Каков наилучший способ включить эти несколько макетов?

Question

Я следовал этому руководству: https://github.com/codepath/android_guides/wiki/Fragment-Navigation-Drawer

Я добавил свой собственный XML-файл с include, который представляет среднюю часть основного действия, где находится панель навигации.Теперь я нажимаю на ящик, а затем на один предмет.После этого название панели инструментов меняется, и я думаю, что фрагмент визуализируется, но я не вижу его, потому что средняя часть моей основной деятельности все еще находится впереди: / Если я удаляю среднюю часть include, я вижу фрагменты.

Я попытался создать новый XML-файл с новым дизайном для средней части, он показывает ту же проблему, что означает, что проблема не в средней части XML.

Вот мой XMLза мою деятельность:

<!-- This DrawerLayout has two children at the root  -->
<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <!-- This LinearLayout represents the contents of the screen  -->
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <!-- The ActionBar displayed at the top -->
        <include
            layout="@layout/toolbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

        <include layout="@layout/chooser_middle_end_part"/> **MID PART**

        <!-- The main content view where fragments are loaded -->
        <FrameLayout
            android:id="@+id/flContent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
    </LinearLayout>

    <!-- The navigation drawer that comes from the left -->
    <!-- Note that `android:layout_gravity` needs to be set to 'start' -->
    <android.support.design.widget.NavigationView
        android:id="@+id/nvView"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:background="@android:color/white"
        app:menu="@menu/drawer_menu"
        app:headerLayout="@layout/header"/>
</android.support.v4.widget.DrawerLayout>

Вот моя деятельность:

import android.content.res.Configuration;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;

public class ChoosingActivity extends AppCompatActivity {

    private DrawerLayout mDrawer;
    private Toolbar toolbar;
    private NavigationView nvDrawer;

    // Make sure to be using android.support.v7.app.ActionBarDrawerToggle version.
    // The android.support.v4.app.ActionBarDrawerToggle has been deprecated.
    private ActionBarDrawerToggle drawerToggle;


    public void userChoosed(View view) {


        Intent choosedIntent = new Intent(getApplicationContext(), MainActivity.class);
        startActivity(choosedIntent);

    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_choosing);

        // Set a Toolbar to replace the ActionBar.
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        // Find our drawer view
        mDrawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawerToggle = setupDrawerToggle();

        // ...From section above...
        // Find our drawer view
        nvDrawer = (NavigationView) findViewById(R.id.nvView);
        // Setup drawer view
        setupDrawerContent(nvDrawer);

        // Tie DrawerLayout events to the ActionBarToggle
        mDrawer.addDrawerListener(drawerToggle);
    }

    private ActionBarDrawerToggle setupDrawerToggle() {
        // NOTE: Make sure you pass in a valid toolbar reference.  ActionBarDrawToggle() does not require it
        // and will not render the hamburger icon without it.
        return new ActionBarDrawerToggle(this, mDrawer, toolbar, R.string.drawer_open,  R.string.drawer_close);
    }

    /*@Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // The action bar home/up action should open or close the drawer.
        switch (item.getItemId()) {
            case android.R.id.home:
                mDrawer.openDrawer(GravityCompat.START);
                return true;
        }

        return super.onOptionsItemSelected(item);

    }*/

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (drawerToggle.onOptionsItemSelected(item)) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    // `onPostCreate` called when activity start-up is complete after `onStart()`
    // NOTE 1: Make sure to override the method with only a single `Bundle` argument
    // Note 2: Make sure you implement the correct `onPostCreate(Bundle savedInstanceState)` method.
    // There are 2 signatures and only `onPostCreate(Bundle state)` shows the hamburger icon.
    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        // Sync the toggle state after onRestoreInstanceState has occurred.
        drawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        // Pass any configuration change to the drawer toggles
        drawerToggle.onConfigurationChanged(newConfig);
    }

    private void setupDrawerContent(NavigationView navigationView) {
        navigationView.setNavigationItemSelectedListener(
                new NavigationView.OnNavigationItemSelectedListener() {
                    @Override
                    public boolean onNavigationItemSelected(MenuItem menuItem) {
                        selectDrawerItem(menuItem);
                        return true;
                    }
                });
    }

    public void selectDrawerItem(MenuItem menuItem) {
        // Create a new fragment and specify the fragment to show based on nav item clicked
        Fragment fragment = null;
        Class fragmentClass;
        switch (menuItem.getItemId()) {
            case R.id.nav_meetings:
                fragmentClass = AusstehendeTreffenFragment.class;
                break;
            case R.id.nav_finished_meetings:
                fragmentClass = AbgeschlosseneTreffenFragment.class;
                break;
            case R.id.nav_rate:
                fragmentClass = TreffenBewertenFragment.class;
                break;
            case R.id.nav_edit_profile:
                fragmentClass = ProfilBearbeitenFragment.class;
                break;
            case R.id.nav_settings:
                fragmentClass = AllgemeineEinstellungenFragment.class;
                break;
            default:
                fragmentClass = AusstehendeTreffenFragment.class;
        }

        try {
            fragment = (Fragment) fragmentClass.newInstance();
        } catch (Exception e) {
            e.printStackTrace();
        }

        // Insert the fragment by replacing any existing fragment
        FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();

        // Highlight the selected item has been done by NavigationView
        menuItem.setChecked(true);
        // Set action bar title
        setTitle(menuItem.getTitle());
        // Close the navigation drawer
        mDrawer.closeDrawers();
    }

    public void onBackPressed() {
        DrawerLayout layout = (DrawerLayout)findViewById(R.id.drawer_layout);
        if (layout.isDrawerOpen(GravityCompat.START)) {
            layout.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }
}

Моя средняя часть xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/ll"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/new_gradients"
    android:gravity="center"
    android:orientation="vertical"
    android:padding="10dp">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:clipToPadding="false"
        android:gravity="center"
        android:orientation="horizontal">

        <android.support.v7.widget.CardView
            android:id="@+id/bankcardId"
            android:layout_width="160dp"
            android:layout_height="190dp"
            android:layout_margin="10dp"
            android:clickable="true"
            android:foreground="?android:attr/selectableItemBackground">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:background="@color/colorPrimary"
                android:gravity="center"
                android:orientation="vertical">

                <ImageView
                    android:layout_width="64dp"
                    android:layout_height="64dp"
                    android:background="@drawable/cerclebackgroundturcis"
                    android:padding="10dp" />

                <TextView
                    //...//

                <View
                    //...//

                <TextView
                   //...//

            </LinearLayout>
        </android.support.v7.widget.CardView>

Пожалуйста, помогите мне, спасибо:)