将元素添加到fragment_main.xml不提 [英] Adding elements to fragment_main.xml does noting

问题描述

我添加的EditText和Button标签的fragments_main.xml。
不过，这并不显示一个文本字段和按钮，当我运行应用程序。
然而，当我加入的EditText和按钮activity_main.xml中然后正常工作。请帮忙。我有ADT v22.2.1-833290
这里是activity_main.xml中：

I added EditText and Button tags to the fragments_main.xml. But it doesn't show a text field and button when i run the application. However when i add the EditText and Button to activity_main.xml then it works fine. Please help. I have ADT v22.2.1-833290 Here is the activity_main.xml :

<LinearLayout 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" >
</LinearLayout>

下面是fragment_main.xml：

Here is the fragment_main.xml :

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="horizontal" >

<EditText android:layout_weight="1"
    android:id="@+id/edit_message"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:hint="@string/edit_message" />
 <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/button_send" />

</LinearLayout>

这是在MainActivity code：

And here is the MainActivity Code :

public class MainActivity extends Activity {

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

@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, menu);
    return true;
}

}

推荐答案

你在哪里加载fragment_main.xml在code？

Where do you load the fragment_main.xml in your code?

通常情况下，活动应该加载一个片段和片段应加载您刚才提到的XML文件。

Typically, an Activity should load a Fragment and the Fragment should load the xml file that you just mentioned.

在上面的code，你只加载 activity_main.xml中文件中的 MainActivity 。因此，只有 activity_main.xml中显示在视图中的内容。

In the above code, you are only loading the activity_main.xml file in the MainActivity. Therefore, only the content of activity_main.xml is displayed in the view.

更新

要加载 fragment_main XML文件，您可以：

To load the fragment_main XML file, you can either:

• 从的setContentView替换code在 MainActivity 行（R.layout.activity_main）; 到的setContentView（R.layout.fragment_main）;

• Replace the line of code in MainActivity from setContentView(R.layout.activity_main); to setContentView(R.layout.fragment_main);

或者，创建在延长片段 A类 MainActivity ，让该类加载 fragment_main XML。

OR, create a class extending Fragment in the MainActivity and let that class load the fragment_main XML.

要做到后者，你可以按照一步一步的指导在这里：片段|添加UI

To do the latter, you can follow the step by step guide here: Fragments | Adding a UI

在本质上，创建一个类：

In essence, Create a class:

public static class ExampleFragment extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_main, container, false);
    }
}

和加载创建片段在 MainActivity （片段|添加片段的活动）。

要加载，你可以声明 activity_main.xml中布局内片段

To load, you can either declare the fragment inside the activity_main.xml layout

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <fragment android:name="com.example.ui.ExampleFragment"
            android:id="@+id/example_fragment"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
</LinearLayout>

或者试试穆斯塔法给出了答案。

Or try the answer mustafa gave.

我希望这有助于。

这篇关于将元素添加到fragment_main.xml不提的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！