Custom Visual - Slicer with 'applyJsonFilter' API

[Anonymous]

Hello, everyone!

I am building my very first custom visual and need some help in figuring out what went wrong ... I was trying to create a slicer with 'applyJsonFilter' API. 

        msd_li.addEventListener("click", event => {

          let filterText = (event.target as HTMLElement).innerText;
          console.log(filterText);

          let src=this.dataView.categorical.categories[1].source;
          console.log(src.queryName);
          const target = {
            table: src.queryName.substr(0, src.queryName.indexOf(".")),
            column:src.displayName
          };

          console.log("Table: " + target.table + "\nColumn: " + target.column);          

          let filter = new models.AdvancedFilter(target, "And", {
            operator: "Is",
            value: filterText
          });  

          debugger;
          this.host.applyJsonFilter(filter,"general","filter",powerbi.FilterAction.merge); 
        });

However, when I clicked on the element I got an error on the last line: Cannot read property 'applyJsonFilter' of undefined. I might have missed some information but wasn't able to figure out which part was wrong. 

Any help would be appreciated.