I need to get an URL into the file_picker_callback function, so that the image dialog opens my php form instead of the basic image dialog

The problem is that it opens my Windows Explorer over the image dialog. I can close it and then I can see my own form but how to avoid the Explorer opening ?

The second problem (solved - see below) is that I need to add an id at the end of my URL. So I need to get it through a variable linked to the original form (the one where I want to integrate the image).

Finally, I solved the second problem of the id this way :

file_picker_callback: function (cb, value, meta) {
   var post_id = document.getElementById('inputid').getAttribute('value');
   var myUrl = "http://localhost/www/Tuto/pilote/medias/index/" + post_id;
   tinymce.activeEditor.windowManager.openUrl({    
        title: 'Gallerie',
        url: myUrl,
        width: 500,
        height: 400,
        resizable: 'yes',
        inline: 'no',
        close_previous: 'no'
   });

[...]

I still need help to prevent the Windows Explorer to open before my image dialog.