English Qlik Sense Developers 3.2

Backend API

Since:
  • 1.0

The Backend API consists of a number of methods, and is used for communicating with the Qlik engine. It provides Helper functions for Qlik engine calls and access to Qlik engine data. In short terms, the Backend API is a wrapper around selected Qlik Engine API methods but with the difference that the Backend API is aware of the context, that is the current WebSocket connection and the Qlik Sense app.

Getting started

The Backend API is available for extension developers as this.backendApi.

this.backendApi.eachDataRow(function(rownum, row) {
	.....
});

Version history

Each method and property contain information around when it was introduced, updated, deprecated or removed. A list of all relevant API changes per version release can be found in API version history.

Examples of use

Learn how to use the Backend API in your visualization extensions.

Selections

The following Backend API methods are available when you are working with selections in the generic object that is behind your extension.

  • selectValues
  • selectRange
  • clearSelections
  • hasSelections

Use the selectValues method to select values in this object. The call triggers a repaint of the object.

$element.find('li').on('qv-activate', function() {
	if(this.hasAttribute("data-value")) {
		var value = parseInt(this.getAttribute("data-value"), 10), dim = 0;
		self.backendApi.selectValues(dim, [value], true);
	}
});

The selectRange method selects values in this object using ranges.

var range = {
	"qMeasureIx": 1,
	"qRange": {
		"qMin": 10,
		"qMax": 100,
		"qMinInclEq": true,
		"qMaxInclEq": true
	}
};
self.backendApi.selectRange( [range], false);

The hasSelections method can be used to find out if there are unconfirmed selections for this object.

this.backendApi.hasSelections();

If there are unconfirmed selections for this object, you can use the clearSelections method to clear them.

this.backendApi.clearSelections();

Search

You can use the following Backend API methods when working with search in list objects.

  • search
  • acceptSearch
  • abortSearch

Use the search method to search for a term in a list object. This results in an updated layout which contains only the matching records.

this.backendApi.search("A");

The acceptSearch method accepts the search result and makes it selected in the field.

this.backendApi.acceptSearch(false);

Use the abortSearch method if the search is to be aborted. This clears the existing search and returns the object to the state it was in prior to the search.

this.backendApi.abortSearch();