Script Examples: Script Examples Overview » screenshots.lym

Using the HTML browser dialog II: a screenshot gallery

This example employs the HTML browser dialog to implement a simple screenshot gallery: by clicking on the "Add screenshot" item in the toolbar, a screenshot is taken and placed in the HTML browser window. Each screenshot will be represented by a thumbnail image and a screen-size image. The browser will display the thumbnails together with a link that will put the viewer to the original location. By clicking on the thumbnail image, the enlarged version is shown in the browser window.

Source code

module Examples
 
  class Screenshot
  
    def initialize( index, view )
  
      @index = index
      @small_file = "screenshot.small.#{@index}.png"
      @large_file = "screenshot.large.#{@index}.png"
  
      view.save_image( @small_file, 80, 60 )
      view.save_image( @large_file, 800, 600 )
      @box = view.box
  
    end
  
    def box
      return @box
    end
  
    def html_snippet
      s = ""
      l = sprintf( "%.3f", @box.left.to_s )
      r = sprintf( "%.3f", @box.right.to_s )
      b = sprintf( "%.3f", @box.bottom.to_s )
      t = sprintf( "%.3f", @box.top.to_s )
      s += "<a style=\"font-size:10px\" href=\"int:navigate?#{@index}\">#{l},#{b} <br/>"
      s += "#{r},#{t}</a><br/>"
      s += "<a href=\"int:enlarged?#{@large_file}\"><img src=\"file:#{@small_file}\" width=\"80\" height=\"60\"/></a>"
      return s
    end
  
  end
  
  class ScreenshotBrowser < RBA::BrowserDialog
  
    def initialize
      @browser_source = ScreenshotServer.new
      self.set_source( @browser_source )
      self.set_home( "int:index" )
      self.show
    end
  
    def add
      @browser_source.add
      self.show
      self.load( "int:index" )
      self.reload 
    end
  
  end
  
  class ScreenshotServer < RBA::BrowserSource
  
    def initialize
      @screenshots = []
    end
  
    def add
      view = RBA::Application::instance.main_window.current_view
      if view != nil
        @screenshots.push( Screenshot.new( @screenshots.size, view ) )
      end
    end
  
    def get( url )
      url = url.sub( /^int:/, "" )
      if url == "index"
        return self.index
      elsif url =~ /^enlarged\?(.*)/
        return enlarged( $1 )
      elsif url =~ /^navigate\?(.*)/
        navigate( $1.to_i )
      end
      return ""
    end
  
    def navigate( index )
      view = RBA::Application::instance.main_window.current_view
      if view != nil
        view.zoom_box( @screenshots[index].box )
      end
    end
  
    def enlarged( img )
      return "<a href=\"int:index\">Index Page</a><br/><img src=\"file:#{img}\"/>"
    end
  
    def index
      r = []
      r.push( "<html><h1>Screenshot gallery</h1><p><p>" )
      r.push( "<table>" )
      r.push( "<tr>" )
      n = 0
      @screenshots.each { |s|
        r.push( "<td>" )
        r.push( s.html_snippet )
        r.push( "</td>" )
        n += 1
        if n % 5 == 0
          r.push( "</tr><tr>" )
        end
      }
      r.push( "</tr>" )
      r.push( "</table>" )
      return r.join( "" )
    end
  
  end
  
  # ------------------------------------------------------------------
  #  Declare and register the menu items 
  
  app = RBA::Application::instance
  mw = app.main_window
  menu = mw.menu
  
  @screenshot_browser = nil
  
  @add_screenshot_action = RBA::Action::new
  @add_screenshot_action.title = "Add Screenshot"
  @add_screenshot_action.on_triggered do
    @screenshot_browser ||= ScreenshotBrowser.new 
    @screenshot_browser.add
  end
  
  @show_gallery_action = RBA::Action::new
  @show_gallery_action.title = "Show Gallery"
  @show_gallery_action.on_triggered do
    @screenshot_browser && @screenshot_browser.show
  end
  
  menu.insert_separator( "@toolbar.end", "tb_sep" )
  menu.insert_item( "@toolbar.end", "add_screenshot", @add_screenshot_action )
  menu.insert_item( "@toolbar.end", "show_gallery", @show_gallery_action )

end