iOS高仿微信表情输入功能代码分享

//富文本
WKExpressionTextAttachment *attachment = [[WKExpressionTextAttachment alloc] initWithData:nil ofType:nil];
UIImage *image = [UIImage imageNamed:imageName];
attachment.image = image;
attachment.text = [WKExpressionTool getExpressionStringWithImageName:imageName];
attachment.bounds = CGRectMake(0, 0, fontSize, fontSize);
NSAttributedString *insertAttributeStr = [NSAttributedString attributedStringWithAttachment:attachment];
NSMutableAttributedString *resultAttrString = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];
//在当前编辑位置插入字符串
[resultAttrString insertAttributedString:insertAttributeStr atIndex:self.selectedRange.location];
NSRange tempRange = self.selectedRange;
self.attributedText = resultAttrString;
self.selectedRange = NSMakeRange(tempRange.location + 1, 0);
[self.textStorage addAttributes:@{NSFontAttributeName : [UIFont systemFontOfSize:_defaultFontSize]} range:NSMakeRange(0, self.attributedText.length)];
[self scrollRangeToVisible:self.selectedRange];
[self textChanged];

@interface WKExpressionTextAttachment : NSTextAttachment
@property (nonatomic, copy) NSString *text;
@end

+ (NSAttributedString *)generateAttributeStringWithOriginalString:(NSString *)originalString fontSize:(CGFloat)fontSize
{
NSError *error = NULL;
NSMutableAttributedString *resultAttrString = [[NSMutableAttributedString alloc] initWithString:originalString];
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"\\[[a-zA-Z0-9\u4e00-\u9fa5]{1,}\\]" options:NSRegularExpressionAllowCommentsAndWhitespace error:&error];
NSArray *results = [regex matchesInString:originalString options:NSMatchingReportCompletion range:NSMakeRange(0, originalString.length)];
if (results) {
for (NSTextCheckingResult *result in results.reverseObjectEnumerator) {
NSRange resultRange = [result rangeAtIndex:0];
NSString *stringResult = [originalString substringWithRange:resultRange];
NSLog(@"%s %@\n", __FUNCTION__, stringResult);
NSAttributedString *expressionAttrString = [self getAttributeStringWithExpressionString:stringResult fontSize:fontSize];
[resultAttrString replaceCharactersInRange:resultRange withAttributedString:expressionAttrString];
}
}
return resultAttrString;
}

/**
* 通过表情生成富文本
*
* @param expressionString 表情名
* @param fontSize 对应字体大小
*
* @return 富文本
*/
+ (NSAttributedString *)getAttributeStringWithExpressionString:(NSString *)expressionString fontSize:(CGFloat)fontSize
{
NSString *imageName = [self getExpressionStringWithImageName:expressionString];
WKExpressionTextAttachment *attachment = [[WKExpressionTextAttachment alloc] initWithData:nil ofType:nil];
UIImage *image = [UIImage imageNamed:imageName];
attachment.image = image;
attachment.text = [WKExpressionTool getExpressionStringWithImageName:imageName];
attachment.bounds = CGRectMake(0, 0, fontSize, fontSize);
NSAttributedString *appendAttributeStr = [NSAttributedString attributedStringWithAttachment:attachment];
return appendAttributeStr;
}

- (void)copy:(id)sender
{
NSAttributedString *selectedString = [self.attributedText attributedSubstringFromRange:self.selectedRange];
NSString *copyString = [self parseAttributeTextToNormalString:selectedString];
UIPasteboard *pboard = [UIPasteboard generalPasteboard];
if (copyString.length != 0) {
pboard.string = copyString;
}
}
- (void)cut:(id)sender
{
[self copy:sender];
NSMutableAttributedString *originalString = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];
[originalString deleteCharactersInRange:self.selectedRange];
self.attributedText = originalString;
NSLog(@"--%@", NSStringFromRange(self.selectedRange));
[self textChanged];
}

@interface WKExpressionTextView : UITextView
@property (nonatomic, assign) CGFloat defaultFontSize;
@end
@implementation WKExpressionTextView
{
CGFloat _defaultFontSize;
}
- (void)awakeFromNib
{
[self setup];
}
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self setup];
}
return self;
}
- (void)setup
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textChange:) name:UITextViewTextDidChangeNotification object:self];
_defaultFontSize = self.font.pointSize;
self.delegate = self;
}