delphi - 框架内的焦点控制

Question

我希望我能解释一下我正在尝试解决的问题。我有一个包含 3 个面板的表单:1 个用于按钮，1 个用于数据，1 个用于消息。数据面板填充了一些框架(一个用于我需要使用的每个数据库表)。表格详细信息框架和另一个用于在网格中显示记录的框架是通过界面进行操作的。

这里是网格框架:

unit FraEdtList;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
  Vcl.Grids, Vcl.DBGrids;

type
  TFraEdtLst = class(TFrame)
    grdEditori: TDBGrid;
  private
    { Private declarations }
  public
    { Public declarations }
  end;

implementation

{$R *.dfm}

uses database;

end. 

这里是详细框架:

unit FraEdtDetail;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
  Vcl.StdCtrls, Vcl.Mask, Vcl.DBCtrls;

type
  TFraEdtDtl = class(TFrame)
    lblIdEditore: TLabel;
    edtIdEditore: TDBEdit;
    lblDscEditore: TLabel;
    edtDscEditore: TDBEdit;
  private
    { Private declarations }
  public
    { Public declarations }
  end;

implementation

{$R *.dfm}

uses database;

{ TFraEdtDtl }


{ TFraEdtDtl }

end.

这是接口(interface)单元:

unit Editori;

interface

uses
  FraEdtList, FraEdtDetail;

type
  IEditori = interface
    procedure CreateFraEdtLst();
    procedure CreateFraEdtDtl();
  end;

  TEditori = class(TInterfacedObject, IEditori)
  private
    FEdtLst: TfraEdtLst;
    FEdtDtl: TfraEdtDtl;
    procedure CreateFraEdtLst();
    procedure CreateFraEdtDtl();
  end;

implementation

{ TAutori }

uses Tabelle;

procedure TEditori.CreateFraEdtLst;
begin
  FEdtLst := FEdtLst.Create(frmTabelle);
  FEdtLst.Parent := frmTabelle.pnlDta;
end;

procedure TEditori.CreateFraEdtDtl;
begin
  FEdtDtl := TfraEdtDtl.Create(frmTabelle);
  FEdtDtl.Parent := frmTabelle.pnlDta;
end;

end.

我已将“Editori”单元添加到将使用框架的表单中。在本示例中，我没有使用网格，而仅使用了详细信息框架，当用户选择表格时，记录将显示为以下示例:

例如，第一个按钮(带有一张白纸)用于在我的数据库表中插入新记录，第二个按钮用于编辑当前显示的记录等等。

问题是，当用户单击“新建”按钮或“编辑”按钮时，我想聚焦 DBEdit 组件，但我无法找到执行此类操作的方法。

这是使用两个框架(和其他一些框架)的来源

unit Tabelle;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
  Vcl.ExtCtrls, RzPanel, dxBevel, Vcl.Buttons, PngSpeedButton, Autori,
  Editori, DBInterface, DbImplementation, MSAccess;

type
  TfrmTabelle = class(TForm)
    pnlCmd: TRzPanel;
    pnlDta: TRzPanel;
    pnlMsg: TRzPanel;
    bvlCmd: TdxBevel;
    bvlNav: TdxBevel;
    btnNew: TPngSpeedButton;
    btnEdit: TPngSpeedButton;
    btnSave: TPngSpeedButton;
    btnDelete: TPngSpeedButton;
    btnUndo: TPngSpeedButton;
    btnPrior: TPngSpeedButton;
    btnNext: TPngSpeedButton;
    procedure FormCreate(Sender: TObject);
    procedure btnNewClick(Sender: TObject);
    procedure btnSaveClick(Sender: TObject);
    procedure btnPriorClick(Sender: TObject);
    procedure btnNextClick(Sender: TObject);
    procedure btnEditClick(Sender: TObject);
    procedure btnDeleteClick(Sender: TObject);
    procedure btnUndoClick(Sender: TObject);
  private
    FDBTable: IDBTable;
    FAutori: IAutori;
    FEditori: IEditori;
  public
    procedure SetButtonsStatus(stsNew, stsEdit, stsSave, stsDelete, stsUndo, stsPnlDta: Boolean);
    procedure SetTableName(Table: TMSTable);
  end;

var
  frmTabelle: TfrmTabelle;

implementation

{$R *.dfm}

{ TfrmTabelle }

{ Inizializzazione }
procedure TfrmTabelle.FormCreate(Sender: TObject);
begin
  FDBTable := TDBtable.Create;
end;

