android - Coordinatorlayout 中的 Recyclerview 切断最后一项

Question

我有一个底部导航栏和一个作为 fragment 容器的框架布局。因此，当单击底部导航栏上的图标时，上面的 fragment 会发生变化。

在其中一个 fragment 中，我有一个协调器布局、折叠工具栏和回收器 View 。目前，数据只是一个虚拟数据。

我遇到的问题是，每当该 fragment 第一次膨胀时，Recyclerview 工作正常并显示列表中的所有项目。但是当我更改 fragment 并再次回到该 fragment 时，Recyclerview 的最后一项被切断并隐藏在底部导航栏后面。

这是我的 activity_home_screen.xml 代码

<RelativeLayout 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"
tools:context="com.smartinc.livesportstv.activities.HomeScreen">

<android.support.design.widget.BottomNavigationView
    android:id="@+id/bottom_nav"
    android:layout_width="match_parent"
    android:layout_height="55dp"
    android:layout_alignParentBottom="true"
    android:layout_gravity="bottom"
    app:itemBackground="?attr/colorPrimary"
    app:itemIconTint="@drawable/selector_bottombar_item"
    app:itemTextColor="@drawable/selector_bottombar_item"
    app:menu="@menu/bottombar_menu" />

<FrameLayout
    android:id="@+id/frame_fragmentholder"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_above="@id/bottom_nav"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    />

这里是 fragment_events.xml

<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:fitsSystemWindows="true"
android:id="@+id/coordinator">

<android.support.design.widget.AppBarLayout
    android:id="@+id/app_bar"
    android:layout_width="match_parent"
    android:layout_height="120dp"
    >

    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:contentScrim="@color/colorPrimary"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        app:layout_scrollFlags="scroll|exitUntilCollapsed"
        app:title="Events"
        app:expandedTitleTextAppearance="@style/TransparentText"
        app:collapsedTitleTextAppearance="@style/Toolbar_text_black"
        app:collapsedTitleGravity="center_horizontal"
        android:paddingEnd="20dp"
        android:fitsSystemWindows="true"
        >

        <!-- You can add views that you want to appear on the
             collapsing toolbar here -->

        <TextView
            android:id="@+id/events_title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Events"
            android:textSize="30sp"
            android:textColor="@color/black"
            android:layout_marginTop="30dp"
            android:layout_marginStart="20dp"
            android:textStyle="bold"
            />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="29 March, Thursday"
            android:textSize="20sp"
            android:textColor="@color/grey_800"
            android:layout_marginTop="70dp"
            android:layout_marginStart="20dp"
            />

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:layout_collapseMode="pin"
            android:minHeight="?attr/actionBarSize"
            app:layout_scrollFlags="scroll|enterAlways"
            android:gravity="center_horizontal"
            app:popupTheme="@style/AppTheme"
            app:contentInsetLeft="0dp"
            app:contentInsetStart="0dp"
            />

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

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

<android.support.v7.widget.RecyclerView
    android:id="@+id/recycler_view_events"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    />


<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Request"
    android:textSize="17sp"
    android:layout_gravity="end"
    android:textColor="@color/colorPrimaryDark"
    android:padding="10dp"
    android:layout_marginEnd="10dp"
    android:layout_marginTop="5dp"
    />

这里是HomeScreen.java

public class HomeScreen extends AppCompatActivity {

private BottomNavigationView bottomNavigationView;

private String fragName = "";

@Override
public void startActivity(Intent intent) {
    super.startActivity(intent);
    Constants.overridePendingTransitionEnter(this);
}

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

    init();
    setMainFragment();
    setBottomNavigation();
}

private void init(){
    bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottom_nav);


}

private void setBottomNavigation(){
    bottomNavigationView.setOnNavigationItemSelectedListener(
            new BottomNavigationView.OnNavigationItemSelectedListener() {
                @Override
                public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                    switch (item.getItemId()) {
                        case R.id.bottombaritem_events:
                            if(!fragName.equals("events")) {
                                FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
                                ft.setCustomAnimations(R.anim.left_slide_in, R.anim.right_slide_out);
                                ft.replace(R.id.frame_fragmentholder, new EventsFragment());
                                ft.commit();
                                fragName = "events";
                            }
                            return true;
                        case R.id.bottombaritem_channels:
                            FragmentTransaction ft2 = getSupportFragmentManager().beginTransaction();
                            if(fragName.equals("events")) {
                                ft2.setCustomAnimations(R.anim.right_slide_in, R.anim.left_slide_out);
                            } else {
                                ft2.setCustomAnimations(R.anim.left_slide_in, R.anim.right_slide_out);
                            }

                            ft2.replace(R.id.frame_fragmentholder, new ChannelsFragment());
                            ft2.commit();
                            fragName = "channels";
                            return true;
                        case R.id.bottombaritem_more:
                            if(!fragName.equals("more")) {
                                FragmentTransaction ft3 = getSupportFragmentManager().beginTransaction();
                                ft3.setCustomAnimations(R.anim.right_slide_in, R.anim.left_slide_out);
                                ft3.replace(R.id.frame_fragmentholder, new MoreFragment());
                                ft3.commit();
                                fragName = "more";
                            }
                            return true;
                    }
                    return false;
                }
            });
}

private void setMainFragment(){
    fragName = "events";
    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    ft.replace(R.id.frame_fragmentholder, new EventsFragment());
    ft.commit();
}

@Override
public void onBackPressed() {
    super.onBackPressed();
    Constants.overridePendingTransitionExit(this);
}

}

这里是 EventsFragment.java

public class EventsFragment extends Fragment {

private RecyclerView mRecyclerView;
private ArrayList<String> mData;

private CollapsingToolbarLayout collapsing_toolbar;

private Context mContext;

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

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}

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

    mContext = getActivity();

    final CollapsingToolbarLayout collapsingToolbarLayout = (CollapsingToolbarLayout) view.findViewById(R.id.collapsing_toolbar);
    AppBarLayout appBarLayout = (AppBarLayout) view.findViewById(R.id.app_bar);
    appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
        boolean isShow = true;
        int scrollRange = -1;

        @Override
        public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
            if (scrollRange == -1) {
                scrollRange = appBarLayout.getTotalScrollRange();
            }
            if (scrollRange + verticalOffset == 0) {
                collapsingToolbarLayout.setTitle("Events");
                isShow = true;
            } else if(isShow) {
                collapsingToolbarLayout.setTitle(" ");//carefull there should a space between double quote otherwise it wont work
                isShow = false;
            }
        }
    });

    // Initialize the RecyclerView
    mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view_events);
    setUpRecyclerView();

    return view;
}

private void setUpRecyclerView() {
    LinearLayoutManager llm = new LinearLayoutManager(mContext);
    llm.setAutoMeasureEnabled(true);
    mRecyclerView.setLayoutManager(llm);

    EventsAdapter eventsAdapter = new EventsAdapter(mContext);
    mRecyclerView.setAdapter(eventsAdapter);
}

任何帮助将不胜感激。谢谢!

Answer 1

从事件 XML 中删除这一行。

android:fitsSystemWindows="true"

一切都会顺利进行。