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-rw-r--r--lib/wx/examples/demo/ex_canvas.erl13
1 files changed, 8 insertions, 5 deletions
diff --git a/lib/wx/examples/demo/ex_canvas.erl b/lib/wx/examples/demo/ex_canvas.erl
index 2a95ea0777..b00ce81993 100644
--- a/lib/wx/examples/demo/ex_canvas.erl
+++ b/lib/wx/examples/demo/ex_canvas.erl
@@ -136,11 +136,14 @@ handle_event(#wx{event = #wxCommand{type = command_button_clicked}},
{noreply, State};
handle_event(#wx{event = #wxSize{size={W,H}}},
State = #state{bitmap=Prev, canvas=Canvas}) ->
- Bitmap = wxBitmap:new(W,H),
- draw(Canvas, Bitmap, fun(DC) -> wxDC:clear(DC) end),
- wxBitmap:destroy(Prev),
- {noreply, State#state{bitmap = Bitmap}};
-
+ if W > 0 andalso H > 0 ->
+ Bitmap = wxBitmap:new(W,H),
+ draw(Canvas, Bitmap, fun(DC) -> wxDC:clear(DC) end),
+ wxBitmap:destroy(Prev),
+ {noreply, State#state{bitmap = Bitmap}};
+ true ->
+ {noreply, State}
+ end;
handle_event(#wx{event = #wxMouse{type=left_down, x=X, y=Y}}, State) ->
{noreply, State#state{pos={X,Y}}};
handle_event(#wx{event = #wxMouse{type=motion, x=X1, y=Y1}},