dbflatcheckbox.pas

(***FlatStyle v4.42.8.0 for DELPHI7 by comerose update***)2007.04.30 更新说明1.修正 TFlatListView 标题的平面显示(

  FDataLink.Control := Self;
  FDataLink.OnDataChange := DataChange;
  FDataLink.OnUpdateData := UpdateData;
  FDataLink.OnEditingChange := EditingChange;
  FPaintControl := TPaintControl.Create(Self, 'COMBOBOX');
end;

destructor TDBComboBox.Destroy;
begin
  FPaintControl.Free;
  FDataLink.Free;
  FDataLink := nil;
  inherited Destroy;
end;

procedure TDBComboBox.Loaded;
begin
  inherited Loaded;
  if (csDesigning in ComponentState) then DataChange(Self);
end;

procedure TDBComboBox.Notification(AComponent: TComponent;
  Operation: TOperation);
begin
  inherited Notification(AComponent, Operation);
  if (Operation = opRemove) and (FDataLink <> nil) and
    (AComponent = DataSource) then DataSource := nil;
end;

procedure TDBComboBox.CreateWnd;
begin
  inherited CreateWnd;
  SetEditReadOnly;
end;

procedure TDBComboBox.DataChange(Sender: TObject);
begin
  if not (Style = csSimple) and DroppedDown then Exit;
  if FDataLink.Field <> nil then
    SetComboText(FDataLink.Field.Text)
  else
    if csDesigning in ComponentState then
      SetComboText(Name)
    else
      SetComboText('');
end;

procedure TDBComboBox.UpdateData(Sender: TObject);
begin
  FDataLink.Field.Text := GetComboText;
end;

procedure TDBComboBox.SetComboText(const Value: string);
var
  I: Integer;
  Redraw: Boolean;
begin
  if Value <> GetComboText then
  begin
    if Style <> csDropDown then
    begin
      Redraw := (Style <> csSimple) and HandleAllocated;
      if Redraw then SendMessage(Handle, WM_SETREDRAW, 0, 0);
      try
        if Value = '' then I := -1 else I := Items.IndexOf(Value);
        ItemIndex := I;
      finally
        if Redraw then
        begin
          SendMessage(Handle, WM_SETREDRAW, 1, 0);
          Invalidate;
        end;
      end;
      if I >= 0 then Exit;
    end;
    if Style in [csDropDown, csSimple] then Text := Value;
  end;
end;

function TDBComboBox.GetComboText: string;
var
  I: Integer;
begin
  if Style in [csDropDown, csSimple] then Result := Text else
  begin
    I := ItemIndex;
    if I < 0 then Result := '' else Result := Items[I];
  end;
end;

procedure TDBComboBox.Change;
begin
  FDataLink.Edit;
  inherited Change;
  FDataLink.Modified;
end;

procedure TDBComboBox.Click;
begin
  FDataLink.Edit;
  inherited Click;
  FDataLink.Modified;
end;

procedure TDBComboBox.DropDown;
begin
  inherited DropDown;
end;

function TDBComboBox.GetDataSource: TDataSource;
begin
  Result := FDataLink.DataSource;
end;

procedure TDBComboBox.SetDataSource(Value: TDataSource);
begin
  if not (FDataLink.DataSourceFixed and (csLoading in ComponentState)) then
    FDataLink.DataSource := Value;
  if Value <> nil then Value.FreeNotification(Self);
end;

function TDBComboBox.GetDataField: string;
begin
  Result := FDataLink.FieldName;
end;

procedure TDBComboBox.SetDataField(const Value: string);
begin
  FDataLink.FieldName := Value;
end;

function TDBComboBox.GetReadOnly: Boolean;
begin
  Result := FDataLink.ReadOnly;
end;

procedure TDBComboBox.SetReadOnly(Value: Boolean);
begin
  FDataLink.ReadOnly := Value;
end;

function TDBComboBox.GetField: TField;
begin
  Result := FDataLink.Field;
end;

procedure TDBComboBox.KeyDown(var Key: Word; Shift: TShiftState);
begin
  inherited KeyDown(Key, Shift);
  if Key in [VK_BACK, VK_DELETE, VK_UP, VK_DOWN, 32..255] then
  begin
    if not FDataLink.Edit and (Key in [VK_UP, VK_DOWN]) then
      Key := 0;
  end;
end;

procedure TDBComboBox.KeyPress(var Key: Char);
begin
  inherited KeyPress(Key);
  if (Key in [#32..#255]) and (FDataLink.Field <> nil) and
    not FDataLink.Field.IsValidChar(Key) then
  begin
    MessageBeep(0);
    Key := #0;
  end;
  case Key of
    ^H, ^V, ^X, #32..#255:
      FDataLink.Edit;
    #27:
      begin
        FDataLink.Reset;
        SelectAll;
      end;
  end;
end;

procedure TDBComboBox.EditingChange(Sender: TObject);
begin
  SetEditReadOnly;
end;

