<ThreadSafetyStatement>Gtk# is thread aware, but not thread safe; See the <linklocation="node:gtk-sharp/programming/threads">Gtk# Thread Programming</link> for details.</ThreadSafetyStatement>
<summary>GtkWidget introduces style properties - these are basically object properties that are stored in the style object associated to the widget.</summary>
Style properties are set in resource files. This mechanism is used for configuring such things as the location of the scrollbar arrows through the theme, giving theme authors more control over the look of applications without the need to write a theme engine in C.
Use <seecref="M:Gtk.Widget.StyleGetProperty"/>, <seecref="M:Gtk.Widget.Style"/> or <seecref="M:Gtk.Widget.StyleGetValist"/> to obtain the value of a style property.
<summary>Makes all newly-created <paramrefname="widgets"/> as composite children until the corresponding <seecref="M:Gtk.Widget.PopCompositeChild"/> call.</summary>
A composite child is a child that's an implementation detail of the container it's inside and should not be visible to people using the container. Composite children aren't treated differently by GTK (but see <seecref="M:Gtk.Container.Foreach"/> vs. <seecref="M:GtkContainer.Forall"/>), but e.g. GUI builders might want to treat them in a different way.
Pushes <paramrefname="cmap"/> onto a global stack of colormaps; the topmost colormap on the stack will be used to create all widgets. Remove <paramrefname="cmap"/> with <seecref="M:Gtk.Widget.PopColormap"/>. There's little reason to use this function.
If the <paramrefname="widget"/> is an unmapped toplevel widget, a <seecref="T:Gtk.Window"/> that has not yet been shown, enter the main loop and wait for the window to actually be mapped. Be careful, because the main loop is running, anything can happen during this function.
The default <paramrefname="widget"/> is activated when the user presses Enter in a window. Default widgets must be activatable, that is, <seecref="M:Gtk.Widget.Activate"/> should affect them. The <paramrefname="widgets"/> must have the <seecref="F:Gtk.WidgetFlags.CanDefault"/> flag set; typically you have to set this flag yourself by calling <seecref="P:Gtk.Widget.CanDefault"/>.
<summary>Moves a <paramrefname="widget"/> from one <seecref="T:Gtk.Container"/> to another, handling reference count issues to avoid destroying the widget.</summary>
<paramname="new_parent">A <seecref="T:Gtk.Container"/> to move the widget into.</param>
Computes the intersection of a <paramrefname="widget"/>'s area and <paramrefname="area"/>, storing the intersection in <paramrefname="intersection"/>, and returns <seecref="langword:true"/> if there was an intersection. <paramrefname="intersection"/> may be <seecref="langword:null"/> if you're only interested in whether there was an intersection.
This function is used by custom widget implementations; if you're writing an app, you'd use <seecref="M:Gtk.Widget.GrabFocus"/> to move the focus to a particular widget, and <seecref="M:Gtk.Container.SetFocusChain"/> to change the focus tab order. So you may want to investigate those functions instead.
<seecref="M:Gtk.Widget.ChildFocus"/> is called by containers as the user moves around the window using keyboard shortcuts. <paramrefname="direction"/> indicates what kind of motion is taking place (up, down, left, right, tab forward, tab backward). <seecref="M:Gtk.Widget.ChildFocus"/> invokes the "focus" signal on <seecref="T:Gtk.Widget"/>; widgets override the default handler for this signal in order to implement appropriate focus behavior.
The "focus" default handler for a widget should return <seecref="langword:true"/> if moving in direction left the focus on a focusable location inside that widget, and <seecref="langword:false"/> if moving in direction moved the focus outside the widget. If returning <seecref="langword:true"/>, widgets normally call <seecref="M:Gtk.Widget.GrabFocus"/> to place the focus accordingly; if returning <seecref="langword:false"/>, they don't modify the current focus location.
