FireMonkey ListView 自动计算行高

说明:展示 ListView 视其每一行 Item 的 Detail 字串长度自动调整高度(可每行高度不同)。

适用:Delphi XE7 / XE8

源码下载:[原创]ListView_自动计算行高(by龟山阿卍).zip

procedure TForm1.Button1Click(Sender: TObject);
const DetailStr: array[0..2] of String =
('1234567890123456789012345678901234567890123456789012345678901234567890'
,'abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz'
,'ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ'
);
var i, r: Integer;
    Item1: TListViewItem;
begin
     for i:=0 to 100 do
     begin
          Item1 := ListView1.Items.Add;
          r := Random(3);
          Item1.Detail := DetailStr[r].Substring(0, Random(DetailStr[r].Length));
          Item1.Text := i.ToString;
     end;
end;

procedure TForm1.ListView1UpdateObjects(const Sender: TObject;
  const AItem: TListViewItem);
var R: TRectF;
begin
     if (AItem.Objects.DetailObject <> nil) and
        (AItem.Objects.DetailObject.Text <> '') then
     begin
          // 计算文字显示的区域
          R := RectF(0, 0, AItem.Objects.DetailObject.Width, 10000);
          ListView1.Canvas.MeasureText(R,
            AItem.Objects.DetailObject.Text,
            AItem.Objects.DetailObject.WordWrap,
            [], TTextAlign.Leading, TTextAlign.Leading);

          // 设定高度
          AItem.Height := Trunc(R.Height);
     end;
end;

 

补充:计算最后一项区域并卷到最后一项

procedure TForm1.Button2Click(Sender: TObject);
var R: TRectF;
begin
     R := ListView1.GetItemRect(ListView1.Items.Count - 1); // 取得最后一项的真实区域 (不等高也能计算)
     ListView1.ScrollViewPos := R.Bottom; // 卷到最后
end;

 

posted @ 2015-03-20 14:27  龟山Aone  阅读(2550)  评论(0编辑  收藏  举报