How To Write Lazarus Component/ko: what changed

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Title: How To Write Lazarus Component/ko

New		Line
1	+	컴포넌츠 빌드방법에 대한 기본 안내서이다. 윈도우7 라자루스 0.9.30버전에서 테스트 되었다.
2	+
3	+	## 단계 1: 패키지 생성
4	+
5	+	- On the Lazarus IDE menu, click Package \> New Package to run the Package Manager.
6	+
7	+	<figure>
8	+	<img src="package_menu.png" title="package_menu.png" />
9	+	<figcaption>package_menu.png</figcaption>
10	+	</figure>
11	+
12	+	- A Save dialog file will appear. Chose a folder and a filename and press save. If the IDE prompts for using lowercase filenames press 'yes'.
13	+
14	+	- Congratulations: You have just created your first package!
15	+
16	+	<figure>
17	+	<img src="How_to_write_lazarus_component_package_maker.png" title="Package Maker" />
18	+	<figcaption>Package Maker</figcaption>
19	+	</figure>
20	+
21	+	## 단계 2: 유닛 생성
22	+
23	+	You can create a new unit or use an existing file.
24	+
25	+	### 새로운 유닛 생성
26	+
27	+	- Use the Add button \> New component.
28	+
29	+	<figure>
30	+	<img src="package_new_component.png" title="package_new_component.png" />
31	+	<figcaption>package_new_component.png</figcaption>
32	+	</figure>
33	+
34	+	- Choose a component like TComboBox.
35	+	- Choose customcontrol1.pas as filename.
36	+	- Click OK.
37	+
38	+	``` pascal
39	+	unit CustomControl1;
40	+
41	+	{$mode objfpc}{$H+}
42	+
43	+	interface
44	+
45	+	uses
46	+	Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, StdCtrls;
47	+
48	+	type
49	+	TCustomControl1 = class(TComboBox)
50	+	private
51	+	{ Private declarations }
52	+	protected
53	+	{ Protected declarations }
54	+	public
55	+	{ Public declarations }
56	+	published
57	+	{ Published declarations }
58	+	end;
59	+
60	+	procedure Register;
61	+
62	+	implementation
63	+
64	+	procedure Register;
65	+	begin
66	+	RegisterComponents('Standard',[TCustomControl1]);
67	+	end;
68	+
69	+	end.
70	+	```
71	+
72	+	- Install the package by clicking the 'install' button at the top of the package editor.
73	+
74	+	<figure>
75	+	<img src="package_install.png" title="package_install.png" />
76	+	<figcaption>package_install.png</figcaption>
77	+	</figure>
78	+
79	+	- Then the IDE will ask you, if the IDE should be rebuilt. Say yes.
80	+
81	+	<figure>
82	+	<img src="package_rebuild.png" title="package_rebuild.png" />
83	+	<figcaption>package_rebuild.png</figcaption>
84	+	</figure>
85	+
86	+	- Restart Lazarus and see your new component in the component palette. Congratulations: You have just installed your first package with your first package component.
87	+
88	+	<figure>
89	+	<img src="package_installed.png" title="package_installed.png" />
90	+	<figcaption>package_installed.png</figcaption>
91	+	</figure>
92	+
93	+	> Note: If you do not see your new component in the component palette, it is most likely that you are not running the re-compiled version of Lazarus. You can set where Lazarus builds to in: Tools -\> Options -\> Files -\> Lazarus directory. Instead of calling lazarus directly, you also can use startlazarus, which starts the newly created lazarus, for example the lazarus executable in the ~/.lazarus directory, if you don't have write access to the directory lazarus was installed into.
94	+
95	+	### 기존 유닛 추가
96	+
97	+	If you already had a unit you can add it to the package:
98	+
99	+	<figure>
100	+	<img src="package_existing_unit.png" title="package_existing_unit.png" />
101	+	<figcaption>package_existing_unit.png</figcaption>
102	+	</figure>
103	+
104	+	- Click the Add button, go to the Add Files tab. At the Unit file name, browse to your existing file. Click the Add files to package. If the packet manager complains that the unit is not in the unitpath, click yes to add the directory to the unit path.
