PercentRelativeLayout

public class PercentRelativeLayout extends RelativeLayout

Subclass of android.widget.RelativeLayout that supports percentage based dimensions and margins. You can specify dimension or a margin of child by using attributes with "Percent" suffix. Follow this example:

<androidx.percentlayout.widget.PercentRelativeLayout
        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">
    <ImageView
        app:layout_widthPercent="50%"
        app:layout_heightPercent="50%"
        app:layout_marginTopPercent="25%"
        app:layout_marginLeftPercent="25%"/>
</androidx.percentlayout.widget.PercentRelativeLayout>

• layout_widthPercent
• layout_heightPercent
• layout_marginPercent
• layout_marginLeftPercent
• layout_marginTopPercent
• layout_marginRightPercent
• layout_marginBottomPercent
• layout_marginStartPercent
• layout_marginEndPercent
• layout_aspectRatio

You can also make one dimension be a fraction of the other by setting only width or height and using layout_aspectRatio for the second one to be calculated automatically. For example, if you would like to achieve 16:9 aspect ratio, you can write:

    android:layout_width="300dp"
    app:layout_aspectRatio="178%"

Summary