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Some expository code from Notekata as a UITextInputTokenizer example
//Copyright (c) 2010, Allen Ding
//All rights reserved.
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions are met:
//
//1. Redistributions of source code must retain the above copyright notice, this
//list of conditions and the following disclaimer.
//
//2. Redistributions in binary form must reproduce the above copyright notice,
//this list of conditions and the following disclaimer in the documentation
//and/or other materials provided with the distribution.
//
//3. Neither the name of Allen Ding nor the names of any contributors may be
//used to endorse or promote products derived from this software without specific
//prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
//ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
//WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
//DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
//FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
//DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
//CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
//OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
//OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#import "KobaUI.h"
@class NKTTextView;
// NKTTextViewTokenizer is the tokenizer used by NKTTextView's implementation of the UITextInput
// protocol.
@interface NKTTextViewTokenizer : UITextInputStringTokenizer
{
@private
NKTTextView *textView_;
}
#pragma mark Initializing
- (id)initWithTextView:(NKTTextView *)textView;
@end
//Copyright (c) 2010, Allen Ding
//All rights reserved.
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions are met:
//
//1. Redistributions of source code must retain the above copyright notice, this
//list of conditions and the following disclaimer.
//
//2. Redistributions in binary form must reproduce the above copyright notice,
//this list of conditions and the following disclaimer in the documentation
//and/or other materials provided with the distribution.
//
//3. Neither the name of Allen Ding nor the names of any contributors may be
//used to endorse or promote products derived from this software without specific
//prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
//ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
//WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
//DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
//FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
//DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
//CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
//OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
//OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#define KBC_LOGGING_DISABLE_DEBUG_OUTPUT 1
#import "NKTTextViewTokenizer.h"
#import "KobaText.h"
#import "NKTTextPosition.h"
#import "NKTTextRange.h"
#import "NKTTextView.h"
// Either I am out of my mind or as of SDK 3.2, the recommended UITextInputStringTokenizer base
// implementation for the UITextInputTokenizer protocol is hopelessly broken (or has some weird
// semantics at the very least).
//
// As far as I can understand, theoretically NKTTextViewTokenizer only needs to handle the
// cases with line text granularity. Unfortunately, the behavior is absolutely bonkers if that
// is all we handle.
//
// Instead, as it stands, NKTTextViewTokenizer is almost a complete standalone implementation of
// the UITextInputTokenizer protocol, except in cases where the behavior provided by
// UITextInputStringTokenizer actually works as expected.
//
// Note that this implementation only supports left-to-right text.
//
// Overview:
// - Forward and backward refer to movement directions. NOT front/back of a text unit (e.g word)
// - A text unit has two boundaries - front and back
//
// Example:
// - Consider the phrase 'foobar mules x' and word granularity context
//
// - The word 'foobar' has two boundaries: 'f' and one-past 'r'
//
// - 'f' is a word boundary in the backward direction
// - one-past 'r' is word boundary in the forward direction
// - 'f' is only part of the word in the forward direction
// - one-past 'r' is only a part of the text unit in the backward direction
//
// +-------------+--------------+--------------+--------------+--------------+
// | | isPo:atB:fwd | isPo:atB:bwd | isPo:wTU:fwd | isPo:wTU:bwd |
