class Gtk::CellRenderer

• Gtk::CellRenderer
• GObject::InitiallyUnowned
• GObject::Object
• Reference
• Object

Overview

An object for rendering a single cell

The Gtk::CellRenderer is a base class of a set of objects used for rendering a cell to a cairo_::t. These objects are used primarily by the Gtk::TreeView widget, though they aren’t tied to them in any specific way. It is worth noting that Gtk::CellRenderer is not a Gtk::Widget and cannot be treated as such.

The primary use of a Gtk::CellRenderer is for drawing a certain graphical elements on a cairo_::t. Typically, one cell renderer is used to draw many cells on the screen. To this extent, it isn’t expected that a CellRenderer keep any permanent state around. Instead, any state is set just prior to use using GObjects property system. Then, the cell is measured using gtk_cell_renderer_get_preferred_size(). Finally, the cell is rendered in the correct location using gtk_cell_renderer_snapshot().

There are a number of rules that must be followed when writing a new Gtk::CellRenderer. First and foremost, it’s important that a certain set of properties will always yield a cell renderer of the same size, barring a style change. The Gtk::CellRenderer also has a number of generic properties that are expected to be honored by all children.

Beyond merely rendering a cell, cell renderers can optionally provide active user interface elements. A cell renderer can be “activatable” like Gtk::CellRendererToggle, which toggles when it gets activated by a mouse click, or it can be “editable” like Gtk::CellRendererText, which allows the user to edit the text using a widget implementing the Gtk::CellEditable interface, e.g. Gtk::Entry. To make a cell renderer activatable or editable, you have to implement the Gtk::CellRendererClass.activate or Gtk::CellRendererClass.start_editing virtual functions, respectively.

Many properties of Gtk::CellRenderer and its subclasses have a corresponding “set” property, e.g. “cell-background-set” corresponds to “cell-background”. These “set” properties reflect whether a property has been set or not. You should not set them independently.

Direct Known Subclasses

• Gtk::CellRendererPixbuf
• Gtk::CellRendererProgress
• Gtk::CellRendererSpinner
• Gtk::CellRendererText
• Gtk::CellRendererToggle

Defined in:

Constructors

• .new

  Initialize a new CellRenderer.

• .new(*, cell_background : String | Nil = nil, cell_background_rgba : Gdk::RGBA | Nil = nil, cell_background_set : Bool | Nil = nil, editing : Bool | Nil = nil, height : Int32 | Nil = nil, is_expanded : Bool | Nil = nil, is_expander : Bool | Nil = nil, mode : Gtk::CellRendererMode | Nil = nil, sensitive : Bool | Nil = nil, visible : Bool | Nil = nil, width : Int32 | Nil = nil, xalign : Float32 | Nil = nil, xpad : UInt32 | Nil = nil, yalign : Float32 | Nil = nil, ypad : UInt32 | Nil = nil)

Class Method Summary

• .g_type : UInt64

  Returns the type id (GType) registered in GLib type system.

Instance Method Summary

• #==(other : self)

  Returns true if this reference is the same as other.

• #activate(event : Gdk::Event, widget : Gtk::Widget, path : String, background_area : Gdk::Rectangle, cell_area : Gdk::Rectangle, flags : Gtk::CellRendererState) : Bool

  Passes an activate event to the cell renderer for possible processing.

• #aligned_area(widget : Gtk::Widget, flags : Gtk::CellRendererState, cell_area : Gdk::Rectangle) : Gdk::Rectangle

  Gets the aligned area used by cell inside cell_area.

• #alignment : Nil

  Fills in xalign and yalign with the appropriate values of cell.

• #cell_background=(value : String) : String
• #cell_background=(value : Nil) : Nil

  Set #cell_background property to nil.

• #cell_background_rgba : Gdk::RGBA | Nil
• #cell_background_rgba=(value : Gdk::RGBA | Nil) : Gdk::RGBA | Nil
• #cell_background_set=(value : Bool) : Bool
• #cell_background_set? : Bool
• #editing? : Bool
• #editing_canceled_signal
• #editing_started_signal
• #fixed_size : Nil

  Fills in width and height with the appropriate size of cell.