For example, <paramrefname="widget"/>->window will be created when a widget is realized. Normally realization happens implicitly; if you show a widget and all its parent containers, then the widget will be realized and mapped automatically. Realizing a widget requires all the widget's parent widgets to be realized; calling <seecref="M:Gtk.Widget.Realize"/> realizes the widget's parents in addition to widget itself. If a widget is not yet inside a toplevel window when you realize it, bad things will happen.
This function is primarily used in widget implementations, and isn't very useful otherwise. Many times when you think you might need it, a better approach is to connect to a signal that will be called after the widget is realized automatically, such as <seecref="F:Gtk.Widget.ExposeEvent"/>. Or simply <seecref="M:Glib.SignalAttr.ConnectAfter"/> to the realize signal.
Invalidates the rectangular area of widget defined by <paramrefname="x"/>, <paramrefname="y"/>, <paramrefname="width"/> and <paramrefname="height"/> by calling <seecref="M:Gdk.Window.InvalidateRect"/> on the widget's window and all its child windows. Once the main loop becomes idle (after the current batch of events has been processed, roughly), the window will receive <seecref="F:Gtk.Widget.ExposeEvent"/> events for the union of all regions that have been invalidated.
Normally you would only use this function in widget implementations. You might also use it, or <seecref="M:Gdk.Window.InvalidateRect"/> directly, to schedule a redraw of a <seecref="T:Gtk.DrawingArea"/> or some portion thereof. Frequently you can just call <seecref="M:Gdk.Window.InvalidateRect"/> or <seecref="M:Gdk.Window.InvalidateRegion"/> instead of this function. Those functions will invalidate only a single window, instead of the widget and all its children.
The advantage of adding to the invalidated region compared to simply drawing immediately is efficiency; using an invalid region ensures that you only have to redraw one time.
<paramname="color">The color to assign (does not need to be allocated), or <seecref="langword:null"/> to undo the effect of previous calls to of <seecref="M:Gtk.Widget.ModifyFg"/>.</param>
<summary>A convenience function that uses the theme engine and RC file settings for <paramrefname="widget"/> to look up <paramrefname="stock_id"/> and render it to a <seecref="T:Gdk.Pixbuf"/>.</summary>
The <paramrefname="stock_id"/> should be a stock icon ID such as <seecref="P:Gtk.Stock.Open"/> or <seecref="P:Gtk.Stock.Ok"/>. <paramrefname="size"/> should be a size such as <seecref="F:Gtk.IconSize.Menu"/>. <paramrefname="detail"/> should be a string that identifies the widget or code doing the rendering, so that theme engines can special-case rendering for that widget or code.
The pixels in the returned <seecref="T:Gdk.Pixbuf"/> are shared with the rest of the application and should not be modified. The <seecref="T:Gdk.Pixbuf"/> should be freed after use with <seecref="M:Glib.Object.Unref"/>.
<paramname="var_args">A va_list of pairs of property names and locations to return the property values, starting with the location for <paramrefname="first_property_name"/>.</param>
<paramname="color">The color to assign (does not need to be allocated), or <seecref="langword:null"/> to undo the effect of previous calls to of <seecref="M:Gtk.Widget.ModifyText"/>.</param>
All other style values are left untouched. The text color is the foreground color used along with the base color (see <seecref="M:Gtk.Widget.ModifyBase"/>) for widgets such as <seecref="T:Gtk.Entry"/> and <seecref="T:Gtk.TextView"/>. See also <seecref="M:Gtk.Widget.ModifyStyle"/>.
<summary>Creates a new <seecref="P:Gtk.Widget.PangoContext"/> with the appropriate colormap, font description, and base direction for drawing text for <paramrefname="widget"/>.</summary>
<returns>The new <seecref="P:Gtk.Widget.PangoContext"/>.</returns>
The function calls <seecref="M:Gtk.Widget.Hide"/> on its argument, then returns <seecref="langword:true"/>. If connected to <seecref="F:Gtk.Widget.DeleteEvent"/>, the result is that clicking the close button for a window (on the window frame, top right corner usually) will hide but not destroy the window. By default, GTK+ destroys windows when <seecref="F:Gtk.Widget.DeleteEvent"/> is received.