// +-------------+--------------+--------------+--------------+--------------+
// | 'f' | | x | x | |
// | 'oobar' | | | x | x |
// | one-past'r' | x | | | x |
// +-------------+--------------+--------------+--------------+--------------+
//
// - one-past 'r' is the next word boundary in the forward direction from 'foobar'
// - 'm' is the next word boundary in the forward direction from one-past 'r'
// - 'f' is the next word boundary in the backward direction from 'oobar'
// - 'f' is the next word boundary in the backward direction from one-past 'r'
//
// +------------------------+--------------+--------------+
// | | pFP:toBo:fwd | pFP:toBo:bwd |
// +------------------------+--------------+--------------+
// | 'f' | one-past 'r' | nil |
// | 'oobar' | one-past 'r' | 'f' |
// | one-past 'r' | 'm' | 'f' |
// +------------------------+--------------+--------------+
//
// - for 'f', the enclosing range is nil in the backward direction, and is 'foobar' in the forward direction
// - for 'oobar', the enclosing range in the forward and backward direction is 'foobar'
// - for one-past 'r', the enclosing range is nil in the forward direction, and is 'foobar' in the backward direction
//
// +---------------------+--------------+--------------+
// | | range:wG:fwd | range:wG:bwd |
// +---------------------+--------------+--------------+
// | 'f' | 'foobar' | nil |
// | 'oobar' | 'foobar' | 'foobar' |
// | one-past 'r' | nil | 'foobar' |
// +---------------------+--------------+--------------+
@interface NKTTextViewTokenizer()
#pragma mark Determining Text Positions Relative to Unit Boundaries
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition atWordBoundaryInDirection:(UITextDirection)direction;
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition atLineBoundaryInDirection:(UITextDirection)direction;
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition atParagraphBoundaryInDirection:(UITextDirection)direction;
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition withinWordInDirection:(UITextDirection)direction;
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition withinLineInDirection:(UITextDirection)direction;
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition withinParagraphInDirection:(UITextDirection)direction;
#pragma mark Computing Text Position by Unit Boundaries
- (UITextPosition *)positionFromTextPosition:(NKTTextPosition *)textPosition
toWordBoundaryInDirection:(UITextDirection)direction;
- (UITextPosition *)positionFromTextPosition:(NKTTextPosition *)textPosition
toLineBoundaryInDirection:(UITextDirection)direction;
- (UITextPosition *)positionFromTextPosition:(NKTTextPosition *)textPosition
toParagraphBoundaryInDirection:(UITextDirection)direction;
#pragma mark Getting Ranges of Specific Text Units
- (UITextRange *)textRangeForWordEnclosingTextPosition:(NKTTextPosition *)textPosition
inDirection:(UITextDirection)direction;
@end
#pragma mark -
//--------------------------------------------------------------------------------------------------
@implementation NKTTextViewTokenizer
#pragma mark Initializing
- (id)initWithTextView:(NKTTextView *)textView
{
if ((self = [super initWithTextInput:textView]))
{
textView_ = textView;
}
return self;
}
//--------------------------------------------------------------------------------------------------
#pragma mark Determining Text Positions Relative to Unit Boundaries
- (BOOL)isPosition:(NKTTextPosition *)textPosition
atBoundary:(UITextGranularity)granularity
inDirection:(UITextDirection)direction
{
BOOL result = NO;
if (granularity == UITextGranularityWord)
{
result = [self isTextPosition:textPosition atWordBoundaryInDirection:direction];
}
else if (granularity == UITextGranularityLine)
{
result = [self isTextPosition:textPosition atLineBoundaryInDirection:direction];
}
else if (granularity == UITextGranularityParagraph)
{
result = [self isTextPosition:textPosition atParagraphBoundaryInDirection:direction];
}
else
{
result = [super isPosition:textPosition atBoundary:granularity inDirection:direction];
}
KBCLogDebug(@"%d : %@ : %@ -> %d",
textPosition.location,
KBTStringFromUITextGranularity(granularity),
KBTStringFromUITextDirection(direction),
result);
return result;
}
// A text position is a word boundary in the forward direction if the text position is the end of
// a word.
//
// A text position is a word boundary in the backward direction if the text position is the start
// of a word.
