basefiltereditor.pas

Delphi数据库系统开发例子

procedure TFormBaseFilter.PopupMenuPopup(Sender: TObject);
var
  AFilter: IBaseFilter;
begin
  PopupMenu.Items.Items[0].Enabled := false;
  PopupMenu.Items.Items[1].Items[0].Enabled := false;
  PopupMenu.Items.Items[1].Items[1].Enabled := false;
  PopupMenu.Items.Items[1].Items[2].Enabled := false;
  PopupMenu.Items.Items[2].Items[0].Enabled := false;
  PopupMenu.Items.Items[2].Items[1].Enabled := false;
  If (Filters.Selected = Nil) or (Filters.Selected.Level = 0) then Abort;

  Filter.QueryInterface(IBaseFilter, AFilter);
  if HaveFilterPropertyPage(AFilter, ppDefault)       then PopupMenu.Items.Items[0].Enabled := true;
  if HaveFilterPropertyPage(AFilter, ppVFWCapFormat)  then PopupMenu.Items.Items[1].Items[0].Enabled := true;
  if HaveFilterPropertyPage(AFilter, ppVFWCapSource)  then PopupMenu.Items.Items[1].Items[1].Enabled := true;
  if HaveFilterPropertyPage(AFilter, ppVFWCapDisplay) then PopupMenu.Items.Items[1].Items[2].Enabled := true;
  if HaveFilterPropertyPage(AFilter, ppVFWCompConfig) then PopupMenu.Items.Items[2].Items[0].Enabled := true;
  if HaveFilterPropertyPage(AFilter, ppVFWCompAbout)  then PopupMenu.Items.Items[2].Items[1].Enabled := true;
  AFilter := nil;
end;

procedure TFormBaseFilter.PropertyPageClick(Sender: TObject);
var AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  ShowFilterPropertyPage(Self.Handle, AFilter, ppDefault);
  AFilter := nil;
end;

procedure TFormBaseFilter.PinMenuPopup(Sender: TObject);
begin
  If PageControl1.ActivePageIndex = 0 then
  Begin
    if Pins.ItemIndex = -1 then abort;
  End
  else
    if Pins1.ItemIndex = -1 then abort;
end;

procedure TFormBaseFilter.PinPropertyClick(Sender: TObject);
begin
  If PageControl1.ActivePageIndex = 0 then
    ShowPinPropertyPage(Self.Handle, PinList.Items[Pins.ItemIndex])
  else
    ShowPinPropertyPage(Self.Handle, PinList.Items[Pins1.ItemIndex]);
end;

procedure TFormBaseFilter.PinsSheetShow(Sender: TObject);
begin
  Pins1.Items := Pins.Items;
end;

procedure TFormBaseFilter.Pins1Click(Sender: TObject);
var
  i: integer;
  unk: IUnknown;
  EnumMT : TEnumMediaType;
begin
  PinInterfaces.Clear;
  if Pins1.ItemIndex <> -1 then
  try
    with PinList.Items[Pins1.ItemIndex] do
      for i := 0 to length(DSItfs)-1 do
        if Succeeded(QueryInterface(DSItfs[i].itf, unk)) then
          PinInterfaces.Items.Add(DSItfs[i].name);
  finally
    unk := nil;
  end;

  MediaTypes.Clear;
  if Pins1.ItemIndex <> -1 then
  begin
    EnumMT:= TEnumMediaType.Create(PinList.Items[Pins1.ItemIndex]);
    try
      if EnumMT.Count > 0 then
        for i := 0 to EnumMT.Count - 1 do
          MediaTypes.Items.Add(EnumMt.MediaDescription[i]);
    finally
      EnumMT.Free;
    end;
  end;
end;

procedure TFormBaseFilter.VFWFormatClick(Sender: TObject);
var AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  ShowFilterPropertyPage(Self.Handle, AFilter, ppVFWCapFormat);
  AFilter := nil;
end;

procedure TFormBaseFilter.VFWSourceClick(Sender: TObject);
var AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  ShowFilterPropertyPage(Self.Handle, AFilter , ppVFWCapSource);
  AFilter := nil;
end;

procedure TFormBaseFilter.VFWDisplayClick(Sender: TObject);
var AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  ShowFilterPropertyPage(Self.Handle, AFilter, ppVFWCapDisplay);
  AFilter := nil;
end;

procedure TFormBaseFilter.Config1Click(Sender: TObject);
var AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  ShowFilterPropertyPage(Self.Handle, AFilter, ppVFWCompConfig);
  AFilter := nil;
end;

procedure TFormBaseFilter.VFWAboutClick(Sender: TObject);
var AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  ShowFilterPropertyPage(Self.Handle, AFilter, ppVFWCompAbout);
  AFilter := nil;
end;