105	+	- Click the Add button again, go to the Add Files tab and browse to the .lrs file and click OK (See Step 3 about creating this icon file).
106	+	- Click the Add button again, go to the New Requirement tab, in the Package name select LCL and click OK.
107	+
108	+	End result should look like this:
109	+
110	+	![`Package Maker`](/wiki-images/d/d9/How_to_write_lazarus_component_package_maker_done.png)
111	+
112	+	- Click on under the Files tree in the Package Manager. In the File Properties, make sure Register unit is checked.
113	+	- Click the Options button. Select the IDE Integration tab. At the Package Type make sure Designtime and Runtime is selected.
114	+	- Click the Compile button to check to see if the files compile without errors.
115	+	- Click the Install button, Lazarus will rebuild and restart automatically.
116	+
117	+	The component is created and ready to be used:
118	+
119	+	![`Component Created`](/wiki-images/3/3c/How_to_write_lazarus_component_created.png)
120	+
121	+	## 단계 3: 패키지 아이콘 생성
122	+
123	+	아이콘은 PNG 파일로 24x24 사이즈입니다.
124	+
125	+	FPC is capable of using standard resource files `.rc` or compiled resources `.res` since fpc version 2.6
126	+
127	+	The `.lrs`
128	+
129	+	### 라자루스 이미지 에디터 사용
130	+
131	+	You can use [[Lazarus Image Editor]] to create the icons in .lrs format.
132	+
133	+	### lazres 사용
134	+
135	+	`lazres`는 라자루스툴 디렉토리에 있는 located를 사용합니다.
136	+
137	+	You may need to compile lazres at first use. Simply open the lazres.lpi in the IDE and at the menu click run \> build.
138	+
139	+	Create lrs file
140	+
141	+	lrs 파일 생성:
142	+
143	+	`~/lazarus/tools/lazres samplepackage.lrs TMyCom.png`
144	+
145	+	Where samplepackage is the name of your package and TMyCom is the name of your component.
146	+
147	+	You can add more than one image to the lrs file by appending the image filename at the end. Eg. ~/lazarus/tools/lazres samplepackage.lrs TMyCom.png TMyOtherCom.png ...
148	+
149	+	샘플
150	+
151	+	Following is a sample of the resulting samplepackage.lrs file.
152	+
153	+	LazarusResources.Add('TMyCom','PNG',[
154	+	#137'PNG'#13#10#26#10#0#0#0#13'IHDR'#0#0#0#24#0#0#0#24#8#2#0#0#0'o'#21#170#175
155	+	+#0#0#0#4'gAMA'#0#0#177#143#11#252'a'#5#0#0#0'\|IDAT8O'#237#212#209#10#192' '#8
156	+	+#5'P'#247#231#251's'#215#138#133#164#166'\'#220#195'`'#209'c'#157'L'#173#131
157	+	+#153#169'd4'#168'dP'#137'r_'#235'5'#136'@Zmk'#16'd9'#144#176#232#164'1'#247
158	+	+'I'#8#160'IL'#206'C'#179#144#12#199#140'.'#134#244#141'~'#168#247#209'S~;'#29
159	+	+'V+'#196#201'^'#10#15#150'?'#255#18#227#206'NZ>42'#181#159#226#144#15'@'#201
160	+	+#148#168'e'#224'7f<@4'#130'u_YD'#23#213#131#134'Q]'#158#188#135#0#0#0#0'IEND'
161	+	+#174'B`'#130
162	+	]);
163	+
164	+	Make sure to include your resource file in your new component source by adding the following at the bottom your component's unit and including "LResources" in the uses clause
165	+
166	+	``` pascal
167	+	initialization
168	+	{$I samplepackage.lrs}
169	+	```
170	+
171	+	## 리컴파일링 패키지
172	+
173	+	You need to rebuild the package everytime you make changes to the mycom.pas file. To rebuild the package, open the samplepackage.lpk file in the Package Manager and click the Install button.
174	+
175	+	## 패키지 제거
176	+
177	+	- To remove installed components, on the IDE menu, click Package \> Configure installed packages. The following image shows the Installed Packages tool.
178	+
179	+	![`Installed Components`](/wiki-images/0/0e/How_to_write_lazarus_component_installed_components.png)
180	+
181	+	- Select the package you want to uninstall and click Uninstall selection.
182	+
183	+	If something goes wrong with a package (e.g. package directory is deleted without first uninstalling it), Lazarus may not allow you to uninstall packages. To fix the problem, at the IDE menu click Tools \> Build Lazarus. Lazarus will rebuild all packages and restart. You should now be able to uninstall problematic packages.
184	+
185	+	## mycom.pas 개선
186	+
187	+	- The codes in mycom.pas above gives you the basics on what you need to create a component. The following is an enhanced version with some tips on how to write procedures and events for components.
188	+	- OnChange2 이벤트를 만드는 방법을 보여줍니다
189	+	- The OnSample shows how to create custom events
190	+	- MyText and MyText2 shows different ways to write properties.
191	+	- You can use TComboBox instead of TCustomComboBox as the base class, which publishes all properties as TComboBox.
192	+	- If TCustomComboBox is used as the base class, you'll notice a lot of properties and events will be missing at the Object Inspector in the IDE. To add those properties and events just copy and paste the properties as listed below // properties from TComboBox. These list of properties can be got from the TComboBox declaration in the StdCtrls unit. Omit any property which you want to handle yourself.
193	+
194	+	``` pascal
195	+	unit mycom;
196	+
197	+	{$mode objfpc}{$H+}
198	+
199	+	interface
200	+
201	+	uses
202	+	Classes, SysUtils, StdCtrls, Forms, Dialogs,
203	+	LCLType,LCLIntf,lresources,LCLProc;
204	+
205	+	type
206	+
207	+	TSampleEvent = procedure(MyText: String) of Object;
208	+
209	+	TMyCom = class (TCustomComboBox)
210	+	private
211	+	FMyText: String;
212	+	FOnChange2: TNotifyEvent;
213	+	FOnSample: TSampleEvent;
214	+	public
215	+	constructor Create(TheOwner: TComponent); override;
216	+	procedure CreateWnd; override;
217	+	procedure Change; override;
218	+	protected
219	+	function GetMyText2: String;
220	+	procedure SetMyText2(MyText: String);
221	+	published
222	+	property MyText: String read FMyText write FMyText;
223	+	property MyText2: String read GetMyText2 write SetMyText2;
224	+	property OnChange2: TNotifyEvent read FOnChange2 write FOnChange2;
225	+	property OnSample: TSampleEvent read FOnSample write FOnSample;
226	+
227	+	// properties from TComboBox
228	+	property Align;
229	+	property Anchors;
230	+	property ArrowKeysTraverseList;
231	+	property AutoComplete;
232	+	property AutoCompleteText;
233	+	property AutoDropDown;
234	+	property AutoSelect;
235	+	property AutoSize;
236	+	property BidiMode;
237	+	property BorderSpacing;
238	+	property CharCase;
239	+	property Color;
240	+	property Ctl3D;
241	+	property Constraints;
242	+	property DragCursor;
243	+	property DragMode;
244	+	property DropDownCount;
245	+	property Enabled;
246	+	property Font;
247	+	property ItemHeight;
248	+	property ItemIndex;
249	+	property Items;
250	+	property ItemWidth;
251	+	property MaxLength;
252	+	property OnChange;
253	+	property OnChangeBounds;
254	+	property OnClick;
255	+	property OnCloseUp;
256	+	property OnContextPopup;
257	+	property OnDblClick;
258	+	property OnDragDrop;
259	+	property OnDragOver;
260	+	property OnDrawItem;
261	+	property OnEndDrag;
262	+	property OnDropDown;
263	+	property OnEditingDone;
264	+	property OnEnter;
265	+	property OnExit;
266	+	property OnGetItems;
267	+	property OnKeyDown;
268	+	property OnKeyPress;
269	+	property OnKeyUp;
270	+	property OnMeasureItem;
271	+	property OnMouseDown;
272	+	property OnMouseMove;
273	+	property OnMouseUp;
274	+	property OnStartDrag;
275	+	property OnSelect;
276	+	property OnUTF8KeyPress;
277	+	property ParentBidiMode;
278	+	property ParentColor;
279	+	property ParentCtl3D;
280	+	property ParentFont;
281	+	property ParentShowHint;
282	+	property PopupMenu;
283	+	property ReadOnly;
284	+	property ShowHint;
285	+	property Sorted;
286	+	property Style;
287	+	property TabOrder;
288	+	property TabStop;
289	+	property Text;
290	+	property Visible;
291	+	end;
292	+
293	+	procedure Register;
294	+
295	+	implementation
296	+
297	+	procedure Register;
298	+	begin
299	+	RegisterComponents('Sample',[TMyCom]);
300	+	end;
301	+
302	+	constructor TMyCom.Create(TheOwner: TComponent);
303	+	begin
304	+	inherited Create(TheOwner);
305	+	Self.Style := csDropDownList;
306	+	end;
307	+
308	+	procedure TMyCom.CreateWnd;
309	+	begin
310	+	inherited CreateWnd;
311	+	Items.Assign(Screen.Fonts);
312	+	end;
313	+
314	+	procedure TMyCom.Change;
315	+	begin
316	+	inherited;
317	+	if Assigned(FOnChange2) then FOnChange2(Self);
318	+	if Assigned(FOnSample) then FOnSample(FMyText);
319	+	end;
320	+
321	+	function TMyCom.GetMyText2: String;
322	+	begin
323	+	Result:=FMyText;
324	+	end;
325	+
326	+	procedure TMyCom.SetMyText2(MyText: String);
327	+	begin
328	+	FMyText:=MyText;
329	+	end;
330	+
331	+	initialization
332	+	{$I samplepackage.lrs}
333	+
334	+	end.
335	+	```
336	+
337	+	## 내장 (시각)컨포넌트 사용
338	+
339	+	It's possible to use standard components embedded in your own components (look for example at TLabeledEdit or TButtonPanel). Let's say you want to create a custom panel with a TLabel on it. With the steps described above the base package and source files can be created. Now to add a TLabel to the component, do the following:
340	+
341	+	- Add a private attribute for the label component (FEmbeddedLabel: TLabel;).
342	+	- Add a published read-only property for the label component (property EmbeddedLabel: TLabel read FEmbeddedLabel;)
343	+	- Create the label in the component's (overridden) constructor (FEmbeddedLabel := TLabel.Create(self); )
344	+	- Set the parent of the component (FEmbeddedLabel.Parent := self;)
345	+	- If the component to be embedded is not a 'subcomponent' by default (like TBoundLabel, TPanelBitBtn etc.) then add the call to SetSubComponent. This is necessary for the IDE so it knows that it has to store the properties of the embedded component as well. TLabel is not a subcomponent by default so the call to the method must be added (FEmbeddedLabel.SetSubComponent(true);).
346	+
347	+	To sum it up you would get something like this (only the essential parts are shown):
348	+
349	+	``` pascal
350	+	TEnhancedPanel = class(TCustomControl)
351	+	private
352	+	{ The new attribute for the embedded label }
353	+	FEmbeddedLabel: TLabel;
354	+
355	+	public
356	+	{ The constructor must be overriden so the label can be created }
357	+	constructor Create(AOwner: TComponent); override;
358	+
359	+	published
360	+	{ Make the label visible in the IDE }
361	+	property EmbeddedLabel: TLabel read FEmbeddedLabel;
362	+	end;
363	+
364	+	implementation
365	+
366	+	constructor TEnhancedPanel.Create(AOwner: TComponent);
367	+	begin
368	+	inherited Create(AOwner);
369	+
370	+	// Set default width and height
371	+	with GetControlClassDefaultSize do
372	+	SetInitialBounds(0, 0, CX, CY);
373	+
374	+	// Add the embedded label
375	+	FEmbeddedLabel := TLabel.Create(Self); // Add the embedded label
376	+	FEmbeddedLabel.Parent := self; // Show the label in the panel
377	+	FEmbeddedLabel.SetSubComponent(true); // Tell the IDE to store the modified properties
378	+	FLabel.Name := 'EmbeddedLabel';
379	+	FLabel.Caption := 'Howdy World!';
380	+
381	+	// Make sure the embedded label can not be selected/deleted within the IDE
382	+	FLabel.ControlStyle := FLabel.ControlStyle - [csNoDesignSelectable];
383	+
384	+	// Set other properties if necessary
385	+	//...
