Menu
▾
▴
[Instantobjects-cvscommit] SF.net SVN: instantobjects: [754] trunk/Help
|
From: <sr...@us...> - 2007-01-20 07:37:45
|
Revision: 754
http://svn.sourceforge.net/instantobjects/revision/?rev=754&view=rev
Author: srmitch
Date: 2007-01-19 23:37:39 -0800 (Fri, 19 Jan 2007)
Log Message:
-----------
- Updated Help file topics 'Associating Objects' and 'InstantObject.AddRef'.
Modified Paths:
--------------
trunk/Help/IOHelp.chm
trunk/Help/IOHelp.cnt
trunk/Help/IOHelp.hlp
trunk/Help/IOHelp.hpj
trunk/Help/IOHelp.hsc
trunk/Help/IOHelp.rtf
Modified: trunk/Help/IOHelp.chm
===================================================================
(Binary files differ)
Modified: trunk/Help/IOHelp.cnt
===================================================================
--- trunk/Help/IOHelp.cnt 2007-01-17 07:59:37 UTC (rev 753)
+++ trunk/Help/IOHelp.cnt 2007-01-20 07:37:39 UTC (rev 754)
@@ -1,4 +1,4 @@
-;This help file was created with HelpScribble 7.6.1
+;This help file was created with HelpScribble 7.7.0
;Licensed to: Steven Mitchell
:BASE IOHelp.hlp
Modified: trunk/Help/IOHelp.hlp
===================================================================
(Binary files differ)
Modified: trunk/Help/IOHelp.hpj
===================================================================
--- trunk/Help/IOHelp.hpj 2007-01-17 07:59:37 UTC (rev 753)
+++ trunk/Help/IOHelp.hpj 2007-01-20 07:37:39 UTC (rev 754)
@@ -1,20 +1,20 @@
; InstantObjects Help
;
-; This help file was created with HelpScribble 7.6.1
+; This help file was created with HelpScribble 7.7.0
; Licensed to: Steven Mitchell
-; HelpScribble is copyright (c) 1996-2005 Jan Goyvaerts
+; HelpScribble is copyright (c) 1996-2007 Jan Goyvaerts
; Visit http://www.helpscribble.com/ for more information
[OPTIONS]
REPORT=YES
-BMROOT=D:\L\INSTAN~1\Help\,D:\L\INSTAN~1\Help
+BMROOT=D:\L\IN121C~1\Help,D:\L\IN121C~1\Help
COMPRESS=True
LCID=0x0409
CNT=IOHelp.cnt
-ROOT=D:\L\INSTAN~1\Help
+ROOT=D:\L\IN121C~1\Help
TITLE=InstantObjects Help
[CONFIG]
@@ -26,7 +26,7 @@
nav="InstantObjects Guide",(200,410,220,503),0,(255,255,255),(255,255,255),0
[FILES]
-D:\L\INSTAN~1\Help\IOHelp.rtf
+D:\L\IN121C~1\Help\IOHelp.rtf
[MAP]
Scribble10 10
Modified: trunk/Help/IOHelp.hsc
===================================================================
--- trunk/Help/IOHelp.hsc 2007-01-17 07:59:37 UTC (rev 753)
+++ trunk/Help/IOHelp.hsc 2007-01-20 07:37:39 UTC (rev 754)
@@ -1273,15 +1273,19 @@
FALSE
-9
-{\rtf1\ansi\ansicpg1252\deff0{\fonttbl{\f0\fswiss Arial;}}
+13
+{\rtf1\ansi\ansicpg1252\deff0{\fonttbl{\f0\fswiss Arial;}{\f1\fswiss\fcharset0 Arial;}{\f2\fnil\fcharset2 Symbol;}}
{\colortbl ;\red0\green0\blue0;\red0\green128\blue0;\red128\green0\blue0;}
\viewkind4\uc1\pard\lang1040\b\f0\fs24 Associating Objects\cf1\b0\fs16
\par \pard\sb25\tx1435\cf2\strike Example 1\cf3\strike0\{linkID=430>example\}\cf1\tab\cf2\strike Programming with Persistent Objects\cf3\strike0\{linkID=340>main\}\{keepn\}\cf1
-\par \pard\sb25\sa25\tx1435\fs18 Persistent object relations defined by relational attributes in the business model can be accessed just as easy as any other attribute.
