[Vala] Compilation errors

[Satyajit Sahoo <satyajit happy gmail com>]

Hi. I'm trying to make a small GUI with vala and GTK3. But I get error when
compiling. I'll be grateful if someone could fix it. I'm really a noob in
vala and this is probably my first program.

The code is here - https://github.com/satya164/gtk-theme-config

I get this error,

valac --pkg gtk+-3.0 gtk-theme-config.vala -o gtk-theme-config
gtk-theme-config.vala:131.12-131.40: error: invocation of void method
not allowed as expression
                color =  this.color_button.get_rgba ();
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Compilation failed: 1 error(s), 0 warning(s)
make: *** [gtk-theme-config] Error 1



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Satyajit Sahoo
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