Using ratios on both dimensions with ConstraintLayout to display 3 squares of same size

Question

I want to display 3 squares of same dimensions using ConstraintLayout. The size of the square must be 1/3 of screen height. I would like to know how to do it using ConstraintLayout.

I started with this code:

<android.support.constraint.ConstraintLayout
    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">

    <View
        android:id="@+id/view1"
        android:layout_width="wrap_content"
        android:layout_height="0dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/view2"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintVertical_chainStyle="spread"
        android:background="#ff0000" />

    <View
        android:id="@+id/view2"
        android:layout_width="wrap_content"
        android:layout_height="0dp"
        app:layout_constraintTop_toBottomOf="@id/view1"
        app:layout_constraintBottom_toTopOf="@+id/view3"
        app:layout_constraintLeft_toLeftOf="parent"
        android:background="#00ff00" />

    <View
        android:id="@+id/view3"
        android:layout_width="wrap_content"
        android:layout_height="0dp"
        app:layout_constraintTop_toBottomOf="@id/view2"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        android:background="#0000ff" />


</android.support.constraint.ConstraintLayout>

With this code I'm getting the desired height but I want to use ConstraintLayout Ratio feature to constraint the width to 1:1

I tried with this code:

<android.support.constraint.ConstraintLayout
    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">

    <View
        android:id="@+id/view1"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/view2"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintVertical_chainStyle="spread"
        app:layout_constraintDimensionRatio="W,1:1"
        android:background="#ff0000" />

    <View
        android:id="@+id/view2"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintTop_toBottomOf="@id/view1"
        app:layout_constraintBottom_toTopOf="@+id/view3"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintDimensionRatio="W,1:1"
        android:background="#00ff00" />

    <View
        android:id="@+id/view3"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintTop_toBottomOf="@id/view2"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintDimensionRatio="W,1:1"
        android:background="#0000ff" />

</android.support.constraint.ConstraintLayout>

How can I do to fix theses constraints and display correctly 3 squares of same size? I only want to use ConstraintLayout features if possible.

Thanks

Answer 1

I'll post an implementation with guidelines:

<?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"
        tools:layout_editor_absoluteY="81dp"
        tools:layout_editor_absoluteX="0dp">

    <android.support.constraint.Guideline
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/guideline1"
            android:orientation="horizontal"
            app:layout_constraintGuide_percent="0.33"/>

    <android.support.constraint.Guideline
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/guideline2"
            android:orientation="horizontal"
            app:layout_constraintGuide_percent="0.66"/>

    <TextView
            android:id="@+id/view1"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="#ff0000"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintVertical_bias="0.5"
            app:layout_constraintHorizontal_bias="0.5"
            app:layout_constraintBottom_toTopOf="@+id/guideline1"
            android:layout_marginBottom="0dp"
            android:layout_marginLeft="0dp"
            app:layout_constraintDimensionRatio="1:1"/>

    <TextView
            android:id="@+id/view2"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="#00ff00"
            app:layout_constraintTop_toBottomOf="@id/guideline1"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintHorizontal_weight="1"
            app:layout_constraintVertical_bias="0.5"
            app:layout_constraintHorizontal_bias="0.5"
            app:layout_constraintBottom_toTopOf="@id/guideline2"
            app:layout_constraintDimensionRatio="1:1"/>

    <TextView
            android:id="@+id/view3"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="#0000ff"
            app:layout_constraintTop_toBottomOf="@id/guideline2"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintHorizontal_weight="1"
            app:layout_constraintVertical_bias="0.5"
            app:layout_constraintHorizontal_bias="0.5"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintDimensionRatio="1:1"/>


</android.support.constraint.ConstraintLayout>

Answer 2

Align View2 and View3's horizontal margins to View1 instead of Parent:

<View
    android:id="@+id/view1"
    android:background="#ff0000"
    android:layout_height="0dp"
    android:layout_width="0dp"
    app:layout_constraintTop_toTopOf="parent"
    app:layout_constraintBottom_toTopOf="@+id/view2"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintDimensionRatio="1:1"
    app:layout_constraintVertical_chainStyle="spread"
    app:layout_constraintHorizontal_chainStyle="spread"/>

<View
    android:id="@+id/view2"
    android:background="#00ff00"
    android:layout_height="0dp"
    android:layout_width="0dp"
    app:layout_constraintTop_toBottomOf="@id/view1"
    app:layout_constraintBottom_toTopOf="@id/view3"
    app:layout_constraintLeft_toLeftOf="@id/view1"
    app:layout_constraintRight_toRightOf="@id/view1"
    app:layout_constraintDimensionRatio="1:1"/>

<View
    android:id="@+id/view3"
    android:background="#0000ff"
    android:layout_height="0dp"
    android:layout_width="0dp"
    app:layout_constraintTop_toBottomOf="@id/view2"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="@id/view1"
    app:layout_constraintRight_toRightOf="@id/view1"
    app:layout_constraintDimensionRatio="1:1"/>

Note the layout_constraintLeft_toLeftOf and layout_constraintRight_toRightOf of View2 and View3 are set to @id/view1 instead of parent.

(I added layout_constraintHorizontal_chainStyle="spread" to allow the chain centered horizontally. You could change the horizontal constraints of View1 to decide whether to align to the left, center or right.)