Created
February 1, 2011 08:07
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Some expository code from Notekata as a UITextInputTokenizer example
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| //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 |
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| //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 |
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There's hardly anything in them! Shoutout for the best reference I could find on how to implement this interface, it help resolved some virtual keyboard issues in our notes app https://github.com/lockbook/lockbook