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root/public/ibx/trunk/ibcontrols/IBLookupComboEditBox.pas
Revision: 29
Committed: Sat May 9 11:37:49 2015 UTC (8 years, 11 months ago) by tony
Content type: text/x-pascal
File size: 16261 byte(s)
Log Message:
Committing updates for Release R1-2-4

File Contents

# User Rev Content
1 tony 21 (*
2     * IBX For Lazarus (Firebird Express)
3     *
4     * The contents of this file are subject to the Initial Developer's
5     * Public License Version 1.0 (the "License"); you may not use this
6     * file except in compliance with the License. You may obtain a copy
7     * of the License here:
8     *
9     * http://www.firebirdsql.org/index.php?op=doc&id=idpl
10     *
11     * Software distributed under the License is distributed on an "AS
12     * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
13     * implied. See the License for the specific language governing rights
14     * and limitations under the License.
15     *
16     * The Initial Developer of the Original Code is Tony Whyman.
17     *
18 tony 23 * The Original Code is (C) 2015 Tony Whyman, MWA Software
19 tony 21 * (http://www.mwasoftware.co.uk).
20     *
21     * All Rights Reserved.
22     *
23     * Contributor(s): ______________________________________.
24     *
25     *)
26     unit IBLookupComboEditBox;
27    
28     {$mode objfpc}{$H+}
29    
30     interface
31    
32     uses
33     Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, DbCtrls,
34 tony 27 ExtCtrls, IBSQLParser, DB, StdCtrls, IBCustomDataSet;
35 tony 21
36     type
37    
38     {TIBLookupComboEditBox is a TDBLookupComboBox descendent that implements "autocomplete"
39     of typed in text and "autoinsert" of new entries. Autocomplete uses SQL manipulation
40     to revise the available list and restrict it to items that are prefixed by the
41     typed text (either case sensitive or case insenstive). Autoinsert allows a
42     newly typed entry to be added to the list dataset and included in the available
43     list items. }
44    
45     TAutoInsert = procedure(Sender: TObject; aText: string; var NewKeyValue: variant) of object;
46     TCanAutoInsert = procedure (Sender: TObject; aText: string; var Accept: boolean) of object;
47    
48     TIBLookupComboEditBox = class;
49    
50     { TIBLookupComboDataLink }
51    
52     TIBLookupComboDataLink = class(TDataLink)
53     private
54     FOwner: TIBLookupComboEditBox;
55     protected
56     procedure ActiveChanged; override;
57     procedure RecordChanged(Field: TField); override;
58     procedure UpdateData; override;
59     public
60     constructor Create(AOwner: TIBLookupComboEditBox);
61     end;
62    
63 tony 27 { TIBLookupControlLink }
64 tony 21
65 tony 27 TIBLookupControlLink = class(TIBControlLink)
66     private
67     FOwner: TIBLookupComboEditBox;
68     protected
69     procedure UpdateSQL(Sender: TObject); override;
70     public
71     constructor Create(AOwner: TIBLookupComboEditBox);
72     end;
73    
74    
75 tony 21 { TIBLookupComboEditBox }
76    
77     TIBLookupComboEditBox = class(TDBLookupComboBox)
78     private
79     FCanAutoInsert: TCanAutoInsert;
80     { Private declarations }
81     FDataLink: TIBLookupComboDataLink;
82 tony 27 FIBLookupControlLink: TIBLookupControlLink;
83 tony 21 FAutoComplete: boolean;
84     FAutoInsert: boolean;
85     FKeyPressInterval: integer;
86     FOnCanAutoInsert: TCanAutoInsert;
87     FRelationName: string;
88     FTimer: TTimer;
89     FFiltered: boolean;
90     FOnAutoInsert: TAutoInsert;
91     FOriginalTextValue: string;
92     FUpdating: boolean;
93     FInserting: boolean;
94     FExiting: boolean;
95     FLastKeyValue: variant;
96     procedure DoActiveChanged(Data: PtrInt);
97     function GetAutoCompleteText: TComboBoxAutoCompleteText;
98     function GetListSource: TDataSource;
99     function GetRelationNameQualifier: string;
100     procedure HandleTimer(Sender: TObject);
101 tony 27 procedure IBControlLinkChanged;
102 tony 21 procedure ResetParser;
103     procedure RecordChanged(Sender: TObject; aField: TField);
104     procedure SetAutoCompleteText(AValue: TComboBoxAutoCompleteText);
105     procedure SetListSource(AValue: TDataSource);
106     procedure UpdateList;
107     procedure UpdateSQL(Sender: TObject; Parser: TSelectSQLParser);
108     procedure HandleEnter(Data: PtrInt);
109     procedure UpdateLinkData(Sender: TObject);
110     protected
111     { Protected declarations }
112     procedure ActiveChanged(Sender: TObject);
113     procedure CheckAndInsert;
114     procedure DoEnter; override;
115     procedure DoExit; override;
116     procedure KeyUp(var Key: Word; Shift: TShiftState); override;
117 tony 29 procedure Loaded; override;
118 tony 27 procedure Notification(AComponent: TComponent; Operation: TOperation); override;
119 tony 21 procedure SetItemIndex(const Val: integer); override;
120 tony 27 function SQLSafe(aText: string): string;
121 tony 21 procedure UpdateShowing; override;
122 tony 27
123 tony 21 public
124     { Public declarations }
125     constructor Create(TheComponent: TComponent); override;
126     destructor Destroy; override;
127     procedure EditingDone; override;
128     published
129     { Published declarations }
130     property AutoInsert: boolean read FAutoInsert write FAutoInsert;
131     property AutoComplete: boolean read FAutoComplete write FAutoComplete default true;
132     property AutoCompleteText: TComboBoxAutoCompleteText read GetAutoCompleteText
133     write SetAutoCompleteText;
134     property ItemHeight;
135     property ItemWidth;
136     property ListSource: TDataSource read GetListSource write SetListSource;
137 tony 27 property KeyPressInterval: integer read FKeyPressInterval write FKeyPressInterval default 200;
138 tony 21 property RelationName: string read FRelationName write FRelationName;
139     property OnAutoInsert: TAutoInsert read FOnAutoInsert write FOnAutoInsert;
140     property OnCanAutoInsert: TCanAutoInsert read FOnCanAutoInsert write FOnCanAutoInsert;
141     end;
142    
143    
144     implementation
145    
146 tony 27 uses IBQuery, LCLType, Variants, LCLProc;
147 tony 21
148 tony 27 { TIBLookupControlLink }
149 tony 21
150 tony 27 constructor TIBLookupControlLink.Create(AOwner: TIBLookupComboEditBox);
151 tony 21 begin
152 tony 27 inherited Create;
153     FOwner := AOwner;
154 tony 21 end;
155    
156 tony 27 procedure TIBLookupControlLink.UpdateSQL(Sender: TObject);
157 tony 21 begin
158 tony 27 FOwner.UpdateSQL(self,TIBParserDataSet(Sender).Parser)
159     end;
160 tony 21
161 tony 27 { TIBLookupComboDataLink }
162    
163     procedure TIBLookupComboDataLink.ActiveChanged;
164     begin
165     FOwner.ActiveChanged(self)
166 tony 21 end;
167    
168     procedure TIBLookupComboDataLink.RecordChanged(Field: TField);
169     begin
170     FOwner.RecordChanged(self,Field);
171     end;
172    
173     procedure TIBLookupComboDataLink.UpdateData;
174     begin
175     FOwner.UpdateLinkData(self)
176     end;
177    
178     constructor TIBLookupComboDataLink.Create(AOwner: TIBLookupComboEditBox);
179     begin
180     inherited Create;
181     FOwner := AOwner
182     end;
183    
184     { TIBLookupComboEditBox }
185    
186     procedure TIBLookupComboEditBox.HandleTimer(Sender: TObject);
187     var ActiveState: boolean;
188     begin
189     FTimer.Interval := 0;
190     FFiltered := Text <> '';
191     UpdateList
192     end;
193    
194 tony 27 procedure TIBLookupComboEditBox.IBControlLinkChanged;
195     begin
196     if (ListSource <> nil) and (ListSource.DataSet <> nil) and (ListSource.DataSet is TIBParserDataSet) then
197     FIBLookupControlLink.IBDataSet := TIBCustomDataSet(ListSource.DataSet)
198     else
199     FIBLookupControlLink.IBDataSet := nil;
200     end;
201    
202 tony 21 function TIBLookupComboEditBox.GetListSource: TDataSource;
203     begin
204     Result := inherited ListSource;
205     end;
206    
207     function TIBLookupComboEditBox.GetRelationNameQualifier: string;
