NAME

Term::Fabulous::Event::CanvasResize - A canvas got a new size

SYNOPSIS

$canvas->on( CanvasResize => sub ($event) {
	$canvas->clear;
	$canvas->put_text( 0, 0, sprintf( '%d x %d cells', $event->columns, $event->rows ) );
	return;
} );

DESCRIPTION

A Term::Fabulous::Widget::Canvas (and every widget built on it, such as Term::Fabulous::Widget::PixelCanvas, the charts and the input widgets) fires CanvasResize on itself when the layout gives its content box a new size. The canvas buffer has already been resized when the event fires, and the frame that shows the new size is painted right after the listeners return, so a listener is the right place to draw content that depends on the size.

A CanvasResize event bubbles like other events (its bubble mode is IF_CONTINUE): a listener on an ancestor, for example on the root, also sees the resizes of every canvas, pixel canvas and input widget below it, as long as the listeners on the way return Clay::UI::Enum::Result->CONTINUE (the built-in widgets add no CanvasResize listeners of their own, so they pass it on). Check $event->target in such a listener:

$root->on( CanvasResize => sub ($event) {
	return Clay::UI::Enum::Result->CONTINUE unless $event->target == $chart;
	redraw_chart();
	return;
} );

The first event comes with the first frame that lays the canvas out: before that, the buffer has 0 x 0 cells. Cells that still fit keep their content; see "Buffer size" in Term::Fabulous::Widget::Canvas.

The class is a subclass of Clay::UI::Events::Event, so target, current_target, name ('CanvasResize' unless given to the constructor) and bubble_mode (IF_CONTINUE) are available as well.

CONSTRUCTOR

new

my $event = Term::Fabulous::Event::CanvasResize->new( columns => 40, rows => 10 );

Built by the canvas itself; there is rarely a reason to build one. Both parameters below are required, and unknown parameters die. The name and bubble_mode parameters of Clay::UI::Events::Event are accepted as well.

columns

The new width of the canvas buffer in columns.

rows

The new height of the canvas buffer in rows.

METHODS

columns

my $width = $event->columns;

The new width of the canvas buffer in columns (the same as $canvas->columns).

rows

my $height = $event->rows;

The new height of the canvas buffer in rows (the same as $canvas->rows).

SEE ALSO

Term::Fabulous::Widget::Canvas, Term::Fabulous::Widget::PixelCanvas, "CANVASES" in Term::Fabulous::Manual::Charts, "Plot data on a pixel canvas (PixelCanvas)" in Term::Fabulous::Cookbook::Canvases.