运行应用程序时缺少选项卡视图

Question

我一直试图运行我创建的应用程序。运行后，它总是给我一个空白页而不是标签视图。下面是我的设计布局和片段中的代码。我在片段中使用tab host。

<RelativeLayout 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"
    tools:context="com.example.redir.wealthtrack.UsageFragment">

    <!-- TODO: Update blank fragment layout -->

    <TabHost
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tabHost"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <TabWidget
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:id="@android:id/tabs"></TabWidget>


            <FrameLayout
                android:id="@android:id/tabcontent"
                android:layout_width="match_parent"
                android:layout_height="match_parent">

                <include
                    android:id="@+id/Tab1"
                    layout="@layout/fragment_tag1"
                    android:layout_width="match_parent"
                    android:layout_height="68dp">
                </include>
                <include
                    android:id="@+id/Tab2"
                    layout="@layout/fragment_tag2"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent">
                </include>
                <include
                    android:id="@+id/Tab3"
                    layout="@layout/fragment_tag3"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent">
                </include>
                <include
                    android:id="@+id/Tab4"
                    layout="@layout/fragment_tag4"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent">
                </include>

            </FrameLayout>
        </LinearLayout>
    </TabHost>

</RelativeLayout>



My fragments used for Tab view


package com.example.redir.wealthtrack;


import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TabHost;

import com.example.redir.wealthtrack.Tabs.Tag1;


/**
 * A simple {@link Fragment} subclass.
 */
public class UsageFragment extends Fragment  {


    public UsageFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_usage, container, false);
        TabHost tab = (TabHost) view.findViewById(R.id.tabHost);
        tab.setup();

        TabHost.TabSpec spec1 = tab.newTabSpec("Tab 1");
        spec1.setIndicator("Tab 1");
        spec1.setContent(R.id.Tab1);
        tab.addTab(spec1);

        TabHost.TabSpec spec2 = tab.newTabSpec("Tab 2");
        spec2.setIndicator("Tab 2");
        spec2.setContent(R.id.Tab2);
        tab.addTab(spec2);

        TabHost.TabSpec spec3 = tab.newTabSpec("Tab 3");
        spec3.setIndicator("Tab 3");
        spec3.setContent(R.id.Tab3);
        tab.addTab(spec3);

        TabHost.TabSpec spec4 = tab.newTabSpec("Tab 4");
        spec4.setIndicator("Tab 4");
        spec4.setContent(R.id.Tab4);
        tab.addTab(spec4);

       return view;



    }
}