kendodropdownlist filter json response that has field

Question

I am doing the below currently; all my JSON entries have styleName , however some have the field txt , I want to display only the styleName data that has the txt field in my dropdown list.

var dataSourceJSON = new kendo.data.DataSource({
    transport: {
        read: {
            url: dataURL,
            dataType: "json",
            type: 'GET'
        }
    }});dataSourceJSON.read();

    $("#dropdown").kendoDropDownList({
        dataSource    : dataSourceJSON,
        dataTextField : "styleName"
    });

Before using kendo, I was achieving this with the below, within a fetch on classic dropdowns. But I am unsure how to incorporate such logic with kendoDropDownList

if (data[i].txt) {
     option.text = data[i].styleName;
     dropdown.add(option);
}..../

Update , this is where I am currently at; I can console.log the correct data in my schema parse but am still having a hard time getting the filtered data into the dropdown.

  var ctemp;
  var dataSourceJSON = new kendo.data.DataSource({
    transport: {
        read: {
            url: dataURL,
            dataType: "json",
            type: 'GET'
        }
    },
    schema: {
        parse: function(datC) {
            console.log(datC);
            for (let i = 0; i < datC.length; i++) {
                if (datC[i].txt) {
                    ctemp = datC; // <-- This works and what I need
                    console.log(ctemp);
                }
            }
        }
    }
    });dataSourceJSON.read();

    $("#dropdown").kendoDropDownList({
        optionLabel: "Choose",
        dataSource    : dataSourceC,
        dataTextField : ctemp // <--- does nothing
    });

Answer 1

You can use kendo dataSource filter for this case. DataSource filter

Just check if a field is notnull and that's it.

var dataSource = new kendo.data.DataSource({
  data: [
    { styleName: "Style 1", txt: 'test' },
    { styleName: "Style 2" },
    { styleName: "Style 3", txt: 'test' },
  ],
  filter: { field: "txt", operator: "isnotnull" }
});

I made an example: Filter by field