Width and height

Width specifies the width of the node’s border box, which is its content plus padding and border. Height does the same for the other axis.

Both accept the following values:

Auto (default): The size is computed from the node’s content, whether that is other children or a measure function.

Points: An absolute size. Depending on other properties, such as flex grow and shrink, this may or may not be the final size.

Percentage: A fraction of the containing block’s width or height.

node.setWidth(50);
node.setHeight("50%");
node.setWidth("auto");