Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Android

Size one element to fill the remaining space on the screen

I'm working on an app that has a few EditText elements and buttons. It also has a NestedScrollView that I would like to size to fill whatever space remains on the screen. It should stretch from the bottom of my nameSaveButton to my startDrawingButton. Can anyone help me with this?

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="10dp"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/nameEditText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:ems="10"
        android:hint="@string/name_entry_hint"
        android:inputType="textPersonName"
        android:maxLength="35"
        android:textSize="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/scoreEditText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:ems="10"
        android:hint="@string/score_entry_hint"
        android:inputType="numberSigned"
        android:textSize="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/nameEditText" />

    <Button
        android:id="@+id/nameSaveButton"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:text="@string/entry_save_button"
        android:textSize="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/scoreEditText" />

    <android.support.v4.widget.NestedScrollView
        android:id="@+id/namesListView"
        android:layout_width="match_parent"
        android:layout_height="400dp"
        android:layout_weight="1"
        android:fillViewport="true"
        android:background="@color/colorPrimary"
        app:layout_constraintTop_toBottomOf="@id/nameSaveButton">

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

    </android.support.v4.widget.NestedScrollView>

    <Button
        android:id="@+id/startDrawingButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:text="Button"
        android:textSize="24dp"
        app:layout_constraintBottom_toBottomOf="parent" />

</android.support.constraint.ConstraintLayout>

1 Answer

I found an answer. Hopefully, it will be useful to someone else. Here is my activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="10dp"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/nameEditText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:ems="10"
        android:hint="@string/name_entry_hint"
        android:inputType="textPersonName"
        android:maxLength="35"
        android:textSize="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/scoreEditText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:ems="10"
        android:hint="@string/score_entry_hint"
        android:inputType="numberSigned"
        android:textSize="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/nameEditText" />

    <Button
        android:id="@+id/nameSaveButton"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:text="@string/entry_save_button"
        android:textSize="24dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/scoreEditText" />

    <android.support.v4.widget.NestedScrollView
        android:id="@+id/namesListView"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:fillViewport="true"
        android:background="@color/colorPrimary"
        app:layout_constraintTop_toBottomOf="@id/nameSaveButton"
        app:layout_constraintBottom_toTopOf="@id/startDrawingButton">

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

    </android.support.v4.widget.NestedScrollView>

    <Button
        android:id="@+id/startDrawingButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="0"
        android:text="Button"
        android:textSize="24dp"
        app:layout_constraintBottom_toBottomOf="parent" />

</android.support.constraint.ConstraintLayout>

The actual fix is applied to the NestedScrollView. You'll notice that I've added two constraints: app:layout_constraintTop_toBottomOf="@id/nameSaveButton" and app:layout_constraintBottom_toTopOf="@id/startDrawingButton". Then I set the android:layout_height="0dp" to force Android to calculate the height of the NestedScrollView at runtime.