208     begin
209     if FRelationName <> '' then
210     Result := FRelationName + '.'
211     else
212     Result := ''
213     end;
214    
215     procedure TIBLookupComboEditBox.ActiveChanged(Sender: TObject);
216     begin
217     if not FInserting and not FUpdating then
218     Application.QueueAsyncCall(@DoActiveChanged,0);
219 tony 27 IBControlLinkChanged;
220 tony 21 end;
221    
222     procedure TIBLookupComboEditBox.DoActiveChanged(Data: PtrInt);
223     begin
224     if AppDestroying in Application.Flags then Exit;
225    
226     if (DataSource = nil) and assigned(ListSource) and assigned(ListSource.DataSet)
227     and ListSource.DataSet.Active then
228     begin
229     begin
230     if varIsNull(FLastKeyValue) and (ItemIndex = -1) then
231     KeyValue := ListSource.DataSet.FieldByName(KeyField).AsVariant
232     else
233     begin
234     KeyValue := FLastKeyValue;
235     UpdateData(self); {Force auto scroll}
236     if varIsNull(KeyValue) then {Value not present}
237     Text := ListSource.DataSet.FieldByName(ListField).AsString
238     end;
239     end;
240     end
241     else
242     if (DataSource <> nil) and assigned(DataSource.DataSet) and
243     (DataSource.DataSet.Active) and (DataField <> '') then
244     begin
245     ResetParser;
246     KeyValue := Field.AsVariant;
247     end
248     else
249     Text := '';
250     FOriginalTextValue := Text;
251     end;
252    
253     function TIBLookupComboEditBox.GetAutoCompleteText: TComboBoxAutoCompleteText;
254     begin
255     Result := inherited AutoCompleteText;
256     if AutoComplete then
257     Result := Result + [cbactEnabled]
258     end;
259    
260     procedure TIBLookupComboEditBox.ResetParser;
261 tony 27 var curKeyValue: variant;
262 tony 21 begin
263     if FFiltered then
264     begin
265     FFiltered := false;
266 tony 27 curKeyValue := KeyValue;
267     Text := ''; {Ensure full list}
268 tony 21 UpdateList;
269 tony 27 KeyValue := curKeyValue;
270 tony 21 UpdateData(self); {Force Scroll}
271     end;
272     end;
273    
274     procedure TIBLookupComboEditBox.RecordChanged(Sender: TObject; aField: TField);
275     begin
276     {Make sure that we are in sync with other data controls}
277     if DataSource = nil then
278     begin
279     KeyValue := ListSource.DataSet.FieldByName(KeyField).AsVariant;
280     if VarIsNull(KeyValue) then {Probable deletion}
281     begin
282     UpdateList;
283     KeyValue := ListSource.DataSet.FieldByName(KeyField).AsVariant;
284     end;
285     end;
286     end;
287    
288     procedure TIBLookupComboEditBox.SetAutoCompleteText(
289     AValue: TComboBoxAutoCompleteText);
290     begin
291     if AValue <> AutoCompleteText then
292     begin
293     FAutoComplete := cbactEnabled in AValue;
294     inherited AutoCompleteText := AValue - [cbactEnabled]
295     end;
296     end;
297    
298     procedure TIBLookupComboEditBox.SetListSource(AValue: TDataSource);
299     begin
300     if AValue <> inherited ListSource then
301     begin
302     FDataLink.DataSource := AValue;
303     inherited ListSource := AValue;
304 tony 27 IBControlLinkChanged;
305 tony 21 end;
306     end;
307    
308     procedure TIBLookupComboEditBox.UpdateList;
309     { Note: Algorithm taken from TCustomComboBox.KeyUp but modified to use the
310     ListSource DataSet as the source for the autocomplete text. It also runs
311     after a delay rather than immediately on keyup
312     }
313     var
314     iSelStart: Integer; // char position
315     sCompleteText, sPrefixText, sResultText: string;
316     curText: string;
317     begin
318     if assigned(ListSource) and assigned(ListSource.DataSet) and (ListSource.DataSet is TIBCustomDataSet)
319     and ListSource.DataSet.Active then
320     begin
321     FUpdating := true;
