[WJG] (09/04/11) The Gtk+ Entry widget has a lots of interesting enhancements which have now been implemented within the Gnocl core code. 
The following script shows how to create embedded icons and progress bar functionality. Here's a snapshot! 

[https://lh5.googleusercontent.com/_yaFgKvuZ36o/TZeEZjc_SGI/AAAAAAAAA6g/ATBOdTnCMhY/s800/Screenshot-EntryIcons.png]

And the script itself:

======
#!/bin/sh
#\
exec tclsh "$0" "$@"

package require Gnocl

proc buttonRelease {w t p} {
        if {$p == "primary"} {
                $w configure -value "Gnocl Entry Widget"
        }
        if {$p == "secondary"} {
                $w configure -value ""
        }
}


set ent [gnocl::entry \
                -tooltip "HIDIHI" \
                -secondaryIconTooltip "Clear Entry Contents" \
                -hasFrame 0 \
                -primaryIcon "%#New" \
                -secondaryIcon "%#Clear" \
                -onIconPress {puts "PRESS %w %t %p"} \
                -onIconRelease { buttonRelease %w %t %p } \
                -onPreeditChanged {puts "preeditChanged %t"} \
                -secondaryIconSensitive 1 \
                -pulseStep 0.15]



gnocl::window -child $ent -title EntryIcons

        gnocl::update

if {1} {
set d 0.05
for {set i 0} {$i < 20} {incr i} {
        $ent progress [expr $i * $d]
        gnocl::update
        after 100
}

$ent progress 0.0
}


if {1} {
for {set i 0} {$i < 20} {incr i} {
        $ent pulse
        after 100
        gnocl::update
}
$ent progress 0.0
}
======



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