Tutorial 11: Conditionally Visible Form Items (Palm OS)
Product: HanDBase Forms for Palm OS
Article Number: 305
Creation Date: 12/07/2007
- Topic:Conditional Display of UI Elements on Forms
- Product:
HanDBase Forms
- Version:
4.0
- Date:
November 24, 2007
- HandheldOS:Palm OS
- DesktopOS:
Windows
Tutorial:
This tutorial's goal is to introduce
the ability to conditionally display UI elements as a new feature in
HanDBase
Forms 4.0.This feature's main function
is to allow or disallow UI elements to be displayed based on the value
or state
of another field.Being able to
conditionally display UI elements extends the previous functionality of
HanDBase Forms by allowing users to create more customized, intuitive
user
interfaces for collecting data.A
practical example of this might be in the creation of grocery shopping
list, an
inventory system or attendance monitor.In this tutorial, the necessary steps to configure HanDBase
Forms to
take advantage of this new feature will be detailed.Then, the results of properly configuring
conditionally displaying user interface elements will be examined.Finally, additional resources will be
provided should any further information be needed.
To take advantage of the conditional
display of UI elements HanDBase 4 and HanDBase Forms 4 needs to be
configured
on the handheld device.The first step
in doing so is to launch HanDBase in the manner most appropriate for
the
particular model of handheld being used.Once running, the first steps in configuring are:
Step #1:
a)Create
a new database in HanDBase using the following
configuration.
Database Title = "Grocery"
Field 1 - Name="Item", Type="Text"
Field 2 - Name="Purchase",
Type="Check-Box"
Field 3 - Name="Quantity",
Type="Integer"
Field 4 – Name=”Category”, Type=”Text”
Step #2:
a)Once
the "Grocery" database has been created a
form needs to be created that is associated with it.To accomplish this, highlight it in the list
and select the "details" button in the lower right corner of the
screen.
b)Once
the next form displays, select the "Forms"
option on the right side of the screen.
c)Configure
the properties of the form, such as the name,
background color and default buttons in the next dialog.
d)After
finished, click "ok".
e)The
next form appears as a grid with three buttons along the
bottom, being "New", "Details" and "Delete".
Step #3:
a)The
next step is to place the UI elements on the form.
b)Start
by placing text labels on the grid that correspond to
each of the four field names.
c)The
next step is to place UI elements next to each of the
respective field names.For the “Item”
field, place a Text Box.
d)For
the “Purchase” field, a Check-Box.
e)Again,
place a Text Box for the “Quantity” field and finally
a Pop-Up for the “Category” field.See
the illustration below for an example of this.
f)The
final step is to set the visibility of certain elements
on the form to only be visible based on the value of another field.For this example, the value of the Purchase
field will determine whether or not the Quanity and Category field
information
is shown.If the value of the Purchase
field is zero (0) or the checkbox is unchecked, then the Quantity and
Category
fields are not visible.If the value is
one, or the box is checked, then the fields are visible so that data
can be
entered into them.
g)To
configure this, select each of the items one at a time
and tap the “Details…” button.
h)On
the Attributes tab, set the “visible” option to
conditionally.
i)Choose
the field that is to have a non-zero value to be the
“Purchase” field.
j)The
screenshot on the left illustrates configuring this
option for the text field while the screenshot on the right illustrates
it for
the popup and labels.
After setting up HanDBase Forms 4 to
make use of the ability to conditionally display UI elements on the
form, when
editing data in the form or when adding a new record, toggling the
Purchase
checkbox will indicate whether or not the Quantity and Category UI
items are
visible.
To summarize, this tutorial has
introduced the ability to conditionally display UI elements as one of
the many
new features in HanDBase Forms 4.Additional resources, if needed, can be found at:
