The Markaby::Builder class is the central gear in the system. When using from Ruby code, this is the only class you need to instantiate directly.
mab = Markaby::Builder.new mab.html do head { title "Boats.com" } body do h1 "Boats.com has great deals" ul do li "$49 for a canoe" li "$39 for a raft" li "$29 for a huge boot that floats and can fit 5 people" end end end puts mab.to_s
# File lib/markaby/builder.rb, line 40 def self.ignore_helpers(*helpers) ignored_helpers.concat helpers end
# File lib/markaby/builder.rb, line 36 def self.ignored_helpers @@ignored_helpers ||= [] end
Create a Markaby builder object. Pass in a
hash of variable assignments to assigns
which will be
available as instance variables inside tag construction blocks. If an
object is passed in to helpers
, its methods will be available
from those same blocks.
Pass in a block
to new and the block will be evaluated.
mab = Markaby::Builder.new { html do body do h1 "Matching Mole" end end }
# File lib/markaby/builder.rb, line 61 def initialize(assigns = {}, helpers = nil, &block) @streams = [[]] @assigns = assigns @elements = {} @@default.each do |k, v| instance_variable_set("@#{k}", @assigns[k] || v) end if helpers.nil? @helpers = nil else @helpers = helpers.dup for iv in helpers.instance_variables instance_variable_set(iv, helpers.instance_variable_get(iv)) end end unless assigns.nil? || assigns.empty? for iv, val in assigns instance_variable_set("@#{iv}", val) unless @helpers.nil? @helpers.instance_variable_set("@#{iv}", val) end end end @builder = ::Builder::XmlMarkup.new(:indent => @indent, :target => @streams.last) class << @builder attr_accessor :target, :level end if block text(capture(&block)) end end
# File lib/markaby/builder.rb, line 32 def self.set(option, value) @@default[option] = value end
Emulate ERB to satisfy helpers like form_for
.
# File lib/markaby/builder.rb, line 112 def _erbout; self end
Captures the HTML code built inside the block
. This is done
by creating a new stream for the builder object, running the block and
passing back its stream as a string.
>> Markaby::Builder.new.capture { h1 "TEST"; h2 "CAPTURE ME" } => "<h1>TITLE</h1>\n<h2>CAPTURE ME</h2>\n"
# File lib/markaby/builder.rb, line 120 def capture(&block) @streams.push(builder.target = []) @builder.level += 1 str = instance_eval(&block) str = @streams.last.join if @streams.last.any? @streams.pop @builder.level -= 1 builder.target = @streams.last str end
Content_for will store the given block in an instance variable for later use in another template or in the layout.
The name of the instance variable is content_for_<name> to stay consistent with @content_for_layout which is used by ActionView's layouts.
Example:
content_for("header") do h1 "Half Shark and Half Lion" end
If used several times, the variable will contain all the parts concatenated.
# File lib/markaby/rails.rb, line 40 def content_for(name, &block) @helpers.assigns["content_for_#{name}"] = eval("@content_for_#{name} = (@content_for_#{name} || '') + capture(&block)") end
Builds a head tag. Adds a meta
tag inside with Content-Type
set to text/html; charset=utf-8
.
# File lib/markaby/builder.rb, line 230 def head(*args, &block) tag!(:head, *args) do tag!(:meta, "http-equiv" => "Content-Type", "content" => "text/html; charset=utf-8") if @output_meta_tag instance_eval(&block) end end
Every HTML tag method goes through an #html_tag call. So, calling
div
is equivalent to calling html_tag(:div)
. All
HTML tags in Markaby's list are given generated wrappers for this
method.
If the @auto_validation setting is on, this method will check for many common mistakes which could lead to invalid XHTML.