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition atWordBoundaryInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NSCharacterSet *alphanumerics = [NSCharacterSet alphanumericCharacterSet];
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
// Not end of word if index is 0
if (textPosition.location == 0)
{
return NO;
}
// End of word if previous position is alphanumeric, and position is not alphanumeric
unichar previousChar = [string characterAtIndex:textPosition.location - 1];
if (textPosition.location == [string length])
{
return [alphanumerics characterIsMember:previousChar];
}
unichar theChar = [string characterAtIndex:textPosition.location];
return [alphanumerics characterIsMember:previousChar] && ![alphanumerics characterIsMember:theChar];
}
else
{
// Not start of word if index is the end
if (textPosition.location == [string length])
{
return NO;
}
// Start of word if previous position is not alphanumeric and position is alphanumeric
unichar theChar = [string characterAtIndex:textPosition.location];
if (textPosition.location == 0)
{
return [alphanumerics characterIsMember:theChar];
}
unichar previousChar = [string characterAtIndex:textPosition.location - 1];
return [alphanumerics characterIsMember:theChar] && ![alphanumerics characterIsMember:previousChar];
}
}
// A text position is a line boundary in the forward direction if the text position is one before
// the end of a line's text range.
//
// A text position is a line boundary in the backward direction if the text position is the start
// of a line's text range.
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition atLineBoundaryInDirection:(UITextDirection)direction
{
NKTTextRange *lineTextRange = [textView_ textRangeForLineContainingTextPosition:textPosition];
if (lineTextRange == nil)
{
return NO;
}
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
return [textPosition isEqualToTextPosition:[lineTextRange.end textPositionByApplyingOffset:-1]];
}
else
{
return [textPosition isEqualToTextPosition:lineTextRange.start];
}
}
// A text position is a paragraph boundary in the forward direction if the text position is the
// end of a paragraph (newline).
//
// A text position is a paragraph boundary in the backward direction if the text position is the
// start of a paragraph (follows a newline).
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition atParagraphBoundaryInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NSCharacterSet *newlines = [NSCharacterSet newlineCharacterSet];
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
// End index is always ends a paragraph
if (textPosition.location == [string length])
{
return YES;
}
// End of paragraph if position is a newline
unichar theChar = [string characterAtIndex:textPosition.location];
return [newlines characterIsMember:theChar];
}
else
{
// Start index always begins a paragraph
if (textPosition.location == 0)
{
return YES;
}
// Start of paragraph if previous position is a newline
unichar previousChar = [string characterAtIndex:textPosition.location - 1];
return [newlines characterIsMember:previousChar];
}
}
- (BOOL)isPosition:(NKTTextPosition *)textPosition withinTextUnit:(UITextGranularity)granularity inDirection:(UITextDirection)direction
{
BOOL result = NO;
if (granularity == UITextGranularityWord)
{
result = [self isTextPosition:textPosition withinWordInDirection:direction];
}
else if (granularity == UITextGranularityLine)
{
result = [self isTextPosition:textPosition withinLineInDirection:direction];
}
else if (granularity == UITextGranularityParagraph)
{
result = [self isTextPosition:textPosition withinParagraphInDirection:direction];
}
else
{
result = [super isPosition:textPosition withinTextUnit:granularity inDirection:direction];
}
KBCLogDebug(@"%d : %@ : %@ -> %d",
textPosition.location,
KBTStringFromUITextGranularity(granularity),
KBTStringFromUITextDirection(direction),
result);
return result;
}
// A text position is within a word in the forward direction if the text position is part of a
// word.
//
// A text position is within a word in the backward direction if the previous text position is part
// of a word.
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition withinWordInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NSCharacterSet *alphanumerics = [NSCharacterSet alphanumericCharacterSet];
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
// No words beyond the end index
if (textPosition.location == [string length])
{
return NO;
}
unichar theChar = [string characterAtIndex:textPosition.location];
return [alphanumerics characterIsMember:theChar];
}
else
{
// No words before the start index
if (textPosition.location == 0)
{
return NO;
}
unichar previousChar = [string characterAtIndex:textPosition.location - 1];
return [alphanumerics characterIsMember:previousChar];
}
}
// If the line containing a text position has a text range with a length equal to one, then the
// text position is a boundary in both the forward and backward direction. Otherwise, the
// following applies:
//
// A text position is within a line in the forward direction if the text position is not the
// position one before the end of a line's text range.
