1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
/*
Grr RSS Reader
Copyright (C) 2006, 2007 Guenther Noack <guenther@unix-ag.uni-kl.de>
Copyright (C) 2009 GNUstep Application Team
Riccardo Mottola
This application is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
This application is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA.
*/
#import <Foundation/NSSet.h>
#import <Foundation/NSArray.h>
#import "DatabaseElement.h"
@protocol Category <DatabaseElement>
/**
* Returns the child elements in this category.
*/
-(NSArray*) elements;
/**
* Inserts the given element in this category.
* Returns YES if - and only if - the operation is a success.
* Otherwise, NO is returned. The operation will fail when the
* element is already contained in this category.
*
* The position argument is an integer between 0 and the number
* of already existing database elements. A position of 0 inserts
* the new element before the first and a position equaling the
* number of elements inserts the new element after the last element.
*/
-(BOOL) insertElement: (id<DatabaseElement>)element
atPosition: (int)index;
/**
* This convenience method inserts a database element in a category
* without caring about the position. See the documentation for
* -insertElement:atPosition: for details.
*/
-(BOOL) insertElement: (id<DatabaseElement>)element;
/**
* Removes the given database element from the category. On success,
* YES is returned. This will only work if the element is a direct
* child of the category.
*/
-(BOOL) removeElement: (id<DatabaseElement>)element;
/**
* Recursively removes the given database element from the category.
* On success, YES is returned. This also removes the element if it's
* contained in a subcategory.
*/
-(BOOL) recursivelyRemoveElement: (id<DatabaseElement>)element;
@end
@interface GrrCategory : NSObject <Category>
{
// the parent element of this component
id<Category> parent;
// the array which contains all subelements
NSMutableArray* elements;
// the category name
NSString* name;
}
/**
* Initialises a named category with an empty element list.
*/
-(id) initWithName: (NSString*) aName;
/**
* Designated initialiser.
*/
-(id) initWithName: (NSString*) aName
elements: (NSArray*) anElementsArray;
// see Component protocol
@end
|