{ Impostazione tabella di lavoro }
procedure TfrmTabelle.SetTableName(Table: TMSTable);
begin
  FDBTable.DBTable := Table;
  SetButtonsStatus(True, True, False, True, False, False);

  // Tabella autori
  if Table.TableName = 'Autori' then begin
    if not Assigned(FAutori) then begin
      FAutori := TAutori.Create;
      FAutori.CreateFraAutDtl;
    end;
  end;

  // Tabella editori
  if Table.TableName = 'Editori' then begin
    if not Assigned(FEditori) then begin
      FEditori := TEditori.Create;
      FEditori.CreateFraEdtDtl;
    end;
  end;

end;

{ Impostazione pulsanti }
procedure TfrmTabelle.SetButtonsStatus(stsNew, stsEdit, stsSave, stsDelete, stsUndo, stsPnlDta: Boolean);
var
  flgTblEmpty: Boolean;
begin
  flgTblEmpty := FDBTable.TableIsEmpty;
  btnNew.Enabled := stsNew;
  btnEdit.Enabled := stsEdit and not flgTblEmpty;
  btnSave.Enabled := stsSave;
  btnDelete.Enabled := stsDelete and not flgTblEmpty;
  btnUndo.Enabled := stsUndo;
  pnlDta.Enabled := stsPnlDta;
end;

{ Inserimento nuovo record }
procedure TfrmTabelle.btnNewClick(Sender: TObject);

begin
  if FDBTable.NewRecord then
    SetButtonsStatus(False, False, True, False, True, True);
end;

{ Editazione record }
procedure TfrmTabelle.btnEditClick(Sender: TObject);
begin
  if FDBTable.EditRecord then
    SetButtonsStatus(False, False, True, False, True, True);
end;

{ Salvataggio record }
procedure TfrmTabelle.btnSaveClick(Sender: TObject);
begin
  if FDBTable.SaveRecord then
    SetButtonsStatus(True, True, False, True, False, False);
end;

{ Cancellazione record }
procedure TfrmTabelle.btnDeleteClick(Sender: TObject);
begin
  if FDBTable.DeleteRecord then
    SetButtonsStatus(True, True, False, True, False, False);
end;

{ Annulla l'operazione in corso }
procedure TfrmTabelle.btnUndoClick(Sender: TObject);
begin
  if FDBTable.UndoRecord then
    SetButtonsStatus(True, True, False, True, False, False);
end;



{ Record precedente }
procedure TfrmTabelle.btnPriorClick(Sender: TObject);
begin
  if FDBTable.PriorRecord then
    SetButtonsStatus(True, True, False, True, False, False);
end;

{ Record successivo }
procedure TfrmTabelle.btnNextClick(Sender: TObject);
begin
  FDBTable.NextRecord;
end;

end.

正如您在上面的代码中看到的，数据库也是通过接口(interface)使用的!我希望我的解释很清楚，但我知道这个问题说起来有点复杂。请有人帮助我吗？

Answer 1

例如，要在用户单击 btnEdit 时将焦点集中到 edtIdEditore，请执行以下操作:

{ Editazione record }
procedure TfrmTabelle.btnEditClick(Sender: TObject);
begin
  if FDBTable.EditRecord then
    SetButtonsStatus(False, False, True, False, True, True);
  frmTabelle.edtIdEditore.SetFocus;
end;

或者将 frmTabelle 替换为单元的 var 部分中公开的表单实例的名称，然后将该单元添加到您的 uses 子句中你就完成了。