18

MyFragment.java

public class MyFragment extends Fragment {
    private onItemSelectedListener listener;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment, container,
                false);
        btn_myButton = (Button) view.findViewById(R.id.btn_new_client);
        btn_myButton .setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                updateDetail("New Layout");
            }
        });
        return view;
    }

    Button btn_myButton;

    public interface onItemSelectedListener {
        public void onItemSelected(String link);
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        if (activity instanceof onItemSelectedListener) {
            listener = (onItemSelectedListener) activity;
        } else {
            throw new ClassCastException(activity.toString()
                    + " must implemenet OnItemSelectedListener");
        }
    }
    public void updateDetail(String s) {
        listener.onItemSelected(s);
    }
}

MainActivity.java

public class MainActivity extends Activity implements
    onItemSelectedListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.main_activity);
    super.onCreate(savedInstanceState);
}

public void onItemSelected(String link) {
    FragmentManager manager = getFragmentManager();
    FragmentTransaction transaction = manager.beginTransaction();
    Fragment fragment;
    if ("New Layout".equals(link)) {
        fragment = new Fragment1();
        transaction.replace(R.id.detailFragment, fragment);
        transaction.commit();
    }
}
}

片段1.java

public class Fragment1 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.newfragmentt, container,
                false);
        return v;
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
    }
}

片段.xml

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

    <Button
        android:id="@+id/btn_new_client"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:ems="8"
        android:gravity="center|center_vertical"
        android:padding="2dp"
        android:text="@string/new_client"
        android:textColor="#FFFFFF" >
    </Button>

</LinearLayout>

main_activity.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#4B6C9E"
    android:baselineAligned="false"
    android:orientation="horizontal" >

    <fragment        
        android:id="@+id/FragmentId"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"
        class="com.examples.MyProject.MyFragment" >
    </fragment>
    <FrameLayout
        android:id="@+id/detailFragment"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="2" >
    </FrameLayout>

</LinearLayout>

LogCat 错误：

 FATAL EXCEPTION: main
 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.elintsys.iCaseDiary/com.examples.MyProject.MainActivity}: android.view.InflateException: Binary XML file line #8: Error inflating class fragment
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
    at android.app.ActivityThread.access$600(ActivityThread.java:123)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:137)
    at android.app.ActivityThread.main(ActivityThread.java:4424)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:511)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
    at dalvik.system.NativeStart.main(Native Method)
 Caused by: android.view.InflateException: Binary XML file line #8: Error inflating class fragment
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:697)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
    at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:251)
    at android.app.Activity.setContentView(Activity.java:1862)
    at com.examples.MyProject.MainActivity.onCreate(CaseEntryActivity.java:15)
    at android.app.Activity.performCreate(Activity.java:4492)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
    ... 11 more
 Caused by: java.lang.IllegalStateException: Fragment com.elintsys.iCaseDiary.CaseEntryFragment did not create a view.
    at android.app.Activity.onCreateView(Activity.java:4293)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:673)
    ... 21 more
 Sending signal. PID: 16275 SIG: 9

请朋友们帮帮我。

4

4 回答 4

17

你需要扭转这个：

setContentView(R.layout.main_activity); 
super.onCreate(savedInstanceState).

进入这个：

super.onCreate(savedInstanceState). 
setContentView(R.layout.main_activity);

在您的活动中onCreate。

于 2013-08-19T06:33:38.607 回答
3

即使我在 super.onCreate 之后调用 setContentView，我也遇到了这个错误。在我的情况下，我在我的超类的 onCreate 方法中设置了一个工作片段，该方法在 setContentView 之前被调用并触发了此处记录的错误：

https://code.google.com/p/android/issues/detail?id=22564

为了解决这个问题，我不得不将工作片段的初始化移到活动生命周期稍后调用的单独方法中。

根据要求，该代码如下所示：

public class BaseActivity extends ActionBarActivity {

    private static final String TAG_TASK_FRAGMENT = "task_fragment";

    protected TaskFragment taskFragment; // Used to hold a reference to the active activity between config changes

    protected void setupTaskFragment() {
        // It would be great if we could just do this in onCreate, but setting up the task fragment
        // before calling setContentView() triggers the bug described here:
        //
        // https://code.google.com/p/android/issues/detail?id=22564
        //
        // So we just need to make sure Activities that run async tasks call this setup function
        // before they do.

        FragmentManager fm = getSupportFragmentManager();
        taskFragment = (TaskFragment) fm.findFragmentByTag(TAG_TASK_FRAGMENT);

        // If the Fragment is non-null, then it is currently being
        // retained across a configuration change.
        if (taskFragment == null) {
            taskFragment = new TaskFragment();
            fm.beginTransaction().add(taskFragment, TAG_TASK_FRAGMENT).commit();
            fm.executePendingTransactions();
        }

    }

}

public class ChildActivity extends BaseActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);  // If this call adds a fragment, you will have problems
        setContentView(R.layout.activity_child);
        setupTaskFragment(); // So we have to add our task fragment here, after we've called setContentView()

        // further initialization here
    }

}

/**
 *
 *  TaskFragment
 *
 * We use this fragment to manage async tasks between configuration changes.  The fragment calls
 * setRetainInstance(true) in its constructor, which makes it so that it will not be recreated
 * between configuration events (like screen rotation).  Async tasks running from the fragment 
 * can then be kept up to date on which activity they belong to.
 */

public class TaskFragment extends Fragment {

    private ArrayList<AsyncTask> asyncTasks = new ArrayList<AsyncTask>();

    public TaskFragment() {
        super();
        setRetainInstance(true);
    }

    public void addTask(AsyncTask task) {
        asyncTasks.add(task);
    }

    public void removeTask(AsyncTask task) {
        asyncTasks.remove(task);
    }

    public Application getApplication() {
        Activity activity = getActivity();
        if (activity != null)
            return activity.getApplication();
        else
            return null;
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        for (AsyncTask task : asyncTasks) {
            task.onAttach(activity);
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        for (AsyncTask task : asyncTasks) {
            task.onDetach();
        }
    }
}
于 2015-04-03T21:01:17.123 回答
1

我有同样的问题，但已经有setContentViewand super.onCreate。在我的片段活动中添加以下内容解决了这个问题：

@Override
public void onActivityCreated(Bundle savedInstanceState) {
   super.onActivityCreated(savedInstanceState);
}

在进一步进入我的项目后，这个问题仍然存在，第二个修复正在替换：

    <fragment
    android:id="@+id/output"
    class=".Fragment_1"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

和：

    <FrameLayout
    android:id="@+id/fragment_frame_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <fragment
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:name=".Fragment_1"
        android:id="@+id/fragment"
        tools:layout="@layout/fragment_two" />
    </FrameLayout>

显然，“您无法替换静态放置在 xml 布局文件中的片段”，如以下问题的答案所示：Android - fragment .replace() doesn't replace content - puts it on top

于 2018-08-24T02:19:42.750 回答
1

除了 Mel Stanley 所说的之外，您还需要确保将 android:tag 添加到加载片段的 xml 活动中：

<fragment
android:id="@+id/fragment_container"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:name="com.your_app.name.fragments.NameOfFragment"
android:tag="fragment_tag"
tools:layout="@layout/layout_fragment" 
/>

这确保了当第一次使用 xml 加载片段时，它不会使用 Mel 的代码重新加载。如果您忽略了这一点，您将在第一次运行时加载 2 次片段 - 如果您有异步请求在完成时更改布局，这将是一个问题。

于 2017-11-15T20:15:40.287 回答