Common Attributes

These attributes are available for all view types in SwiftJsonUI.

Platform Support

• ✅ UIKit: Full support for all attributes
• ✅ SwiftUI: Most attributes supported (see individual notes)
• ✅ Jetpack Compose: Core attributes supported with modifiers
• ✅ Android XML: Attributes mapped to Android view attributes
  • See KotlinJsonUI XML Support for detailed mappings

Attribute Reference

attribute name	UIKit	SwiftUI	XML	type in json	details	remarks
id	✅	✅	✅	string	ID for the view. Should be unique within the view file including 'include' and 'style' files
type	✅	✅	❌	string	Name of the view type. Pre-defined types listed in View Types
include	✅	✅	❌	string	File name to include
style	✅	✅	❌	string	Style file name to apply
propertyName	✅	❌	❌	string	Alternative property name for binding	UIKit only
binding	✅	❌	❌	string/dict	Data binding key. Chain with '.' like 'teacher.student.name'	UIKit only
tag	✅	❌	❌	integer	View tag for identification	UIKit only
visibility	✅	✅	✅	string	View visibility: visible, invisible, gone. Default: visible
shadow	✅	✅	✅	string/dict	Shadow configuration. String: "color|offsetX|offsetY|opacity|radius" or dict with keys
background	✅	✅	✅	string	Background color (hex string e.g. #000000)
tapBackground	✅	✅	❌	string	Background color when tapped
userInteractionEnabled	✅	✅	✅	boolean	Enable user interaction
cornerRadius	✅	✅	✅	float	Corner radius
borderColor	✅	✅	✅	string	Border color
borderWidth	✅	✅	✅	float	Border width
clipToBounds	✅	✅	✅	boolean	Clip content to bounds
hidden	✅	✅	✅	boolean	Hide view
alpha	✅	✅	✅	float	View opacity (0.0 to 1.0)
rect	✅	❌	❌	array	Direct frame [x, y, width, height]. Disables auto layout	UIKit only
indexBelow	✅	✅	❌	string	Insert below specified view ID
indexAbove	✅	✅	❌	string	Insert above specified view ID
paddings	✅	✅	✅	array	Padding array [all] or [v,h] or [top,h,bottom] or [top,left,bottom,right]
paddingLeft	✅	✅	✅	float	Left padding
paddingRight	✅	✅	✅	float	Right padding
paddingTop	✅	✅	✅	float	Top padding
paddingBottom	✅	✅	✅	float	Bottom padding
margins	✅	✅	✅	array	Margin array [all] or [v,h] or [top,h,bottom] or [top,left,bottom,right]
leftMargin	✅	✅	✅	float	Left margin
rightMargin	✅	✅	✅	float	Right margin
topMargin	✅	✅	✅	float	Top margin
bottomMargin	✅	✅	✅	float	Bottom margin
minLeftMargin	✅	❌	❌	float	Minimum left margin	UIKit only
minRightMargin	✅	❌	❌	float	Minimum right margin	UIKit only
minTopMargin	✅	❌	❌	float	Minimum top margin	UIKit only
minBottomMargin	✅	❌	❌	float	Minimum bottom margin	UIKit only
maxLeftMargin	✅	❌	❌	float	Maximum left margin	UIKit only
maxRightMargin	✅	❌	❌	float	Maximum right margin	UIKit only
maxTopMargin	✅	❌	❌	float	Maximum top margin	UIKit only
maxBottomMargin	✅	❌	❌	float	Maximum bottom margin	UIKit only
centerInParent	✅	✅	✅	boolean	Center view in parent
centerVertical	✅	✅	✅	boolean	Center vertically in parent
centerHorizontal	✅	✅	✅	boolean	Center horizontally in parent
alignTop	✅	✅	✅	boolean	Align to top of parent
alignBottom	✅	✅	✅	boolean	Align to bottom of parent
alignLeft	✅	✅	✅	boolean	Align to left of parent
alignRight	✅	✅	✅	boolean	Align to right of parent
alignTopOfView	✅	✅	✅	string	Position above specified view ID
alignBottomOfView	✅	✅	✅	string	Position below specified view ID
alignLeftOfView	✅	✅	✅	string	Position to left of specified view ID
alignRightOfView	✅	✅	✅	string	Position to right of specified view ID
alignTopView	✅	✅	✅	string	Align top edge with specified view
alignBottomView	✅	✅	✅	string	Align bottom edge with specified view
alignLeftView	✅	✅	✅	string	Align left edge with specified view
alignRightView	✅	✅	✅	string	Align right edge with specified view
alignCenterVerticalView	✅	✅	✅	string	Align vertical center with specified view
alignCenterHorizontalView	✅	✅	✅	string	Align horizontal center with specified view
width	✅	✅	✅	float/string	Required. Width: matchParent, wrapContent, or number
height	✅	✅	✅	float/string	Required. Height: matchParent, wrapContent, or number
minWidth	✅	✅	❌	float	Minimum width
minHeight	✅	✅	❌	float	Minimum height
maxWidth	✅	✅	❌	float	Maximum width
maxHeight	✅	✅	❌	float	Maximum height
widthWeight	✅	❌	❌	float	Width ratio to parent	UIKit only
heightWeight	✅	❌	❌	float	Height ratio to parent	UIKit only
aspectWidth	✅	✅	❌	float	Width aspect ratio
aspectHeight	✅	✅	❌	float	Height aspect ratio
maxWidthWeight	✅	❌	❌	float	Maximum width ratio to parent	UIKit only
maxHeightWeight	✅	❌	❌	float	Maximum height ratio to parent	UIKit only
minWidthWeight	✅	❌	❌	float	Minimum width ratio to parent	UIKit only
minHeightWeight	✅	❌	❌	float	Minimum height ratio to parent	UIKit only
weight	✅	✅	✅	float	Layout weight for orientation layouts
compressHorizontal	✅	❌	❌	string	Horizontal compression resistance: Required, High, Low, Fit	UIKit only
compressVertical	✅	❌	❌	string	Vertical compression resistance: Required, High, Low, Fit	UIKit only
hugHorizontal	✅	❌	❌	string	Horizontal content hugging: Required, High, Low, Fit	UIKit only
hugVertical	✅	❌	❌	string	Vertical content hugging: Required, High, Low, Fit	UIKit only

Android XML Attribute Mappings

When using KotlinJsonUI's XML generation, common attributes are mapped as follows:

Layout Attributes

• width → android:layout_width (matchParent→match_parent, wrapContent→wrap_content)
• height → android:layout_height (matchParent→match_parent, wrapContent→wrap_content)
• padding/paddings → android:padding (individual padding values)
• margins → android:layout_margin (individual margin values)
• visibility → android:visibility (visible, invisible, gone)
• alpha → android:alpha (0.0-1.0)

Style Attributes

• background → android:background (colors or drawable resources)
• cornerRadius → Generated drawable with rounded corners
• borderWidth/borderColor → Generated drawable with border
• shadow → android:elevation (for Material Design shadows)

Alignment Attributes

• centerInParent → android:layout_centerInParent (RelativeLayout)
• alignTop/alignBottom → android:layout_alignParentTop/Bottom (RelativeLayout)
• weight → android:layout_weight (LinearLayout)

For complete XML mapping details, see KotlinJsonUI XML Support