Volume thresholding: fixed visual bug that would delay the update of the threshold in the bar

Signed-off-by: Nicola Vigano <nicola.vigano@esrf.fr>

5_reconstruction/GtGuiThresholdGrain.m

@@ -180,8 +180,8 @@ classdef GtGuiThresholdGrain < GtVolView
 
         function movedSlider(obj)
             new_thresh = get(obj.conf.h_thr_slider, 'Value');
-            set(obj.conf.h_thr_edit, 'String', num2str(obj.threshold));
             obj.setThreshold(new_thresh);
+            set(obj.conf.h_thr_edit, 'String', num2str(new_thresh));
             obj.updateDisplay();
         end