showProgress handles reentrant calls by completing these calls non-interactively.

src/mcedit2/util/showprogress.py

@@ -8,6 +8,7 @@ from PySide.QtCore import Qt
 import time
 import itertools
 from mcedit2.util.worldloader import LoaderTimer
+from mceditlib.util import exhaust
 from mceditlib.util.progress import rescaleProgress
 
 log = logging.getLogger(__name__)
@@ -32,6 +33,8 @@ class MCEProgressDialog(QtGui.QProgressDialog):
         event.ignore()
 
 
+_progressBarActive = False
+
 def showProgress(text, *tasks, **kwargs):
     """
     Show a progress dialog for the given task(s). Each task should be an iterable,
@@ -47,10 +50,18 @@ def showProgress(text, *tasks, **kwargs):
     :return:
     :rtype:
     """
+    global _progressBarActive
+
+    if _progressBarActive:
+        for task in tasks:
+            exhaust(task)
+        return
+
     progress = None
     cancel = kwargs.pop('cancel', None)
     start = time.time()
     shown = False
+    try:
         with LoaderTimer.stopCtx():
 
             dialog = MCEProgressDialog(QtGui.qApp.mainWindow)
@@ -97,4 +108,6 @@ def showProgress(text, *tasks, **kwargs):
 
             dialog.reset()
             return progress
+    finally:
+        _progressBarActive = False