Button half width of screen

Question

I have a single button in a linear layout. I want the button to take up half the width of its parent. Is there a way to do this in the layout xml.

Answer 1

Yep, the solution is very similar to that question, but you also want to set the weightSum of the parent LinearLayout:

<LinearLayout
    android:id="@+id/linearLayout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:gravity="center_horizontal"
    android:padding="6dp"
    android:weightSum="2">

    <Button
        android:id="@+id/buttonCollect"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:text="@string/hello"
        android:paddingLeft="8dp"
        android:paddingRight="8dp"
        android:layout_weight="1" />

</LinearLayout> 

Answer 2

Exactly the same as the question you posted, just use a dummy view instead:

<View 
android:weight="1"
android:layout_width="0dp"
android:layout_height="match_parent"/>

Answer 3

You need to set a 0.5 (half) weight, and set the width to 0.

<Button
    android:id="@+id/buttonCollect"
    android:layout_width="0dip"
    android:layout_weight="0.5"
    android:layout_height="match_parent"
    android:text="@string/hello"
    android:paddingLeft="8dp"
    android:paddingRight="8dp"/>

Answer 4

None of these solutions worked for me on Android L. I had to do wrap_content as below:

<Button
    android:layout_gravity="center"
    android:id="@+id/btnSignin"
    android:layout_width="wrap_content"
    android:paddingLeft="20dp"
    android:paddingRight="20dp"
    android:layout_height="wrap_content"
    android:text="@string/btn_signin"
    android:layout_marginBottom="@dimen/activity_vertical_margin" />