//
// A text position is within a line in the backward direction if the text position is not the
// start of a line's text range.
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition withinLineInDirection:(UITextDirection)direction
{
NKTTextRange *lineTextRange = [textView_ textRangeForLineContainingTextPosition:textPosition];
if (lineTextRange == nil)
{
return NO;
}
if (lineTextRange.length == 1)
{
return YES;
}
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
return ![textPosition isEqualToTextPosition:[lineTextRange.end textPositionByApplyingOffset:-1]];
}
else
{
return ![textPosition isEqualToTextPosition:lineTextRange.start];
}
}
// A text position is within a paragraph in the forward direction if the text position is not the
// end of a paragraph (newline).
//
// A text position is within a paragraph in the backward direction if the text position is not the
// start of a paragraph (follows a newline).
- (BOOL)isTextPosition:(NKTTextPosition *)textPosition withinParagraphInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NSCharacterSet *newlines = [NSCharacterSet newlineCharacterSet];
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
// End index is always end of a paragraph
if (textPosition.location == [string length])
{
return NO;
}
unichar theChar = [string characterAtIndex:textPosition.location];
return ![newlines characterIsMember:theChar];
}
else
{
// Start index is always start of a paragraph
if (textPosition.location == 0)
{
return NO;
}
unichar previousChar = [string characterAtIndex:textPosition.location - 1];
return ![newlines characterIsMember:previousChar];
}
}
//--------------------------------------------------------------------------------------------------
#pragma mark Computing Text Position by Unit Boundaries
- (UITextPosition *)positionFromPosition:(NKTTextPosition *)textPosition
toBoundary:(UITextGranularity)granularity
inDirection:(UITextDirection)direction
{
UITextPosition *boundaryTextPosition = nil;
if (granularity == UITextGranularityWord)
{
boundaryTextPosition = [self positionFromTextPosition:textPosition toWordBoundaryInDirection:direction];
}
else if (granularity == UITextGranularityLine)
{
boundaryTextPosition = [self positionFromTextPosition:textPosition toLineBoundaryInDirection:direction];
}
else if (granularity == UITextGranularityParagraph)
{
boundaryTextPosition = [self positionFromTextPosition:textPosition toParagraphBoundaryInDirection:direction];
}
else
{
boundaryTextPosition = [super positionFromPosition:textPosition toBoundary:granularity inDirection:direction];
}
KBCLogDebug(@"%d : %@ : %@ -> %d",
textPosition.location,
KBTStringFromUITextGranularity(granularity),
KBTStringFromUITextDirection(direction),
((NKTTextPosition *)boundaryTextPosition).location);
return boundaryTextPosition;
}
// The next word boundary in the forward direction is the furthest position in the direction that
// has the opposite alphanumeric 'sign' as the given position.
//
// The next word boundary in the backward direction is the furthest position in the direction that
// has the same alphanumeric 'sign' as the given position.
