TTreeview 选择项目和级别？

Question

我有一个 TTreeView

我添加了两个级别的项目

Test 1 Parent  
  Test 1 Child  
Test 2 Parent  
  Test 2 Child A  
  Test 2 Child B  
  Test 2 Child C  

我试图根据所选级别启用和禁用“添加”、“编辑”和“删除”按钮

示例：

procedure TfrmMain.UpdateBtns;  
begin  
btnEditParent.Enabled:= (treeview.Focused ) AND (treeview.Selected <> nil);     btnDeleteParent.Enabled:= (treeview.Focused ) AND (treeview.Selected <> nil);  
btnAddChild.Enabled:= (treeview.Focused ) AND (treeview.Selected <> nil);  
btnEditChild.Enabled:= (treeview.Focused ) AND (treeview.Selected <> nil);  
btnDeleteChild.Enabled:= (treeview.Focused ) AND (treeview.Selected <> nil);  
end;  

我如何考虑这些级别？

Answer 1

TTreeNode 对象有一个 Level 属性

var
 Node : TTreeNode;
begin
 Node:=TreeView1.Selected;
 //Node.Level //The first Level is 0

end;

你可以用这种方式重写你的代码

    var
     Node : TTreeNode;
    begin
     Node:=TreeView.Selected;
     if Node<>nil then
     begin
      btnEditParent.Enabled  := (Node.Level=0);
      btnDeleteParent.Enabled:= (Node.Level=0);
      btnAddChild.Enabled    := (Node.Level=0);
      btnEditChild.Enabled   := (Node.Level>0);
      btnDeleteChild.Enabled := (Node.Level>0);
     end;
    end;