Viewpager 标签片段和普通片段

Question

我为我糟糕的代码和糟糕的知识提前道歉。我最近才开始使用 Android 和 Java 进行编码

我的问题是我有导航抽屉和标签。虽然如果我从导航抽屉中选择加载到片段中的东西，它不会显示。仅显示选项卡。

我的计划是一个导航抽屉选项卡里面应该有 3 个选项卡，其余的只是没有选项卡的普通页面。

MainActivity.java

http://pastebin.com/TV7aWy9c

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
    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/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <FrameLayout
        android:id="@+id/fragment_layout"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_weight="1"
        android:background="#000000" />

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />

</android.support.v4.widget.DrawerLayout>

app_bar_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="se.themeister.hello.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_height="wrap_content"
        android:layout_width="match_parent"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

        <android.support.design.widget.TabLayout
            android:id="@+id/tab_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/toolbar"
            android:background="?attr/colorPrimary"
            android:elevation="6dp"
            android:minHeight="?attr/actionBarSize"
            android:theme="@style/AppTheme.AppBarOverlay"/>

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="fill_parent"
            android:background="#009900"
            android:layout_below="@id/tab_layout"/>

    </android.support.design.widget.AppBarLayout>

    <include layout="@layout/content_main"/>

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="@dimen/fab_margin"
        android:src="@android:drawable/ic_dialog_email" />

</android.support.design.widget.CoordinatorLayout>

我不知道这是否足够，或者是否需要更多信息或代码

Answer 1

您的代码的问题是您的ViewPager 和TabLayout 应该是Fragment 的一部分，而不是Activity 的一部分。而NavigationDrawer 应该只在视口中（即在容器中）将一个片段替换为另一个片段。现在，在您的代码中，您正尝试以某种方式将新的 Fragment 插入到 ViewPager 中。

Here's 一个非常基本的应用程序，带有导航抽屉，一个带有标签的片段和没有标签的其余片段，您可以将其用作示例：

Activity.xml:

<android.support.v4.widget.DrawerLayout 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/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <android.support.design.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true">

        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:theme="@style/AppTheme.AppBarOverlay">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                android:background="?attr/colorPrimary"
                app:popupTheme="@style/AppTheme.PopupOverlay" />

        </android.support.design.widget.AppBarLayout>

        <FrameLayout
            android:id="@+id/fragmentContainer"
            android:layout_marginTop="?attr/actionBarSize"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>

    </android.support.design.widget.CoordinatorLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />    
</android.support.v4.widget.DrawerLayout>

活动中的代码：

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);

        getSupportFragmentManager().beginTransaction().replace(R.id.fragmentContainer, new FragmentWithTabs()).commit();
    }

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

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.fragment_1) {
            getSupportFragmentManager().beginTransaction().replace(R.id.fragmentContainer, new FragmentWithTabs()).commit();
        } else if (id == R.id.fragment_2) {
            getSupportFragmentManager().beginTransaction().replace(R.id.fragmentContainer, new FragmentWithoutTabs()).commit();
        } else if (id == R.id.fragment_3) {
            getSupportFragmentManager().beginTransaction().replace(R.id.fragmentContainer, new Fragment()).commit();
        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}

也就是说，如您所见，我将 FrameLayout 中的片段替换为 id fragmentContainer。

所有与带有标签的片段相关的逻辑，封装在FragmentWithTabs中：

public class FragmentWithTabs extends Fragment {

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_with_tabs, container, false);
        ViewPager viewPager = (ViewPager)rootView.findViewById(R.id.viewPager);
        TabLayout tabLayout = (TabLayout)rootView.findViewById(R.id.tabLayout);

        viewPager.setAdapter(new FragmentPagerAdapter(getChildFragmentManager()) {
            @Override
            public Fragment getItem(int position) {
                return new SubFragment(position == 0? Color.BLUE : position == 1? Color.WHITE : Color.RED);
            }

            @Override
            public CharSequence getPageTitle(int position) {
                return position+"";
            }

            @Override
            public int getCount() {
                return 3;
            }
        });

        tabLayout.setupWithViewPager(viewPager);
        return rootView;
    }
}

希望对你有帮助