I've got a CoordinatorLayout which contains a CollapsingToolbarLayout and a RecyclerView. Everything looks the way it's supposed to, except that when I try to scroll to the last item programmatically, it doesn't go all the way to the bottom. Instead, it does this:
I don't think this is a clipping problem, since the bottom item is fully there if I scroll down:
Here's the main layout:
<?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"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:id="@+id/app_bar"
android:layout_width="match_parent"
android:layout_height="150dp"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginStart="16dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:toolbarId="@+id/toolbar">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:contentInsetStart="72dp"
app:popupTheme="@style/AppTheme.PopupOverlay"/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginBottom="@dimen/recyclerview_bottom_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
And here's the code that goes with the screencaps above:
class TestActivity : AppCompatActivity() {
private val itemNames = listOf("top item", "next item", "yada", "yada yada", "yada yada yada", "second last item", "last item")
private val selectedPosition = itemNames.size - 1
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.recyclerview_with_collapsing_toolbar)
setSupportActionBar(toolbar)
supportActionBar?.setTitle(R.string.some_title)
val recyclerView = findViewById<RecyclerView>(R.id.recycler_view)
recyclerView.setHasFixedSize(true)
val layoutManager = LinearLayoutManager(this)
recyclerView.layoutManager = layoutManager
recyclerView.adapter = MyAdapter()
// try to scroll to the initial selected position
recyclerView.scrollToPosition(selectedPosition)
// layoutManager.scrollToPosition(selectedPosition)
// layoutManager.scrollToPositionWithOffset(selectedPosition, resources.getDimensionPixelOffset(R.dimen.item_height))
// recyclerView.post {
// recyclerView.smoothScrollToPosition(selectedPosition)
// }
}
inner class MyAdapter: RecyclerView.Adapter<MyViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, itemType: Int): MyViewHolder {
val view = LayoutInflater.from(parent.context).inflate(R.layout.item_layout, parent, false)
return MyViewHolder(view)
}
override fun getItemCount(): Int {
return itemNames.size
}
override fun onBindViewHolder(vh: MyViewHolder, position: Int) {
vh.words.text = itemNames[position]
if (selectedPosition == position) {
vh.parent.setBackgroundColor(Color.MAGENTA)
} else {
vh.parent.setBackgroundColor(Color.BLACK)
}
}
}
inner class MyViewHolder(itemView: View): RecyclerView.ViewHolder(itemView) {
val parent = itemView
val words: TextView = itemView.findViewById(R.id.some_text)
}
}
Additional notes:
-
If I get rid of the
CollapsingToolbarLayoutthen it does show the entire last item. -
I've left some of my other attempts in the code above (commented out). None of them worked.
-
This example just involves a short static list and always scrolls to the same item, but the code I'm actually working on is a bit more complicated.
-
The designer really wants everything to look exactly as designed, and I'm not free to change the visual design.
How can I scroll to the last item in a RecyclerView that's inside a layout with a collapsing toolbar?
from Scrolling to last item of a recyclerview with a collapsing toolbar


No comments:
Post a Comment