[chronojump] Fix on possible crash on click encoder analyze with no curves selected

[Xavier de Blas <xaviblas src gnome org>]

commit a1d479cd1e4e98678f4f65fa517902736ee5a97e
Author: Xavier de Blas <xaviblas gmail com>
Date:   Fri Feb 27 19:04:40 2015 +0100

    Fix on possible crash on click encoder analyze with no curves selected

 src/gui/encoder.cs |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/src/gui/encoder.cs b/src/gui/encoder.cs
index 6db0085..f974d06 100644
--- a/src/gui/encoder.cs
+++ b/src/gui/encoder.cs
@@ -5471,6 +5471,13 @@ LogB.Debug("D");
                                encoderButtonsSensitive(encoderSensEnum.DONENOSIGNAL);
                        } else {
                                encoderButtonsSensitive(encoderSensEnumStored);
+
+                               //an user has one active concentric curve
+                               //signal of this curve is loaded
+                               //user change to ecc-con and recalculate
+                               //then that concentrinc curve disappears
+                               //button_encoder_analyze have to be unsensitive because there are no curves:
+                               button_encoder_analyze_sensitiveness();
                        }
                                
                        encoder_pulsebar_capture.Fraction = 1;