Patch dojo.parser, OR stop putting widget code in event callbacks such as onShow, onRezised etc

[mumme]

Connecting to onShow in markup using TitlePane?, StackContainer? TabContainer? etc breaks href load.

This is just a symptom of a bigger problem. Say a designer wants to know when a TitlePane? shows

<div dojoType='dijit.TitlePane'  
    href='somepage'
    open='false'
    title='Foo'
    onShow='console.debug("opened")'
></div>

When dojo.parser parses this markup it replaces TitlePane?'s onShow function, which currently triggers the href download, with:

function(){console.debug("opened")}

So we either patch the parser to connect instead of replace OR stop using public functions in widget to widget calls (not sure that is possible in all cases).

I suspect it has been discussed extensively already, still code like this is still being added to dijit trunk. I searched trac but couldn't find any tickets filed about this yet. So I figured I open a ticket to make people aware of this.

/ Fredrik

[bill]

Right, doing onShow=... in the parser does a replace rather than a connect by design, so that you can define a function that returns a value, like

   <div dojoType=Graph f="return arguments[0]+1">

or something like that.

So we need to change onShow to _onShow and make onShow empty, like:

  onShow: function(){ // summary: user defined callback to ... }
  _onShow: function(){  do stuff and then call this.onShow(); }

Can you do this?

[mumme]

Ok thanks for clearing that out, I suppose it's a question of what people use most, functions as events, or functions as mutators.

Yes I can for this particular case, it's the reason I only had _loadCheck in the first place in ContentPane?.

But I wont do Menu.js: onCancel, onItemHover, onItemUnHover, onItemClick, onOpen, onClose

nor Button.js onClick(2 places)

nor ValidationTextbox?.js onfocus, onblur, onkeyup (lowercased why??)

nor FilteringSelect?.js onkeyup (lowercased ??)

nor TimeTextbox? onfocus (lowercased ??)

nor Slider.js onMouseMove

nor ComboBox?.js onkeypress, onfocus, onblur, onmouseover, onmouseout (lowercased ??), onClose, onClick

nor Checkbox.js onClick

nor Textbox.js onfocus (lowercased ??)

nor Dialog.js onLoad, onOpen

These are just a quick scan, this problem is bigger than just changing 1 file, IMHO all widget creators must be aware of this and code accordingly.

I'm assigning this back to you Bill, you probably know how to assign issues in the files above.

/ Fredrik

[bill]

• Most of those functions should have _ in front of them (like Menu.js).
• Button.js is not an issue because it's ok to override that function.
• ValidationTextBox?, FilteringSelect?, TimeTextbox? is using syntax like dojoAttachEvent="onfocus" rather than dojoAttachEvent="onfocus:_onFocus" but that makes the functions seem public so we should probably change it

and so forth. Will fix for 1.1

[mumme]

(In [9876]) Dont use public event methods in widget to widget infrastructure, public events like onShow might be overridden from markup by dojo.parser.

refs #3905

[Adam Peller]

Bill, I wonder if using attributemap (#3058) cascading the parsed handler with the template handler, the way we do with class and style attributes, might help here.

[bill]

PS: I marked this as low priority because the user can now easily connect to a method rather than overriding it by doing a <script type="dojo/connect" event="onShow"> ...

[alex]

Milestone 2.0 deleted

[bill]

The issue is that sometimes the specified function is intended to overwrite, rather than connecting. The two examples I've found are dijit.form.Form (onSubmit), and dijit.form.Button (onClick). In both cases the function returning false will cancel the form submit.

[bill]

This is effectively fixed in ​delite/​deliteful, since events like show/hide are emitted as actual events, and there aren't callback methods. So, closing this as fixed in 2.0.