嵌套的操作栏选项卡(带有ViewPager) [英] Nested Action Bar Tabs(with ViewPager)

问题描述

我有一个使用操作栏"选项卡(带有ViewPager)的项目. 在选项卡之间滑动时，选项卡的移动非常平稳，但是我需要在TAB 2中添加两个子选项卡，然后再移至下一个选项卡，或者当然也要移回下一个选项卡，就像在Glassdoor或Flipboard上一样.

I have a project that uses Action Bar Tabs(with ViewPager). Tabs move really smoothly when swiping between them, but I need to add two sub tabs, in TAB 2, then move to the next tabs or of course back, just like on the Glassdoor or Flipboard.

请帮助.

MainActivity

MainActivity

public class MainActivity extends AppCompatActivity {


private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;

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

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
    mViewPager = (ViewPager) findViewById(R.id.container);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
    tabLayout.setupWithViewPager(mViewPager);

}


public class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {

            switch (position) {
                case 0:
                    return Tab1Fragment.newInstance();
                case 1:
                    return Tab2Fragment.newInstance();
                default:
                    return Tab3Fragment.newInstance();
            }
    }

    @Override
    public int getCount() {
        // Show 3 total pages.
        return 3;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        switch (position) {
            case 0:
                return "Tab 1";
            case 1:
                return "Tab 2";
            case 2:
                return "Tab 3";
        }
        return null;
    }
}
}

activity_main.xml

activity_main.xml

<android.support.design.widget.AppBarLayout
    android:id="@+id/appbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:paddingTop="@dimen/appbar_padding_top"
    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:layout_scrollFlags="scroll|enterAlways"
        app:popupTheme="@style/AppTheme.PopupOverlay">

    </android.support.v7.widget.Toolbar>

    <android.support.design.widget.TabLayout
        android:id="@+id/tabs"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

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

<android.support.v4.view.ViewPager
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior" />

Tab2Fragment-我想在其中嵌套SubTab1Fragment和SubTab2Fragment

Tab2Fragment- where i want to nest SubTab1Fragment and SubTab2Fragment

public class Tab2Fragment extends Fragment {   
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";


public Tab2Fragment() {
    // Required empty public constructor
}


// TODO: Rename and change types and number of parameters
public static Tab2Fragment newInstance() {
    Tab2Fragment fragment = new Tab2Fragment();

    return fragment;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {

    }
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_tab2, container, false);
}

}

fragment_tab2.xml

fragment_tab2.xml

<FrameLayout 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.r3dm4n.testprojectapp.Tab2Fragment">

<!-- TODO: Update blank fragment layout -->
<TextView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="@string/hello_blank_fragment" />

推荐答案

我知道了. 我还在 Github 上发布了一个演示项目.

I figured this out. I've also posted a demo project on Github

在MainActivity中，您需要为想要嵌套"的片段返回一个新的片段，如下所示:

In the MainActivity you need to return a new Fragment for the one you want "nested" like this:

@Override
    public Fragment getItem(int position) {

        switch (position) {
            case 0:
                return Tab1Fragment.newInstance();
            case 1:
                return new Tab2Fragment();
            default:
                return Tab3Fragment.newInstance();
        }

在TAB2片段中，您希望其他嵌套片段进行以下更改:

In TAB2 fragment, where you want the other nested fragments make the following changes:

public class Tab2Fragment extends Fragment {

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {


    View view = inflater.inflate(R.layout.fragment_tab2, container, false);
    ViewPager mViewPager = (ViewPager) view.findViewById(R.id.container_main);
    SectionsPagerAdapter mSectionsPagerAdapter = new SectionsPagerAdapter(getChildFragmentManager());
    mViewPager.setAdapter(mSectionsPagerAdapter);

    return view;

}


private class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        switch (position) {
            case 0:
                return Nest1Fragment.newInstance(1);
            default:
                return Nest2Fragment.newInstance(2);
        }

    }

    @Override
    public int getCount() {
        // Show 4 total pages.
        return 2;
    }

    @Override
    public CharSequence getPageTitle(int position) {

        switch (position) {
            case 0:
                return "Nested 1";
            default:
                return "Nested 2";
        }


    }
}


}

fragment_tab2.xml

fragment_tab2.xml

<android.support.v4.view.ViewPager
    android:id="@+id/container_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    app:layout_scrollFlags="scroll|enterAlways">

    <android.support.design.widget.TabLayout
        android:id="@+id/tabs2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/colorPrimary" />
    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:layout_scrollFlags="scroll|enterAlways"
        app:popupTheme="@style/AppTheme.PopupOverlay">
    </android.support.v7.widget.Toolbar>
</android.support.v4.view.ViewPager>

这篇关于嵌套的操作栏选项卡(带有ViewPager)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！