TabLayout header hides first item on a ListView in a fragment

问题:

i've got my Android skills a bit rusty, and i hope someone can help me with this. I've got a TabLayout with a ViewPager to swipe the same Fragment with different data in a ListView. Everything is working ok, but I've got a problem. The tabs header text hides a part of the Fragment, causing the first element of the ListView being hiden behind. I really have tried to find a solution for this problem but i couldn't, I'm sure it must be something simple but no solution. If you need more info, please ask. I've got this activity layout:

<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.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/ThemeOverlay.AppCompat.Dark.ActionBar"/>  </android.support.design.widget.AppBarLayout>   <android.support.v4.view.ViewPager     android:id="@+id/pager"     android:layout_width="match_parent"     android:layout_height="fill_parent"     /> </android.support.design.widget.CoordinatorLayout> 

This is the activity code:

public class ParadasActivity extends AppCompatActivity             implements LoaderManager.LoaderCallbacks<Cursor>{ ... @Override public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor cursor) {     TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);      while (cursor.moveToNext()) {         Tab tab =tabLayout.newTab();         tabLayout.addTab(tab);     } 

Fragment code:

@Override public View onCreateView(LayoutInflater inflater, ViewGroup container,                          Bundle savedInstanceState) {      final View view = inflater.inflate(R.layout.fragment_paradas, container, false);     paradasAdapter = new ParadasAdapter(getActivity(), null, 0);     mListView = (ListView) view.findViewById(R.id.listview_paradas);     mListView.setAdapter(paradasAdapter);      return view; } 

Fragment layout:

<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"          android:id="@+id/fragment_paradas"          tools:context="com.pikohsoft.android.tussantander.ParadasActivityFragment"          tools:showIn="@layout/activity_paradas"> <ListView android:id="@+id/listview_paradas"           android:layout_height="match_parent"           android:layout_width="match_parent"     /> 

And the code for the pager adapter:

public class SublineasPagerAdapter extends FragmentStatePagerAdapter { int mNumOfTabs;   public SublineasPagerAdapter(FragmentManager fm, int NumOfTabs, Bundle arguments) {     super(fm);     this.mNumOfTabs = NumOfTabs; }  @Override public Fragment getItem(int position) {     ParadasActivityFragment tab1 = new ParadasActivityFragment();     return tab1; }  @Override public int getCount() {     return mNumOfTabs; } 

回答1:

When you use CoordinatorLayout it's Extend from ViewGroup so when you put your ViewPager (or other kinds of Layout) in Z-order they overlap (and you see they come on top of each other) so by using

app:layout_behavior="@string/appbar_scrolling_view_behavior"

You tell to CoordinatorLayout hey it's a bit different !!! and it look at your AppBarLayout and put this layout below appbar.

文章来源: TabLayout header hides first item on a ListView in a fragment