Question

我在一个应用程序栏内有三个选项卡布局。当我更改当前标签时，我也想更改应用栏的背景颜色。下面的代码不能很好地工作，因为背景颜色并非总是正确设置的。我的意思是，应该将要设置给艺术家的颜色设置为跟踪，或者在艺术家选项卡中设置专辑的背景颜色，诸如此类。当我启动该应用程序时，没有设置背景色。

我该如何解决？

colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="app_bar_artist">#FFF29312</color>
    <color name="app_bar_album">#FFEDEFEB</color>
    <color name="app_bar_track">#FF3E86A0</color>
</resources>

main_activity.xml

<android.support.design.widget.AppBarLayout
    android:id="@+id/activity_main_app_bar_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_weight="20">

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

    <android.support.design.widget.TabLayout
        android:id="@+id/activity_main_tab_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/activity_main_app_bar_layout"
        app:tabGravity="fill"
        app:tabMode="fixed"/>

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

-

public class MainActivity extends AppCompatActivity {
    private AppBarLayout appbar;

    // others implementations here but not related to the problem.
    public void setTabLayout() {
        ArtistFragment artistFragment = new ArtistaFragment();
        AlbumFragment   albumFragment   = new AlbumFragment();
        TrackFragment  trackFragment  = new TrackFragment();

        artistFragment.setAppBarLayout(appbar);
        albumFragment.setAppBarLayout(appbar);
        trackFragment.setAppBarLayout(appbar);

        viewPagerAdapter.addFragment(artistFragment, getResources().getString(R.string.fragment_artist_title));
        viewPagerAdapter.addFragment(albumFragment,   getResources().getString(R.string.fragment_album_title));
        viewPagerAdapter.addFragment(trackFragment,  getResources().getString(R.string.fragment_track_title));

        viewPager.setAdapter(viewPagerAdapter);
        tabLayout.setupWithViewPager(viewPager);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        appbar    = findViewById(R.id.activity_main_app_bar_layout);
        // others implementations here but not related to the problem.
        setTabLayout();
    }
}

-

public class ArtistFragment extends Fragment {

    private AppBarLayout appBarLayout;

    public ArtistFragment() {}

    public void setAppBarLayout(AppBarLayout appBarLayout) {
        this.appBarLayout = appBarLayout;
    }

    private void setBackgroundColor() {
        appBarLayout.setBackgroundColor(getResources().getColor(R.color.app_bar_artist));
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_artist, container, false);
        setBackgroundColor();
        return view;
    }

}

-

public class AlbumFragment extends Fragment {

    private AppBarLayout appBarLayout;

    public AlbumFragment() {}

    public void setAppBarLayout(AppBarLayout appBarLayout) {
        this.appBarLayout = appBarLayout;
    }

    private void setBackgroundColor() {
        appBarLayout.setBackgroundColor(getResources().getColor(R.color.app_bar_album));
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_album, container, false);
        setBackgroundColor();
        return view;
    }

}

我没有发布TrackFragment，因为它与ArtistFragment和AlbumFragment几乎相同。

更改AppBar的背景颜色

0 个答案: