问使用setText时出现连接IQ意外类型错误

EN

using Toybox.WatchUi as Ui;
using Toybox.System as Sys;
using Toybox.Position as Position;

class DiscGolfMenuDelegate extends Ui.MenuInputDelegate {

    var _view;

    function initialize() {
        MenuInputDelegate.initialize();
        _view = new DiscGolfView();
    }

    function onMenuItem(item) {
        if (item == :measure_throw) {
            Sys.println("item 1");
            _view.setLongestThrow("yeet");
        } else if (item == :start_game) {
            Sys.println("item 2");
        }
    }

}

function setLongestThrow(msg) {
    longest_throw_label.setText(msg);
}