Obtains <paramrefname="widget"/>-><paramrefname="requisition"/>, unless someone has forced a particular geometry on the widget, in which case it returns that geometry instead of the widget's <paramrefname="requisition"/>. This function differs from <seecref="M:Gtk.Widget.SizeRequest"/> in that it retrieves the last size request value from <paramrefname="widget"/>-><paramrefname="requisition"/>, while the <seecref="M:Gtk.Widget.SizeRequest"/> method computes the size request and fill in <paramrefname="widget"/>-><paramrefname="requisition"/>, and only then returns <paramrefname="widget"/>-><paramrefname="requisition"/>.
Widget coordinates are a bit odd; for historical reasons, they are defined as <paramrefname="widget"/>->window coordinates for widgets that are not <seecref="F:Gtk.WidgetFlags.NoWindow"/> widgets, and are relative to <paramrefname="widget"/>->allocation.x, <paramrefname="widget"/>->allocation.y for widgets that are <seecref="F:Gtk.WidgetFlags.NoWindow"/> widgets.
The <paramrefname="widget"/> must be a focusable widget, such as a <seecref="T:Gtk.Entry"/>; something like <seecref="T:Gtk.Frame"/> won't work (More precisely, it must have the <seecref="P:Gtk.Widget.CanFocus"/> flag set).
This does not mean that the <seecref="P:Gtk.Widget.HasFocus"/> flag is necessarily set; <seecref="P:Gtk.Widget.HasFocus"/> will only be set if the toplevel widget additionally has the global input focus.
<summary>Given an accelerator group, <paramrefname="accel_group"/>, and an accelerator path, <paramrefname="accel_path"/>, sets up an accelerator in <paramrefname="accel_group"/> so whenever the key binding that is defined for <paramrefname="accel_path"/> is pressed, <paramrefname="widget"/> will be activated.</summary>
This removes any accelerators (for any accelerator group) installed by previous calls to <seecref="M:Gtk.Widget.SetAccelPath"/>. Associating accelerators with paths allows them to be modified by the user and the modifications to be saved for future use.
This function is a low level function that would most likely be used by a menu creation system like <seecref="T:Gtk.ItemFactory"/>. If you use <seecref="T:Gtk.ItemFactory"/>, setting up accelerator paths will be done automatically.
<summary>Installs an accelerator for this <paramrefname="widget"/> in <paramrefname="accel-group"/> that causes <paramrefname="accel_signal"/> to be emitted if the accelerator is activated.</summary>
The <paramrefname="accel-group"/> needs to be added to the widget's toplevel via <seecref="M:Gtk.Window.AddAccelGroup"/>, and the signal must be of type G_RUN_ACTION. Accelerators added through this function are not user changeable during runtime.
Accelerators added through this function are not user changeable during runtime. If you want to support accelerators that can be changed by the user, use <seecref="M:Gtk.Window.SetAccelPath"/> instead.
Any widget that isn't shown will not appear on the screen. If you want to show all the widgets in a container, it's easier to call <seecref="M:Gtk.Widget.ShowAll"/> on the container, instead of individually showing the widgets.
Remember that you have to show the containers containing a widget, in addition to the widget itself, before it will appear onscreen. And that when a toplevel container is shown, it is immediately realized and mapped; other shown widgets are realized and mapped when their toplevel container is realized and mapped.
For <paramrefname="widgets"/> that don't support scrolling, does nothing and returns <seecref="langword:false"/>. <paramrefname="Widgets"/> that don't support scrolling can be scrolled by placing them in a <seecref="T:Gtk.ViewPort"/>, which does support scrolling.