+\par \pard\sb25\sa25\tx1435\fs18 Persistent object relations \lang1033\f1 are \lang1040\f0 defined by relational attributes in the business model \lang1033\f1 and \lang1040\f0 can be accessed just as easy as any other attribute.
\par Single object relations defined by Part and Reference attributes are accessed through the corresponding object property of the class.
\par Multiple object references defined by Parts and References attributes are accessed through the corresponding array property and the container methods defined for the attribute.
\par
+\par \lang1033\b\f1 Assignment to \lang1040\f0 relational attributes
+\par \lang1033\b0\f1 (A close study of the code in \cf2\strike Example 1\cf3\strike0\{linkID=430>example\}\cf1 will help to clarify the points below.)\lang1040\f0
+\par \pard{\pntext\f2\'B7\tab}{\*\pn\pnlvlblt\pnf2\pnindent0{\pntxtb\'B7}}\fi-200\li200\sb25\sa25\tx200\lang1033\f1 O\lang1040\f0 bjects created \lang1033\f1 and\lang1040\f0 then assigned to \i part/parts attributes\i0 \lang1033\f1 SHOULD \lang1040\f0 NOT be freed after assignment. These attributes expect \lang1033\f1 the \lang1040\f0 transfer to them \lang1033\f1 of\lang1040\f0 ownership of the objects that they are assigned.\lang1033\f1 \lang1040\f0 The reference count\lang1033\f1 s\lang1040\f0 of these objects do not change during assignment.\lang1033\f1 \lang1040\f0 This means that\lang1033\f1 ,\lang1040\f0 when an object\lang1033\f1 is\lang1040\f0 create\lang1033\f1 d\lang1040\f0 and assign\lang1033\f1 ed\lang1040\f0 to a part/parts\lang1033\f1 \lang1040\f0 attribute\lang1033\f1 ,\lang1040\f0 the object that \lang1033\f1 was\lang1040\f0 created must \lang1033\f1 NOT be\lang1040\f0 free\lang1033\f1 d\lang1040\f0 unless an exception is raised during the\lang1033\f1 a\lang1040\f0 ssignment.\lang1033\f1 \lang1040\f0
+\par \lang1033\f1{\pntext\f2\'B7\tab}O\lang1040\f0 bjects created \lang1033\f1 and\lang1040\f0 then assigned to \i reference/references\lang1033\f1 \lang1040\f0 attributes\i0 DO need to be freed after assignment. These\lang1033\f1 \lang1040\f0 attributes DO NOT expect \lang1033\f1 the\lang1040\f0 transfer \lang1033\f1 of\lang1040\f0 ownership to them of the\lang1033\f1 \lang1040\f0 objects that they are assigned. The reference count of each of these\lang1033\f1 \lang1040\f0 objects is incremented during assignment. This means that\lang1033\f1 ,\lang1040\f0 when an object \lang1033\f1 is \lang1040\f0 create\lang1033\f1 d\lang1040\f0 and assign\lang1033\f1 ed\lang1040\f0 to a reference/references attribute\lang1033\f1 ,\lang1040\f0 the object that \lang1033\f1 was\lang1040\f0 created must \lang1033\f1 be \lang1040\f0 free\lang1033\f1 d\lang1040\f0 at some point after the\lang1033\f1 \lang1040\f0 assignment\lang1033\f1 to avoid a possible memory leak\lang1040\f0 .
