A query involving a temp-table or database table (which can be a join query)
A ProDataSet object
A Buffer object
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PUBLIC BindingSource ( INPUT query-hdl AS HANDLE )
PUBLIC BindingSource ( INPUT query-hdl AS HANDLE, INPUT include-fields AS CHARACTER, INPUT except-fields AS CHARACTER ) PUBLIC BindingSource ( INPUT dataset-hdl AS HANDLE ) PUBLIC BindingSource ( INPUT dataset-hdl AS HANDLE, INPUT parent-buffer-name AS CHARACTER INPUT parent-buffer-hdl AS HANDLE ) PUBLIC BindingSource ( INPUT dataset-hdl AS HANDLE, INPUT include-fields AS CHARACTER, INPUT except-fields AS CHARACTER ) PUBLIC BindingSource ( INPUT dataset-hdl AS HANDLE, INPUT parent-buffer-name AS CHARACTER INPUT parent-buffer-hdl AS HANDLE , INPUT include-fields AS CHARACTER, INPUT except-fields AS CHARACTER ) PUBLIC BindingSource ( INPUT dataset-hdl AS HANDLE, INPUT report-mode AS LOGICAL ) PUBLIC BindingSource ( INPUT dataset-hdl AS HANDLE, INPUT parent-buffer-name AS CHARACTER INPUT parent-buffer-hdl AS HANDLE , INPUT include-fields AS CHARACTER, INPUT except-fields AS CHARACTER, INPUT report-mode AS LOGICAL ) PUBLIC BindingSource ( INPUT buffer-hdl AS HANDLE ) PUBLIC BindingSource ( INPUT buffer-hdl AS HANDLE, INPUT include-fields AS CHARACTER, INPUT except-fields AS CHARACTER ) PUBLIC BindingSource ( ) |
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"table1.field1, table1.field2, table2.field1, table1.field3"
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The query may, or may not, be part of a ProDataSet object.
The query can be either static or dynamic.
You use a handle to access either a static or a dynamic query.
The query must be scrolling. That is, a static query must be defined with the SCROLLING keyword and a dynamic query, which defaults to scrolling, must remain that way (its FORWARD-ONLY attribute must be FALSE).
The query can be a join involving one or more tables. In this case, one row is displayed in the control for each result list entry.
The ProBindingSource takes information from the table schema definition and makes it available to the bound .NET control for headings and labels. The ProBindingSource determines headings and labels by using either the column label (if defined), the field label (if defined), or the field name from the schema.
If the .NET control does not handle sorting on its own, you can do either of the following:
Let the ProBindingSource automatically sort records in the ABL data source object by setting the AutoSort property to TRUE.
Define a trigger to handle a SortRequest event.
The ProBindingSource automatically changes currency in the query (as reflected by the Position property) as the selected row in the bound .NET control changes.
The ProDataSet object can contain one or more parent and child buffers (and a set of data relations describing the relationship between the parent and child buffers).
The ProDataSet object can be either static or dynamic.
You use a handle to access either a static or dynamic ProDataSet object.
You can identify a temp-table in a ProDataSet object by either its name or its handle.
To bind a hierarchy of parent and child buffers to a single .NET control, specify a parent buffer from the ProDataSet object as the top-level table to display in the .NET control. A parent buffer is typically a top-level buffer in the ProDataSet object, but it need not be. Any child buffers of the specified parent buffer are automatically included in the hierarchy. The ProBindingSource makes a buffer's data available to a bound .NET control as follows:
If you specify a parent buffer that is a top-level buffer, the ProBindingSource uses the buffer's top-level navigation query (specified by the TOP-NAV-QUERY attribute) to populate the primary set of records, and uses the data-relation queries associated with each of the child buffers for subsequent levels.
If you specify a parent buffer that is not a top-level buffer, the ProBindingSource uses the buffer's data-relation query to populate the primary set of records, and uses the data-relation queries associated with each of the child buffers for subsequent levels.
If you specify a buffer that is not a parent buffer (that is, a buffer that has no child buffers), the ProBindingSource binds to a single table. You can achieve this same result by binding to the buffer's top-level navigation query (specified by the TOP-NAV-QUERY attribute) or its data-relation query.
If you do not specify any buffer, the ProBindingSource binds to the first top-level buffer in the ProDataSet object. The first top-level buffer is based on the order in which the buffers were defined or added in the ProDataSet object, and it matches the result from GET-TOP-BUFFER(1).
To display both parent and child buffers within the same .NET control, use a single ProBindingSource instance bound to the ProDataSet object. To display the parent and child buffers in separate .NET controls, use separate ProBindingSource instances bound to their respective queries.
The ProBindingSource automatically changes currency in the parent buffer (as reflected by the Position property) as the selected parent or child row in the bound .NET control changes.
When the user first expands (not selects) a parent row in the bound .NET control, all of the child rows for that parent row are displayed. The ProBindingSource uses the ProDataSet object's data-relation query to create and maintain a unique query for all child rows related to the expanded parent row. For example, if the user expands multiple parent rows, there will be an open child query for each expanded parent row based on the corresponding parent record.
The ProBindingSource takes information from the ProDataSet object schema definition and makes it available to the bound .NET control for headings and labels. The ProBindingSource determines headings and labels by using either the column label (if defined), the field label (if defined), or the field name from the schema.
The buffer might (but not necessarily) be part of a ProDataSet object.
The buffer can be either static or dynamic.
You use a handle to access either a static or dynamic buffer.
Use a buffer as a data source for one or more single-value controls (such as a check box or a text box).
The Position property value will always be set to zero. Therefore, you must manage currency for the buffer by changing the record in the ABL data source object programmatically.
To limit which fields are exposed in the data source object, use the SetFields( ) method before binding to the data source object.
You must bind an unbound ProBindingSource object instance to an ABL data source object at run time by setting the ProBindingSource's Handle property to the handle of the associated ABL data source object.
When you set the ProBindingSource's Handle property, the AVM includes, by default, all fields from the ABL data source object's schema in the .NET control. (This is equivalent to specifying an asterisk (*) in the include-fields parameter when invoking a ProBindingSource constructor with parameters.) If you want to limit the available fields, you must use the ProBindingSource's SetFields( ) method before you specify the Handle property. Attempting to use the SetFields( ) method after specifying the Handle property causes the ProBindingSource to throw a .NET exception.
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Since you are working with a combination of .NET controls and ABL objects, it is important to remember that .NET control parameter and property indexes are always zero-based values and ABL indexes are always one-based values.
For information on the public class members inherited from the System.Windows.Forms.BindingSource class, refer to the .NET Framework class library.