How to multiSelect with selection manager in power bi custom visual

Instead of selecting each data-point's SelectionId, which results in the selection of the intersection of those data-points, you can try composing your own SQExpr(SemanticQuery Expression) objects that describe the selection you want to perform, and pass a SelectionId object made from these objects to the SelectionManager.

In order to do so, you can use the data.SQExprBuilder module, which contains various functions that allow you to create simple SQExpr objects(E.g. ones that represent a specific value) and more complex ones(E.g. ones that represent logical operations on provided SQExprs).

In the hope that I understood the issue you encounter correctly, I believe that the following guidelines should help you overcome it:

1. You want to select data-points that come from different categories, so you don't need to create your own simple SQExpr to represent those data-points. Instead, what you need is to obtain the SQExprs that represent those data points. As you probably know, Power BI provides a DataViewScopeIdentity object for each data-point. The DataViewScopeIdentity object has an "expr" property of the type ISQExpr, which is the SQExpr object you need. Note that since it is of type ISQExpr, you'll have to type-assert it into an SQExpr object.

So if you created two data-point objects, d1 and d2, each having a DataViewScopeIdentity property called"identity" then you'll have to write something like-

var d1SQExpr: data.SQExpr = <data.SQExpr>d1.identity.expr;
var d2SQExpr: data.SQExpr = <data.SQExpr>d2.identity.expr;

2. Then, since you want to select accodring to the union of those data-points, you should use the SQExprBuilder.or() method, as follows:

var d1_or_d2SQExpr = data.SQExprBuilder.or(d1SQExpr, d2SQExpr);

3. Create a DataViewScopeIdentity object from the newly created SQExpr:

var identity = data.createDataViewScopeIdentity(d1_or_d2SQExpr);

4. Create a SelectionId object using the newly created DataViewScopeIdentity object.

5. Select that SelectionId with the selectionManager.

Few things to note here:

1. I had to do some trial and error in order to make things work for me using this technique, and you'll probably have to do some as well.

2. The above guidelines might not be tailored exactly to your needs(since I havn't read too much of your code and have no idea what "kendo multi select" is). Therefore, I would recommend you to both check out what other functionality the SQExprBuilder module provides and look for some real-life usage examples in other visuals' source code(For example, you can see a usage example for the SQExprBuilder.between() function in the Timeline custom visual's source).