386	+
387	+	end;
388	+	```
389	+
390	+	## Using custom paint procedure
391	+
392	+	You can always subclass a component inside your program. For example, this implements a custom Paint procedure to a TLabel:
393	+
394	+	``` pascal
395	+	type
396	+	TMyLabel = class(TLabel)
397	+	public
398	+	procedure Paint; override;
399	+	end;
400	+	{...}
401	+	implementation
402	+	{...}
403	+	procedure TMyLabel.Paint;
404	+	begin
405	+	// your code to implement Paint, for example
406	+	Canvas.TextOut(0,0,Caption);
407	+	end;
408	+	```
409	+
410	+	Now you can create a MyLabel inside your program, at run time, with that overridden Paint procedure instead of the standard one.
411	+
412	+	For most components, and for most methods, it would be recommendable to call inherited procedure iniside it:
413	+
414	+	``` pascal
415	+	procedure TMyLabel.Paint;
416	+	begin
417	+
418	+	inherited Paint; /////////////////////
419	+
420	+	// your code to implement Paint, for example
421	+	Canvas.TextOut(0,0,Caption);
422	+	end;
423	+	```
424	+
425	+	But inherited behavior is not desirable in this case, since the second writing action would overlap the first (inherited) one.
426	+
427	+	## IDE와 컴포넌트를 통합
428	+
429	+	### Property Editors
430	+
431	+	Property editors provide custom dialogs to edit properties in the object inspector. For most properties, like strings, string lists, images, enumerated types and others, there are already default property editors, but if a custom component has a special kind of property it may require a custom dialog to edit the property. Each property editor is a class, which should descend from TPropertyEditor or one of it's descendents and implement methods from this base class. They should be registered in the 'Register' procedure by using the function RegisterPropertyEditor from the unit PropEdits. It is a standard to name property editors with the property name followed by 'Property', for example TFieldProperty for the property editor of the TField property.
432	+
433	+	``` pascal
434	+	TPropertyEditor = class
435	+	public
436	+	function AllEqual: Boolean; Virtual;
437	+	function AutoFill: Boolean; Virtual;
438	+	procedure Edit; Virtual; // Activated by double-clicking the property value
439	+	procedure ShowValue; Virtual; // Activated by control-clicking the property value
440	+	function GetAttributes: TPropertyAttributes; Virtual;
441	+	function GetEditLimit: Integer; Virtual;
442	+	function GetName: ShortString; Virtual;
443	+	procedure GetProperties(Proc: TGetPropEditProc); Virtual;
444	+	function GetHint(HintType: TPropEditHint; x, y: integer): String; Virtual;
445	+	function GetDefaultValue: AnsiString; Virtual;
446	+	procedure GetValues(Proc: TGetStrProc); Virtual;
447	+	procedure SetValue(const NewValue: AnsiString); Virtual;
448	+	procedure UpdateSubProperties; Virtual;
449	+	function SubPropertiesNeedsUpdate: Boolean; Virtual;
450	+	function IsDefaultValue: Boolean; Virtual;
451	+	function IsNotDefaultValue: Boolean; Virtual;
452	+	// ... shortened
453	+	end;
454	+	```
455	+
456	+	A good example for a property editor is the TFont property editor.
