711/BuguLive/Class/Sections/FWFreshMeat/MenuCenter/Dynamic/STUI/STTableCell/STTableTextViewCell/STTableTextViewCell.m

//
//  STTableTextViewCell.m
//  BuguLive
//
//  Created by 岳克奎 on 17/4/18.
//  Copyright © 2017年 xfg. All rights reserved.
//

#import "STTableTextViewCell.h"

@implementation STTableTextViewCell

- (void)awakeFromNib {
    [super awakeFromNib];
    // Initialization code
    //初始化部分
    [self setSubView];
//    self.textView.textColor = kBlackColor;
}
#pragma mark - 初始化部分
-(void)setSubView{
    self.textView.delegate = self;
}
#pragma mark ------将要开始编辑
-(BOOL)textViewShouldBeginEditing:(UITextView *)textView{
    if ([textView.text isEqualToString: ASLocalizedString(@"这一刻你的想法")]) {
        textView.text = @"";
        textView.textColor = kBlackColor;
    }
    return YES;
}
#pragma mark -将要结束编辑
-(BOOL)textViewShouldEndEditing:(UITextView *)textView{
    return YES;
}
#pragma mark -开始编辑
-(void)textViewDidBeginEditing:(UITextView *)textView{
    
}
#pragma mark -结束编辑
/**
 * @brief: 结束编辑,需要回传数据
 *
 *
 */

-(void)textViewDidEndEditing:(UITextView *)textView{
    if (textView.text.length == 0) {
        textView.text = ASLocalizedString(@"这一刻你的想法");
        textView.textColor = [UIColor colorWithHexString:@"#ABABAB"];
    }
    if (_delegate &&[_delegate respondsToSelector:@selector(showSTTableTextViewCell:)]) {
        [_delegate showSTTableTextViewCell:self];
    }
}
#pragma mark -内容将要发生改变编辑
-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
    //不支持系统表情的输入
    if ([[textView textInputMode] primaryLanguage]==nil||[[[textView textInputMode] primaryLanguage]isEqualToString:@"emoji"]) {
        return NO;
    }
    UITextRange *selectedRange = [textView markedTextRange];
    //获取高亮部分
    UITextPosition *pos = [textView positionFromPosition:selectedRange.start offset:0];
    if (selectedRange && pos) {
        NSInteger startOffset = [textView offsetFromPosition:textView.beginningOfDocument toPosition:selectedRange.start];
        NSInteger endOffset = [textView offsetFromPosition:textView.beginningOfDocument toPosition:selectedRange.end];
        NSRange offsetRange =NSMakeRange(startOffset, endOffset - startOffset);
        if (offsetRange.location <MAX_LIMIT_NUMS) {
            return YES;
        }else{
            return NO;
        }
    }
    NSString *comcatstr = [textView.text stringByReplacingCharactersInRange:range withString:text];
    NSInteger caninputlen =MAX_LIMIT_NUMS - comcatstr.length;
    if (caninputlen >=0){
        return YES;
    }else{
        NSInteger len = text.length + caninputlen;
        //防止当text.length + caninputlen < 0时，使得rg.length为一个非法最大正数出错
        NSRange rg = {0,MAX(len,0)};
        if (rg.length >0){
            NSString *s =@"";
            //判断是否只普通的字符或asc码(对于中文和表情返回NO)
            BOOL asc = [text canBeConvertedToEncoding:NSASCIIStringEncoding];
            if (asc) {
                s = [text substringWithRange:rg];//因为是ascii码直接取就可以了不会错
            }else{
                __block NSInteger idx =0;
                __block NSString  *trimString =@"";//截取出的字串
                //使用字符串遍历，这个方法能准确知道每个emoji是占一个unicode还是两个
                [text enumerateSubstringsInRange:NSMakeRange(0, [text length])
                                         options:NSStringEnumerationByComposedCharacterSequences
                                      usingBlock: ^(NSString* substring,NSRange substringRange,NSRange enclosingRange,BOOL* stop) {
                                          if (idx >= rg.length) {
                                              *stop =YES;//取出所需要就break，提高效率
                                              return ;
                                          }
                                          trimString = [trimString stringByAppendingString:substring];
                                          idx++;
                                      }];
                s = trimString;
            }
            //rang是指从当前光标处进行替换处理(注意如果执行此句后面返回的是YES会触发didchange事件)
            [textView setText:[textView.text stringByReplacingCharactersInRange:range withString:s]];
            //既然是超出部分截取了，哪一定是最大限制了。
            //self.showWordsNumLab.text = [NSString stringWithFormat:@"%d/%ld",0,(long)MAX_LIMIT_NUMS];
            self.showWordsNumLab.text = @"100/100";
        }
        return NO;
    }
    return YES;
}
#pragma mark -内容发生改变编辑（-显示当前可输入字数/总字数）
-(void)textViewDidChange:(UITextView *)textView{
    UITextRange *selectedRange = [textView markedTextRange];
    //获取高亮部分
    UITextPosition *pos = [textView positionFromPosition:selectedRange.start offset:0];
    //如果在变化中是高亮部分在变，就不要计算字符了
    if (selectedRange && pos) {
        return;
    }
    NSString  *nsTextContent = textView.text;
    NSInteger existTextNum = nsTextContent.length;
    if (existTextNum >MAX_LIMIT_NUMS){
        //截取到最大位置的字符(由于超出截部分在should时被处理了所在这里这了提高效率不再判断)
        NSString *s = [nsTextContent substringToIndex:MAX_LIMIT_NUMS];
        [textView setText:s];
    }
    //不让显示负数
    self.showWordsNumLab.text = [NSString stringWithFormat:@"%ld/100",  existTextNum];

//    self.showWordsNumLab.text = [NSString stringWithFormat:@"%ld/100",(MAX_LIMIT_NUMS - existTextNum)];
    
    //self.showWordsNumLab.text = [NSString stringWithFormat:@"%ld/%d",MAX(0,MAX_LIMIT_NUMS - existTextNum),MAX_LIMIT_NUMS];
}
#pragma mark ************************** Setter *************************
#pragma mark -- STTableTextViewCellDeleagte
-(void)setDelegate:(id<STTableTextViewCellDeleagte>)delegate{
    _delegate = delegate;
}
- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
    [super setSelected:selected animated:animated];
    
    // Configure the view for the selected state
}

@end