[Gtk2hs-commit] (main branch): Add function for implementing size requisition and allocation in widgets.

[Axel S. <si...@co...>]

Sat Nov  1 09:29:43 EDT 2008  Axe...@en...
  * Add function for implementing size requisition and allocation in widgets.

    hunk ./gtk/Graphics/UI/Gtk/Abstract/Widget.chs.pp 89
    +  widgetQueueResize,
    +#if GTK_CHECK_VERSION(2,4,0)
    +  widgetQueueResizeNoRedraw,
    +#endif
    +  widgetSizeRequest,
    +  widgetGetChildRequisition,
    +  widgetSizeAllocate,
    hunk ./gtk/Graphics/UI/Gtk/Abstract/Widget.chs.pp 487
    --- * Functions to be used with 'Graphics.UI.Gtk.Misc.DrawingArea'.
    +-- * Functions to be used with 'Graphics.UI.Gtk.Misc.DrawingArea' or
    +--   container implementations.
    hunk ./gtk/Graphics/UI/Gtk/Abstract/Widget.chs.pp 498
    +-- | This function is only for use in widget implementations. Flags a widget
    +-- to have its size renegotiated; should be called when a widget for some
    +-- reason has a new size request. For example, when you change the text in a
    +-- 'Graphics.UI.Gtk.Display.Label.Label',
    +-- 'Graphics.UI.Gtk.Display.Label.Label' queues a resize to ensure there's
    +-- enough space for the new text.
    +--
    +widgetQueueResize :: WidgetClass self => self -> IO ()
    +widgetQueueResize self =
    +  {# call widget_queue_resize #}
    +    (toWidget self)
    +
    +#if GTK_CHECK_VERSION(2,4,0)
    +-- | This function works like 'widgetQueueResize', except that the widget is
    +-- not invalidated.
    +--
    +-- * Available since Gtk+ version 2.4
    +--
    +widgetQueueResizeNoRedraw :: WidgetClass self => self -> IO ()
    +widgetQueueResizeNoRedraw self =
    +  {# call widget_queue_resize_no_redraw #}
    +    (toWidget self)
    +#endif
    +
    +-- | This function is typically used when implementing a
    +-- 'Graphics.UI.Gtk.Abstract.Container.Container' subclass. Obtains the preferred size
    +-- of a widget. The container uses this information to arrange its child
    +-- widgets and decide what size allocations to give them with
    +-- 'widgetSizeAllocate'.
    +--
    +-- You can also call this function from an application, with some caveats.
    +-- Most notably, getting a size request requires the widget to be associated
    +-- with a screen, because font information may be needed. Multihead-aware
    +-- applications should keep this in mind.
    +--
    +-- Also remember that the size request is not necessarily the size a widget
    +-- will actually be allocated.
    +--
    +widgetSizeRequest :: WidgetClass self => self -> IO Requisition
    +widgetSizeRequest self = alloca $ \reqPtr -> do
    +  {#call widget_size_request #} (toWidget self) (castPtr reqPtr)
    +  peek reqPtr
    +
    +-- | This function is only for use in widget implementations. Obtains the
    +-- chached requisition information in the widget, unless someone has forced a
    +-- particular geometry on the widget (e.g. with 'widgetSetUsize'), in which
    +-- case it returns that geometry instead of the widget's requisition.
    +--
    +-- This function differs from 'widgetSizeRequest' in that it retrieves the
    +-- last size request value stored in the widget, while 'widgetSizeRequest'
    +-- actually emits the 'sizeRequest' signal on the widget to compute the size
    +-- request (which updates the widget's requisition information).
    +--
    +-- Since this function does not emit the 'sizeRequest' signal, it can only be
    +-- used when you know that the widget's requisition is up-to-date, that is,
    +-- 'widgetSizeRequest' has been called since the last time a resize was
    +-- queued. In general, only container implementations have this information;
    +-- applications should use 'widgetSizeRequest'.
    +--
    +widgetGetChildRequisition :: WidgetClass self => self -> IO Requisition
    +widgetGetChildRequisition self = alloca $ \reqPtr -> do
    +  {#call widget_get_child_requisition #} (toWidget self) (castPtr reqPtr)
    +  peek reqPtr
    +
    +-- | This function is only used by
    +-- 'Graphics.UI.Gtk.Abstract.Container.Container' subclasses, to assign a
    +-- size and position to their child widgets.
    +--
    +widgetSizeAllocate :: WidgetClass self => self
    +  -> Allocation -- ^ The @x@ and @y@ values of the rectangle determine the
    +                --   the position of the widget's area relative to its parent
    +                --   allocation.
    +  -> IO ()
    +widgetSizeAllocate self rect = with rect $ \rectPtr ->
    +  {#call widget_size_allocate#} (toWidget self) (castPtr rectPtr)
    +
    hunk ./gtk/Graphics/UI/Gtk/General/Structs.hsc 411
    --- * for Widget's size_allocate signal
    +-- * For Widget's 'Graphics.UI.Gtk.Abstract.Widget.sizeAllocate' signal.
    +--   The @x@ and @y@ values of the rectangle refer to the widgets position
    +--   relative to its parent window.
    hunk ./gtk/Graphics/UI/Gtk/General/Structs.hsc 420
    --- * for Widget's size_request
    +-- * For 'Graphics.UI.Gtk.Abstract.Widget.widgetSizeRequest'. The values
    +--   represent the desired width and height of the widget.