\par }
430
Scribble430
@@ -1295,7 +1299,7 @@
FALSE
-123
+142
{\rtf1\ansi\ansicpg1252\deff0{\fonttbl{\f0\fswiss Arial;}{\f1\fmodern Courier New;}{\f2\fswiss\fcharset0 Arial;}{\f3\fnil Arial;}{\f4\fmodern\fcharset0 Courier New;}}
{\colortbl ;\red0\green0\blue0;\red0\green128\blue0;\red128\green0\blue0;}
\viewkind4\uc1\pard\lang1040\b\f0\fs24 Example 1 \cf1\b0\fs16
@@ -1355,16 +1359,35 @@
\par Result.Address.Street := 'Summer Street 1';
\par Result.Company := Company;
\par
-\par \{\- Add phones \}
+\par \{\f4\- Add phones \}
\par Phone := TPhone.Create;
-\par Phone.Name := 'Home';
-\par Phone.Number := '12345678';
-\par Result.AddPhone(Phone);
+\par try
+\par Phone.Name := 'Home';
+\par Phone.Number := '12345678';
+\par Result.AddPhone(Phone);
+\par except
+\par Phone.Free;
+\par raise;
+\par end;
\par Phone := TPhone.Create;
-\par Phone.Name := 'Office';
-\par Phone.Number := '32187654';
-\par Result.AddPhone(Phone);
-\par
+\par try
+\par Phone.Name := 'Office';
+\par Phone.Number := '32187654';
+\par Result.AddPhone(Phone);
+\par except
+\par Phone.Free;
+\par raise;
+\par end;
+\par \f1
+\par \f4 \f1\{\- Add \lang1033\f4 new Person as a Friend\lang1040\f1 \}\f4
+\par Person := TPerson.Create;
+\par try
+\par Person.Name := 'Fred Bloggs';
+\par Result.\f1 AddFriend\f4 (Person);
+\par finally
+\par Person.Free;
+\par end;
+\par \f1
\par \{\- Add colleagues\lang1033\f4 as Friends\lang1040\f1 \}
\par \b with \b0 TInstantSelector.Create(nil) \b do\b0
\par \b try\b0
@@ -1425,7 +1448,7 @@
Using an InstantQuery;InstantQuery,Using;
-
+programming:000050
Done
@@ -18223,17 +18246,20 @@
main
AddRef;AddRef_Method;TInstantObject_AddRef
-FALSE
-10
-{\rtf1\ansi\deff0{\fonttbl{\f0\fswiss Arial;}{\f1\fmodern Courier New;}}
+TRUE
+13
+{\rtf1\ansi\ansicpg1252\deff0{\fonttbl{\f0\fswiss Arial;}{\f1\fmodern Courier New;}{\f2\fswiss\fcharset0 Arial;}}
{\colortbl ;\red0\green0\blue0;}
\viewkind4\uc1\pard\lang1040\b\f0\fs24 TInstantObject.AddRef \cf1\b0\fs16
\par \pard\sb25\tx1435\strike TInstantObject\strike0\{linkID=7390>main\}\tab\ul See Also\ulnone\{linkID=7910\}\{keepn\}
\par \pard\sb25\sa85\tx1435\fs18 Increments the reference count for the number of references dependent on the instance.
\par \pard\sb25\sa25\tx1435\b\f1 function\b0 AddRef: Integer;
\par \pard\sb55\sa25\tx1435\b\f0 Description
-\par \pard\sb25\sa25\tx1435\b0 AddRef increments the reference count for the instance and returns the resulting value of the reference count. Although it should not normally be necessary to call AddRef directly, it can be called to safeguard an object before calling a method that could result in a premature destruction of the object, and after the method returns, call the \strike Release\strike0\{linkID=8920>main\} method to decrement the count.
-\par
+\par \pard\sb25\sa25\tx1435\b0 AddRef increments the reference count for the instance and returns the resulting value of the reference count.
+\par \fs10
+\par \fs18 Although it should not normally be necessary to call AddRef directly, it can be called\lang1033\f2 \lang1040\f0 to ensure the lifetime of an\lang1033\f2 \lang1040\f0 object\lang1033\f2 \lang1040\f0 before calling a method that could result in \lang1033\f2 the\lang1040\f0 premature destruction of the object, and after the method returns, call the \lang1033\f2 Free \lang1040\f0 method to decrement the \lang1033\f2 object's reference \lang1040\f0 count.\lang1033\f2 Note: It is generally not advisable to use the Release method in application development as this might result in memory leaks.\lang1040\f0
+\par \fs10
+\par \lang1033\f2\fs18 For practical examples of when to use the AddRef method study the PrimerCross demo application. One example is the TMainForm.CreateRandomContacts method in Main.pas. In that method a local Companies list is created. When an instance of TCompany is created its AddRef is called and it is added to the Companies list. However during the processing, instances of TCompany can be deleted from the list. As the list is a TObjectList, free will be called on its contained objects when items in the list are deleted or the list is destroyed. Calling AddRef when adding objects to the list ensures that the objects exist until they are deleted from the list or the list is destroyed thereby avoiding the possibility of an AV occurring.\lang1040\f0
\par }
7910
Scribble7910
@@ -20431,7 +20457,7 @@
main
Release;Release_Method;TInstantObject_Release
-FALSE
+TRUE
10
{\rtf1\ansi\deff0{\fonttbl{\f0\fswiss Arial;}{\f1\fmodern Courier New;}}
{\colortbl ;\red0\green0\blue0;}
Modified: trunk/Help/IOHelp.rtf
===================================================================
--- trunk/Help/IOHelp.rtf 2007-01-17 07:59:37 UTC (rev 753)
+++ trunk/Help/IOHelp.rtf 2007-01-20 07:37:39 UTC (rev 754)
@@ -970,10 +970,14 @@
}
\viewkind4\uc1\pard\keepn\lang1040\b\f0\fs24 Associating Objects\cf1\b0\fs16
\par \pard\keepn\sb25\tx1435\cf2\strike Example 1\cf3\strike0{\v Scribble430>example}\cf1\tab\cf2\strike Programming with Persistent Objects\cf3\strike0{\v Scribble340>main}\cf1
-\par \pard\sb25\sa25\tx1435\fs18 Persistent object relations defined by relational attributes in the business model can be accessed just as easy as any other attribute.