<summary>Creates a new <seecref="T:Pango.Layout"/> with the appropriate colormap, font description, and base direction for drawing text for <paramrefname="widget"/>.</summary>
<paramname="text"> text to set on the layout (can be <seecref="langword:null"/>).</param>
<returns>The new <seecref="T:Pango.Layout"/>.</returns>
If you keep a <seecref="T:Pango.Layout"/> created in this way around, in order notify the layout of changes to the base direction or font of this widget, you must call <seecref="M:Pango.Layout.ContextChanged"/> in response to the <seecref="F:Gtk.Widget.StyleSet"/> and <seecref="F:Gtk-Widget.DirectionChanged"/> signals for the widget.
<summary>Reset the styles of <paramrefname="widget"/> and all descendents, so when they are looked up again, they get the correct values for the currently loaded RC file settings.</summary>
The container uses this information to arrange its child widgets and decide what size allocations to give them with <seecref="M:Gtk.Widget.SizeAllocate"/>. 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.
This function is typically used when implementing a <seecref="T:Gtk.Container"/> subclass. Also remember that the size request is not necessarily the size a widget will actually be allocated.
<summary>Translate coordinates relative to <paramrefname="widget"/>'s allocation to coordinates relative to <paramrefname="dest_widget"/>'s allocations.</summary>
<paramname="dest_x">Location to store X position relative to <paramrefname="dest_widget"/>.</param>
<paramname="dest_y">Location to store Y position relative to <paramrefname="dest_widget"/>.</param>
<returns>Returns <seecref="langword:false"/> if either widget was not realized, or there was no common ancestor. In this case, nothing is stored in <paramrefname="*dest_x"/> and <paramrefname="*dest_y"/>. Otherwise <seecref="langword:true"/>.</returns>
Activation is what happens when you press Enter on a widget during key navigation; clicking a button, selecting a menu item, etc. If the <paramrefname="widget"/> isn't activatable, the function returns <seecref="langword:false"/>.
<paramname="color">The color to assign (does not need to be allocated), or <seecref="langword:null"/> to undo the effect of previous calls of <seecref="M:Gtk.Widget.ModifyBg"/>.</param>
If you want to synthesize an event though, don't use this function; instead, use <seecref="M:Gdk.Windowt.InvalidateRect"/> to invalidate a region of the window.
<paramname="color">The color to assign (does not need to be allocated), or <seecref="langword:null"/> to undo the effect of previous calls to of <seecref="M:Gtk.Widget.ModifyBase"/>.</param>
All other style values are left untouched. The base color is the background color used along with the text color (see <seecref="M:Gtk.Widget.ModifyText"/>) for widgets such as <seecref="T:Gtk.Entry"/> and <seecref="T:Gtk.TextView"/>. See also <seecref="M:Gtk.Widget.ModifyStyle"/>.
For example, <seecref="M:Gtk.Widget.GetAncestor"/>(widget, GTK_TYPE_BOX) gets the first <seecref="T:Gtk.Box"/> that's an ancestor of <paramrefname="widget"/>. No reference will be added to the returned widget; it should not be unreferenced. See note about checking for a toplevel <seecref="T:Gtk.Window"/> in the docs for <seecref="M:Gtk.Widget.Toplevel"/>. Note that unlike <seecref="M:Gtk.Widget.IsAncestor"/>, <seecref="M:Gtk.Widget.GetAncestor"/> considers <paramrefname="widget"/> to be an ancestor of itself.
Modifications made using this technique take precedence over style values set via an RC file, however, they will be overriden if a <paramrefname="style"/> is explicitely set on the <paramrefname="widget"/> using <seecref="M:Gtk.Widget.StyleSet"/>. The <seecref="T:Gtk.RcStyle"/> structure is designed so each field can either be set or unset, so it is possible, using this function, to modify some style values and leave the others unchanged.
