如何在 Android 中在另一个活动中显示一个活动？

How to display one activity inside another in Android?

提问by AMH

I have one activity and want to display another inside it. Here's my layout:

我有一项活动，想在其中显示另一项活动。这是我的布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">

  <LinearLayout
      android:orientation="horizontal"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"
      android:layout_weight="1">
  </LinearLayout>

</LinearLayout>

How can I display an Activityin inner LinearLayouton button click?

如何在按钮单击时显示Activity内部LinearLayout？

回答by Andrey Ermakov

Use one layout for several activities

为多项活动使用一种布局

Layout instance is inflated for each activity using a setContentViewmethod, usually in onCreate:

布局实例使用一种setContentView方法为每个活动膨胀，通常在onCreate：

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

So there's no problem to use the same XMLlayout for different activities.

所以XML对于不同的活动使用相同的布局是没有问题的。

Display one activity inside another

在另一个活动中显示一个活动

You can use a FragmentAPI to complete the task. See full details in developer's guide.

您可以使用FragmentAPI 来完成任务。请参阅开发人员指南中的完整详细信息。

• Declare a layout like that and Android will create fragments for you:

  <?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">
  
      <fragment android:name="com.example.MyFragment"
              android:id="@+id/my_fragment"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:layout_weight="1" />
  
  </LinearLayout>
  

  Then create a MyFragmentclass and load it when appropriate.

• Create fragments yourself. Do not define the Fragmentin XMLlayout:

  <?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"
      android:id="@+id/my_parent_layout">
  
  </LinearLayout>
  

  After your parent Activityis created you can add a new Fragmentin this way:

  FragmentManager fragmentManager = getFragmentManager()
  FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
  MyFragment fragment = new MyFragment();
  fragmentTransaction.add(R.id.my_parent_layout, fragment);
  fragmentTransaction.commit();
  

  Here MyFragmentis defined like this:

  public class MyFragment extends Fragment {
      ...
  }
  

• 声明一个这样的布局，Android 会为你创建片段：

  <?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">
  
      <fragment android:name="com.example.MyFragment"
              android:id="@+id/my_fragment"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:layout_weight="1" />
  
  </LinearLayout>
  

  然后创建一个MyFragment类并在适当的时候加载它。

• 自己创建片段。不要定义FragmentinXML布局：

  <?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"
      android:id="@+id/my_parent_layout">
  
  </LinearLayout>
  

  Activity创建父项后，您可以通过Fragment以下方式添加新项：

  FragmentManager fragmentManager = getFragmentManager()
  FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
  MyFragment fragment = new MyFragment();
  fragmentTransaction.add(R.id.my_parent_layout, fragment);
  fragmentTransaction.commit();
  

  这里MyFragment是这样定义的：

  public class MyFragment extends Fragment {
      ...
  }
  

If you're targeting below Android 3.0, consider using support packagefor that.

如果您的目标是低于 Android 3.0，请考虑为此使用支持包。