由于項(xiàng)目中許多地方用到textView，并且要有placeholder和自動(dòng)計(jì)數(shù)、字?jǐn)?shù)限制，所以自己就想著寫(xiě)一個(gè)，可以方便很多地方調(diào)用。

演示.gif

1.先新建一個(gè)繼承UITextView的文件，主要是在這里實(shí)現(xiàn)placeholder、clearButton以及自動(dòng)計(jì)數(shù)控件的通用類設(shè)置，還有一些代理方法:

@property (nonatomic, strong) NSString *placeholder;
@property (nonatomic, strong) UIColor *placeholderColor;
@property (nonatomic, strong) UIFont *placeholderFont;

//允許輸入的最大長(zhǎng)度
@property (nonatomic, assign) NSInteger maxLength;
//是否顯示 計(jì)數(shù)器 label
@property (nonatomic, assign) BOOL showWordCountLabel;

-(void)setPlaceholder:(NSString *)placeholder
{
    _placeholder = placeholder;
    [self setNeedsDisplay];
}

-(void)setPlaceholderFont:(UIFont *)placeholderFont
{
    _placeholderFont = placeholderFont;
    [self setNeedsDisplay];
}

-(void)setPlaceholderColor:(UIColor *)placeholderColor
{
    _placeholderColor = placeholderColor;
    [self setNeedsDisplay];
}

2.建一個(gè)繼承UIView的文件，在這里設(shè)置屬性和回調(diào)方法，把上面創(chuàng)建的頭文件導(dǎo)入進(jìn)來(lái)，如下方法：

-(void)textViewDidChange:(UITextView *)textView
{
    [self textViewTextLengthChange:textView.text.length];
    
    self.maxTextCount = 60;
    
    NSString *toBeString = textView.text;
    
    NSString *lang = [(UITextInputMode*)[[UITextInputMode activeInputModes] firstObject] primaryLanguage]; // 鍵盤(pán)輸入模式
    if ([lang isEqualToString:@"zh-Hans"]) { // 簡(jiǎn)體中文輸入，包括簡(jiǎn)體拼音，健體五筆，簡(jiǎn)體手寫(xiě)
        UITextRange *selectedRange = [textView markedTextRange];
        //獲取高亮部分
        UITextPosition *position = [textView positionFromPosition:selectedRange.start offset:0];
        // 沒(méi)有高亮選擇的字，則對(duì)已輸入的文字進(jìn)行字?jǐn)?shù)統(tǒng)計(jì)和限制
        if (!position) {
            if (toBeString.length >= self.maxTextCount) {
                textView.text = [toBeString substringToIndex:self.maxTextCount];
            }
            self.countLabel.text=[NSString stringWithFormat:@"(%lu/%@)",(unsigned long)_textView.text.length, @(self.maxTextCount)];
            [self changeTextWithTextColor:[UIColor orangeColor] OfLabel:self.countLabel withLocation:1 andLength:self.countLabel.text.length-5];
            
            
        } // 有高亮選擇的字符串，則暫不對(duì)文字進(jìn)行統(tǒng)計(jì)和限制
        else{
            
        }
    }
    // 中文輸入法以外的直接對(duì)其統(tǒng)計(jì)限制即可，不考慮其他語(yǔ)種情況
    else{
        if (toBeString.length >= self.maxTextCount) {
            textView.text = [toBeString substringToIndex:self.maxTextCount];
        }
        self.countLabel.text=[NSString stringWithFormat:@"(%lu/%@)",(unsigned long)_textView.text.length, @(self.maxTextCount)];
        [self changeTextWithTextColor:[UIColor orangeColor] OfLabel:self.countLabel withLocation:1 andLength:self.countLabel.text.length-5];
    }
    
    if ([_delegate respondsToSelector:@selector(textViewDidChange:)]) {
        [_delegate textViewDidChange:textView];
    }
}

• 這里進(jìn)行了一個(gè)高亮判斷和輸入法的判斷，主要是在計(jì)數(shù)的時(shí)候，能夠在選中高亮文字之后再執(zhí)行，這樣就不會(huì)造成輸入字?jǐn)?shù)達(dá)到最大限制時(shí)計(jì)數(shù)label顯示不正確，或者是鍵盤(pán)直接不能用了,達(dá)到的效果就是字?jǐn)?shù)達(dá)到限制時(shí)，鍵盤(pán)還能輸入，textView不再輸入或高亮選中無(wú)效

3.在需要的地方調(diào)用就可以了

 //textView
    LALCustomTextView *customTextView =[[NSBundle mainBundle] loadNibNamed:@"LALCustomTextView" owner:self options:nil].lastObject;
    
    [self.view addSubview:customTextView];
    customTextView.delegate = self;
    customTextView.clearButtonType = ClearButtonAppearWhenEditing;
    [customTextView setPlaceholder:@"編輯新通知,60字以內(nèi)..." contentText:_inputText maxTextCount:60];
    __weak typeof (self) weakSelf = self;
    customTextView.frame = CGRectMake(weakSelf.view.frame.origin.x, 0, weakSelf.view.frame.size.width, 200);

具體代碼可直接去下載，有錯(cuò)誤或改進(jìn)的地方，請(qǐng)直接@我，不吝賜教。
代碼傳送門(mén)：demo