Writing client-side scripts

If you want to provide additional processing of newly entered data or have more control over user interactions with the data, you can choose to enable events in the Web DataWindow client control. To do so, you set the Client Events property on the Web Generation page in the DataWindow painter or call the SetWeight method in a server-side script.

The client control supports several events:

Most of these events have similar arguments and the same return codes as the events of the PowerBuilder DataWindow control. For information, see the DataWindow Reference or online Help.

To write a script for an event of the client control, you define a function whose name is the control name plus the event name, separated by an underscore:

HTMLGenObjectName_eventname ( arguments )

The control name is the one you specified using the SetHTMLObjectName method or the Object Name property on the Web Generation page in the DataWindow painter. The script must be enclosed in SCRIPT tags. You can include client methods in the script if client scripting is enabled (described next).

This example prevents focus from changing if the user tries to go back to an earlier row. In this case the name of the DataWindow control is dwMine:

<SCRIPT Language=JavaScript>

function dwMine_RowFocusChanging(curRow, newRow)

{

		if (newRow < curRow) { return 1; }

}

</SCRIPT>

You can put the script anywhere in your Web page template.

To write scripts that call methods of the client control, you must enable client scripting. To do so, you can set the Client Scriptable property in the DataWindow painter or call the SetWeight method in a server-side script.

Several client methods accomplish the same tasks as actions of Button controls. If your DataWindow object uses Button controls to implement scrolling and updating, you might not need to do any client scripting.

You can use the following methods on the client (methods marked with an asterisk force the Web page to be reloaded):

For information about these methods, see the DataWindow Reference or online Help.

This example includes a form with a button that causes data to be updated on the server:

<FORM NAME="update">

<INPUT type="button" value="Update" onClick="{dwMine.Update();}">

Note that you can get the same functionality with the Update action for a Button control in the DataWindow object.

If you have multiple updatable Web DataWindows on the same Web page, you can script the OnSubmit client-side event to synchronize them before the changes on the page are submitted. You call the GetFullContext method to get a string that represents the context of the client side control that would be passed on a submit, and transfer the context to the other DataWindow control.

To enable the second DataWindow to create the required fields on the submit form, each of the DataWindows must have two arguments defined as self-link arguments:

dw_1.SetSelfLink(document.name,

		 "dw_2_context=''|dw_2_action=''")

dw_2.SetSelfLink(document.name,

		 "dw_1_context=''|dw_1_action=''")

This client-side script transfers the context and action from dw_2 to dw_1 when dw_1 is submitted, and from dw_1 to dw_2 when dw_2 is submitted:

<SCRIPT>

	function dw_1_OnSubmit()

	{

		dw_1.submitForm.dw_2_context.value =

			dw_2.GetFullContext();

		dw_1.submitForm.dw_2_action.value = "";

	}

	function dw_2_OnSubmit()

	{

		dw_2.submitForm.dw_1_context.value =		

			dw_1.GetFullContext();

		dw_2.submitForm.dw_1_action.value = "";

	}

</SCRIPT>