Databases Reference
In-Depth Information
Term
Description
The flexibility with templates is that developers can
actually modify these templates, creating a standard
template that is used throughout the entire application
or workspace. For instance, simply by modifying an
existing button template to include a width tag
<button width="300px"
all buttons in the entire application would instantly
have a width of 300 pixels wide. In fact, developers can
even change the HTML entirely, replacing <button> tags
with <img> tags to create image buttons.
Theme
Every type of control and user interface element in APEX
is represented by a template. A complete collection of
these templates is known as a theme. In other words, a
theme is a collection of templates.
Themes make it easy for your developers to skin your
applications and switch from one theme to another with
a few clicks of the mouse.
Substitution String
In the button template example, you might have noticed
special tags like #LABEL# (phrases enclosed between
two hash symbols (#)). These are called substitution
strings and provide an easy way for developers to insert
dynamic fields in a template.
For instance, #LABEL# actually represents the text that
will be displayed on top of the button. They are
substituted with actual values (in this case, the button
text) when your form is rendered by APEX. Try to think
of it as mail merge.
In this fashion, you could reposition and move these
substitution strings around to achieve interesting
effects. For instance, you could write an onclick
JavaScript handler to prompt a confirmation box that
displays the text of the button as part of its message
using the #LABEL# substitution string.
<button value="#LABEL#" onclick="if (confirm('Are
you sure you wish to click the #LABEL# button'))
#LINK#" ...
Now that you know these terms, let's look at how user-uploaded images are used in APEX. APEX treats
images as resources that can be reused many times within an application or within a workspace. The
first step before you can use any images in your application is to import it. The
Shared Components
area
of your application, as its name indicates, is a global area where pages can reference to retrieve an image
resource.