# File lib/markaby/builder.rb, line 202 def html_tag(sym, *args, &block) if @auto_validation and @tagset.self_closing.include?(sym) and block raise InvalidXhtmlError, "the `\#{sym}' element is self-closing, please remove the block" end if args.empty? and block.nil? and not NO_PROXY.include?(sym) return CssProxy.new do |args, block| if @tagset.forms.include?(sym) and args.last.respond_to?(:to_hash) and args.last[:id] args.last[:name] ||= args.last[:id] end tag!(sym, *args, &block) end end if not @tagset.self_closing.include?(sym) and args.first.respond_to?(:to_hash) block ||= proc{} end tag!(sym, *args, &block) end
This method is used to intercept calls to helper methods and instance variables. Here is the order of interception:
If sym
is a helper method, the helper method is called and
output to the stream.
If sym
is a Builder::XmlMarkup method, it is passed on to the
builder object.
If sym
is also the name of an instance variable, the value of
the instance variable is returned.
If sym
has come this far and no tagset
is found,
sym
and its arguments are passed to tag!
If a tagset is found, though, NoMethodError
is raised.
#method_missing used to be the lynchpin in Markaby, but it's no longer used to handle HTML tags. See #html_tag for that.
# File lib/markaby/builder.rb, line 177 def method_missing(sym, *args, &block) if @helpers.respond_to?(sym, true) && !self.class.ignored_helpers.include?(sym) r = @helpers.send(sym, *args, &block) if @output_helpers and r.respond_to? :to_str fragment { @builder << r } else r end elsif ::Builder::XmlMarkup.instance_methods.include?(sym.to_s) @builder.__send__(sym, *args, &block) elsif instance_variables.include?("@#{sym}") instance_variable_get("@#{sym}") elsif @tagset.nil? tag!(sym, *args, &block) else raise NoMethodError, "no such method `#{sym}'" end end
Create a tag named tag
. Other than the first argument which is
the tag name, the arguments are the same as the tags implemented via
method_missing.
# File lib/markaby/builder.rb, line 133 def tag!(tag, *args, &block) ele_id = nil if @auto_validation and @tagset if !@tagset.tagset.has_key?(tag) raise InvalidXhtmlError, "no element `#{tag}' for #{tagset.doctype}" elsif args.last.respond_to?(:to_hash) attrs = args.last.to_hash attrs.each do |k, v| atname = k.to_s.downcase.intern unless k =~ /:/ or @tagset.tagset[tag].include? atname raise InvalidXhtmlError, "no attribute `#{k}' on #{tag} elements" end if atname == :id ele_id = v.to_s if @elements.has_key? ele_id raise InvalidXhtmlError, "id `#{ele_id}' already used (id's must be unique)." end end end end end if block str = capture &block block = proc { text(str) } end f = fragment { @builder.method_missing(tag, *args, &block) } @elements[ele_id] = f if ele_id f end
Write a string
to the HTML stream without escaping it.
# File lib/markaby/builder.rb, line 104 def text(string) @builder << "#{string}" nil end
Returns a string containing the HTML stream. Internally, the stream is stored as an Array.
# File lib/markaby/builder.rb, line 99 def to_s @streams.last.to_s end
Builds an html tag with XHTML 1.0 Strict doctype instead.
# File lib/markaby/builder.rb, line 246 def xhtml_strict(&block) self.tagset = Markaby::XHTMLStrict xhtml_html &block end
Builds an html tag. An XML 1.0 instruction and an XHTML 1.0 Transitional
doctype are prepended. Also assumes :xmlns =>
"http://www.w3.org/1999/xhtml", :lang =>
"en"
.
# File lib/markaby/builder.rb, line 240 def xhtml_transitional(&block) self.tagset = Markaby::XHTMLTransitional xhtml_html &block end
# File lib/markaby/builder.rb, line 259 def fragment stream = @streams.last f1 = stream.length yield f2 = stream.length - f1 Fragment.new(stream, f1, f2) end
# File lib/markaby/builder.rb, line 253 def xhtml_html(&block) instruct! if @output_xml_instruction declare!(:DOCTYPE, :html, :PUBLIC, *tagset.doctype) tag!(:html, :xmlns => "http://www.w3.org/1999/xhtml", "xml:lang" => "en", :lang => "en", &block) end