When a DataWindow object includes a Button control, the button becomes an HTML or XHTML button element in the Form element for the Web DataWindow client control. The button action becomes JavaScript code for the button’s Clicked event. You do not need to write any code yourself.
You can use Button controls for:
Navigation Buttons with the PageFirst, PageLast, PageNext, and PagePrior actions let the user scroll to other rows in the result set.
Getting and editing data Buttons with Retrieve, Update, InsertRow, DeleteRow, and AppendRow actions let the user maintain data. There must be updatable columns in the DataWindow object.
These button actions are not supported and are ignored:
Cancel |
QueryClear |
Filter |
QueryMode |
Preview |
QuerySort |
PreviewWithRulers |
SaveRowsAs |
Sort |
Button actions send information back to the server, whose scripts apply the action to the DataWindow data. Then the Web page is reloaded. To complete this loop, you must set the SelfLink property for the DataWindow object so that the server knows what page to reload.
You can set this property in the DataWindow painter on the Web Generation tab in the DataWindow properties view, or you can set it in a server-side script. The value is the name of the application server template or file to be reloaded—generally, the name of the current document. If the DataWindow uses retrieval arguments, they must be provided in the SelfLinkArgs property.
For more information, see “Passing page-specific data to the reloaded page” and the SetSelfLink method in the DataWindow Reference.
The picture on a button in a DataWindow object can be rendered in the Web browser as a JPEG, GIF, or BMP image. Use a JPEG or GIF image to ensure that the image will display on all browsers. PowerBuilder provides GIF images for commonly used buttons such as Retrieve, Update, PageNext, and so on. These pictures are included in the DWACTION.JAR file in the Sybase\Shared\PowerBuilder directory.
To make the images available to the Web page in the Web browser, you must uncompress the JAR file, deploy the image files to the page server, and set the HTMLGen.ResourceBase property to the directory where the files are located.
If you want to use an existing DataWindow object that does not have Button controls, you can edit the DataWindow object and save a new version with Button controls. However, if you are sharing DataWindow objects with an existing application and it is not practical to edit them, your Web page can include HTML or XHTML buttons that call methods of the Web DataWindow client control.
There are methods of the client control that correspond to each of the supported button actions. For information, see “Writing client-side scripts”.
You can use any image types the browser supports, most commonly JPEG or GIF. Use relative paths for ease of deployment.
To make sure the images are available to the Web page in the browser, place the image files in a directory on the Web server and then set the HTMLGen.ResourceBase property to that directory. You can do this in the DataWindow painter on the JavaScript Generation page of the DataWindow property view, or in a script:
dwMine.Modify("DataWindow.HTMLGen.ResourceBase=
'C:\Sybase\MyApp\Images'")
The ResourceBase property also specifies the location of JavaScript include files. See “Using JavaScript caching for Web DataWindow methods”.
