NAME¶

Tk::ObjScanner - a GUI to scan any perl data structure or object

SYNOPSIS¶

    # regular use
    use Tk::ObjScanner;
    my $mw  = MainWindow->new;
    my $scanner1 = $mw->ObjScanner(
        -caller => $object,
        -title=>"windows"
    )->pack;
    my $scanner2 = $mw->ObjScanner(
        -caller             => $object,
        -title              => 'demo setting the scanner options',
        -background         => 'white',
        -selectbackground   => 'beige',
        -foldImage          => $mw->Photo(-file => Tk->findINC('folder.xpm')),
        -openImage          => $mw->Photo(-file => Tk->findINC('openfolder.xpm')),
        -itemImage          => $mw->Photo(-file => Tk->findINC('textfile.xpm')),
    )->pack( -expand => 1, -fill => 'both' ) ;
    # non-intrusive scan style
    # user code to produce data
    Tk::ObjScanner::scan_object($mydata) ;
    # resume user code

DESCRIPTION¶

The scanner provides a GUI to scan the attributes of an object. It can also be used to scan the elements of a hash or an array.

This widget can be used as a regular widget in a Tk application or can be used as an autonomous popup widget that will display the content of a data structure. The latter is like a call to a graphical Data::Dumper. The scanner can be used in an autonomous way with the "scan_object" function.

The scanner is a composite widget made of a menubar and Tk::HList. This widget acts as a scanner to the object (or hash ref) passed with the 'caller' parameter. The scanner will retrieve all keys of the hash/object and insert them in the HList.

When the user double clicks on a key, the corresponding value will be added in the HList.

If the value is a multi-line scalar, the scalar will be displayed in a popup text window. Code ref will be deparsed and shown also in the pop-up window.

Tied scalar, hash or array internal can also be scanned by clicking on the middle button to open them.

Weak references are recognized (See WeakRef for details)

Autonomous widget¶

  Tk::ObjScanner::scan_object($data);

Constructor parameters¶

"caller"

The ref of the object or hash or array to scan (mandatory). (you can also use '"-caller"')

"-title"

The title of the menu created by the scanner (optional)

"-background"

The background color for subwidgets (optional)

"-selectbackground"

The select background color for HList (optional)

"-itemImage"

The image for a scalar item (optional, default 'file.xbm')

"-foldImage"

The image for a composite item (array or hash) when closed (optional, default 'folder.xbm')

"-openImage"

The image for a composite item (array or hash) when open (optional, default 'openfolder.xbm')

"-show_menu"

ObjScanner can feature a menu with 'reload' button, 'show tied info'. (optional default 0).

"-destroyable"

If set, a menu entry will allow the user to destroy the scanner widget. (optional, default 1) . You may want to set this parameter to 0 if the destroy can be managed by a higher level object. This parameter is ignored if show_menu is unset.

"-destroy_label"

Label to be used for "destroy" menu entry.

"-show_tied"

If set, will indicate if a variable is a tied variable. You can see the internal data of the tied variable by double clicking on the middle button. (default 1)

WIDGET-SPECIFIC METHODS¶

CAVEATS¶

The name of the widget is misleading as any data (not only object) may be scanned. This widget is in fact a DataScanner.

ObjScanner may fail if an object involves a lot of internal perl magic. In this case, I'd be glad to hear about and I'll try to fix the problem.

ObjScanner does not detect recursive data structures. It will just keep on displaying the tree until the user gets tired of clicking on the HList items.

The icon used for tied scalar changes from scalar icon to folder icon when opening the object hidden behind the tied scalar (using the middle button). I sure could use a better icon for tied items. (hint hint)

THANKS¶

To Rudi Farkas for all the improvements provided to ObjScanner.

To Slaven Rezic for:

•

The idea to use B::Deparse to view code ref.

CONTRIBUTORS¶

Many thanks to Achim Bohnet for all the tests, patches (and reports) he made. Many improvements were made thanks to his efforts.

Thanks to Rudi Farkas for the 'watch' patch.

Thanks to heytitle for the documentation fixes

AUTHOR¶

Dominique Dumont, ddumont@cpan.org

SEE ALSO¶

perl, Tk, Tk::HList, B::Deparse, data_viewer