> I am curious though, why did the story.findContainingTiddler(place);
> throw an error? Also, I noticed that sometimes, it is used as
> story.findContainingTiddler(this);. Can someone explain the reason?
'place' is the current DOM element into which wiki source content is
being rendered. 'tiddler' is the current tiddler object in which that
wiki source content is stored. These values are passed into each
macro.handler() function, so that macros can produce suitable output.
In addition, 'place' and 'tiddler' are also defined as global
variables (i.e., window.place and window.tiddler) that are
automatically set by the TWCore. This allows fields from these
objects to be referenced from within *evaluated parameters* in a macro
(e.g. <<someMacro {{tiddler.title}}>>).
'place' and 'tiddler' are also automatically defined by
InlineJavascriptPlugin, so that these global variables are also
available for use within inline scripting.
In contrast, 'this' is an automatic 'context variable' defined by the
browser's Javascript runtime environment, and is a reference to the
current object within the scope of the function being processed.
This is particularly important when processing an event handler (such
as onclick="..."). In the context of the handler, 'this' refers to
the object associated with the handler function (i.e., the link
element that was clicked on).
Summary:
When writing macro code (or inline Javascript code), use 'place' to
refer to the element that triggered the event processing. When
writing embedded HTML handlers (i.e., onclick="..."), use 'this' for
the same purpose.
Note: InlineJavascriptPlugin has special handling for 'place'.
Normally, 'place' refers to the DOM element in which the script is
embedded, so that script output can be inserted in place of the script
itself. However, when using the label="..." optional syntax to create
an onClick handler, 'place' refers to the clicked link element (i.e.,
just like the browser-internal 'this') so that you can
programmatically adjust the link element (e.g., change it's text when
it is clicked on). In this specific use-case, you will need to refer
to 'place.parentNode' to generate and render script output (which will
follow the clickable link element).
enjoy,
-e
Eric Shulman
TiddlyTools / ELS Design Studios
HELP ME TO HELP YOU - MAKE A CONTRIBUTION TO MY "TIP JAR"...
http://www.TiddlyTools.com/#Donations
Professional TiddlyWiki Consulting Services...
Analysis, Design, and Custom Solutions:
http://www.TiddlyTools.com/#Contact
--
You received this message because you are subscribed to the Google Groups
"TiddlyWiki" group.
To post to this group, send email to tiddlywiki@googlegroups.com.
To unsubscribe from this group, send email to
tiddlywiki+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/tiddlywiki?hl=en.