Note that modifications made with this function are not cumulative with previous calls to <seecref="M:Gtk.Widget.ModifyStyle"/> or with such functions as <seecref="M:Gtk.Widget.ModifyBg"/>. If you wish to retain previous values, you must first call <seecref="M:Gtk.Widget.ModifierStyle"/>, make your modifications to the returned <paramrefname="style"/>, then call <seecref="M:Gtk.Widget.ModifyStyle"/> with that <paramrefname="style"/>. On the other hand, if you first call <seecref="M:Gtk.Widget.ModifyStyle"/>, subsequent calls to such functions <seecref="M:Gtk.Widget.ModifyFg"/> will have a cumulative effect with the initial modifications.
<summary>Sets the minimum size of a <paramrefname="widget"/>; that is, the <paramrefname="widget"/>'s size request will be <paramrefname="width"/> by <paramrefname="height"/>.</summary>
<paramname="width">Width <paramrefname="widget"/> should request, or -1 to unset.</param>
<paramname="height">Weight <paramrefname="widget"/> should request, or -1 to unset.</param>
You can use this function to force a widget to be either larger or smaller than it normally would be. In most cases, <seecref="M:Gtk.Window.SetDefaultSize"/> is a better choice for toplevel windows than this function; setting the default size will still allow users to shrink the window. Setting the size request will force them to leave the window at least as large as the size request. When dealing with window sizes, <seecref="M:Gtk.Window.SetGeometryHints"/> can be a useful function as well.
Note the inherent danger of setting any fixed size - themes, translations into other languages, different fonts, and user action can all change the appropriate size for a given widget. So, it's basically impossible to hardcode a size that will always be correct. The size request of a widget is the smallest size a widget can accept while still functioning well and drawing itself correctly. However in some strange cases a widget may be allocated less than its requested size, and in many cases a widget may be allocated more space than it requested.
A value of -1 stored in <paramrefname="width"/> or <paramrefname="height"/> indicates that that dimension has not been set explicitly and the natural requisition of the <paramrefname="widget"/> will be used intead. See <seecref="M:Gtk.Widget.SetSizeRequest"/>. To get the size a <paramrefname="widget"/> will actually use, call <seecref="M:Gtk.Widget.SizeRequest"/> instead of this function.
The path is simply the name of a <paramrefname="widget"/> and all its parents in the container hierarchy, separated by periods. The name of a <paramrefname="widget"/> comes from <seecref="P:Gtk.Widget.Name"/>. Paths are used to apply styles to a <paramrefname="widget"/> in gtkrc configuration files. Widget names are the type of the <paramrefname="widget"/> by default (e.g. "<seecref="T:Gtk.Button"/>") or can be set to an application-specific value with <seecref="P:Gtk.Widget.Name"/>.
By setting the name of a <paramrefname="widget"/>, you allow users or theme authors to apply styles to that specific <paramrefname="widget"/> in their gtkrc file. <paramrefname="path_reversed_p"/> fills in the path in reverse order, i.e. starting with <paramrefname="widget"/>'s name instead of starting with the name of <paramrefname="widget"/>'s outermost ancestor.
<summary>Computes the intersection of a <paramrefname="widget"/>'s area and <paramrefname="region"/>, returning the intersection. </summary>
<paramname="region">A <seecref="T:Gdk.Region"/>, in the same coordinate system as <paramrefname="widget"/>->allocation. That is, relative to <paramrefname="widget"/>->window for <seecref="F:Gtk.WidgetFlags.NoWindow"/> widgets; relative to the parent window of <paramrefname="widget"/>->window for widgets with their own window.</param>
<returns> A newly allocated region holding the intersection of <paramrefname="widget"/> and <paramrefname="region"/>. The coordinates of the return value are relative to <paramrefname="widget"/>->window for <seecref="F:Gtk.WidgetFlags.NoWindow"/> widgets, and relative to the parent window of <paramrefname="widget"/>->window for widgets with their own window.</returns>
<summary>Flags a <paramrefname="widget"/> to have its size renegotiated; should be called when a <paramrefname="widget"/> for some reason has a new <seecref="M:Gtk.Widget.SizeRequest"/>.</summary>
This function is only for use in widget implementations. One example, when you change the text in a <seecref="T:Gtk.Label"/>, it queues a resize to ensure there's enough space for the new text.