- (UITextPosition *)positionFromTextPosition:(NKTTextPosition *)textPosition
toWordBoundaryInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NSCharacterSet *alphanumerics = [NSCharacterSet alphanumericCharacterSet];
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
// The end position is always treated as a word boundary
if (textPosition.location == [string length])
{
return textPosition;
}
unichar referenceChar = [string characterAtIndex:textPosition.location];
BOOL referenceCharSign = [alphanumerics characterIsMember:referenceChar];
NSUInteger currentIndex = textPosition.location + 1;
for (; currentIndex < [string length]; ++currentIndex)
{
unichar currentChar = [string characterAtIndex:currentIndex];
BOOL currentCharSign = [alphanumerics characterIsMember:currentChar];
if (referenceCharSign != currentCharSign)
{
break;
}
}
return [NKTTextPosition textPositionWithLocation:currentIndex affinity:UITextStorageDirectionForward];
}
else
{
// The start position is always treated a word boundary
if (textPosition.location == 0)
{
return textPosition;
}
unichar referenceChar = [string characterAtIndex:textPosition.location - 1];
BOOL referenceCharSign = [alphanumerics characterIsMember:referenceChar];
NSUInteger currentIndex = textPosition.location - 1;
for (; currentIndex > 0; --currentIndex)
{
unichar currentChar = [string characterAtIndex:currentIndex];
BOOL currentCharSign = [alphanumerics characterIsMember:currentChar];
if (referenceCharSign != currentCharSign)
{
++currentIndex;
break;
}
}
return [NKTTextPosition textPositionWithLocation:currentIndex affinity:UITextStorageDirectionForward];
}
}
// If the text position is one before the end of a line's text range, it is already at the
// boundary. Otherwise, the next line boundary in the forward direction is one before the
// end of the line's text range.
//
// If the text position is the start of a line's text range, it is already at the boundary.
// Otherwise, the next line boundary in the backward direction is the start of the line's text
// range.
- (UITextPosition *)positionFromTextPosition:(NKTTextPosition *)textPosition
toLineBoundaryInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NKTTextRange *lineTextRange = [textView_ textRangeForLineContainingTextPosition:textPosition];
if (lineTextRange == nil)
{
return nil;
}
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
// PENDING: No boundary position after the end index?
if (textPosition.location == [string length])
{
return textPosition;
}
NKTTextPosition *oneBeforeEnd = [lineTextRange.end textPositionByApplyingOffset:-1];
if ([textPosition isEqualToTextPosition:oneBeforeEnd])
{
// HACK: make sure that UITextInput does not 'skip' over a line
return textPosition;
}
else
{
return oneBeforeEnd;
}
}
else
{
// No boundary position before the start index
if (textPosition.location == 0)
{
return textPosition;
}
if ([textPosition isEqualToTextPosition:lineTextRange.start])
{
// HACK: make sure that UITextInput does not 'skip' over a line
return textPosition;
}
else
{
return lineTextRange.start;
}
}
}
// If the text position is the end of a paragraph, the next paragraph boundary in the
// forward direction is one beyond the end of the paragraph. Otherwise, the next paragraph
// boundary in the forward direction is one before the end of the paragraph.
//
// If the text position is the start of a paragraph, the next paragraph boundary in the backward
// direction is one before the start of the paragraph. Otherwise, the next paragraph boundary in
// the backward direction is the start of the paragraph.
- (UITextPosition *)positionFromTextPosition:(NKTTextPosition *)textPosition
toParagraphBoundaryInDirection:(UITextDirection)direction
{
NSString *string = [textView_.text string];
NSCharacterSet *newlines = [NSCharacterSet newlineCharacterSet];
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
if (textPosition.location == [string length])
{
return textPosition;
}
unichar theChar = [string characterAtIndex:textPosition.location];
if ([newlines characterIsMember:theChar])
{
return [textPosition textPositionByApplyingOffset:+1];
}
else
{
NSUInteger currentIndex = textPosition.location + 1;
for (; currentIndex < [string length]; ++currentIndex)
{
unichar currentChar = [string characterAtIndex:currentIndex];
if ([newlines characterIsMember:currentChar])
{
break;
}
}
return [NKTTextPosition textPositionWithLocation:currentIndex affinity:UITextStorageDirectionForward];
}
}
else
{
if (textPosition.location == 0)
{
return textPosition;
}
unichar previousChar = [string characterAtIndex:textPosition.location - 1];
if ([newlines characterIsMember:previousChar])
{
return [textPosition textPositionByApplyingOffset:-1];
}
else
{
NSUInteger currentIndex = textPosition.location - 1;
for (; currentIndex > 0; --currentIndex)
{
unichar currentChar = [string characterAtIndex:currentIndex];
if ([newlines characterIsMember:currentChar])
{
++currentIndex;
break;
}
}
return [NKTTextPosition textPositionWithLocation:currentIndex affinity:UITextStorageDirectionForward];
}
}
}
//--------------------------------------------------------------------------------------------------
#pragma mark Getting Ranges of Specific Text Units
// In this method, return the range for the text enclosing a text position in a text unit of the
// given granularity, or nil if there is no such enclosing unit. If the text position is entirely
// enclosed within a text unit of the given granularity, it is considered enclosed. If the text
// position is at a text-unit boundary, it is considered enclosed only if the next position in
// the given direction is entirely enclosed.
