Re: [ruby-gnome2-devel-en] Displaying web images

[Michael B. <be...@ju...>]

Hi,

I would like to download a series of images, and then the next one, not
individual images. That way I get a broader selection of images
(including older ones with the first download, newer ones later).

I am including my current code below. I tried loading a second set of
images after starting the auto_show, but the whole download is done
before the first image is shown.

Best
Michael


-snip-

require 'gtk3'
require 'open-uri'
require 'tempfile'
require 'flickraw'

class RubyApp < Gtk::Window
  
  def initialize
    super
    
    signal_connect "destroy" do 
      Gtk.main_quit end
      
    set_default_size 300, 200
    maximize
    set_window_position Gtk::Window::Position::CENTER 
    
    @pixbufs = []
    @flickpixbufs = []
    iswindow = true


    FlickRaw.api_key=
    FlickRaw.shared_secret=

    flickthread = Thread.new {
      flickresults = flickr.photos.search(:tags => "Tag", :per_page =>
50)

getimages(flickresults,"FlickRaw.url_b(currentresult)",@flickpixbufs)
    }

    # event handler
    signal_connect("key-press-event") do |_widget, event|
      case event.keyval
      when Gdk::Keyval::GDK_KEY_Right
        @pixbufs.push(@pixbufs.shift)
        update_image(@pixbufs.first)
      when Gdk::Keyval::GDK_KEY_Left
        @pixbufs.unshift(@pixbufs.pop)
        update_image(@pixbufs.first)
      when Gdk::Keyval::GDK_KEY_F11
        if iswindow
          fullscreen
          iswindow = false
        else
          unfullscreen
          iswindow = true
        end
      end
    end

    flickthread.join    
    @pixbufs = @flickpixbufs
    update_image(@pixbufs.first)

    auto_show(@pixbufs)
 
  end

  def getimages(resultarray, method, pixbufsarray)
    resultarray.each{|currentresult|        
      image_path = Tempfile.open("display-web-image-in-gtk") do |
tempfile|
        begin
          urlimage = open(eval(method))
        rescue OpenURI::HTTPError => e
          puts e
          puts "cannot load image"
          break
        end
        tempfile.write(urlimage.read)
        tempfile.path
      end
      unless image_path.nil?
        fillpixbufs(image_path,pixbufsarray)
      end
    }
  end

  def fillpixbufs(image,dlpixbufs)
    begin
      currentpixbuf = Gdk::Pixbuf.new(image)
    rescue IOError => e
      puts e
      puts "cannot load images"
      exit
    end
    maxheight = 700
    myheight = currentpixbuf.height
    if myheight > maxheight
      mywidth = currentpixbuf.width
      newwidth=(mywidth*(maxheight.to_f/myheight)).round

currentpixbuf=currentpixbuf.scale(newwidth,maxheight,Gdk::Pixbuf::INTERP_BILINEAR)
    end
    puts image
    dlpixbufs << currentpixbuf
  end

  def auto_show(pixbufs)    # auto mode
      GLib::Timeout.add(600) do
        @pixbufs.push(pixbufs.shift)
        update_image(pixbufs.first)
        true  # continue
      end
  end

  def update_image(currentpixbuf)
    if (defined?(@gtkimage)).nil?
      @gtkimage = Gtk::Image.new  :pixbuf => currentpixbuf
      add @gtkimage
    else
      @gtkimage.set_pixbuf(currentpixbuf)
    end
    show_all
  end
end


Gtk.init
  window = RubyApp.new
Gtk.main

-snip-

  
Am Sonntag, den 17.08.2014, 14:21 +0200 schrieb Detlef Reichl:
> Hi,
> 
> I don't know, whats your code look like, but I would do it in this way:
> 
> 
> Create a thread, that loads down the images. Every time, an image is
> completely loaded a flag is set by the loader. Then it waits, that the
> flag is unset.
> 
> The display system has a Fifo, where it cycles over with a timeout. In
> this timeout the loader flag is tested. If it is set, the image is
> pushed into the Fifo and the flag is unset after this.
> 
> Cheers, detlef
> 
> 
> 
> Am 17.08.2014 00:13, schrieb Michael Below:
> > Hi,
> > 
> > I am working on the web display issue again.
> > Now I would like to refresh the images. I.e.:
> > 
> > - get a set of 50 images
> > - display the first set, meanwhile get another set of 50 images
> > - as soon as the second set is downloaded, and the first set has been
> > shown at least once, switch from displaying first set to displaying
> > second set
> > - repeat infinitely
> > 
> > Thanks to your help, I have got the code to display the first set of
> > pictures in a loop like this:
> > 
> >  def auto_show(pixbufs)    # auto mode
> >       GLib::Timeout.add(600) do
> >         @pixbufs.push(pixbufs.shift)
> >         update_image(pixbufs.first)
> >         true  # continue
> >       end
> >   end
> > 
> > I guess I could add a second Timeout that switches the picture sets
> > every 5 minutes or so.  But is there a way to change the picture sets
> > after successfully loading the next one?
> > 
> > I successfully moved the download process into a separate thread, but I
> > can't get the download to run again and again while displaying images
> > and updating the buffer.
> >   
> > Cheers
> > Michael
> > 
> > 
> > Am Montag, den 26.05.2014, 08:46 +0200 schrieb Michael Below:
> >> Hi,
> >>
> >> Am Montag, den 26.05.2014, 12:30 +0900 schrieb Masafumi Yokoyama:
> >>
> >>> A GTK window is just shown when `Gtk.main` is called.
> >>> `show_all` sets flag to be displayed to all widgets, but doesn't
> >>> actually display until `Gtk.main` is called.
> >>
> >> Ah, I understand... I even tried to move Gtk.main into my #each loop,
> >> but this way it makes sense.
> >>  
> >>> It seems that need to design such as the following:
> >>
> >> Thanks, works fine.
> >>
> >> Cheers
> >>
> >> Michael
> > 
> > 
> > 
> > ------------------------------------------------------------------------------
> > _______________________________________________
> > ruby-gnome2-devel-en mailing list
> > rub...@li...
> > https://lists.sourceforge.net/lists/listinfo/ruby-gnome2-devel-en
> > 
> 
> 
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