根据文档,我尝试将NSTextStorage子类化并在文本视图中使用它:
/*
NSTextStorage is a semi-abstract subclass of NSMutableAttributedString. It
implements change management (beginEditing/endEditing), verification of
attributes, delegate handling, and layout management notification. The one
aspect it does not implement is the actual attributed string storage --- this is
left up to the subclassers, which need to override the two
NSMutableAttributedString primitives:
- (void)replaceCharactersInRange:(NSRange)range withString:(NSString *)str;
- (void)setAttributes:(NSDictionary *)attrs range:(NSRange)range;
*/
所以我尝试使用delegate来处理具有相同功能的所有需要的事件:
@implementation MyTextStorage
- (id) init {
self = [super init];
if (self != nil) {
storage = [[NSMutableAttributedString alloc] init];
}
return self;
}
- (void) dealloc {
[storage release];
[super dealloc];
}
- (NSString *) string {
return [storage string];
}
- (void) replaceCharactersInRange:(NSRange)range withString:(NSString *)str {
[storage replaceCharactersInRange:range withString:str];
}
- (void)setAttributes:(NSDictionary *)attrs range:(NSRange)range {
[storage setAttributes:attrs range:range];
}
@end
无论我使用什么作为委托:NSTextStorage或NSMutableAttributedString,结果都是一样的:
提出了未被捕获的例外情况 * NSRunStorage,_ NSBlockNumberForIndex():索引(18446744073709551615)超出数组 边界(0) * 由于未捕获的异常“NSRangeException”而终止应用,原因如下: '*** NSRunStorage, _NSBlockNumberForIndex():索引(18446744073709551615)超出数组 bounds(0)'
堆栈追踪:
0 CoreFoundation 0x00007fff840cd7b4 __exceptionPreprocess + 180
1 libobjc.A.dylib 0x00007fff885390f3 objc_exception_throw + 45
2 CoreFoundation 0x00007fff840cd5d7 +[NSException raise:format:arguments:] + 103
3 CoreFoundation 0x00007fff840cd564 +[NSException raise:format:] + 148
4 AppKit 0x00007fff86cc6288 _NSBlockNumberForIndex + 86
5 AppKit 0x00007fff86cc71d5 -[NSLayoutManager textContainerForGlyphAtIndex:effectiveRange:] + 364
6 AppKit 0x00007fff86d1f121 -[NSTextView(NSSharing) didChangeText] + 340
7 AppKit 0x00007fff86d44b68 -[NSTextView insertText:replacementRange:] + 2763
8 CocoaCalculator 0x0000000100002312 -[CalcTextView insertText:] + 65
9 CocoaCalculator 0x00000001000027ac -[CalcTextContainer initWithFrame:] + 1176
10 AppKit 0x00007fff86c23d44 -[NSCustomView nibInstantiate] + 646
11 AppKit 0x00007fff86b7be17 -[NSIBObjectData instantiateObject:] + 259
12 AppKit 0x00007fff86b7b202 -[NSIBObjectData nibInstantiateWithOwner:topLevelObjects:] + 336
13 AppKit 0x00007fff86b7988d loadNib + 226
14 AppKit 0x00007fff86b78d9a +[NSBundle(NSNibLoading) _loadNibFile:nameTable:withZone:ownerBundle:]
当我尝试拨打
时终止开始[textView insertText:@"123"];
但是在标准的NSTextStorage版本中,一切正常。
我需要做些什么来扩展这个课程?
答案 0 :(得分:11)
除了需要实施的NSAttributedString原语方法之外,我相信您还需要分别在edited:range:changeInLength:
和replaceCharactersInRange:withString:
的覆盖范围内调用setAttributes:range:
。
类似的东西:
- (void) replaceCharactersInRange:(NSRange)range withString:(NSString *)str {
[storage replaceCharactersInRange:range withString:str];
[self edited:NSTextStorageEditedCharacters range:range changeInLength:[str length] - range.length];
}
- (void)setAttributes:(NSDictionary *)attrs range:(NSRange)range {
[storage setAttributes:attrs range:range];
[self edited:NSTextStorageEditedAttributes range:range changeInLength:0];
}
答案 1 :(得分:5)
NSTextStorage
文档在这方面有点模糊。您在问题中引用的注释,只需要覆盖2个NSMutableAttributedString
原语只意味着您不必覆盖其他NSMutableAttributedString
原语。
您仍然必须覆盖NSAttributedString
超类的基元。这意味着您需要实施-attributesAtIndex:effectiveRange:
,-length
和-string
。我注意到你确实包含了-string
的实现,所以剩下的两个应该这样做。
如果你添加:
- (NSUInteger)length
{
return [storage length];
}
- (NSDictionary *)attributesAtIndex:(NSUInteger)location effectiveRange:(NSRangePointer)range
{
return [storage attributesAtIndex:location effectiveRange:range];
}
...希望它能解决这个问题。