LinearLayout 中的片段 - Android

Question

我是片段新手，我尝试使用这些片段。 我来自活动的 xml 是：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Loguin"
tools:ignore="MergeRootFrame">

    <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Fragment Test"
    android:id="@+id/btn_FragmentTest"
    android:layout_gravity="center_horizontal"
    android:layout_marginTop="20dp"
    android:layout_marginBottom="0dp" />

    <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"
    android:id="@+id/frgContainer"
    android:layout_marginTop="20dp">

    <fragment
        android:id="@+id/frgLoguin"
        android:layout_marginTop="20dp"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:name="habitatprojects.hubbuildings.Loguin$PlaceholderFragment"
        tools:layout="@layout/fragment_loguin" />

    </LinearLayout>



</LinearLayout>

我想改变LinearLayout里面的片段，我的mainActivity类是：

public class Loguin extends Activity {

private int num = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_loguin);
    if (savedInstanceState == null) {
        getFragmentManager().beginTransaction()
                .add(R.id.container, new PlaceholderFragment())
                .commit();
    }

    Button btnBoton1 = (Button)findViewById(R.id.btn_FragmentTest);

    btnBoton1.setOnClickListener(new View.OnClickListener() {
        public void onClick(View arg0)
        {
            FragmentManager fragmentManager = getFragmentManager();
            FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();

            if(num==0)
            {
                fragmentTransaction.replace(R.id.frgContainer, new PlaceholderFragment())
                        .commit();

                num++;
            }
            else{
                if(num==1)
                {
                    fragmentTransaction.replace(R.id.frgContainer, new PlaceholderFragment2())
                            .commit();

                    num++;
                }
                else{
                    fragmentTransaction.replace(R.id.frgContainer, new PlaceholderFragment3())
                            .commit();

                    num = 0;
                }
            }
        }
    });
 }

我的 PlaceHolderFunction 是：

public static class PlaceholderFragment extends Fragment {

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

public static class PlaceholderFragment2 extends Fragment {

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

public static class PlaceholderFragment3 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_blank2, container, false);
    }
}

为什么我按下按钮不起作用？我做错什么了？对不起我的英语，提前谢谢！

PD：如果您需要更多代码或信息，请告诉我，谢谢！

PD1：当我使用我的设备进行调试时，日志猫只会说我：

11-18 11:33:30.775 6065-6065/habitatprojects.hubbuildings I/ViewRootImpl：ViewRoot 的触摸事件：Touch Down 11-18 11:33:30.835 6065-6065/habitatprojects.hubbuildings I/ViewRootImpl：ViewRoot's 触摸事件：Touch UP

Answer 1

解决了我只需要将我的 LinearLayout 更改为 FrameLayout！谢谢大家！