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();
    }
}
}

Fragment1.java

public class Fragment1 extends Fragment {

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

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

fragment.xml之

<?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

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