<summary>Sets the font to use for a <paramrefname="widget"/>.</summary>
<paramname="font_desc">The font description to use, or <seecref="langword:null"/> to undo the effect of previous calls to <seecref="M:Gtk.Widget.ModifyFont"/>.</param>
<summary>Very rarely-used function. This function is used to emit an <seecref="F:Gtk.Widget.ExposeEvent"/> signals on a <paramrefname="widget"/>.</summary>
This function is not normally used directly. The only time it is used is when propagating an <seecref="F:Gtk.Widget.ExposeEvent"/> to a child <seecref="F:Gtk.WidgetFlags.NoWindow"/> widget, and that is normally done using <seecref="M:Gtk.Container.PropagateExpose"/>. If you want to force an area of a window to be redrawn, use <seecref="M:Gdk.Window.InvalidateRect"/> or <seecref="M:Gdk.Window.InvalidateRegion"/>. To cause the redraw to be done immediately, follow that call with a call to <seecref="M:Gdk.Window.ProcessUpdates"/>.
Not a very useful function; most of the time, if you want the style, the <paramrefname="widget"/> is realized, and realized widgets are guaranteed to have a style already.
Adds the events in the bitfield <paramrefname="events"/> to the event mask for <paramrefname="widget"/>. See <seecref="M:Gtk.Widget.Events"/> for details.
Reverts the effect of a previous call to <seecref="M:Gtk.Widget.FreezeChildNotify"/>. This causes all queued <seecref="F:Gtk.Widget.ChildNotified"/> signals on <paramrefname="widget"/> to be emitted.
<summary>Sets a shape for this <paramrefname="widget"/>'s GDK window. This allows for transparent windows etc., see <seecref="M:Gdk.Window.ShapeCombineMask"/> for more information.</summary>
<paramname="shape_mask">Shape to be added, or <seecref="langword:null"/> to remove an existing shape.</param>
Sets a shape for this <paramrefname="widget"/>'s GDK window. This allows for transparent windows etc., see <seecref="M:Gdk.Window.ShapeCombineMask"/> for more information.
<summary>Same as <seecref="M:Gtk.Widget.Path"/>, but always uses the name of a <paramrefname="widget"/>'s type, never uses a custom name set with <seecref="P:Gtk.Widget.Name"/>.</summary>
<paramname="path_length">Location to store the length of the class path, or <seecref="langword:null"/>.</param>
<paramname="path">Location to store the class path as an allocated string, or <seecref="langword:null"/>.</param>
<paramname="path_reversed">Location to store the reverse class path as an allocated string, or <seecref="langword:null"/>.</param>
Same as <seecref="M:Gtk.Widget.Path"/>, but always uses the name of a <paramrefname="widget"/>'s type, never uses a custom name set with <seecref="P:Gtk.Widget.Name"/>.
Equivalent to <seecref="M:Gtk.Object.Destroy"/>, except that you don't have to cast the <paramrefname="widget"/> to <seecref="T:Gtk.Object"/>. When a <paramrefname="widget"/> is destroyed, it will break any references it holds to other objects. If the <paramrefname="widget"/> is inside a container, the <paramrefname="widget"/> will be removed from the container. If the widget is a toplevel (derived from <seecref="T:Gtk.Window"/>), it will be removed from the list of toplevels, and the reference GTK+ holds to it will be removed.
Removing a widget from its container or the list of toplevels results in the <paramrefname="widget"/> being finalized, unless you've added additional references to the <paramrefname="widget"/> with <seecref="M:Glib.Object.Ref"/>.In most cases, only toplevel widgets (windows) require explicit destruction, because when you destroy a toplevel its children will be destroyed as well.
