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(gtk.info)GtkAlignment

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The alignment widget
====================

Description
-----------

   The alignment widget is a container (Note: GtkContainer) derived
from the bin widget (Note: GtkBin). Its entire purpose is to give the
programmer flexibility in how the child it manages is positioned when a
window is resized.

   Normally, a widget is allocated at least as much size as it
requests. (Note: GtkContainer for a discussion of geometry
management). When a widget is allocated more size than it requests there
is a question of how the widget should expand. By convention, most GTK
widgets expand to fill their allocated space. Sometimes this behavior is
not desired. The alignment widget allows the programmer to specify how a
widget should expand and position itself to fill the area it is
allocated.

Options
-------

 - User Option: xscale
 - User Option: yscale
     The XSCALE and YSCALE options specify how to scale the child
     widget. If the scale value is 0.0, the child widget is allocated
     exactly the size it requested in that dimension. If the scale
     value is 1.0, the child widget is allocated all of the space in a
     dimension. A scale value of 1.0 for both x and y is equivalent to
     not using an alignment widget.

 - User Option: xalign
 - User Option: yalign
     The XALIGN and YALIGN options specify how to position the child
     widget when it is not allocated all the space available to it
     (because the XSCALE and/or YSCALE options are less than 1.0). If
     an alignment value is 0.0 the widget is positioned to the left (or
     top) of its allocated space. An alignment value of 1.0 positions
     the widget to the right (or bottom) of its allocated space. A
     common usage is to specify XALIGN and YALIGN to be 0.5 which
     causes the widget to be centered within its allocated area.

Signals
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Functions
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 - Function: guint gtk_alignment_get_type (void)
     Returns the `GtkAlignment' type identifier.

 - Function: GtkWidget* gtk_alignment_new (gfloat XALIGN, gfloat
          YALIGN, gfloat XSCALE, gfloat YSCALE)
     Create a new `GtkAlignment' object and initialize it with the
     values XALIGN, YALIGN, XSCALE and YSCALE. The new widget is
     returned as a pointer to a `GtkWidget' object. `NULL' is returned
     on failure.

 - Function: void gtk_alignment_set (GtkAlignment *ALIGNMENT, gfloat
          XALIGN, gfloat YALIGN, gfloat XSCALE, gfloat YSCALE)
     Set the XALIGN, YALIGN, XSCALE and YSCALE options of an alignment
     widget. It is important to not set the fields of the
     `GtkAlignment' structure directly (or, for that matter, any type
     derived from `GtkObject').

 - Function: GtkAlignment* GTK_ALIGNMENT (gpointer OBJ)
     Cast a generic pointer to `GtkAlignment*'. Note: Standard
     Macros, for more info.

 - Function: GtkAlignmentClass* GTK_ALIGNMENT_CLASS (gpointer CLASS)
     Cast a generic pointer to `GtkAlignmentClass*'. Note: Standard
     Macros, for more info.

 - Function: gint GTK_IS_ALIGNMENT (gpointer OBJ)
     Determine if a generic pointer refers to a `GtkAlignment' object.
     Note: Standard Macros, for more info.