Question

我有一个TreeViewItem，它的onMouseUp没有被解雇，我尝试缩小我的复杂类，并且能够产生一个有效的onMouseUp实例，看来onMouseMove覆盖导致此行为是一个谜，因为我正在使用onMouseUp，但没有覆盖onMouseMove！
如何解决此代码？

unit Unit2;

interface

uses
  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
  FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FMX.Layouts,
  FMX.TreeView;

type
  TForm2 = class(TForm)
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
    procedure MouseMove(Shift: TShiftState; X, Y: Single); override;
    procedure onItemMouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Single);
  public
    { Public declarations }
  end;

var
  Form2: TForm2;

implementation

{$R *.fmx}

procedure TForm2.FormCreate(Sender: TObject);
var
  treeView: TTreeView;
  treeViewItem: TTreeViewItem;
begin
  treeView := TTreeView.Create(nil);
  treeView.Position.X := 0;
  treeView.Position.Y := 0;
  treeView.Width := 200;
  treeView.Height := 300;
  treeView.Parent := form2;

  treeViewItem := TTreeViewItem.Create(nil);
  treeViewItem.Parent := treeView;
  treeViewItem.Text := 'This is a test';
  treeViewItem.OnMouseUp := onItemMouseUp;
end;

procedure TForm2.onItemMouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X: Single; Y: Single);
begin
  ShowMessage('onItemMouseUp');
end;

procedure TForm2.MouseMove(Shift: TShiftState; X: Single; Y: Single);
begin

end;

end.

Answer 1

MouseMove(...) override;会覆盖其他所有onMouseMove，这通常用于如果您需要确保在MouseMove上执行而不管您关注的对象是什么，因为您要覆盖{{1 }}，您必须在正文中使用关键字MoveMove，这样才能确保所有其他继承的Inherited也能正常工作。
因此，您只需要将MouseMove更改为此：

onMouseMove

onMouseMove覆盖使onMouseUp无法正常工作

1 个答案: