Sprite:setLayoutConstraints

From GiderosMobile



Available since: Gideros 2018.9

Class: Sprite

Description

This function specify the child placement rules within the grid defined on its parent by Sprite:setLayoutParameters.

Gideros layout system is heavily based on Java GridBagLayout principle. See here for more explanation: https://www.math.uni-hamburg.de/doc/java/tutorial/uiswing/layout/gridbag.html

The constraint table can contain the following fields:

  • gridx: The 0-based index of the column the child must be placed into
  • gridy: The 0-based index of the row the child must be placed into
  • gridwidth: The number of column this child will take
  • gridheight: The number of row this child will take
  • weightx: The horizontal weight of the child. Used to distribute extra space among children
  • weighty: The vertical weight of the child. Used to distribute extra space among children
  • anchor: Defines where the child should be placed inside its grid space.

Can be Sprite.LAYOUT_ANCHOR_NORTHWEST, Sprite.LAYOUT_ANCHOR_NORTH, Sprite.LAYOUT_ANCHOR_NORTHEAST, Sprite.LAYOUT_ANCHOR_WEST, Sprite.LAYOUT_ANCHOR_CENTER, Sprite.LAYOUT_ANCHOR_EAST, Sprite.LAYOUT_ANCHOR_SOUTHWEST, Sprite.LAYOUT_ANCHOR_SOUTH or Sprite.LAYOUT_ANCHOR_SOUTHEAST

  • anchorx: Specify relative placement the of child on X axis. anchor mustn't be set since 2020.7
  • anchory: Specify relative placement the of child on Y axis. anchor mustn't be set since 2020.7
  • fill: In which directions the child should be expanded to fit the grid space.

Can be Sprite.LAYOUT_FILL_NONE, Sprite.LAYOUT_FILL_HORIZONTAL, Sprite.LAYOUT_FILL_VERTICAL or Sprite.LAYOUT_FILL_BOTH

  • ipadx: Internal horizontal padding
  • ipady: Internal vertical padding
  • minWidth: Minimum width
  • minHeight: Minimum height
  • prefWidth: Preferred width
  • prefHeight: Preferred height
  • insetTop: the top margin
  • insetLeft: the left margin
  • insetBottom: the bottom margin
  • insetRight: the right margin
  • insets: sets the above four margins to the same value at once. since 2020.7


Specifying a nil table will clear layout constraints.
When a Sprite is resized by the layout system, an Event.LAYOUT_RESIZED is triggered.


Sprite:setLayoutConstraints(constraints)

Parameters

constraints: (table) Table of layout constraints.

Examples

Example: pixels


-- LAYOUT CONSTRAINTS @Nanocore
-- BUTTONS HOLDER
local myholder = Pixel.new(0x0, 0.5, 256, 256)
myholder:setPosition(8, 8)
myholder:setLayoutParameters({
	columnWeights = {1, 1, 1}, -- 3 columns
	rowWeights = {1, 1, 1, 1}, -- 4 rows
	columnWidths = {32, 32, 32}, -- min columns width
	rowHeights = {32, 32, 32, 32}, -- min rows width
})

-- BUTTONS
local mybtn1 = Pixel.new(0xff0000, 1, 32, 32)
mybtn1:setLayoutConstraints({
	gridx = 0,
	gridy = 0,
	gridwidth = 2,
	gridheight = 2,
	anchor = Sprite.LAYOUT_ANCHOR_NORTHWEST,
	fill = Sprite.LAYOUT_FILL_BOTH,
})
myholder:addChild(mybtn1)

local mybtn2 = Pixel.new(0x00ff00, 1, 32, 32)
mybtn2:setLayoutConstraints({
	gridx = 1,
	gridy = 2,
	gridwidth = 1,
	anchor = Sprite.LAYOUT_ANCHOR_NORTHWEST,
	fill = Sprite.LAYOUT_FILL_VERTICAL,
})
myholder:addChild(mybtn2)

local mybtn3 = Pixel.new(0x0000ff, 1, 32, 32)
mybtn3:setLayoutConstraints({
	gridx = 2,
	gridy = 3,
	gridwidth = 1,
	anchor = Sprite.LAYOUT_ANCHOR_NORTHWEST,
	fill = Sprite.LAYOUT_FILL_BOTH,
})
myholder:addChild(mybtn3)

-- ADD TO STAGE
stage:addChild(myholder)