322     try
323     iSelStart := SelStart;//Capture original cursor position
324     if ((iSelStart < UTF8Length(Text)) and
325     (cbactEndOfLineComplete in AutoCompleteText)) then
326     Exit;
327     curText := Text;
328     sPrefixText := UTF8Copy(Text, 1, iSelStart);
329     ListSource.DataSet.Active := false;
330     ListSource.DataSet.Active := true;
331     Text := curText;
332     if not FExiting and Focused and (Text <> '')then
333     begin
334     if ListSource.DataSet.Active and (ListSource.DataSet.RecordCount > 0) then
335     begin
336     sCompleteText := ListSource.DataSet.FieldByName(ListField).AsString;
337     if (sCompleteText <> Text) then
338     begin
339     sResultText := sCompleteText;
340     if ((cbactEndOfLineComplete in AutoCompleteText) and
341     (cbactRetainPrefixCase in AutoCompleteText)) then
342     begin//Retain Prefix Character cases
343     UTF8Delete(sResultText, 1, iSelStart);
344     UTF8Insert(sPrefixText, sResultText, 1);
345     end;
346     Text := sResultText;
347     SelStart := iSelStart;
348     SelLength := UTF8Length(Text);
349     end;
350     end;
351     end;
352     finally
353     FUpdating := false
354     end;
355     end;
356     end;
357    
358     procedure TIBLookupComboEditBox.UpdateSQL(Sender: TObject;
359     Parser: TSelectSQLParser);
360     var FieldPosition: integer;
361     begin
362     if FFiltered then
363     begin
364     if cbactSearchCaseSensitive in AutoCompleteText then
365 tony 27 Parser.Add2WhereClause(GetRelationNameQualifier + '"' + ListField + '" Like ''' +
366     SQLSafe(Text) + '%''')
367 tony 21 else
368 tony 27 Parser.Add2WhereClause(GetRelationNameQualifier + 'Upper("' + ListField + '") Like Upper(''' +
369     SQLSafe(Text) + '%'')');
370 tony 21
371     end;
372     if cbactSearchAscending in AutoCompleteText then
373     begin
374     FieldPosition := Parser.GetFieldPosition(ListField);
375     if FieldPosition = 0 then Exit;
376    
377     Parser.OrderByClause := IntToStr(FieldPosition) + ' ascending';
378     end;
379     end;
380    
381     procedure TIBLookupComboEditBox.HandleEnter(Data: PtrInt);
382     begin
383 tony 27 SelectAll
384 tony 21 end;
385    
386     procedure TIBLookupComboEditBox.UpdateLinkData(Sender: TObject);
387     begin
388     if FInserting then
389     ListSource.DataSet.FieldByName(ListField).AsString := Text
390     end;
391    
392     procedure TIBLookupComboEditBox.CheckAndInsert;
393     var Accept: boolean;
394     NewKeyValue: variant;
395     begin
396     if AutoInsert and (Text <> '') and assigned(ListSource) and assigned(ListSource.DataSet)
397     and ListSource.DataSet.Active and (ListSource.DataSet.RecordCount = 0) then
398     try
399     {Is it OK to insert a new list member?}
400     Accept := true;
401     if assigned(FOnCanAutoInsert) then
402     OnCanAutoInsert(self,Text,Accept);
403     if not Accept then
404     begin
405     ResetParser;
406     Text := FOriginalTextValue;
407     SelectAll;
408     Exit;
409     end;
410    
411     FInserting := true;
412     try
413     {New Value}
414     FFiltered := false;
415     if assigned(FOnAutoInsert) then
416     begin
417     {In an OnAutoInsert handler, the client is expected to insert the new
418     row into the List DataSet and to set the KeyValue property to the
419     value of the primary key of the new row.}
420     OnAutoInsert(self,Text,NewKeyValue);
421     end
422     else
423     begin
424     ListSource.DataSet.Append;
425     {The new KeyValue should be determined by an external generator or
426     in the "OnInsert" handler. If it is the same as the ListField, then
427     it will be set from the UpdateLinkData method}
428     try
429     ListSource.DataSet.Post;
430     except
431     ListSource.DataSet.Cancel;
