android - CardView has lost margin when inflating

Question

In my activity, I am setting the layout activity_main onCreate. I am then wanting to inflate my CardView for each of the items in my array.

So far, I've got everything loaded, however my CardView's have lost their margin. When added to the layout through XML, the margin works, but when its inflated as a separate XML file the margin is lost.

I am inflating the activity_main_card like so:

LinearLayout item = (LinearLayout)findViewById(R.id.card_holder);
View child = getLayoutInflater().inflate(R.layout.activity_main_card, null);
item.addView(child);

In the activity_main_card, my XML is as follows:

<android.support.v7.widget.CardView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:id="@+id/card_view"
    android:layout_gravity="center"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    card_view:cardCornerRadius="2dp"
    android:layout_marginBottom="16dp">

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <ImageView
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:scaleType="fitCenter"
            android:background="@drawable/cin"/>

        <LinearLayout
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:orientation="vertical"
             android:padding="16dp">

             <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textSize="20sp"
                android:textStyle="bold"
                android:textColor="@color/dark_grey"/>

             <TextView
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:textSize="12sp"
                 android:textStyle="normal"
                 android:textColor="@color/grey_500"/>

        </LinearLayout>
    </LinearLayout>
</android.support.v7.widget.CardView>

Can anyone point me in the direction where I am going wrong?

Answer 1

You're passing in null as the parent ViewGroup parameter to inflate(). This will cause all layout_* attributes to be ignored, as the inflater has no idea which attributes are valid for the container in which it will be placed (i.e. it has no idea which LayoutParams type to set on the View).

View child = getLayoutInflater().inflate(R.layout.activity_main_card, null);

should be

View child = getLayoutInflater().inflate(R.layout.activity_main_card, item, false);

For more info, see this great article about it -- it's a common mistake.