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copied!<p>The <code>UITextInput</code> protocol includes a <code>beginningOfDocument</code> selector since iOS 3.2.<br> But <code>UITextView</code> only adopted <code>UITextInput</code> since iOS 5.0. It was previously conforming to the <code>UITextInputTraits</code> protocol.</p> <p>Source: search for UITextView here <a href="http://developer.apple.com/library/ios/#releasenotes/General/iOS50APIDiff/index.html" rel="nofollow">http://developer.apple.com/library/ios/#releasenotes/General/iOS50APIDiff/index.html</a></p> <p>If you want it to work on iOS 4.x and later, you have to perform a check and do the computation by yourself on iOS 4:</p> <pre><code>CGRect newRect = CGRectZero; if ([UITextView conformsToProtocol:@protocol(UITextInput)]) { // iOS 5 and later UITextPosition *begin = [self.tvQuestion positionFromPosition:self.tvQuestion.beginningOfDocument offset:nrange.location]; UITextPosition *end = [self.tvQuestion positionFromPosition:begin offset:nrange.length]; UITextRange *textRange = [self.tvQuestion textRangeFromPosition:begin toPosition:end]; newRect = [self.tvQuestion firstRectForRange:textRange]; } else { // iOS 3.2 to 4.3 // Compute text position manually #define TEXT_VIEW_PADDING 8.f NSString *textContent = [self.tvQuestion.text substringToIndex:NSMaxRange(nrange)]; NSDictionary *ctFontDescriptorAttributes = [NSDictionary dictionaryWithObjectsAndKeys: self.tvQuestion.font.familyName, kCTFontFamilyNameAttribute, // Uncomment for bold fonts // [NSDictionary dictionaryWithObjectsAndKeys: // [NSNumber numberWithInt:kCTFontBoldTrait], kCTFontSymbolicTrait, // nil], kCTFontTraitsAttribute, nil]; CTFontDescriptorRef ctFontDescriptor = CTFontDescriptorCreateWithAttributes((CFDictionaryRef)ctFontDescriptorAttributes); CTFontRef ctFont = CTFontCreateWithFontDescriptor(ctFontDescriptor, self.tvQuestion.font.pointSize, NULL); NSAttributedString *attributedText = [[NSAttributedString alloc] initWithString:textContent attributes:[NSDictionary dictionaryWithObjectsAndKeys: (id)ctFont, kCTFontAttributeName, nil]]; CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)attributedText); CFRange globalRange = CFRangeMake(0, [attributedText length]); CGRect textRect = CGRectInset((CGRect){CGPointZero, self.tvQuestion.contentSize}, TEXT_VIEW_PADDING, TEXT_VIEW_PADDING); CTFrameRef frame = CTFramesetterCreateFrame(framesetter, globalRange, CGPathCreateWithRect((CGRect){CGPointZero, textRect.size}, NULL), NULL); CFArrayRef lines = CTFrameGetLines(frame); NSInteger nbLines = CFArrayGetCount(lines); CGPoint *lineOrigins = calloc(sizeof(CGPoint), nbLines); CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), lineOrigins); CGFloat ascent = CTFontGetAscent(ctFont); CGFloat descent = CTFontGetDescent(ctFont); CGFloat leading = CTFontGetLeading(ctFont); if (leading < 0) { leading = 0; } leading = floor(leading + 0.5); CGFloat lineHeight = floor(ascent + 0.5) + floor(descent + 0.5) + leading; CGFloat firstLineYOffset = 0.f; for (NSInteger i = 0; i < nbLines; i++) { CTLineRef line = CFArrayGetValueAtIndex(lines, i); CFRange lineRange = CTLineGetStringRange(line); CGPoint lineOrigin = lineOrigins[i]; CGFloat ascent, descent, leading, width; width = CTLineGetTypographicBounds(line, &ascent, &descent, &leading); if (i == 0) { firstLineYOffset = lineOrigin.y; } lineOrigin.y = (lineOrigin.y - firstLineYOffset) * -1.f; if (nrange.location >= lineRange.location && nrange.location < lineRange.location + lineRange.length) { CGFloat secOffset; CGFloat startOffset = CTLineGetOffsetForStringIndex(line, nrange.location, &secOffset); CGFloat rectWidth; if (nrange.location + nrange.length <= lineRange.location + lineRange.length) { CGFloat endOffset = CTLineGetOffsetForStringIndex(line, nrange.location + nrange.length, &secOffset); rectWidth = endOffset - startOffset; } else { rectWidth = width - 5 - startOffset; } newRect = (CGRect) { { lineOrigin.x + TEXT_VIEW_PADDING + startOffset, lineOrigin.y + TEXT_VIEW_PADDING + i }, { rectWidth, lineHeight } }; break; } } free(lineOrigins); CFRelease(frame); CFRelease(framesetter); CFRelease(ctFont); CFRelease(ctFontDescriptor); } </code></pre>

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