1. WaveMaker Visual AJAX Studio 4.0 Training Basics: LiveVariables

2. 2 How it Works ● When you create a LiveVariable, you select a LiveView or LiveTable to base it on ● You must also select a database operation for the LiveVariable: Read, Insert, Update or Delete ● When you create a LiveForm or a DataGrid, you select a LiveVariable to use as the data set

3. 3 Bind Components to Data Source ● LiveVariable forms the link between the data source and the LiveForm or DataGrid

4. 4 Create a New LiveVariable ● On the Component Tree menu, click New LiveVariable icon ● Properties for the new LiveVariable now appear in the Property Editor

5. 5 Name the New LiveVariable ● Type in a name for the name property in the Property Editor ● This is the name that appears in the Component Tree and in the Binding dialogs so make the name descriptive –Studio gives the LiveVariable a default name, so this step is optional, but recommended

6. 6 Choose a Data Source ● Select a data source from the drop- down menu for the liveSource property ● This list includes all the LiveTables and LiveViews defined in the project

7. 7 LiveTables or LiveViews? ● When you create a LiveVariable, you must choose a LiveTable or a LiveView as the “source” for the data ● Choose a LiveView when: –You need to access fields from a related table or –Your LiveTable has a composite primary key ● Otherwise, use a LiveTable

8. 8 Choose a Data Operation ● Select a data operation from the drop-down menu for the operation property ● This list includes the following database operations: –readData –insertData –updateData –deleteData

9. 9 Filter the Data (optional) ● You can filter the data in the specified by the liveSource: –specify a filter object –filter individual fields ● You can only set up filters when the LiveVariable operation is readData ● Filter can be bound to a widget, expression, or service variable

10. 10 Filter the liveSource as a Whole ● Use the filter property in the Properties Tree ● Bind to an object of the same type as the LiveVariable

11. 11 Filter individual Fields ● Select a filter object in the Properties Tree ● Individual fields appear in the Property Editor

12. 12 Bind to the Field ● You can bind a filter to one or more fields ● Fields marked with an asterisk are complex structures –Bind the whole structure to an object of the same type or –Expand the structure in the Properties Tree and bind to individual fields

13. 13 Other LiveVariable Properties ● autoUpdate: automatically refresh data from database ● ignoreCaseChoose: whether to make the results case sensitive or not ● updateNow: update the Service Variable (use in design mode) ● queue: defines a list of Service Variables to execute, in order, after this Variable executes

14. 14 LiveVariable Properties for Lists ● firstRow: for setting up paging in conjunction with maxResults (ignored if maxResults is not set) ● maxResults: the number of records that will be returned at runtime ● designMaxResults: the number of records that will be returned when viewing data at design time. ● orderBy: specify a property to use for ordering the data (you can order in ascending or descending order)

15. 15 sourceData Property ● Use of the sourceData property is an advanced topic. It is not needed in most cases.

16. 16 Questions?

17. 17 Exercises 8 ● Add a Live Variable –Bind to DataGrid –Filter based on Search Criteria