXCEPTION: main
java.lang.IllegalStateException: ArrayAdapter requires the resource ID to be a TextView
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:386)
at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
at android.widget.AbsListView.obtainView(AbsListView.java:2177)
at android.widget.ListView.measureHeightOfChildren(ListView.java:1247)
at android.widget.ListView.onMeasure(ListView.java:15848)
at android.widget.RelativeLayout.measureChild(RelativeLayout.java:698)
at android.widget.RelativeLayout.onMeasure(ListView.java:1159)
at android.view.View.measure(View.java:15848)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.app.ActivityThread.main(ActivityThread.java:5013)
Caused by: java.lang.ClassCastException: android.widget.ListView cannot be cast to android.widget.TextView.
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:382)

ThirdActivity.java

package com.example.logger;

import android.os.Bundle;
import android.app.Activity;
import android.app.ListActivity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

public class ThirdActivity extends ListActivity implements OnClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_third);
        final ListView listview = (ListView) findViewById(android.R.id.list);
        String[] values = new String[] {"One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten", 
                "Eleven", "Twelve", "Thirteen", "Fourteen", "Fifteen", "Sixteen", "Seventeen", "Eighteen", "Nineteen",
                "Twenty"};
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.activity_third, android.R.id.list, values);
        setListAdapter(adapter);


    }

        @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.third, menu);
        return true;

        }

        public void attachButton()
        {
            findViewById(R.id.add).setOnClickListener(this);

        }

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

        }
}

结束.java

布局:

Activity_third.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".ThirdActivity" >

   <Button
       android:id="@+id/add"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:layout_alignParentTop="true"
       android:text="@string/add"
       />

   <ListView 
       android:id="@android:id/list"
       android:layout_width="match_parent"
       android:layout_below="@+id/add"
       android:layout_height="wrap_content"

          ></ListView>

</RelativeLayout>

结束.xml

能否根据 LogCat 错误日志告诉我需要更改哪些内容才能使其正常工作？

非常感谢您的帮助。

您真诚的，

毛罗。

Answer 1

ArrayAdapter requires the resource ID to be a TextView

这只是意味着，您必须提供一个带有 TextView 作为参数的布局。适配器会将此 TextView 绑定(bind)到您的数据。但是您当前传递的是包含 ListView 的布局。

所以改变这个:

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.activity_third, android.R.id.list, values);

为此:

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, values);