Android published ConstraintLayout 1.1.0 on the google maven repository. One of the more interesting additions to this release is Circular Positioning. Circular positioning allows you to constrain a widget center relative to another widget center, at an angle and a distance. This allows you to position a widget on a circle.
Add ConstraintLayout to your project
To use ConstraintLayout in your project, proceed as follows: 1.Ensure you have the maven.google.com repository declared in your project-level build.gradle file:
repositories {
maven {
url 'https://maven.google.com'
}
}
2.Add the library as a dependency in the same build.gradle file:
dependencies {
....
compile 'com.android.support.constraint:constraint-layout:1.1.0-beta3'
}
Example Circular positioning
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
...
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:id="@+id/buttonA"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button A"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/buttonB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button B"
app:layout_constraintCircle="@id/buttonA"
app:layout_constraintCircleAngle="45"
app:layout_constraintCircleRadius="100dp"
/>
</android.support.constraint.ConstraintLayout>
The following attributes can be used:
layout_constraintCircle: references another widget id.layout_constraintCircleRadius: the distance to the other widget centerlayout_constraintCircleAngle: which angle the widget should be at (in degrees, from 0 to 360).