• #hash(hasher)

  See Object#hash(hasher)

• #height : Int32
• #height=(value : Int32) : Int32
• #is_activatable : Bool

  Checks whether the cell renderer can do something when activated.

• #is_expanded : Bool

  Checks whether the given Gtk::CellRenderer is expanded.

• #is_expanded=(is_expanded : Bool) : Nil

  Sets whether the given Gtk::CellRenderer is expanded.

• #is_expanded? : Bool
• #is_expander : Bool

  Checks whether the given Gtk::CellRenderer is an expander.

• #is_expander=(is_expander : Bool) : Nil

  Sets whether the given Gtk::CellRenderer is an expander.

• #is_expander? : Bool
• #mode : Gtk::CellRendererMode
• #mode=(value : Gtk::CellRendererMode) : Gtk::CellRendererMode
• #padding : Nil

  Fills in xpad and ypad with the appropriate values of cell.

• #preferred_height(widget : Gtk::Widget) : Nil

  Retrieves a renderer’s natural size when rendered to widget.

• #preferred_height_for_width(widget : Gtk::Widget, width : Int32) : Nil

  Retrieves a cell renderers’s minimum and natural height if it were rendered to widget with the specified width.

• #preferred_size(widget : Gtk::Widget) : Gtk::Requisition

  Retrieves the minimum and natural size of a cell taking into account the widget’s preference for height-for-width management.

• #preferred_width(widget : Gtk::Widget) : Nil

  Retrieves a renderer’s natural size when rendered to widget.

• #preferred_width_for_height(widget : Gtk::Widget, height : Int32) : Nil

  Retrieves a cell renderers’s minimum and natural width if it were rendered to widget with the specified height.

• #request_mode : Gtk::SizeRequestMode

  Gets whether the cell renderer prefers a height-for-width layout or a width-for-height layout.

• #sensitive : Bool

  Returns the cell renderer’s sensitivity.

• #sensitive=(sensitive : Bool) : Nil

  Sets the cell renderer’s sensitivity.

• #sensitive? : Bool
• #set_alignment(xalign : Float32, yalign : Float32) : Nil

  Sets the renderer’s alignment within its available space.

• #set_fixed_size(width : Int32, height : Int32) : Nil

  Sets the renderer size to be explicit, independent of the properties set.

• #set_padding(xpad : Int32, ypad : Int32) : Nil

  Sets the renderer’s padding.

• #snapshot(snapshot : Gtk::Snapshot, widget : Gtk::Widget, background_area : Gdk::Rectangle, cell_area : Gdk::Rectangle, flags : Gtk::CellRendererState) : Nil

  Invokes the virtual render function of the Gtk::CellRenderer.

• #start_editing(event : Gdk::Event | Nil, widget : Gtk::Widget, path : String, background_area : Gdk::Rectangle, cell_area : Gdk::Rectangle, flags : Gtk::CellRendererState) : Gtk::CellEditable | Nil

  Starts editing the contents of this cell, through a new Gtk::CellEditable widget created by the Gtk::CellRendererClass.start_editing virtual function.

• #state(widget : Gtk::Widget | Nil, cell_state : Gtk::CellRendererState) : Gtk::StateFlags

  Translates the cell renderer state to Gtk::StateFlags, based on the cell renderer and widget sensitivity, and the given Gtk::CellRendererState.

• #stop_editing(canceled : Bool) : Nil

  Informs the cell renderer that the editing is stopped.

• #visible : Bool

  Returns the cell renderer’s visibility.

• #visible=(visible : Bool) : Nil

  Sets the cell renderer’s visibility.

• #visible? : Bool
• #width : Int32
• #width=(value : Int32) : Int32
• #xalign : Float32
• #xalign=(value : Float32) : Float32
• #xpad : UInt32
• #xpad=(value : UInt32) : UInt32
• #yalign : Float32
• #yalign=(value : Float32) : Float32
• #ypad : UInt32
• #ypad=(value : UInt32) : UInt32

Constructor Detail

Class Method Detail

Instance Method Detail