457	+
458	+	One of the most common cases for property editors is properties which are classes, because classes have many fields and can have a variety of formats, it's not possible for Lazarus to have the object inspector edit field able to edit it, like is done for strings and numeric types. For classes a convention is to have the value field show permanently the name of the class in parentheses, for example „(TFont)“ and the „...“ button shows a dialog to edit this class. This behavior, except for the dialog, is implemented by a standard property editor for classes called TClassPropertyEditor, which can be inherited from when writing property editors for classes:
459	+
460	+	``` pascal
461	+	TClassPropertyEditor = class(TPropertyEditor)
462	+	public
463	+	constructor Create(Hook: TPropertyEditorHook; APropCount: Integer); Override;
464	+	function GetAttributes: TPropertyAttributes; Override;
465	+	procedure GetProperties(Proc: TGetPropEditProc); Override;
466	+	function GetValue: AnsiString; Override;
467	+	property SubPropsTypeFilter: TTypeKinds Read FSubPropsTypeFilter
468	+	Write SetSubPropsTypeFilter
469	+	Default tkAny;
470	+	end;
471	+	```
472	+
473	+	Going back to the TFont example, inheriting from TClassPropertyEditor already offers part of the desired behavior and then the TFontPropertyEditor class only needs to implement showing the dialog in the Edit method and set the attributes for the editor:
474	+
475	+	``` pascal
476	+	TFontPropertyEditor = class(TClassPropertyEditor)
477	+	public
478	+	procedure Edit; Override;
479	+	function GetAttributes: TPropertyAttributes; Override;
480	+	end;
481	+
482	+	procedure TFontPropertyEditor.Edit;
483	+	var
484	+	FontDialog: TFontDialog;
485	+	begin
486	+	FontDialog := TFontDialog.Create(NIL);
487	+	try
488	+	FontDialog.Font := TFont(GetObjectValue(TFont));
489	+	FontDialog.Options := FontDialog.Options + [fdShowHelp, fdForceFontExist];
490	+	if FontDialog.Execute then SetPtrValue(FontDialog.Font);
491	+	finally
492	+	FontDialog.Free;
493	+	end;
494	+	end;
495	+
496	+	function TFontPropertyEditor.GetAttributes: TPropertyAttributes;
497	+	begin
498	+	Result := [paMultiSelect, paSubProperties, paDialog, paReadOnly];
499	+	end;
500	+	```
501	+
502	+	### 컴포넌트 에디터
503	+
504	+	Component editors control the behavior of right-clicking and double clicking components in the form designer. Each component editor is a class, which should descend from TComponentEditor or one of it's descendents and implement methods from this base class. They should be registered in the 'Register' procedure by using the function RegisterComponentEditor from the unit ComponentEditors. It is a standard to name component editors with the component name followed by 'Editor', for example TStringGridComponentEditor for the property editor of the TStringGrid component. Although user component editors should be based in TComponentEditor, most of it's methods are actually from an ancestor, so it is necessary to also know TBaseComponentEditor:
505	+
506	+	``` pascal
507	+	TBaseComponentEditor = class
508	+	protected
509	+	public
510	+	constructor Create(AComponent: TComponent;
511	+	ADesigner: TComponentEditorDesigner); Virtual;
512	+	procedure Edit; Virtual; Abstract;
513	+	procedure ExecuteVerb(Index: Integer); Virtual; Abstract;
514	+	function GetVerb(Index: Integer): String; Virtual; Abstract;
515	+	function GetVerbCount: Integer; Virtual; Abstract;
516	+	procedure PrepareItem(Index: Integer; const AnItem: TMenuItem); Virtual; Abstract;
517	+	procedure Copy; Virtual; Abstract;
518	+	function IsInInlined: Boolean; Virtual; Abstract;
519	+	function GetComponent: TComponent; Virtual; Abstract;
520	+	function GetDesigner: TComponentEditorDesigner; Virtual; Abstract;
521	+	function GetHook(out Hook: TPropertyEditorHook): Boolean; Virtual; Abstract;
522	+	procedure Modified; Virtual; Abstract;
523	+	end;
524	+	```
525	+
526	+	The most important method of a component editor is Edit, which is called when the component is double clicked. When the context menu for the component is invoked the GetVerbCount and GetVerb methods are called to build the menu. If one of the verbs (which means menu items in this case) are selected, ExecuteVerb is called. There is a default component editor (TDefaultEditor) which implements Edit to search the properties of the component for the most appropriate one to be edited. It usually chooses an event, which is edited by adding it's skeleton code in the code editor and setting the cursor to be in place to add code for it.
