YYTextView 的基本使用 及 字数限制

• podfile 导入文件库

platform :ios, '9.0'
target '项目名' do
pod 'YYText'
end

#import "YYTextView.h"  //引入头文件
//文字输入内容 设置属性
@property (nonatomic, strong) YYTextView *contentTextView;


/** 内容视图 */ //懒加载
- (YYTextView *)contentTextView{
    if (_contentTextView == nil) {
        _contentTextView = [[YYTextView alloc]init];
                
//        _contentTextView.extraAccessoryViewHeight = 100; //键盘弹出时这个 会 自动 便宜的 一个 属性
        _contentTextView.placeholderText = @"宝贝满足你的期待值么？说说你的使用心得，分享给想买的他 们吧";
        _contentTextView.placeholderFont = [UIFont pingFangSCWithWeight:PFFontWeightStyleRegular size:15];
        _contentTextView.placeholderTextColor = HEX(0x999999);

        _contentTextView.font = [UIFont pingFangSCWithWeight:PFFontWeightStyleRegular size:15];
        _contentTextView.textColor = HEX(0x333333);

        _contentTextView.delegate = self;

//        [_contentTextView becomeFirstResponder];
    }
    return _contentTextView;
}

//
   [self.view addSubview:self.contentTextView];

//添加字数统计观察者
    [self addObserver];

#pragma mark 关键方法 YYTextView 字数监听 添加通知
-(void)addObserver{
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textViewDidChangeNotification:) name:YYTextViewTextDidChangeNotification object:self.contentTextView];
}
//移除通知
- (void)dealloc{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

//字数限制  200 字
-(void)textViewDidChangeNotification:(NSNotification *)obj{
    YYTextView *textView = (YYTextView *)obj.object;
    NSString *string = textView.text;
    NSInteger maxLength = 200;
    //获取高亮部分
    YYTextRange *selectedRange = [textView valueForKey:@"_markedTextRange"];
    NSRange range = [selectedRange asRange];
    NSString *realString = [string substringWithRange:NSMakeRange(0, string.length - range.length)];
    if (realString.length >= maxLength){
        textView.text = [realString substringWithRange:NSMakeRange(0, maxLength)];
    }
}