1 files changed, 15 insertions, 4 deletions
diff --git a/tktest.py b/tktest.py
index d8f759c..8f9bf1e 100755
--- a/tktest.py
+++ b/tktest.py
@@ -4,16 +4,22 @@
 
 import threading
 import time
-from tkinter import Tk, N, E, S, W, Label
+from tkinter import Tk, N, E, S, W, Label, Button
 import sys
 
 from blc.workspace import Workspace
 from blc.tk import TkOutput
 from blc.render import BasicRenderer
 
-def update_time(m, l, r):
+def update(m, l, sl, r):
+    """Update GUI elements."""
+    if r.stall_lock.acquire(blocking=False):
+        r.stall_lock.release()
+        sl.config(text="Running")
+    else:
+        sl.config(text="Stalled")
     l.config(text="%.1f" % ((time.monotonic() - r.start_time) if r.start_time is not None else 0))
-    m.after(50, lambda: update_time(m,l,r))
+    m.after(50, lambda: update(m,l,sl,r))
 
 if len(sys.argv) != 3:
     print("Usage: %s <workspace> <show id>" % sys.argv[0])
@@ -32,12 +38,17 @@ output.grid(row=0, sticky=N+E+S+W)
 label = Label(root)
 label.grid(row=1,sticky=N+E+S+W)
 
+slabel = Label(root)
+slabel.grid(row=2,sticky=N+E+S+W)
+
 root.wm_title("BLC+ TkTest - "+s.name)
 
 renderer = BasicRenderer(s, output, minnx=13)
 rthread = threading.Thread(target=renderer.start)
 rthread.start()
 
-root.after(50, lambda: update_time(root, label, renderer))
+Button(root,text="Advance",command=lambda *args: renderer.advance()).grid(row=3, sticky=N+E+S+W)
+
+root.after(50, lambda: update(root, label, slabel, renderer))
 
 root.mainloop()