10.2. Arrows

The Arrow widget draws an arrowhead, facing in a number of possible directions and having a number of possible styles. It can be useful when placed on a button in many applications. Like the Label widget, it emits no signals.

There are only a few methods for manipulating an Arrow widget:

Gtk::Arrow.new( arrow_type, shadow_type )
Gtk::Arrow#set( arrow_type, shadow_type )

# Retrieves arrow_type, returns int 0-3
# 0 = Up
# 1 = Down
# 2 = Left
# 3 = Right
Gtk::Arrow#arrow_type

# Just syntax sugar, they both do the same thing
Gtk::Arrow#arrow_type=( arrow_type )
Gtk::Arrow#set_arrow_type( arrow_type )

# Retrieves arrow_type, returns int 1-4
# 1 = SHADOW_IN
# 2 = SHADOW_OUT
# 3 = SHADOW_ETCHED_IN
# 4 = SHADOW_ETCHED_OUT
Gtk::Arrow#shadow_type

# Just syntax sugar, they both do the same thing
Gtk::Arrow#set_shadow_type( shadow_type )
Gtk::Arrow#shadow_type=( shadow_type )

The first creates a new arrow widget with the indicated type and appearance. The second allows these values to be altered retrospectively. The next method will retrieve the arrow_type, and return an int value between 0 and 3. The next two methods will set the arrow_type retrospectively. The next method, Gtk::Arrow#shadow_type will retrieve the shadow type used on the arrow. It will also return an int value between 1 and 4. The last two methods allow you to set shadow_type retrospectively. The arrow_type argument may take one of the following values:

Gtk::Arrow::UP or 0
Gtk::Arrow::DOWN or 1
Gtk::Arrow::LEFT or 2
Gtk::Arrow::RIGHT or 3

These values obviously indicate the direction in which the arrow will point. You may also pass an int between 0 and 3. The shadow_type argument may take one of these values:

Gtk::SHADOW_IN or 1
Gtk::SHADOW_OUT or 2 (the default)
Gtk::SHADOW_ETCHED_IN or 3
Gtk::SHADOW_ETCHED_OUT or 4

Here is a brief example to illustrate their use:

require 'gtk2'

# Create an Arrow widget with the specified parameters
# and pack it into a button
def create_arrow_button( arrow_type, shadow_type )

   button = Gtk::Button.new
   arrow = Gtk::Arrow.new( arrow_type, shadow_type )
   
   button.add( arrow )

   button.show
   arrow.show
   
   return button
end

# Initialize the toolkit
Gtk.init

# Create a new window and set the title
window =Gtk::Window.new( Gtk::Window::TOPLEVEL )
window.title=( "Arrow Buttons" )

# It's a good idea to do this for all windows
window.signal_connect( "destroy" ) { Gtk.main_quit }

# Sets the border width of the window
window.border_width=( 10 )

# Create a box to hold the arrows/buttons
box = Gtk::HBox.new( false, 0 )
box.border_width=( 2 )
window.add( box )

# Pack and show all our widgets
box.show

button = create_arrow_button( Gtk::Arrow::UP, Gtk::SHADOW_IN )
box.pack_start( button, false, false, 3 )

button = create_arrow_button( Gtk::Arrow::DOWN, Gtk::SHADOW_OUT )
box.pack_start( button, false, false, 3 )

# Showing how we can pass integers for the arrow types
button = create_arrow_button( 2, Gtk::SHADOW_ETCHED_IN )
box.pack_start( button, false, false, 3 )

# Showing how we can pass integers for the shadow types
button = create_arrow_button( Gtk::Arrow::RIGHT, 4 )
box.pack_start( button, false, false, 3 )

window.show

Gtk.main