Question

我在活动中有一个带有ListView的片段。但是当我运行应用程序时，ListView没有显示，而是只显示一个空白活动。问题是什么？这些是文件：

这是MainActivity.java：

public class MainActivity extends FragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.list_fragment);
    }

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

}

ListFragment.java：

    public class ListFragment extends Fragment{
    ListView list;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
        Bundle savedInstanceState) {

        list = (ListView) inflater.inflate(R.layout.list_fragment, container, false);
        list.setAdapter(new MyAdapter(getActivity()));
        return list;
    }
}

activity_main.xml中：

    <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=".MainActivity" >

    <fragment class="com.dandvrn.ListFragment"
              android:id="@+id/list_fragment"
              android:layout_width="match_parent"
              android:layout_height="match_parent" />


</RelativeLayout>

list_fragment.xml：

    <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ListView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true" >

    </ListView>

</RelativeLayout>

Answer 1

您向xml中的片段提供android:layout_width="0dp"，尝试给出尺寸＆gt; 0

Answer 2

进行以下更改：

1）您必须将活动的内容视图设置为活动的布局，而不是片段的布局：

public class MainActivity extends FragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main); // here
    }

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

}

2）onCreateView应该返回您的片段视图。另外，请执行以下操作以正确访问ListView：

public class ListFragment extends Fragment {
ListView list;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
    Bundle savedInstanceState) {

    View v = inflater.inflate(R.layout.list_fragment, container, false);
    list = (ListView) v.findViewById(R.id.list);
    list.setAdapter(new MyAdapter(getActivity()));
    return v;
}

希望它会对你有所帮助！： - ）

活动中的碎片未显示

2 个答案: