2 Visual Components Manuals

Introduction to Visual Components 2.3
4.8.3.3 Application Possibilities
This section contains a few examples concerning the use of status bits. It is not possible to completely cover all
of the details of such an implementation in this section. Applications and concrete examples in C and
Automation Basic can be found in the Tips and Tricks section.
• Synchronized Data Acquisition Over a Network
Transporting variables from remote stations can be coordinated using the EditAction bit (15). By default,
active variables are read cyclically and then displayed.
If the variable's EditActive bit changes from 0 to 1, then this field was opened to be edited on the
visualization unit. Cyclic reading for the respective variable must be disabled until the input is complete.
This is indicated when the bit switches back to 0. This means that this variable can be written back to
the remote station. As an option, the value can be checked to make sure it is within permitted
boundaries.
When completed, the variable is activated again for cyclic reading.
• Configurable Visualization
By default, Visual Components does not support a dynamic visualization arrangement on the runtime
system. Such behavior can be partially reproduced using the Invisible bit. In this way, options on the
machine which either are either not available or not paid for are hidden from the visualization user.
Although the layout cannot be changed in this way, certain option controls can be taken from the screen
as well as appropriate pages from the page switching system.
This allows extensive configurations to be implemented by integrating the Visual Components
visualization into the control application.
• User−Defined Input Locking
If input field password levels are not sufficient, or if status variables for visibility control are already being
used in the application, then it is easier to control input locking in the application.
If these conditions are not met, then using password levels is usually easier and less complicated when
handled and maintained in the visualization.
• User−Dependent Information Display
With its password management system for input fields, Visual Components supports the simple
administration of Write abilities (rights) in the visualization, depending on the current user level.
In some visualization applications, certain information should only be displayed to privileged users. By
default, this is not directly supported by Visual Components.
However, this behavior may now be implemented in the application with the Invisible bit which can
switch fields visible or invisible.
• Context−Sensitive Help
Using the HasFocus bit (14), the control application can determine which input field is activated (has the
input focus). This may allow an appropriate help text to be very easily displayed in a status bar or other
suitable field.
4.8.4 Advanced Text Group Options − Formatted Texts
Alarm texts and texts from text groups can be linked with so−called tags (formatted variables) and can output
strings and numeric values which are generated during runtime. Using these tags, flexible texts and texts
adjustable at runtime can be defined. However, alarm texts are limited to 4 numeric variables.
4.8.3.3 Application Possibilities 363