Rubymotion Layout Wrapper

README.md

Rubymotion Layout Wrapper

There's a lot of wrappers for Rubymotion already. I've been collecting my personal wrappers in the Loco namespace. I'm really starting to like this layout wrapper, so I thought I'd share it.

Usage

Include the loco.rb file in your Rubymotion project and include the Loco::UIView module in any of your custom UIViews.

class SampleView < UIView
  include Loco::UIView
end

When you initialize your view, just pass it a combination of parameters for the position and size.

• bottom
• height
• left
• right
• top
• width

Examples

# This view will be 300 x 200 and centered 
# horizontally and vertically in its superview.
@centeredView = SampleView.alloc.initWithFrame({
  height: 300,
  width: 200
})
@centeredView.backgroundColor = UIColor.greenColor

# This view will have the height of 100, left margin of 20, 
# right margin of 30, a flexible width, and will be 
# centered vertically in its superview.
@fixedMarginsView = SampleView.alloc.initWithFrame({
  height: 100,
  left: 20,
  right: 30
})
@fixedMarginsView.backgroundColor = UIColor.yellowColor
@centeredView.addSubview(@fixedMarginsView)

view.addSubview(@centeredView)

Missing Parameters

The console will yell at you if you don't include enough parameters to determine how to size and position the view. Example:

{height: 100, left: 20, top: 20} - The width can't be determined.

The console will also yell at you if you include parameters that may conflict with each other. Example:

{left: 20, right: 20, width: 200} - The width may conflict with the margins depending on the size of the superview.

Enjoy

I hope you can use it or at least learn something from it!

@brianpattison

loco.rb

module Loco

  module UIView
    # The position of the bottom edge,
    # relative to the superview's bottom edge.
    # @return [Integer]
    attr_accessor :bottom
    def bottom=(bottom)
      @bottom = bottom
      refresh_layout
    end

    # The height of the view.
    # @return [Integer]
    attr_accessor :height
    def height=(height)
      @height = height
      refresh_layout
    end

    # The position of the left edge,
    # relative to the superview's left edge.
    # @return [Integer]
    attr_accessor :left
    def left=(left)
      @left = left
      refresh_layout
    end

    # The position of the right edge,
    # relative to the superview's right edge.
    # @return [Integer]
    attr_accessor :right
    def right=(right)
      @right = right
      refresh_layout
    end

    # The position of the top edge,
    # relative to the superview's top edge.
    # @return [Integer]
    attr_accessor :top
    def top=(top)
      @top = top
      refresh_layout
    end

    # The width of the view.
    # @return [Integer]
    attr_accessor :width
    def width=(width)
      @width = width
      refresh_layout
    end

    # Create new instance from a hash of properties with values.
    # @param [Object] frame The CGRect or a Hash of properties for layout.
    def initWithFrame(frame)
      if frame.is_a? Hash
        # Set the initial property values from the given hash
        super(CGRect.new)
        frame.each do |key, value|
          self.send("#{key}=", value) if %w(bottom height left right top width).include?(key.to_s)
        end
      else
        super(frame)
      end
      self
    end

    # Refresh the layout based on bottom, left, right, top, and superview.
    # @param [UIView] superview
    def refresh_layout(superview=nil)
      # The view can't be positioned without being added to the superview first.
      superview ||= self.superview
      return if superview.nil?