+\par \pard\sb25\sa25\tx1435\fs18 Persistent object relations \lang1033\f1 are \lang1040\f0 defined by relational attributes in the business model \lang1033\f1 and \lang1040\f0 can be accessed just as easy as any other attribute.
\par Single object relations defined by Part and Reference attributes are accessed through the corresponding object property of the class.
\par Multiple object references defined by Parts and References attributes are accessed through the corresponding array property and the container methods defined for the attribute.
\par
+\par \lang1033\b\f1 Assignment to \lang1040\f0 relational attributes
+\par \lang1033\b0\f1 (A close study of the code in \cf2\strike Example 1\cf3\strike0{\v Scribble430>example}\cf1 will help to clarify the points below.)\lang1040\f0
+\par \pard{\pntext\f6\'B7\tab}{\*\pn\pnlvlblt\pnf6\pnindent0{\pntxtb\'B7}}\fi-200\li200\sb25\sa25\tx200\lang1033\f1 O\lang1040\f0 bjects created \lang1033\f1 and\lang1040\f0 then assigned to \i part/parts attributes\i0 \lang1033\f1 SHOULD \lang1040\f0 NOT be freed after assignment. These attributes expect \lang1033\f1 the \lang1040\f0 transfer to them \lang1033\f1 of\lang1040\f0 ownership of the objects that they are assigned.\lang1033\f1 \lang1040\f0 The reference count\lang1033\f1 s\lang1040\f0 of these objects do not change during assignment.\lang1033\f1 \lang1040\f0 This means that\lang1033\f1 ,\lang1040\f0 when an object\lang1033\f1 is\lang1040\f0 create\lang1033\f1 d\lang1040\f0 and assign\lang1033\f1 ed\lang1040\f0 to a part/parts\lang1033\f1 \lang1040\f0 attribute\lang1033\f1 ,\lang1040\f0 the object that \lang1033\f1 was\lang1040\f0 created must \lang1033\f1 NOT be\lang1040\f0 free\lang1033\f1 d\lang1040\f0 unless an exception is raised during the\lang1033\f1 a\lang1040\f0 ssignment.\lang1033\f1 \lang1040\f0
+\par \lang1033\f1{\pntext\f6\'B7\tab}O\lang1040\f0 bjects created \lang1033\f1 and\lang1040\f0 then assigned to \i reference/references\lang1033\f1 \lang1040\f0 attributes\i0 DO need to be freed after assignment. These\lang1033\f1 \lang1040\f0 attributes DO NOT expect \lang1033\f1 the\lang1040\f0 transfer \lang1033\f1 of\lang1040\f0 ownership to them of the\lang1033\f1 \lang1040\f0 objects that they are assigned. The reference count of each of these\lang1033\f1 \lang1040\f0 objects is incremented during assignment. This means that\lang1033\f1 ,\lang1040\f0 when an object \lang1033\f1 is \lang1040\f0 create\lang1033\f1 d\lang1040\f0 and assign\lang1033\f1 ed\lang1040\f0 to a reference/references attribute\lang1033\f1 ,\lang1040\f0 the object that \lang1033\f1 was\lang1040\f0 created must \lang1033\f1 be \lang1040\f0 free\lang1033\f1 d\lang1040\f0 at some point after the\lang1033\f1 \lang1040\f0 assignment\lang1033\f1 to avoid a possible memory leak\lang1040\f0 .