<returns>The reading direction for the widget.</returns>
<remarks>
<para>
This direction controls the primary direction for widgets containing text, and also the direction in which the children of a container are packed. The ability to set the direction is present in order so that correct localization into languages with right-to-left reading directions can be done. Generally, applications will let the default reading direction present, except for containers where the containers are arranged in an order that is explicitely visual rather than logical (such as buttons for text justification). If the direction is set none, then the value set by <seecref="P:Gtk.Widget.DefaultDirection"/> will be used.
<summary>Sets or obtains whether <paramrefname="widget"/> should be mapped along with its when its parent is mapped and <paramrefname="widget"/> has been shown with <seecref="M:Gtk.Widget.Show"/>.</summary>
<paramname="value">If <seecref="langword:true"/>, <paramrefname="widget"/> should be mapped along with its parent.</param>
<returns>Returns <seecref="langword:true"/> if the widget is mapped with the parent.</returns>
<remarks>
<para>
The child visibility can be set for widget before it is added to a container with <seecref="P:Gtk.Widget.Parent"/>, to avoid mapping children unnecessary before immediately unmapping them. However it will be reset to its default state of <seecref="langword:true"/> when the widget is removed from a container.
</para>
<para>
Note that changing the child visibility of a widget does not queue a resize on the widget. Most of the time, the size of a widget is computed from all visible children, whether or not they are mapped. If this is not the case, the container can queue a resize itself. This function is only useful for container implementations and never should be called by an application.
<summary>Sets or obtains a <paramrefname="widget"/> composite name.</summary>
<paramname="value">The name to set.</param>
<returns>The composite name of <paramrefname="widget"/>, or <seecref="langword:null"/> if <paramrefname="widget"/> is not a composite child. The string should not be freed when it is no longer needed.</returns>
<remarks>
<para>
The widget must be a composite child of its parent; see <seecref="M:Gtk.Widget.PushCompositeChild"/>.
<summary>Obtains the topmost widget in the container hierarchy <paramrefname="widget"/> is a part of.</summary>
<returns>The topmost ancestor of <paramrefname="widget"/>, or <paramrefname="widget"/> itself if there's no ancestor.</returns>
<remarks>
<para>
Note the difference in behavior against <seecref="P:Gtk.Widget.GetAncestor"/>, would return <seecref="langword:null"/> if <paramrefname="widget"/> wasn't inside a toplevel window, and if the window was inside a GtkWindow-derived widget which was in turn inside the toplevel <seecref="T:Gtk.Window"/>. While the second case may seem unlikely, it actually happens when a <seecref="T:Gtk.Plug"/> is embedded inside a <seecref="T:Gtk.Socket"/> within the same application. To reliably find the toplevel <seecref="T:Gtk.Window"/>, use <seecref="P:Gtk.Widget.TopLevel"/> and check if the <seecref="F:Gtk.WidgetFlags.TopLevel"/> flag is set on the result.
<paramname="value"><seecref="langword:true"/> the entire widget will be redrawn when it is allocated to a new size. <seecref="langword:false"/> only the new portion of the widget will be redrawn.</param>
By default, this setting is <seecref="langword:true"/> and the entire <paramrefname="widget"/> is redrawn on every size change. If your widget leaves the upper left are unchanged when made bigger, turning this setting on will improve performance.
Note that for <seecref="F:Gtk.WidgetFlags.NoWindow"/> widgets setting this flag to <seecref="langword:false"/> turns off all allocation on resizing: the widget will not even redraw if its position changes; this is to allow containers that don't draw anything to avoid excess invalidations. If you set this flag on a <seecref="F:Gtk.WidgetFlags.NoWindow"/> widget that does draw on <paramrefname="widget"/>->window, you are responsible for invalidating both the old and new allocation of the <paramrefname="widget"/> when the widget is moved and responsible for invalidating regions newly when the <paramrefname="widget"/> increases size.
