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## -*- texinfo -*-
## @deftypefn  {} {@var{hui} =} uicontrol ()
## @deftypefnx {} {@var{hui} =} uicontrol (@var{property}, @var{value}, @dots{})
## @deftypefnx {} {@var{hui} =} uicontrol (@var{parent})
## @deftypefnx {} {@var{hui} =} uicontrol (@var{parent}, @var{property}, @var{value}, @dots{})
## @deftypefnx {} {} uicontrol (@var{h})
##
## Create a uicontrol object and return a handle to it.
##
## A uicontrol object is used to create simple interactive controls such as
## push buttons, checkboxes, edit and list controls.
##
## If @var{parent} is omitted then a uicontrol for the current figure is
## created.  If no figure is available, a new figure is created first.
##
## If @var{parent} is given then a uicontrol relative to @var{parent} is
## created.
##
## Any provided property value pairs will override the default values of the
## created uicontrol object.
##
## The full list of properties is documented at @ref{Uicontrol Properties}.
##
## The type of uicontrol created is specified by the @var{style} property.  If
## no style property is provided, a push button will be created.
##
## Valid styles for uicontrol are:
##
## @table @asis
## @item @qcode{"checkbox"}
## Create a checkbox control that allows user on/off selection.
##
## @item @qcode{"edit"}
## Create an edit control that allows user input of single or multiple lines
## of text.
##
## @item @qcode{"listbox"}
## Create a listbox control that displays a list of items and allows user
## selection of single or multiple items.
##
## @item @qcode{"popupmenu"}
## Create a popupmenu control that displays a list of options that can be
## selected when the user clicks on the control.
##
## @item @qcode{"pushbutton"}
## Create a push button control that allows user to press to cause an action.
##
## @item @qcode{"radiobutton"}
## Create a radio button control intended to be used for mutually exclusive
## input in a group of radiobutton controls.
##
## @item @qcode{"slider"}
## Create a slider control that allows user selection from a range of values
## by sliding knob on the control.
##
## @item @qcode{"text"}
## Create a static text control to display single or multiple lines of text.
##
## @item @qcode{"togglebutton"}
## Create a toggle button control that appears like a push button but allows
## the user to select between two states.
##
## @end table
##
## Examples:
##
## @example
## @group
## ## Create figure and panel on it
## f = figure;
## ## Create a button (default style)
## b1 = uicontrol (f, "string", "A Button", ...
##                    "position", [10 10 150 40]);
## ## Create an edit control
## e1 = uicontrol (f, "style", "edit", "string", "editable text", ...
##                    "position", [10 60 300 40]);
## ## Create a checkbox
## c1 = uicontrol (f, "style", "checkbox", "string", "a checkbox", ...
##                    "position", [10 120 150 40]);
## @end group
## @end example
##
## When called with a single argument @var{h} which is a handle to an existing
## uicontrol object, switch the keyboard focus to the specified
## uicontrol.  As a result, the uicontrol object will receive keyboard
## events that can be processed using the @qcode{"keypressfcn"} callback.
## @seealso{figure, uipanel}
## @end deftypefn

function hui = uicontrol (varargin)

  if (nargin == 1 && isgraphics (varargin{1}, "uicontrol"))
    set (varargin{1}, "__focus__", "on");
    return;
  endif

  [h, args] = __uiobject_split_args__ ("uicontrol", varargin,
                                       {"figure", "uipanel", "uibuttongroup"});

  ## Validate style
  idx = find (strcmpi (args(1:2:end), "style"), 1, "last");
  if (! isempty (idx) && 2*idx <= numel (args))
    if (strcmpi (args{2*idx}, "frame"))
      warning ("Octave:unimplemented-matlab-functionality",
               'uicontrol: "frame" style is not implemented.  Use uipanel() or uibuttongroup() instead');
    endif
  endif

  htmp = __go_uicontrol__ (h, args{:});

  if (nargout > 0)
    hui = htmp;
  endif

endfunction


%!warning <"frame" style is not implemented>
%! hf = figure ("visible", "off");
%! unwind_protect
%!   h = uicontrol (hf, "string", "Hello World", "Style", "frame");
%! unwind_protect_cleanup
%!   close (hf);
%! end_unwind_protect