NSTextStorage-如何在文本中查找返回字符（换行）

Question

In an NSTextStorage I insert time strings at the current pointer location like this :

            NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString: @"00:00:00"];
            [attrString autorelease];
            int pos = [self selectedRange].location;
            [[self textStorage] insertAttributedString: attrString atIndex:pos];

So far so good, it works perfect. But now I want to position the pointer at the beginning of the next line. Obviously this is right after the next return char.

Now how to find the next return char in textStorage and position the pointer there ? I have not found any hint in the web for this task. Please help ...

Answer 1

You won't find a method to set the cursor (more precise: selection with zero length) in NSTextStorage 's API, because it is a storage, having no selection. The selection is a property of the text view. This is the result of MVC. Simply do a check: You can have many text views displaying the same text. Obviously each one needs its own selection.

What you have to do is to get the position of the next paragraph (this is better than searching for \\n ) and set this as a selection for the text view.

NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString: @"00:00:00"];
[attrString autorelease]; // You should *really* use ARC
int pos = [self selectedRange].location;
[[self textStorage] insertAttributedString: attrString atIndex:pos];

// Get the next paragraph
NSString *text = self.textStorage.string;
NSRange restOfStringRange = NSMakeRange( pos, [text length]-pos );
NSUInteger nextParagraphIndex;

// You have to look to the start of the next paragraph
[text getParagraphStart:&nextParagraphIndex end:NULL contentsEnd:NULL forRange:restOfStringRange];

NSTextView *view = self.textView; // Or where ever you get it from
view.selectedRange = NSMakeRange(nextParagraphIndex, 0);

Typed in Safari, not tested, just to show the basic approach.