[geojquery] Playing with the prototype GeojQuery Widget

[Anne Blankert]

 Hello list,

I do like how the ui-widgets work, although they add a dependency on
jquery-ui. I did not find full reference documentation though, is there
one on-line?
In my attempt at creating a mapwidget plugin, I tried to depend on
jQuery only and wrap jQuery-ui widgets (like 'layout', 'dialog' or
'sortable') around them.

So where do we go from here? Many of the widgets do not require
jQuery-ui. At this moment I think only a widget like 'sortableLegend'
would require jQuery-ui.
Volker proposes we implement a subset of the widget factory ourselves.

According to
http://bililite.com/blog/understanding-jquery-ui-widgets-a-tutorial/ the
core problem of plugins are memory management:
Memory leaks me be caused by DOM elements referencing Javascript
elements and vice versa. jQuery solved this by adding the $.fn.data
plugin, but this results in a lot of bookkeeping.

The jQuery-ui widgets generally work as follows:

// create the widget
$.widget("widgetName", WidgetClass);

// now instantiate the widget in the DOM
$(selector).widgetName({defaultOption1: value1, defaultOption2: value2});

// use some WidgetClass methods
// call a chainable WidgetClass setter named 'setterMethod':
$(selector).widgetName('setterMethod', setterParameter1, setterParameter2);

// call a WidgetClass getter named 'getterMethod'
var aValue = $(selector).widgetName('getterMethod', getterParameter1,
getterParameter2);

Now if we want get rid of the jQuery-ui dependency, we may still want
the to be able to do something like:

// instantiate geoMap
$(selector).geoMap ({ olMap: myOlMap, allOverlays: false});

// use a setter method:
$(selector).geoMap(‘layer’, ‘blue_marble’, {
'type': 'WMS',
'label': 'Blue Marble',
'url': 'http://sigma.openplans.org/geoserver/gwc/service/wms?',
'layers': 'bluemarble'
});

// get the class instance:
var myMap = $(selector).geoMap('geoMap');

// get some value
var myValue = $(selector).geoMap('getOption', 'keyName');

// set some value
$(selector).geoMap('setOption', 'keyName', keyValue);

I think the above examples can be done without the need for the
jQuery-ui widget factory. I think I even see some advantages of not
using the widget factory here.

What kind of functionality would we lose if we let go of the jQuery-ui
widget factory altogether?

Anne