added the condition property for buttons

README.md

@@ -10,7 +10,7 @@ The `global` section can be used to define general styling. this includes:
 
 `background`: hex color
 `foreground`: hex color
-`highlight`: hex color (color on hover)
+`highlight`: hex color, color on hover
 `padding_x`: integer
 `padding_y`: integer
 
@@ -36,6 +36,7 @@ All components have the following properties:
 Buttons are defined in a section that starts with `button:`, and perform an action when clicked. They're also highlighted on hover. They have the following extra properties:
 
 `command`: the shell command to run on click
+`condition`: an evaluated expression that returns "true" if the button should be enabled.
 
 #### Label
 

sysmenu.py

@@ -94,6 +94,10 @@ def make_button(name: str):
 	)
 	if 'font' in spec:
 		button.configure(font = font(spec['font']))
+	if 'condition' in spec:
+		state = beval(spec['condition']);
+		if state.lower() != "true":
+			button['state'] = 'disabled'
 	components.append(button)
 
 def make_label(name: str):