432     raise;
433     end;
434     NewKeyValue := ListSource.DataSet.FieldByName(KeyField).AsVariant;
435     end;
436 tony 23 Text := ''; {Ensure full list}
437 tony 21 UpdateList;
438     KeyValue := NewKeyValue;
439     UpdateData(nil); {Force sync with DataField}
440     finally
441     FInserting := false
442     end;
443     except
444     Text := FOriginalTextValue;
445     ResetParser;
446     raise;
447     end;
448     end;
449    
450     procedure TIBLookupComboEditBox.DoEnter;
451     begin
452     inherited DoEnter;
453     FOriginalTextValue:= Text;
454     ResetParser;
455     Application.QueueAsyncCall(@HandleEnter,0);
456     end;
457    
458     procedure TIBLookupComboEditBox.DoExit;
459     begin
460     FExiting := true;
461     try
462     CheckAndInsert;
463     ResetParser;
464     FTimer.Interval := 0;
465     finally
466     FExiting := false;
467     end;
468     inherited DoExit;
469     end;
470    
471     procedure TIBLookupComboEditBox.KeyUp(var Key: Word; Shift: TShiftState);
472     begin
473     inherited KeyUp(Key, Shift);
474     if Key = VK_RETURN then
475     EditingDone
476     else
477     if Key = VK_ESCAPE then
478     begin
479     SelStart := UTF8Length(Text); {Ensure end of line selection}
480     ResetParser;
481     Text := FOriginalTextValue;
482     SelectAll;
483     end
484     else
485     if (IsEditableTextKey(Key) or (Key = VK_BACK))
486     and AutoComplete and (Style <> csDropDownList) and
487     (not (cbactEndOfLineComplete in AutoCompleteText) or (SelStart = UTF8Length(Text))) then
488     FTimer.Interval := FKeyPressInterval
489     else
490 tony 29 FTimer.Interval := 0;
491 tony 21 end;
492    
493 tony 29 procedure TIBLookupComboEditBox.Loaded;
494     begin
495     inherited Loaded;
496     IBControlLinkChanged;
497     end;
498    
499 tony 27 procedure TIBLookupComboEditBox.Notification(AComponent: TComponent;
500     Operation: TOperation);
501     begin
502     inherited Notification(AComponent, Operation);
503     if (Operation = opRemove) and (AComponent = DataSource) then
504     ListSource := nil;
505     end;
506    
507 tony 21 procedure TIBLookupComboEditBox.SetItemIndex(const Val: integer);
508     begin
509     inherited SetItemIndex(Val);
510     FLastKeyValue := KeyValue;
511     end;
512    
513 tony 27 function TIBLookupComboEditBox.SQLSafe(aText: string): string;
514     var I: integer;
515     begin
516     Result := '';
517     for I := 1 to length(aText) do
518     if aText[I] = '''' then
519     Result := Result + ''''''
520     else
521     Result := Result + aText[I];
522     end;
523    
524 tony 21 procedure TIBLookupComboEditBox.UpdateShowing;
525     begin
526     inherited UpdateShowing;
527     if Showing then {Ensure up-to-date as we were ignoring any changes}
528     ActiveChanged(nil);
529     end;
530    
531     constructor TIBLookupComboEditBox.Create(TheComponent: TComponent);
532     begin
533     inherited Create(TheComponent);
534     FDataLink := TIBLookupComboDataLink.Create(self);
535 tony 27 FIBLookupControlLink := TIBLookupControlLink.Create(self);
536     FKeyPressInterval := 200;
537 tony 21 FAutoComplete := true;
538     FTimer := TTimer.Create(nil);
539     FTimer.Interval := 0;
540     FTimer.OnTimer := @HandleTimer;
541     FLastKeyValue := NULL;
542     end;
543    
544     destructor TIBLookupComboEditBox.Destroy;
545     begin
546     if assigned(FDataLink) then FDataLink.Free;
547 tony 27 if assigned(FIBLookupControlLink) then FIBLookupControlLink.Free;
548 tony 21 if assigned(FTimer) then FTimer.Free;
549     inherited Destroy;
550     end;
551    
552     procedure TIBLookupComboEditBox.EditingDone;
553     begin
554     CheckAndInsert;
555     inherited EditingDone;
556     end;
557    
558     end.