Qlik Sense Generic Object IV: The lists

A Qlik Sense Generic Object can also be used to list objects in the Qlik Sense app to which it belongs. You can use it to list things like:

  • fields
  • dimensions
  • measures
  • bookmarks
  • snapshots
  • media (that is images controlled by Qlik Sense)
  • sheets
  • master objects
  • variables
  • stories

The javascript APIs provide the app.getList method, which is a wrapper that helps you get theses lists. It will create a session object for you with the list you are requesting, get that actual data in the list and call your callback function once the data is available.

List are live – your callbacks might be called several times

Just like with other Generic Objects the data might be invalidated. If you are using the javascript APIs it will then be automatically revalidated and your callback function will be called again, so you should be prepared that your callback might be called multiple times. But unlike the Hypercube and List Object the lists are not affected by the users selections. Instead they will be invalidated when the underlying data changes:

  • if the user adds a bookmark, you will get a new bookmarklist
  • if the user adds a measure, you will get a new measurelist
  • if the user adds a dimension, you will get a new dimensionlist
  • etc….

Configure the data you get in your list

The data you get in your lists is configurable. If you use the API method, you will get a default set of fields for each item in the list, but you can set the list up to suite your needs.

As an example, if you use the api method getList(‘measure’, callback), you will get a list where records look like this:

The first and second part, qInfo and qMeta, will always be there. They contain the id to use when refering to this measure and title and description use ful in a list of measures. The third part however, qData, is configurable. The default configuration just gives you tags and title one more time, but if you instead want more data about the measure, you can use your own measure list definition like this:

Under qData you provide your own mapping of the properties you want. In this case I have just specified that I want everything under qMeasure included. You can also specify individual fields.

And get output that includes more data for the measures:

And the same goes for the other lists, you can supply your own definitions and get more data included.

Qlik Sense Generic Object III: Listboxes

SWhile the HyperCube is the main object for calculating data the ListboxObject is a way to list available values for a field. Its the object behind the listboxes in the Filter Panel. It is also the object used for the listboxes that are created when you click on a field in the selection toolbar.

An example setup from the horizontal listbox extension example, included with the Qlik Sense installation:

This contains defaults for most of the parameters, except the actual field, which the user selects in the property panel, which looks like this:

As you can see the Listbox has either a predefined measure from the library, in which case qListObjectDef.qLibraryId will contain the id of the measure (some UID string) or it has a field name, which will be in the array qListObjectDef.qDef.qFieldDefs at the first position. You don’t really have to bother about which one the user selects to use, the ListboxObject will work the same anyhow.

Frequencies and sort order

There are also some other properties in the ListboxObject that are well known to QlikView users. The frequence mode gives you some additional info on the frequency of the respective values in the ListboxObject. Look to horizontal listbox extension for an example. There is also the qSortCriterias array, which allows you to specify the sort order. The default is to have the selected values first, but you might want to for example keep months order from January to December irrespective of which month is selected.

Mashup editor – even more properties

Like with the Hypercube, you can also build a ListboxObject in the mashup editor. The tool to do this looks like this:

As you can see, you also get the option to include expressions in your listbox, usable if you want to make some calculations for each value in the list. The mashup editor will create a ListboxObject for you like this:

The expressions are added to the ListboxObject in the qExpressions array. In this example I have used predefined measures, but you can also use measures defined in the actual listbox object. The mashup editor includes a expression editor (actually the same used in the Qlik Sense client) to help you with this.