StylesData
无法提供对“复杂”属性的访问。你可以做下一个解决方法:
var
Obj: TObject;
myListBoxItem: TListBoxItem;
begin
// create new item
myListBoxItem:=TListBoxItem.Create(nil);
ListBox1.AddObject(myListBoxItem);
myListBoxItem.StyleLookup:='listboxitembottomdetail';
myListBoxItem.StylesData['ellipsestyle.fill.Kind']:=TValue.From<TBrushKind>(TBrushKind.Gradient);
// access to GradientPoints collection
Obj:=myListBoxItem.StylesData['ellipsestyle.fill.Gradient.Points'].AsObject;
if not (Obj is TGradientPoints) then
Exit;
TGradientPoints(Obj).Points[0].Color:=TAlphaColorRec.Blanchedalmond;
TGradientPoints(Obj).Points[1].Color:=TAlphaColorRec.Alpha;
关于FindStyleResource
:
首先,您可以访问样式对象 -OnApplyStyleLookup
指定 ListBoxItem 的事件。之前OnApplyStyleLookup
(例如 - 在创建 Listboxitem 之后)您无法访问样式。
因此,将您的代码移至ListBoxItem.OnApplyStyleLookup
并更改如下:
procedure TForm2.ListBoxItem1ApplyStyleLookup(Sender: TObject);
var
FMXObj: TFmxObject;
Ellipse: TEllipse;
begin
if not (Sender is TFmxObject) then
Exit;
FMXObj:=TFMXObject(Sender).FindStyleResource('ellipsestyle');// get object by it`s "StyleName".
if not (FMXObj is TEllipse) then
Exit;
Ellipse:=TEllipse(FMXObj);
Ellipse.Fill.Kind:=TBrushKind.Gradient;
Ellipse.Fill.Gradient.Points.Points[0].Color:=TAlphaColorRec.Blueviolet;
Ellipse.Fill.Gradient.Points.Points[1].Color:=TAlphaColorRec.Greenyellow;
end;
此外,您可以强制加载样式(这是不推荐的方式 - 默认情况下,第一次绘画时加载的对象的样式):
var
FMXObj: TFmxObject;
Ellipse: TEllipse;
myListBoxItem: TListBoxItem;
begin
myListBoxItem:=TListBoxItem.Create(nil);
ListBox1.AddObject(myListBoxItem);
myListBoxItem.StyleLookup:='listboxitembottomdetail';
// force load style
myListBoxItem.NeedStyleLookup;
myListBoxItem.ApplyStyleLookup; // this method also call OnApplyStyleLookup event
FMXObj:=myListBoxItem.FindStyleResource('ellipsestyle');
if not (FMXObj is TEllipse) then
Exit;
Ellipse:=TEllipse(FMXObj);
Ellipse.Fill.Kind:=TBrushKind.Gradient;
Ellipse.Fill.Gradient.Points.Points[0].Color:=TAlphaColorRec.Blanchedalmond;
Ellipse.Fill.Gradient.Points.Points[1].Color:=TAlphaColorRec.Alpha;