527	+
528	+	Other important methods from TBasComponentEditor are: ExecuteVerb(Index), which executes one of the extra menu items placed on the right-click popup menu; GetVerb – To return the name of each extra popup menu item. Note that t is the responsibility of the component editor to place special menu item caption characters like & to create a keyboard accelerator and “-” to create a separator; GetVerbCount – Returns the amount of items to be added to the popup menu. The index for the routines GetVerb and ExecuteVerb is zero based, going from 0 to GetVerbCount – 1; PrepareItem – Called for each verb after the menu item was created. Allows the menu item to be customized such as by adding subitems, adding a checkbox or even hiding it by setting Visible to false; Copy - Called when the component is being copied to the clipboard. The component data for use by Lazarus will always be added and cannot be modified. This method is instead for adding a different kind of clipboard information to paste the component in other applications, but which won't affect the Lazarus paste.
529	+
530	+	A simple and interesting example is the TCheckListBox component editor which creates a dialog to edit. More convenient then implementing all methods from TBaseComponentEditor is inheriting from TComponentEditor, and this is what TCheckListBoxEditor does. This base class adds empty implementations for most methods and some default ones for others. For Edit it calls ExecuteVerb(0), so if the first item will be identical to the double-click action, which is a convention for editor, there is no need to implement Edit. This basic action for the double-click and first menu item is often a dialog, and for TCheckListBox this is also done:
531	+
532	+	``` pascal
533	+	TCheckListBoxComponentEditor = class(TComponentEditor)
534	+	protected
535	+	procedure DoShowEditor;
536	+	public
537	+	procedure ExecuteVerb(Index: Integer); override;
538	+	function GetVerb(Index: Integer): String; override;
539	+	function GetVerbCount: Integer; override;
540	+	end;
541	+
542	+	procedure TCheckGroupComponentEditor.DoShowEditor;
543	+	var
544	+	Dlg: TCheckGroupEditorDlg;
545	+	begin
546	+	Dlg := TCheckGroupEditorDlg.Create(NIL);
547	+	try
548	+	// .. shortened
549	+	Dlg.ShowModal;
550	+	// .. shortened
551	+	finally
552	+	Dlg.Free;
553	+	end;
554	+	end;
555	+
556	+	procedure TCheckGroupComponentEditor.ExecuteVerb(Index: Integer);
557	+	begin
558	+	case Index of
559	+	0: DoShowEditor;
560	+	end;
561	+	end;
562	+
563	+	function TCheckGroupComponentEditor.GetVerb(Index: Integer): String;
564	+	begin
565	+	Result := 'CheckBox Editor...';
566	+	end;
567	+
568	+	function TCheckGroupComponentEditor.GetVerbCount: Integer;
569	+	begin
570	+	Result := 1;
571	+	end;
572	+	```
573	+
574	+	## 같이 보기
575	+
576	+	- [[Extending the IDE]]
577	+	- [[Lazarus Packages]] - A guide for creating a package under Lazarus
578	+	- [[Components and Code examples]]
579	+	- [[Lazarus Components]]
580	+	- [[IDE Window: Add to Package]]
581	+
582	+	You can post questions regarding this page [here](http://forum.lazarus.freepascal.org/index.php/topic,5789.0.html)
583	+
584	+	---
585	+	From the Free Pascal wiki, page "How To Write Lazarus Component/ko", as it stood on 2020-02-17 after a change by Trev, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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