Combo

(Contains a tkinter.OptionMenu object)

__init__(self, master, options=[], selected=None, command=None, grid=None, align=None, visible=True, enabled=None)

What is it?

The Combo object displays a drop down box allowing a single option to be selected from a list of options.

How do I make one?

Create a Combo object like this:

from guizero import App, Combo
app = App()
combo = Combo(app, options=["Beef", "Chicken", "Fish", "Vegetarian"])
app.display()

Starting parameters

When you create a Combo object you must specify a master and you can specify any of the optional parameters. Specify parameters in the brackets, like this: combo = Combo(app, options=["Beef", "Chicken", "Fish", "Vegetarian"])

Parameter	Takes	Default	Compulsory	Description
master	App, Window or Box	-	Yes	The container to which this widget belongs
options	List	[]	No	A list of options to display
selected	string	None	No	The option to select by default
align	string	None	-	Alignment of this widget within its container. Possible values: "top", "bottom", "left", "right".
command	function name	None	-	The name of a function to call when a different option is selected. This function MUST take either zero or one argument, if the function takes one argument the current value of the Combo will be given.
grid	List [int, int]	None	-	[x,y] coordinates of this widget. This parameter is only required if the master object has a grid layout.
visible	boolean	True	No	If the widget should be visible.
enabled	boolean	None	No	If the widget should be enabled. If None (the default) the enabled property will be inherited from the master
width	size	None	No	Set the width of the widget in characters or to "fill"
height	size	None	No	Set the height of the widget in characters or to "fill"

Methods

You can call the following methods on a Combo object.

Method	Takes	Returns	Description
append(option)	item (string)	-	Appends a new option to the end of the Combo.
after(time, command, args=None)	time (int), command (function name), args (list of arguments)	-	Schedules a single call to command after time milliseconds. (To repeatedly call the same command, use repeat())
cancel(command)	command (function name)	-	Cancels a scheduled call to command
clear()	-	-	Removes all options from the Combo box
destroy()	-	-	Destroys the widget
disable()	-	-	Disables the widget so that it is "greyed out" and cannot be interacted with
enable()	-	-	Enables the widget
focus()	-	-	Gives focus to the widget
hide()	-	-	Hides the widget from view. This method will unpack the widget from the layout manager.
insert(index, option)	index (int), item (string)	-	Insert a new option in the Combo at index
remove(option)	item (string)	Boolean	Removes the first option from the Combo. Returns True if an item was removed.
repeat(time, command, args=None)	time (int), command (function name), args (list of arguments)	-	Repeats command every time milliseconds. This is useful for scheduling a function to be regularly called, for example updating a value read from a sensor.
resize(width, height)	width (int), height (int)	-	Sets the width and height of the widget
select_default()	-	-	Resets the combo box so that the first item is selected
show()	-	-	Displays the widget if it was previously hidden
update_command(command)	command (function name)	-	Updates the function to call when a different option is selected.
add_option(option)	option (string)	-	Adds a new item to the combo box with the value option
get()	-	string	Replaced by the value property
set(text)	text (string)	-	Replaced by the value property

Methods in italics will still work but are deprecated - this means you should stop using them because they may not work in future versions of guizero

Properties

You can set and get the following properties:

Method	Data type	Description
align	string	The alignment of this widget within its container
bg	color	The background colour of the widget
enabled	boolean	True if the widget is enabled
font	string	The font of the text
grid	List	[x,y] coordinates of this widget. This parameter is only required if the master object has a grid
height	size	Set the height of the widget in characters or to "fill"
master	App or Box	The container to which this widget belongs
value	string	The text associated with the currently selected option
visible	boolean	If this widget is visible
width	size	Set the width of the widget in characters or to "fill"
text_size	int	The size of the text
text_color	color	The colour of the text

Refer to a property as <name of widget>.property. For example, if your Combo object is called combo you would write combo.value.

You can set the property (for example combo.value = "Chicken") or get the value of the property to use (for example print(combo.value)).

Examples

Calling a function when the value selected changes

You can call a function when the selected value in a Combo object changes. The function you call can take either zero or one argument, if the function takes one argument it will automatically be passed a string containing the currently selected value from the Combo object.

from guizero import App, Text, Combo
def you_chose(selected_value):
    if selected_value == "Tiny goblet":
        result.value = "You chose...wisely"
    else:
        result.value = "You chose...poorly"

app = App()
instructions = Text(app, text="Choose a goblet")
combo = Combo(app, options=["", "Huge golden goblet", "Jewel encrusted goblet", "Tiny goblet"], command=you_chose)
result = Text(app)
app.display()