java - 使用 ViewPager 后 TabItem 图标消失

Question

我的 TabLayout 很完美，显示有图标，然后我不得不添加一个 ViewPagerOnTabSelectedListener，我的图标不见了。
有谁可以帮助我吗？

我已经尝试过在我的 MainActivity 中添加这个的解决方案，但没有任何改变:

tabLayout.getTabAt(0).setIcon(R.drawable.home);

这是我的代码:

public class MainActivity extends AppCompatActivity {

    private ViewPager pager;
    private BottomNavigationView navigation;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        pager = (ViewPager) findViewById(R.id.pager);
        navigation = (BottomNavigationView) findViewById(R.id.navigation);
        BottomNavigationViewHelper.disableShiftMode(navigation);

        TabLayout tabLayout = new TabLayout(this);
        tabLayout = (TabLayout) findViewById(R.id.toolbar);

        tabLayout.setupWithViewPager(pager);

        tabLayout.addOnTabSelectedListener(
                new TabLayout.ViewPagerOnTabSelectedListener(pager) {
                    @Override
                    public void onTabSelected(TabLayout.Tab tab) {
                        super.onTabSelected(tab);
                        pager.setCurrentItem(tab.getPosition());
                        Log.i("TAG", "onTabSelected: " + tab.getPosition());

                    }
                    @Override
                    public void onTabUnselected(TabLayout.Tab tab) {

                    }

                    @Override
                    public void onTabReselected(TabLayout.Tab tab) {

                    }
                });

        final PagerAdapter mAdapter = new MainPagerAdapter(getSupportFragmentManager());
        pager.setAdapter(mAdapter);

        navigation.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {

            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                switch (item.getItemId()) {
                    case R.id.navigation_adresse:
                        pager.setCurrentItem(0);
                        return true;
                    case R.id.navigation_cognitif:
                        pager.setCurrentItem(1);
                        return true;
                    case R.id.navigation_deplacement:
                        pager.setCurrentItem(2);
                        return true;
                    case R.id.navigation_yeux:
                        pager.setCurrentItem(3);
                        return true;
                }
                return false;
            }

        });
    }

    class MainPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {
            switch (position) {
                case 0:
                    return new MeFragment();
                case 1:
                    return new MeFragment();
                case 2:
                    return new MeFragment();
                case 3:
                default:
                    return new MeFragment();
            }
        }
        @Override
        public int getCount() {
            return 4;
        }
    } 

布局.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="com.blabla.bloublou.MainActivity"
    >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.design.widget.TabLayout
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="top"
            android:background="?attr/colorPrimary">

            <android.support.design.widget.TabItem
                android:id="@+id/home_button"
                android:icon="@drawable/home"
                android:title="home"/>

            <android.support.design.widget.TabItem
                android:id="@+id/me_button"
                android:icon="@drawable/me"
                android:title="moi" />

            <android.support.design.widget.TabItem
                android:id="@+id/configuration_button"
                android:icon="@drawable/tools"
                android:title="configuration"
                />

            <android.support.design.widget.TabItem
                android:id="@+id/help_button"
                android:icon="@drawable/help"
                android:title="aide"/>

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

    <android.support.design.widget.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_gravity="bottom"
        android:background="@color/colorPrimary"
        app:itemIconTint="@color/icon"
        app:itemTextColor="@color/icon"
        app:menu="@menu/navigation">
    </android.support.design.widget.BottomNavigationView>

        <com.umanit.emfsc.NonSwipeableViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_above="@+id/navigation"
            android:layout_below="@+id/toolbar"
            />

        <include layout="@layout/content_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/toolbar"
        android:layout_above="@id/navigation"
        />

    </RelativeLayout>

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

Answer 1

      tabLayout.setupWithViewPager(pager);

            tabLayout.addOnTabSelectedListener(
                    new TabLayout.ViewPagerOnTabSelectedListener(pager) {
                        @Override
                        public void onTabSelected(TabLayout.Tab tab) {
                            super.onTabSelected(tab);
                            pager.setCurrentItem(tab.getPosition());
                            Log.i("TAG", "onTabSelected: " + tab.getPosition());

                        }
                        @Override
                        public void onTabUnselected(TabLayout.Tab tab) {

                        }

                        @Override
                        public void onTabReselected(TabLayout.Tab tab) {

                        }
                    });

            final PagerAdapter mAdapter = new MainPagerAdapter(getSupportFragmentManager());
            pager.setAdapter(mAdapter);
  tabLayout.setupWithViewPager(pager);

进行上述更改，问题是您在寻呼机设置适配器之前设置了 viewpager，如果这不起作用，请告诉我。