Cognos Prompt API

Well, it’s been a week since I’ve returned from the IOD, and I’m almost fully recovered from the jet-lag. I had an absolute blast, and am looking forward to going back next year.

I promised more details on the various booths that I went to, and I do have the various papers that they gave me. I will eventually get to them! But before I do, this is what I started writing while I was at the IOD, but only now am I getting around to actually publishing it.

One of the most exciting new features in Cognos 10.2 is the introduction of a standardized prompt api. No longer will developers have to scramble to try to figure out how to get validate prompts at run time. Or how to repopulate them as needed through other interactions.

IBM has released a standard set of functions, and has even released a few samples containing them. The goal in this post is to learn how to use the new API and maybe to redo a few challenges I’ve had previously.

Just as previous version required a bit of JavaScript to prepare your page for playing with the prompt objects, this version is no different. What is different, is that instead of having to memorize the entire fW formWarpRequest nonsense, now it’s a much simpler:

var acme = {};
acme.getControl = function(promptName)
{
  var ocr = cognos.Report.getReport("_THIS_");
  return ocr.prompt.getControlByName(promptName);
};

The acme namespace is to prevent function conflicts with existing Cognos functions, just preface all functions with that and you’ll be good. The “_THIS_” will automatically be replaced with the correct Cognos Namespace, so your JavaScript should still work if you’re running the report from Report Studio or the Cognos Connection. This never ever needs to change, so just copy and paste the above (although employees of Acme Inc may want to change the fictious namespace). This solution was shamelessly ripped from Rick Blackwell’s wonderful session at the IOD. All credit for anything and everything related to Cognos and JavaScript should obviously go to him now.

To begin with, let’s use Rick’s standard example for Postal Code validation.

 	/*
	 *
	 * This function will associate a validation function with the prompt control called promptPostalCode
	 *
	 */
	asdf.assignValidator = function ( ) {
		// Create the report object
		oCR = cognos.Report.getReport( "_THIS_" );

		// Create an array of prompt controls
		// This object is used in both functions in this script.
		asdf.promptControlPostalCode = oCR.prompt.getControlByName("promptPostalCode");

		// Make sure we have a valid Postal Code in the format "ana nan" such as K3F 5F4
		asdf.promptControlPostalCode.setValidator(asdf.postalCodeValidator);

	};

	/*
	 *
	 * This function is called for each character entered by the user.
	 * Ensure the value is a valid Postal Code (ie. A1A 1A1 with spaces) using RegEx.
	 *
	 */
	asdf.postalCodeValidator = function(promptValue) {
		//promptValue is an array of 1 value

		// If a value has been entered by the user ensure it matches the pattern
		if (promptValue.length > 0) {
			var rePostalCodeFormat = new RegExp("[a-z][0-9][a-z] [0-9][a-z][0-9]", "gi" );
			if ( rePostalCodeFormat.test(promptValue[0].use) ) {
				return true;
			} else {
			    return false;
			}
		} else {
		 	// If the prompt contains no value it is valid.
			// This is important as the prompt and filter are optional
			return true;
		}
	};

His example is a bit complicated, but it’s good to demonstrate the capabilities.

The first function finds the promptPostalCode prompt, and assigns the validator. Now when a user enters a value, it will trigger the validator function, passing the entered value.
The second function will take the entered value compare it against the regex, and return a true/false, telling Cognos whether the finish button should be active, and if there should be a red underline in the prompt object.

Of course, this is not the only thing that can be done with the validator function. The validator gives us an easy to use onchange function for the prompts.

A few of my clients want tree prompts which automatically hides after a user has selects a member. Previously, there were a few was this could be accomplished, each of them more difficult than the last. But now, instead of using the JS to validate, I can use the validate function to hide the prompt after a few seconds.

First I create an HTML item containing span with an ID:

<span id="treeLabel" onclick="acme.toggleTree()">Tree Prompt</span>

Next, I wrap the tree prompt inside a span with boxtype set to none:

<span id="treePrompt" style="display:none">

</span>

First a function to directly toggle the display of the tree prompt:

acme.toggleTree = function()
{
document.getElementById('treeprompt').style.display=document.getElementById('treeprompt').style.display=='none'?'block':'none';
}

Next, the actual validation function:

/*
 * function hideTree. Paul Mendelson - 2012-10-22
 * Whenever a tree node is clicked, it will wait {acme.hideTimer} seconds before hiding
 * the tree. If another selection is made, it will restart the counter.
 */
acme.hideTree= (function () {
  var timer;
  var elm;
  return function (){
    clearTimeout(timer);
  var promptName = this.getName();

    //standard way of determing source of click.
    var targ;
    if (!e) var e = window.event;
    if(!e) return false;
    if (e.target) targ = e.target;
    else if (e.srcElement) targ = e.srcElement;
    if (targ.nodeType == 3) // defeat Safari bug
      targ = targ.parentNode;

    timer = window.setTimeout(function() {
      document.getElementById('treePrompt').style.display='none';
      document.getElementById('treeLabel').innerHTML = acme.getControl('Time').getValues()[0].display;
    },acme.hideTimer);
    return true;
    };
})();

Notice that it’s not actually doing any validation; it’s simply returning true. Notice that it’s also sending the label of the selected node to the tree label. Ultimately the new Prompt API makes it significantly easier to build complex reports.

