CardView inside RecyclerView has extra margins

Question

I am using a CardView as element inside a RecyclerView. When doing so android automatically generates margins between the cardView and the screen and between different cardViews.

<android.support.v7.widget.CardView 
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="wrap_content"
android:background="@color/galleryCardBGColor"
app:cardCornerRadius="2dp" >

<android.support.v7.widget.RecyclerView
    android:id="@+id/my_recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:scrollbars="vertical" />

I followed the instructions in the link to integrate them into my project: using-recyclerview-and-cardview-in-eclipse-adt

I had been previously using a linearlayout for the list element :

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

This was working perfectly fine, with no margins whatsoever between the list elements. I have now just placed the linear layout inside the cardView which has resulted in extra margins.

The reason being that i want to provide exact margins to these elements, and any margins I supply now is being added over to this preexisting margins. I have tried supplying zero/negative paddings/margins to the cardView element but none of these work.

Any idea, I can remove these margins or otherwise know exactly how much margin is being added.

Answer 1

did you check if it is margin or padding? (Dev Options / show layout bounds)

CardView adds padding in platforms pre-L to draw shadows. In L, unless you set useCompatPadding=true, there should not be any gap.

Adding negative margins (although it is ugly) should work. If it is not, please add some more code on how you are adding them and how you are setting up the RecyclerView.