我正在使用virtualstringtree来获取基本树视图功能以及复选框等。
我使用了原始文档(从2006年开始),但是在加载我保存的数据时遇到错误,即使虚拟字符串树看起来没问题。
我相信我应该使用InitNode
而不是MAddVSTStructure
。
有人可以建议在这种情况下添加节点的正确方法吗? 这可能是加载过程加载信息的原因,但是在单击已加载的节点时会出现访问冲突。
type
PTreeData = ^TTreeData;
TTreeData = record
FCaption: String;
FRichText: String;
FImageIndex: integer;
FVisibility: integer;
FUniqueID: integer;
end;
function MAddVSTStructure(AVST: TCustomVirtualStringTree; ANode: PVirtualNode; ARecord: TTreeData): PVirtualNode;
var
Data: PTreeData;
begin
Result:= AVST.AddChild(ANode);
Result.CheckType:=ctTriStateCheckBox;
Data:= AVST.GetNodeData(Result);
Data^.FCaption:= ARecord.FCaption;
Data^.FRichText:= ARecord.FRichText;
Data^.FImageIndex:= ARecord.FImageIndex;
Data^.FVisibility:= ARecord.FVisibility;
Data^.FUniqueID:= ARecord.FUniqueID;
AVST.ValidateNode(Result, False);
end;
procedure vstSaveNode(Sender: TBaseVirtualTree; Node: PVirtualNode; Stream: TStream);
var
Data: PTreeData;
Len: integer;
begin
Data:= Sender.GetNodeData(Node);
//FCaption
Len:= Length(Data.FCaption);
Stream.Write(Len, SizeOf(Len));
Stream.Write(PChar(Data.FCaption)^, Len * SizeOf(Char));
//FRichText
Len:= Length(Data.FRichText);
Stream.Write(Len, SizeOf(Len));
Stream.Write(PChar(Data.FRichText)^, Len * SizeOf(Char));
//FImageIndex
Stream.Write(Data.FImageIndex, SizeOf(Data.FImageIndex));
//FVisibility
Stream.Write(Data.FVisibility, SizeOf(Data.FVisibility));
//FUniqueID
Stream.Write(Data.FUniqueID, SizeOf(Data.FUniqueID));
end;
procedure vstLoadNode(Sender: TBaseVirtualTree; Node: PVirtualNode; Stream: TStream);
var
Data: PTreeData;
Len: Integer;
begin
Data:= Sender.GetNodeData(Node);
//Len:= Length(Data.FCaption);
//FCaption
Stream.Read(Len, SizeOf(Len));
SetLength(Data.FCaption, Len);
Stream.Read(PChar(Data.FCaption)^, Len * SizeOf(Char) );
//FRichText
Stream.Read(Len, SizeOf(Len));
SetLength(Data.FRichText, Len);
Stream.Read(PChar(Data.FRichText)^, Len * SizeOf(Char));
//FImageIndex
Stream.Read(PChar(Data.FImageIndex)^, SizeOf(Data.FImageIndex));
//FVisibility
Stream.Read(PChar(Data.FVisibility)^, SizeOf(Data.FVisibility));
//FUniqueID
Stream.Read(PChar(Data.FUniqueID)^, SizeOf(Data.FUniqueID));
end;