Working with User-defined HMI Symbols
An HMI symbol (for short: symbol) is a collection of zero or more HMI objects or other HMI symbols (that making a nested symbol) that can be re-used (instantiated) in any of your HMI pages. Usually, an HMI symbol has symbol parameters that have been defined when creating the symbol. Each symbol parameter is linked to one dynamic/action property of an object contained inside the symbol. Therefore, a symbol parameter provides access to one particular dynamic property or action of the symbol.
When inserting a symbol into an HMI page, an instance of the symbol is created. Changes made to the symbol are immediately applied to any corresponding symbol instance used in your HMI pages.
After having inserted a symbol instance into an HMI page, you have to assign each public symbol parameter to an HMI tag, HMI page or constant value. Otherwise, an error is reported in the Error List (MESSAGES window). This way, the symbol is animated based on the value of an IEC variable or the application can be operated via the HMI symbol.
| Further Info
Refer to the topic "Creating Instances of HMI Symbols / Editing Symbol Parameters" for details. |
HMI symbols can be user-defined or provided in symbol libraries. Both symbol types are organized in the COMPONENTS area under the 'HMI' category. The user-defined HMI symbols are located in the 'Local > Symbols' folder. Here, new user-defined HMI symbols can be added, structured, renamed, etc. For further information on the HMI elements available in the 'HMI' category, see the topic "HMI Objects, Symbols, Images".
| Note
PLCnext Engineer allows you to release the HMI symbols and HMI images you have created and added to your project as library. (The user-defined symbols and images are located in the 'Local' folder under the 'HMI' category). Such a released library can then be added to other PLCnext Engineer projects, thus making the contained HMI symbols and images available in the projects. For details on releasing libraries see the topic "Releasing Libraries". |
| Note
User-defined HMI symbols can be imported into the existing project from another PLCnext Engineer project using the 'File > Import from Another Project' command. The imported HMI symbols are added to the 'Local > Symbols' folder in the 'HMI' category in the COMPONENTS area. For details on the import procedure, see the topic "Importing Types (POUs, Data Types)  ‣ Importing Types from Another Project
×‣ Importing Types from PLCopen XML ×‣ Importing Types from IEC 61131-10 XML ×". |
| Note
Uniqueness of user-defined HMI symbols: A user-defined HMI symbol must only be defined once in a project. A HMI symbol with same name is, however, allowed in included libraries. This means when taking libraries into account, multiple HMI symbols with the same name are possible. |
For details on working with user-defined symbols, see the following topics: