Method test

tests/ListViewComponents/LayoutTest.ts:110–167

(layoutName)

        testFirstVisibleInConstructor = function (complete) {
            function test(layoutName) {
                var element = document.createElement("div");
                element.style.width = "200px";
                element.style.height = "200px";
                testRootEl.appendChild(element);

                var data = [];
                for (var i = 0; i < 100; i++) {
                    data.push({
                        label: "Item" + i
                    });
                }

                var requests = [];

                var listView = new ListView(element, {
                    itemDataSource: createDataSource(data, requests),
                    layout: new WinJS.UI[layoutName](),
                    pagesToLoad: 10,
                    itemTemplate: function (itemPromise) {
                        return itemPromise.then(function (item) {
                            var element = document.createElement("div");
                            element.style.width = "100px";
                            element.style.height = "100px";
                            element.textContent = item.data.label;
                            return element;
                        });
                    },
                    indexOfFirstVisible: 24
                });

                return new WinJS.Promise(function (complete) {
                    function checkAndExecute() {
                        if (listView.loadingState === "complete") {
                            if (layoutName.indexOf("GridLayout") == 0) {
                                LiveUnit.Assert.areEqual(1200, listView.scrollPosition);
                            }
                            else {
                                LiveUnit.Assert.areEqual(2400, listView.scrollPosition);
                            }
                            LiveUnit.Assert.areEqual(24, listView.indexOfFirstVisible);

                            LiveUnit.Assert.areEqual(-1, requests.indexOf(2));
                            LiveUnit.Assert.areEqual(-1, requests.indexOf(3));

                            var offsetFromSurface = listView._horizontal() ? Helper.ListView.offsetLeftFromSurface : Helper.ListView.offsetTopFromSurface;
                            LiveUnit.Assert.areEqual(listView.scrollPosition, offsetFromSurface(listView, Helper.ListView.containerFrom(listView.elementFromIndex(24))));

                            listView.removeEventListener("loadingstatechanged", checkAndExecute, false);
                            testRootEl.removeChild(element);
                            complete();
                        }
                    }

                    listView.addEventListener("loadingstatechanged", checkAndExecute, false);
                    checkAndExecute();
                });
            }