procedure TFormBaseFilter.InterfacesDblClick(Sender: TObject);
var
  AFilter: IBaseFilter;
begin
  Filter.QueryInterface(IBaseFilter, AFilter);
  if Interfaces.ItemIndex <> -1 then
  if Interfaces.Items.Strings[Interfaces.ItemIndex] = 'ISpecifyPropertyPages' then
    ShowFilterPropertyPage(Self.Handle, AFilter);
  AFilter := nil;
end;

procedure TFormBaseFilter.PinInterfacesDblClick(Sender: TObject);
begin
  if PinInterfaces.ItemIndex <> -1 then
  if PinInterfaces.Items.Strings[PinInterfaces.ItemIndex] = 'ISpecifyPropertyPages' then
    ShowPinPropertyPage(Self.Handle, PinList.Items[Pins1.ItemIndex]);
end;

procedure TFormBaseFilter.PinsDrawItem(Control: TWinControl;
  Index: Integer; Rect: TRect; State: TOwnerDrawState);
var
	Bitmap: TBitmap;      { temporary variable for the item抯 bitmap }
	Offset: Integer;      { text offset width }
begin
  with (Control as TListBox).Canvas do  { draw on control canvas, not on the form }
  begin
    Brush.Color := (Control as TListBox).Color;
    Brush.Style := bsSolid;
    FillRect(Rect);       { clear the rectangle }
    Offset := 2;          { provide default offset }
    Bitmap := TBitmap((Control as TListBox).Items.Objects[Index]);  { get the bitmap }
    if Bitmap <> nil then
    begin
      BrushCopy(Bounds(Rect.Left + Offset, Rect.Top, Bitmap.Width, Bitmap.Height),
                Bitmap, Bounds(0, 0, Bitmap.Width, Bitmap.Height), clOlive);  {render bitmap}
      Offset := Bitmap.width + 6;    { add four pixels between bitmap and text}
    end;
    If odSelected	in State then
      Brush.Color := clHighLight;
    TextOut(Rect.Left + Offset, Rect.Top, (Control as TListBox).Items[Index]);  { display the text }
    If odFocused in state then
    Begin
      Drawfocusrect(Rect);
      Drawfocusrect(Bounds(Rect.Left + Offset, Rect.Top, TextWidth((Control as TListBox).Items[Index])+1, Rect.Bottom - Rect.Top));
    End;
  end;
end;

procedure TFormBaseFilter.FiltersChange(Sender: TObject;
  Node: TTreeNode);
var
  NodeItem : pNodeItem;
  Tmp : pWidechar;
begin
  if Node = nil then Exit;
  Interfaces.Items.BeginUpdate;
  Interfaces.Items.Clear;
  Pins.Items.BeginUpdate;
  Pins.Items.Clear;
  MonikerTag.Clear;
  Try
    if Node.Level = 1 then
    begin
      NodeItem := pNodeItem(Node.Parent.Data);
      If NodeItem = nil then exit;
      SysDevEnum.SelectIndexCategory(NodeItem^.Index);
      NodeItem := pNodeItem(Node.Data);
      SysDevEnum.GetMoniker(NodeItem^.Index).GetDisplayName(nil, nil, Tmp);
      MonikerTag.Text := Tmp;
      Filter.BaseFilter.Moniker := SysDevEnum.GetMoniker(NodeItem^.Index);
      IFilter(Filter).NotifyFilter(foRefresh);
      GetFilterInfo;
    end;
  finally
    Interfaces.Items.EndUpdate;
    Pins.Items.EndUpdate;
  end;
end;

procedure TFormBaseFilter.PinsMeasureItem(Control: TWinControl;
  Index: Integer; var Height: Integer);
begin
  (Control as TListBox).Canvas.Font := (Control as TListBox).Font;
  If Height < (Control as TListBox).Canvas.TextHeight((Control as TListBox).Items[Index]) then
    Height := (Control as TListBox).Canvas.TextHeight((Control as TListBox).Items[Index]);
end;

procedure TFormBaseFilter.FiltersDblClick(Sender: TObject);
begin
  If Filters.Selected = nil then Exit;
  If Filters.Selected.Level = 1 then btok.Click;
end;

procedure TFormBaseFilter.FiltersCustomDrawItem(Sender: TCustomTreeView;
  Node: TTreeNode; State: TCustomDrawState; var DefaultDraw: Boolean);
var
  NodeItem : pNodeItem;
begin
  Filters.Canvas.Font.Color := FilterColors[0];
  if Node = nil then Exit;
  if Node.Level < 1 then exit;
  NodeItem := pNodeItem(Node.Data);
  Filters.Canvas.Font.Color := NodeItem^.Color;
end;

procedure TFormBaseFilter.InfoBtnClick(Sender: TObject);
begin
  PageControl1.ActivePageIndex := 2;
end;

end.