\par \pard\plain\f0
{\page}
@@ -1040,16 +1044,35 @@
\par Result.Address.Street := 'Summer Street 1';
\par Result.Company := Company;
\par
-\par \{\- Add phones \}
+\par \{\f8\- Add phones \}
\par Phone := TPhone.Create;
-\par Phone.Name := 'Home';
-\par Phone.Number := '12345678';
-\par Result.AddPhone(Phone);
+\par try
+\par Phone.Name := 'Home';
+\par Phone.Number := '12345678';
+\par Result.AddPhone(Phone);
+\par except
+\par Phone.Free;
+\par raise;
+\par end;
\par Phone := TPhone.Create;
-\par Phone.Name := 'Office';
-\par Phone.Number := '32187654';
-\par Result.AddPhone(Phone);
-\par
+\par try
+\par Phone.Name := 'Office';
+\par Phone.Number := '32187654';
+\par Result.AddPhone(Phone);
+\par except
+\par Phone.Free;
+\par raise;
+\par end;
+\par \f7
+\par \f8 \f7\{\- Add \lang1033\f8 new Person as a Friend\lang1040\f7 \}\f8
+\par Person := TPerson.Create;
+\par try
+\par Person.Name := 'Fred Bloggs';
+\par Result.\f7 AddFriend\f8 (Person);
+\par finally
+\par Person.Free;
+\par end;
+\par \f7
\par \{\- Add colleagues\lang1033\f8 as Friends\lang1040\f7 \}
\par \b with \b0 TInstantSelector.Create(nil) \b do\b0
\par \b try\b0
@@ -1110,6 +1133,7 @@
{\pard\plain\f0\fs20
{\up #}{\footnote {\up #} Scribble440}
{\up $}{\footnote {\up $} Using an InstantQuery}
+{\up +}{\footnote {\up +} programming:000050}
{\up K}{\footnote {\up K} Using an InstantQuery;InstantQuery,Using;}
}
\viewkind4\uc1\pard\keepn\cf1\b\f0\fs24 Using an InstantQuery\b0\fs16
@@ -12729,8 +12753,11 @@
\par \pard\sb25\sa85\tx1435\fs18 Increments the reference count for the number of references dependent on the instance.
\par \pard\sb25\sa25\tx1435\b\f7 function\b0 AddRef: Integer;
\par \pard\sb55\sa25\tx1435\b\f0 Description
-\par \pard\sb25\sa25\tx1435\b0 AddRef increments the reference count for the instance and returns the resulting value of the reference count. Although it should not normally be necessary to call AddRef directly, it can be called to safeguard an object before calling a method that could result in a premature destruction of the object, and after the method returns, call the \strike Release\strike0{\v Scribble8920>main} method to decrement the count.
-\par
+\par \pard\sb25\sa25\tx1435\b0 AddRef increments the reference count for the instance and returns the resulting value of the reference count.
+\par \fs10
+\par \fs18 Although it should not normally be necessary to call AddRef directly, it can be called\lang1033\f1 \lang1040\f0 to ensure the lifetime of an\lang1033\f1 \lang1040\f0 object\lang1033\f1 \lang1040\f0 before calling a method that could result in \lang1033\f1 the\lang1040\f0 premature destruction of the object, and after the method returns, call the \lang1033\f1 Free \lang1040\f0 method to decrement the \lang1033\f1 object's reference \lang1040\f0 count.\lang1033\f1 Note: It is generally not advisable to use the Release method in application development as this might result in memory leaks.\lang1040\f0
+\par \fs10
+\par \lang1033\f1\fs18 For practical examples of when to use the AddRef method study the PrimerCross demo application. One example is the TMainForm.CreateRandomContacts method in Main.pas. In that method a local Companies list is created. When an instance of TCompany is created its AddRef is called and it is added to the Companies list. However during the processing, instances of TCompany can be deleted from the list. As the list is a TObjectList, free will be called on its contained objects when items in the list are deleted or the list is destroyed. Calling AddRef when adding objects to the list ensures that the objects exist until they are deleted from the list or the list is destroyed thereby avoiding the possibility of an AV occurring.\lang1040\f0
\par \pard\plain\f0
{\page}
|