procedure TDBComboBox.SetEditReadOnly;
begin
  if (Style in [csDropDown, csSimple]) and HandleAllocated then
    SendMessage(EditHandle, EM_SETREADONLY, Ord(not FDataLink.Editing), 0);
end;

procedure TDBComboBox.WndProc(var Message: TMessage);
begin
  if not (csDesigning in ComponentState) then
    case Message.Msg of
      WM_COMMAND:
        if TWMCommand(Message).NotifyCode = CBN_SELCHANGE then
          if not FDataLink.Edit then
          begin
            if Style <> csSimple then
              PostMessage(Handle, CB_SHOWDROPDOWN, 0, 0);
            Exit;
          end;
      CB_SHOWDROPDOWN:
        if Message.WParam <> 0 then FDataLink.Edit else
          if not FDataLink.Editing then DataChange(Self); {Restore text}
      WM_CREATE,
      WM_WINDOWPOSCHANGED,
      CM_FONTCHANGED:
        FPaintControl.DestroyHandle;
    end;
  inherited WndProc(Message);
end;

procedure TDBComboBox.ComboWndProc(var Message: TMessage; ComboWnd: HWnd;
  ComboProc: Pointer);
begin
  if not (csDesigning in ComponentState) then
    case Message.Msg of
      WM_LBUTTONDOWN:
        if (Style = csSimple) and (ComboWnd <> EditHandle) then
          if not FDataLink.Edit then Exit;
    end;
  inherited ComboWndProc(Message, ComboWnd, ComboProc);
end;

procedure TDBComboBox.CMEnter(var Message: TCMEnter);
begin
  inherited;
  if SysLocale.FarEast and FDataLink.CanModify then
    SendMessage(EditHandle, EM_SETREADONLY, Ord(False), 0);
end;

procedure TDBComboBox.CMExit(var Message: TCMExit);
begin
  try
    FDataLink.UpdateRecord;
  except
    SelectAll;
    SetFocus;
    raise;
  end;
  inherited;
end;

procedure TDBComboBox.WMPaint(var Message: TWMPaint);
var
  S: string;
  R: TRect;
  P: TPoint;
  Child: HWND;
begin
  if csPaintCopy in ControlState then
  begin
    if FDataLink.Field <> nil then S := FDataLink.Field.Text else S := '';
    if Style = csDropDown then
    begin
      SendMessage(FPaintControl.Handle, WM_SETTEXT, 0, Longint(PChar(S)));
      SendMessage(FPaintControl.Handle, WM_PAINT, Message.DC, 0);
      Child := GetWindow(FPaintControl.Handle, GW_CHILD);
      if Child <> 0 then
      begin
        Windows.GetClientRect(Child, R);
        Windows.MapWindowPoints(Child, FPaintControl.Handle, R.TopLeft, 2);
        GetWindowOrgEx(Message.DC, P);
        SetWindowOrgEx(Message.DC, P.X - R.Left, P.Y - R.Top, nil);
        IntersectClipRect(Message.DC, 0, 0, R.Right - R.Left, R.Bottom - R.Top);
        SendMessage(Child, WM_PAINT, Message.DC, 0);
      end;
    end else
    begin
      SendMessage(FPaintControl.Handle, CB_RESETCONTENT, 0, 0);
      if Items.IndexOf(S) <> -1 then
      begin
        SendMessage(FPaintControl.Handle, CB_ADDSTRING, 0, Longint(PChar(S)));
        SendMessage(FPaintControl.Handle, CB_SETCURSEL, 0, 0);
      end;
      SendMessage(FPaintControl.Handle, WM_PAINT, Message.DC, 0);
    end;
  end else
    inherited;
end;

procedure TDBComboBox.SetItems(Value: TStrings);
begin
  Items.Assign(Value);
  DataChange(Self);
end;

procedure TDBCombobox.SetStyle(Value: TComboboxStyle);
begin
  if (Value = csSimple) and Assigned(FDatalink) and FDatalink.DatasourceFixed then
    DatabaseError(SNotReplicatable);
  inherited SetStyle(Value);
end;

function TDBComboBox.UseRightToLeftAlignment: Boolean;
begin
  Result := DBUseRightToLeftAlignment(Self, Field);
end;

procedure TDBCombobox.CMGetDatalink(var Message: TMessage);
begin
  Message.Result := Integer(FDataLink);
end;

function TDBComboBox.ExecuteAction(Action: TBasicAction): Boolean;
begin
  Result := inherited ExecuteAction(Action) or (FDataLink <> nil) and
    FDataLink.ExecuteAction(Action);
end;

function TDBComboBox.UpdateAction(Action: TBasicAction): Boolean;
begin
  Result := inherited UpdateAction(Action) or (FDataLink <> nil) and
    FDataLink.UpdateAction(Action);
end;

procedure Register;
begin
  RegisterComponents('FlatStyle', [TDbFlatCheckBox]);
end;

end.