Functions
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In HyperCard 2.x, as in previous versions of HyperCard, once a field is
locked, it can handle mouse clicks just as HyperCard buttons. In HyperCard
2.x, all of the text within a locked field becomes eligible for use as a
trigger for action. When a user clicks within the text of a locked field,
three new HyperTalk functions, the clickText, the clickChunk, and the
clickLine, are available to return information about the click. With these
functions, a handler can determine which text string the user clicked and
respond accordingly.
* The clickText function returns the actual text that was clicked.
* The clickChunk function returns a chunk expression that describes the
text that was clicked -- for example, "char 1 to 3 of bkgnd field 3".
* The clickLine function returns a chunk expression describing the line
that was clicked -- for example, "line 5 of card field 2".
Remember that the HyperTalk definition of a line is determined by carriage
returns, not by the way the lines are wrapped in a field. By default, all
text is grouped into words, and the clickText and clickChunk functions will
return information about the word that was clicked.
The following example handler -- which can be placed in the script of a
locked field, a card, a background, or a stack -- performs a simple
glossary lookup using hot text.
on mouseUp
lock screen
put the clickText into whatWasClicked -- must be done before leaving card
go stack ""
find whatWasClicked in field "" -- is it a glossary entry?
if the result is not empty then -- not found
go back
unlock screen -- looks like nothing happened
else unlock screen with visual effect dissolve -- shows glossary entry
end mouseUp
Other examples of hot text:
on mouseUp
if the clickText is "" then show card field ""
-- pops up definition of ""
end mouseUp
on mouseUp
if the textStyle of the clickChunk is bold then show cd fld ""
if the textStyle of the clickChunk is italic then show cd fld ""
-- In this field, a click on an italicized word has a different effect
-- from a click on a bold word.
-- This works because clickChunk returns a chunk expression,
-- and in HyperCard 2.0 chunks of text have properties.
end mouseUp
Group Text Style
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As a way to override the standard grouping of text, HyperCard 2.x
introduces a new text style: Group. By selecting a string of text within a
field and choosing Group from the Style menu, designers can "stick" words
or characters together so that they can be used more intelligently within
scripts.
Grouping affects only the value of the clickText, the clickChunk, and the
clickLine functions when text within the string is clicked. When such a
click occurs, the clickText and clickChunk functions return information
about the entire group, instead of just the individual word that was
clicked. The clickLine function returns the line number of the first
character of the group.
To illustrate the effect of grouping text, say we have a list containing
the names Billy Bob, Billy "Bob" Smith, and Billy Smith, and we wish to
have more information about each of these individuals appear on the screen
when his name is clicked. Unless their names were grouped, HyperCard
wouldn't know what to do when the user clicked the word Billy -- the
clickText function would return only that single word. If we select each
of the full names and set its text style to Group from the Style menu, the
clickText function will return the full name when any part of it is
clicked.
By itself, the Group text style makes no visible change to the appearance
of text -- but you can find the grouped text in a field through the
commands Show and Hide. The command "show groups" will draw a 2-pixel high
gray line under all grouped text. Grouped text will be shown throughout
the current session with HyperCard until the Hide Groups command is sent.
For example:
show groups -- shows a 2-pixel gray line under all grouped text on the card
hide groups -- hides the gray lines
Keep in mind that showing groups will not necessarily identify all Hot
Text, as hypertext responses from text in fields can be keyed to words,
line number, character position, text style, text size, font, or special
characters in words.
Note the differences: with Hot text, HyperCard always knows exactly which
words in a field a user clicked: you can then tell HyperCard how to respond
to that click. For example, you can write a script that tells HyperCard to
display a hidden pop-up field that appears only when a user clicks on a
specific word. When using Grouped Text, you can write scripts that tell
HyperCard what to do when users click entire groups of words.
Shared Text
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This feature appears in the Field Info dialog box. Shared text means that
you only need to enter text once in a background field and the text will
appear on every card with that background. Shared text can be activated as
Hot Text.
This article is adapted from the Claris Tech Info database.