Issue with Talend in Ubuntu 15.05 KDE - Assertion `!_button._widget' failed.

While working with Talend, some dialogues freezes and then Talend crashes.

In the console  you will observe an error

java: /build/buildd/gtk2-engines-oxygen-1.4.5/src/animations/oxygencomboboxdata.cpp:87: void Oxygen::ComboBoxData::setButton(GtkWidget*): Assertion `!_button._widget' failed.

A detailed bug discussion is available here 

Two solutions are given to solve this

1. To change appearence - Click here to see 
2. To tweak little code - Click here to see

Solution # 2 worked for me and a brief is here.

Edit the file "/usr/share/themes/oxygen-gtk/gtk-2.0/gtkrc" 

and change 

GtkComboBox::appears-as-list = 1 

TO

GtkComboBox::appears-as-list = 0