Example XML:

<report xmlns="http://developer.cognos.com/schemas/report/9.0/" useStyleVersion="10" expressionLocale="en-us">
				<modelPath>/content/folder[@name='Samples']/folder[@name='Cubes']/package[@name='Sales and Marketing (cube)']/model[@name='2008-07-25T15:28:38.072Z']</modelPath>
				<drillBehavior modelBasedDrillThru="true"/>
				<layouts>
					<layout>
						<reportPages>
							<page name="Page1">
								<style>
									<defaultStyles>
										<defaultStyle refStyle="pg"/>
									</defaultStyles>
								</style>
								<pageBody>
									<style>
										<defaultStyles>
											<defaultStyle refStyle="pb"/>
										</defaultStyles>
									</style>
									<contents><textBox parameter="Parameter1" name="textBox" multiSelect="true"/><HTMLItem description="Label">
			<dataSource>
				<staticValue>&lt;span id="treeLabel" onclick="acme.toggleTree()"&gt;Tree Prompt&lt;/span&gt;
&lt;span id="treePrompt" style="display:none"&gt;</staticValue>
			</dataSource>
		</HTMLItem><selectWithTree parameter="Time" refQuery="Time" name="Time"><selectWithTreeItem refDataItem="Time"/></selectWithTree><HTMLItem description="scripts">
			<dataSource>
				<staticValue>&lt;/span&gt;

&lt;script&gt;

/*
 * Fictious Namespace and getter. Don't change these unless IBM says so or you know what you're doing.
 * acme is now the official standard fictious namespace (thanks Rick), so make sure all functions sit there.
 * This is based on the samples, so I'm giving all credit to Rick Blackwell of IBM.
 */
var acme = {};
acme.getControl = function(promptName)
{
  var ocr = cognos.Report.getReport("_THIS_");
  return ocr.prompt.getControlByName(promptName);
};

/*
 * Global Params
 * Paul Mendelson 2012-28-10
 * These control the behaviour of the functions below.
 */

//Time in miliseconds to wait before prompt disappears.
acme.hideTimer = 1000;

/*
 *  This will return any available methods or functions or whatever available on the referenced object.
 */
function getMethods(myObject)
{
  var funcs=[]
  for(var name in myObject)
  {
    funcs.push(name)
  }
  return  funcs.join(', ');
}

/*
 * Hide the prompt when validating
 */

/*
 * function hideTree. Paul Mendelson - 2012-10-22
 * Whenever a tree node is clicked, it will wait {acme.hideTimer} seconds before hiding
 * the tree. If another selection is made, it will restart the counter.
 */
acme.hideTree= (function () {
  var timer;
  var elm;
  return function (){
    clearTimeout(timer);
  var promptName = this.getName();

    //standard way of determing source of click.
    var targ;
    if (!e) var e = window.event;
    if(!e) return false;
    if (e.target) targ = e.target;
    else if (e.srcElement) targ = e.srcElement;
    if (targ.nodeType == 3) // defeat Safari bug
      targ = targ.parentNode;

    timer = window.setTimeout(function() {
      document.getElementById('treePrompt').style.display='none';
      document.getElementById('treeLabel').innerHTML = acme.getControl('Time').getValues()[0].display;
    },acme.hideTimer);
    return true;
    };
})();

acme.toggleTree = function()
{
  document.getElementById('treeprompt').style.display=document.getElementById('treeprompt').style.display=='none'?'block':'none'
}

/*acme.checkPostalCode = function()
{
  var rePostalCodeFormat = new RegExp( "[a-z][0-9][a-z] [0-9][a-z][0-9]", "gi" );
  if(rePostalCodeFormat.test(this.getValue())) return true;
  return false;
}
*/
acme.checkPostalCode = function()
{
  var rePostalCodeFormat = new RegExp( '^[0-9]{0,3}$', "gi" );
  if(rePostalCodeFormat.test(this.getValue())) return true;
  return false;
}
acme.getControl('textBox').setValidator(acme.checkPostalCode);
acme.getControl('Time').setValidator(acme.hideTree);
&lt;/script&gt;

</staticValue>
			</dataSource>
		</HTMLItem></contents>
								</pageBody>
							</page>
						</reportPages>
					</layout>
				</layouts>
			<XMLAttributes><XMLAttribute name="RS_CreateExtendedDataItems" value="false" output="no"/><XMLAttribute name="listSeparator" value="," output="no"/><XMLAttribute name="RS_modelModificationTime" value="2008-07-25T15:28:38.133Z" output="no"/></XMLAttributes><queries><query name="Time"><source><model/></source><selection><dataItem name="Time" aggregate="none"><expression>rootMembers([sales_and_marketing].[Time].[Time])</expression></dataItem></selection></query></queries><reportName>Paul - Tree prompt</reportName></report>