<paramname="value"><seecref="langword:true"/> is on by Default, <seecref="langword:false"/> if you want to turn off double buffering no use call for true because it is default.</param>
<returns>Returns <seecref="langword:true"/> because double buffering is on by Default, but returns <seecref="langword:false"/> if you turn it off.</returns>
Widgets are double buffered by default, you can use this function to turn off the buffering. "Double buffered" simply means that <seecref="M:Gdk.Window.BeginPaintRegion"/> and <seecref="M:Gdk.Window.EndPaint"/> are called automatically around <seecref="F:Gtk.Widget.ExposeEvent"/> events sent to the widget. <seecref="M:Gdk.Window.BeginPaint"/> diverts all drawing to a <paramrefname="widget"/>'s window to an offscreen buffer, and <seecref="M:Gdk.Window.EndPaint"/> draws the buffer to the screen. The result is that users see the window update in one smooth step, and don't see individual graphics primitives being rendered.
In very simple terms, double buffered widgets don't flicker, so you would only use this function to turn off double buffering if you had special needs and really knew what you were doing.
<summary>Obtains the settings object holding the settings (global property settings, RC file information, etc) used for this <paramrefname="widget"/>.</summary>
Note that this function can only be called when the <seecref="T:Gtk.Widget"/> is attached to a toplevel, since the settings object is specific to a particular <seecref="T:Gdk.Screen"/>.
<summary>Obtains a <seecref="T:Pango.Context"/> with the appropriate colormap, font description and base direction for <paramrefname="widget"/>.</summary>
<returns></returns>
<remarks>
<para>
Unlike the context returned by <seecref="M:Gtk.Widget.CreatePangoContext"/>, this context is owned by the <paramrefname="widget"/> (it can be used until the screen for the widget changes or the widget is removed from its toplevel), and will be updated to match any changes to the <paramrefname="widget"/>'s attributes.
</para>
<para>
If you create and keep a <seecref="T:Pango.Layout"/> using this context, you must deal with changes to the context by calling <seecref="T:Pango.Layout.ContextChanged"/> on the layout in response to the <seecref="F:Gtk.Widget.StyleSet"/> and <seecref="F:Gtk.Widget.DirectionChanged"/> signals for the <paramrefname="widget"/>.
<summary>Sets the state of a <paramrefname="widget"/> (insensitive, prelighted, etc.).</summary>
<paramname="value">New state for <paramrefname="widget"/>.</param>
<returns>The <seecref="T:Gtk.StateType"/> of the <paramrefname="widget"/>.</returns>
<remarks>
<para>
Usually you should set the state using wrapper functions such as <seecref="P:Gtk.Widget.Sensitive"/>. This function is for use in widget implementations.
<summary>Obtains the current modifier style for the widget.(As set by <seecref="M:Gtk.Widget.ModifyStyle"/>)</summary>
<returns>The modifier style for the widget. This rc style is owned by the widget.</returns>
<remarks>
<para>
If no style has previously set, a new <seecref="T:Gtk.RcStyle"/> will be created with all values unset, and set as the modifier style for the widget. If you make changes to this rc style, you must call <seecref="M:Gtk.Widget.ModifyStyle"/>, passing in the returned rc style, to make sure that your changes take effect.
</para>
<para>
Caution: passing the style back to <seecref="M:Gtk.Widget.ModifyStyle"/> will normally end up destroying it, because <seecref="M:Gtk.Widget.ModifyStyle"/> copies the passed-in style and sets the copy as the new modifier style, thus dropping any reference to the old modifier style. Add a reference to the modifier style if you want to keep it alive.
<returns>Creates a new instance of Widget, using the GLib-provided type</returns>
<remarks>
<para>This is a constructor used by derivative types of <seecref="T:Gtk.Widget"/> that would have their own GLib type assigned to it. This is not typically used by C# code.</para>