- (UITextRange *)rangeEnclosingPosition:(NKTTextPosition *)textPosition
withGranularity:(UITextGranularity)granularity
inDirection:(UITextDirection)direction
{
UITextRange *result = nil;
// if (granularity == UITextGranularityWord)
// {
// result = [self textRangeForWordEnclosingTextPosition:textPosition inDirection:direction];
// }
// else if (granularity == UITextGranularityLine)
// {
// // PENDING: it looks like this is never used, so leave it unimplemented for now
// result = nil;
// }
// else
// {
result = [super rangeEnclosingPosition:textPosition withGranularity:granularity inDirection:direction];
// }
KBCLogDebug(@"%d : %@ : %@ : %@",
textPosition.location,
KBTStringFromUITextGranularity(granularity),
KBTStringFromUITextDirection(direction),
result);
return result;
}
- (UITextRange *)textRangeForWordEnclosingTextPosition:(NKTTextPosition *)textPosition
inDirection:(UITextDirection)direction
{
if (direction == UITextStorageDirectionForward ||
direction == UITextLayoutDirectionRight ||
direction == UITextLayoutDirectionDown)
{
if (![self isTextPosition:textPosition withinWordInDirection:UITextStorageDirectionForward])
{
return nil;
}
NKTTextPosition *backwardBoundary = nil;
if ([self isTextPosition:textPosition atWordBoundaryInDirection:UITextStorageDirectionBackward])
{
backwardBoundary = textPosition;
}
else
{
backwardBoundary = (NKTTextPosition *)[self positionFromTextPosition:textPosition
toWordBoundaryInDirection:UITextStorageDirectionBackward];
}
NKTTextPosition *forwardBoundary = nil;
if ([self isTextPosition:textPosition atWordBoundaryInDirection:UITextStorageDirectionForward])
{
forwardBoundary = textPosition;
}
else
{
forwardBoundary = (NKTTextPosition *)[self positionFromTextPosition:textPosition
toWordBoundaryInDirection:UITextStorageDirectionForward];
}
return [NKTTextRange textRangeWithTextPosition:backwardBoundary textPosition:forwardBoundary];
}
else
{
if (![self isTextPosition:textPosition withinWordInDirection:UITextStorageDirectionBackward])
{
return nil;
}
NKTTextPosition *backwardBoundary = nil;
if ([self isTextPosition:textPosition atWordBoundaryInDirection:UITextStorageDirectionBackward])
{
backwardBoundary = textPosition;
}
else
{
backwardBoundary = (NKTTextPosition *)[self positionFromTextPosition:textPosition
toWordBoundaryInDirection:UITextStorageDirectionBackward];
}
NKTTextPosition *forwardBoundary = nil;
if ([self isTextPosition:textPosition atWordBoundaryInDirection:UITextStorageDirectionForward])
{
forwardBoundary = textPosition;
}
else
{
forwardBoundary = (NKTTextPosition *)[self positionFromTextPosition:textPosition
toWordBoundaryInDirection:UITextStorageDirectionForward];
}
return [NKTTextRange textRangeWithTextPosition:backwardBoundary textPosition:forwardBoundary];
}
}
@end
@allending
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FYI, the UITextInputTokenizer docs melt my brain.

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