Question

在我向程序中添加一些新代码之前它运行正常。我想添加一个listView来显示一些消息，但它不起作用。当应用程序进入此活动时，程序崩溃... 我补充说：

    String[] studentList = {"zhangsan","lisi"};
    ListView stdListView = (ListView)findViewById(R.id.studentListView);
    ArrayAdapter<String> arrayAdapter;
    arrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_2,studentList);
    stdListView.setAdapter(arrayAdapter);
    stdListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            String result = parent.getItemAtPosition(position).toString();
            AlertDialog.Builder choice = new AlertDialog.Builder(EditActivity.this);
            choice.setTitle(result);
        }
    });

为：

    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_edit);

    String[] studentList = {"zhangsan","lisi"};
    ListView stdListView = (ListView)findViewById(R.id.studentListView);
    ArrayAdapter<String> arrayAdapter;
    arrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_2,studentList);
    stdListView.setAdapter(arrayAdapter);
    stdListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            String result = parent.getItemAtPosition(position).toString();
            AlertDialog.Builder choice = new AlertDialog.Builder(EditActivity.this);
            choice.setTitle(result);
        }
    });

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });

    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
            this, drawer, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
    drawer.setDrawerListener(toggle);
    toggle.syncState();

    NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
    navigationView.setNavigationItemSelectedListener(this);
}

以下是布局的xml文件。我补充道：

    <ListView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/studentListView"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true" />

为：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
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"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="n402lab.door.EditActivity"
tools:showIn="@layout/app_bar_edit">

<ListView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/studentListView"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true" />
</RelativeLayout>

Answer 1

在我看到关于这个问题的评论之后，我试着自己调试它。在此之前，我还不知道如何调试应用程序。我看到＆＃34;您必须为TextView提供资源ID＆＃34; 我搜索解决方案，最后我替换了＃34; android.R.layout.simple_list_item_2＆＃34; by＆＃34; android.R.layout.simple_list_item_1＆＃34; 它的确有效。非常感谢！

为什么我的Android应用程序在添加listView后崩溃了？

1 个答案: