我有一个TListView样式的vsReport,其中的组可见。这些组以创建顺序显示。但是我想做两个按钮(上下),然后将选定的组移到另一个位置(在运行时)。可能吗 ?

最佳答案

您可以通过更改组项目的Index属性来执行此操作。以下代码演示了用法:

procedure TForm1.btnMoveUpClick(Sender: TObject);
var
  itm: TListItem;
  i: Integer;
begin
  itm := ListView1.Selected;
  if Assigned(itm) then
    for i := 0 to ListView1.Groups.Count - 1 do
      if ListView1.Groups[i].GroupID = itm.GroupID then
      begin
        if ListView1.Groups[i].Index > 0 then
          ListView1.Groups[i].Index := ListView1.Groups[i].Index - 1;
        break;
      end;
end;

procedure TForm1.btnMoveDownClick(Sender: TObject);
var
  itm: TListItem;
  i: Integer;
begin
  itm := ListView1.Selected;
  if Assigned(itm) then
    for i := 0 to ListView1.Groups.Count - 1 do
      if ListView1.Groups[i].GroupID = itm.GroupID then
      begin
        if ListView1.Groups[i].Index < ListView1.Groups.Count - 1 then
          ListView1.Groups[i].Index := ListView1.Groups[i].Index + 1;
        break;
      end;
end;


脚注:当然,可以这样重构:

function GetGroupFromGroupID(AListView: TListView; AGroupID: integer): TListGroup;
var
  i: Integer;
begin
  for i := 0 to AListView.Groups.Count - 1 do
    if AListView.Groups[i].GroupID = AGroupID then
      Exit(AListView.Groups[i]);
  result := nil;
end;

procedure TForm1.btnMoveUpClick(Sender: TObject);
var
  itm: TListItem;
  grp: TListGroup;
begin
  itm := ListView1.Selected;
  if Assigned(itm) then
  begin
    grp := GetGroupFromGroupID(ListView1, itm.GroupID);
    if Assigned(grp) and (grp.Index > 0) then
      grp.Index := grp.Index - 1;
  end;
end;

procedure TForm1.btnMoveDownClick(Sender: TObject);
var
  itm: TListItem;
  grp: TListGroup;
begin
  itm := ListView1.Selected;
  if Assigned(itm) then
  begin
    grp := GetGroupFromGroupID(ListView1, itm.GroupID);
    if Assigned(grp) and (grp.Index < ListView1.Groups.Count - 1) then
      grp.Index := grp.Index + 1;
  end;
end;

关于listview - 如何更改TListGroups中的组顺序?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/50219494/

10-08 22:41
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