Buttons

Buttons are widgets that can be placed either in the title area or the caption area of a canvas. A click on a button invokes a function that can perform actions, including changing the text of the button or disabling it.

mybutton = button( bind=myaction, text='Click me!' )

Parameters:

• bind (function) – The function to be called when the button is clicked.

• text (string) – Text to appear on the button

• pos (attribute of canvas) – Location of button. Default is scene.caption_anchor.

• color (vector) – Color of button text. Modifiable.

• background (vector) – Color of button background. Modifiable.

• disabled (boolean) – If True, button is grayed out and does not respond.

• delete() – mybutton.delete() deletes the button.

A button that changes its own color and the color of a sphere:

ball = sphere(color=color.cyan)

def changecolor(evt):
        if evt.text == 'red':
                ball.color=color.red
                clrbtn.background = color.cyan
                clrbtn.text = 'cyan'
        else:
                ball.color=color.cyan
                clrbtn.text = 'red'
                clrbtn.background = color.red

clrbtn = button( bind=changecolor, text='red', background=color.red )

Button Event Attributes

The argument of the event handler function (‘evt’, in the code above) will have the following attributes (properties of the button at the time it was clicked):

• evt.text

• evt.color

• evt.background

• evt.disabled

Additionally, any attributes you have created for the widget (for example, name or id), will be available as attributes of evt.

See also

Event Handlers; Processing Events; Polling; Widget Position