      # Determine the original size, position, and autoresizing mask that should be used.
      if self.top && self.bottom
        if self.left && self.right
          # FW, FH
          @origin_x     = self.left
          @origin_y     = self.top
          @size_height  = superview.bounds.size.height - self.top - self.bottom
          @size_width   = superview.bounds.size.width - self.left - self.right
          @autoresizing = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight
        elsif self.left && self.width
          # FH, FRM
          @origin_x     = self.left
          @origin_y     = self.top
          @size_height  = superview.bounds.size.height - self.top - self.bottom
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleRightMargin
        elsif self.right && self.width
          # FH, FLM
          @origin_x     = superview.bounds.size.width - self.width - self.right
          @origin_y     = self.top
          @size_height  = superview.bounds.size.height - self.top - self.bottom
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin
        elsif self.width
          # FH, FLM, FRM
          @origin_x     = (superview.bounds.size.width - self.width) / 2
          @origin_y     = self.top
          @size_height  = superview.bounds.size.height - self.top - self.bottom
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin
        else
          # Needs More Params
          NSLog('%@<Loco::UIView> Not enough params to position and size the view.', self.class)
        end
      elsif self.top
        if self.left && self.right && self.height
          # FW, FBM
          @origin_x     = self.left
          @origin_y     = self.top
          @size_height  = self.height
          @size_width   = superview.bounds.size.width - self.left - self.right
          @autoresizing = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleBottomMargin
        elsif self.left && self.height && self.width
          # FBM, FRM
          @origin_x     = self.left
          @origin_y     = self.top
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleRightMargin
        elsif self.right && self.height && self.width
          # FBM, FLM
          @origin_x     = superview.bounds.size.width - self.width - self.right
          @origin_y     = self.top
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleLeftMargin
        elsif self.height && self.width
          # FLM, FRM, FBM
          @origin_x     = (superview.bounds.size.width - self.width) / 2
          @origin_y     = self.top
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin |UIViewAutoresizingFlexibleBottomMargin
        else
          # Needs More Params
          NSLog('%@<Loco::UIView> Not enough params to position and size the view.', self.class)
        end
      elsif self.bottom
        if self.left && self.right && self.height
          # FW, FTM
          @origin_x     = self.left
          @origin_y     = superview.bounds.size.height - self.height - self.bottom
          @size_height  = self.height
          @size_width   = superview.bounds.size.width - self.left - self.right
          @autoresizing = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleTopMargin
        elsif self.left && self.height && self.width
          # FTM, FRM
          @origin_x     = self.left
          @origin_y     = superview.bounds.size.height - self.height - self.bottom
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleRightMargin
        elsif self.right && self.height && self.width
          # FTM, FLM
          @origin_x     = superview.bounds.size.width - self.width - self.right
          @origin_y     = superview.bounds.size.height - self.height - self.bottom
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleLeftMargin
        elsif self.height && self.width
          # FLM, FRM, FTM
          @origin_x     = (superview.bounds.size.width - self.width) / 2
          @origin_y     = superview.bounds.size.height - self.height - self.bottom
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin |UIViewAutoresizingFlexibleTopMargin
        else
          # Needs More Params
          NSLog('%@<Loco::UIView> Not enough params to position and size the view.', self.class)
        end
      elsif self.left && self.right && self.height
        # FW, FTM, FBM
        @origin_x     = self.left
        @origin_y     = (superview.bounds.size.height - self.height) / 2
        @size_height  = self.height
        @size_width   = superview.bounds.size.width - self.left - self.right
        @autoresizing = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin
      elsif self.width && self.height
        if self.left
          # FTM, FBM, FRM
          @origin_x     = self.left
          @origin_y     = (superview.bounds.size.height - self.height) / 2
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleRightMargin
        elsif self.right
          # FTM, FBM, FLM
          @origin_x     = superview.bounds.size.width - self.width - self.right
          @origin_y     = (superview.bounds.size.height - self.height) / 2
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleLeftMargin
        else
          # FTM, FBM, FLM, FRM
          @origin_x     = (superview.bounds.size.width - self.width) / 2
          @origin_y     = (superview.bounds.size.height - self.height) / 2
          @size_height  = self.height
          @size_width   = self.width
          @autoresizing = UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin
        end
      else
        # Needs More Params
        NSLog('%@<Loco::UIView> Not enough params to position and size the view.', self.class)
      end

      # Warn of any possible conflicts
      if self.top && self.bottom && self.height
        NSLog('%@<Loco::UIView> `top`, `bottom`, and `height` may conflict with each other. Only two of the three should be set.', self.class)
        NSLog('%@<Loco::UIView> top: %@, bottom: %@, height: %@', self.class, self.top, self.bottom, self.height)
      end
      if self.left && self.right && self.width
        NSLog('%@<Loco::UIView> `left`, `right`, and `width` may conflict with each other. Only two of the three should be set.', self.class)
        NSLog('%@<Loco::UIView> left: %@, right: %@, width: %@', self.class, self.left, self.right, self.width)
      end

      if @origin_x && @origin_y && @size_width && @size_height && @autoresizing
        self.frame = [[@origin_x, @origin_y], [@size_width, @size_height]]
        self.autoresizingMask = @autoresizing
      end

      # Update the subviews
      self.subviews.each do |view|
        view.refresh_layout(self) if view.is_a? Loco::UIView
      end
    end

    # Fires when the superview changes.
    def willMoveToSuperview(superview)
      refresh_layout(superview)
    end
  end

end