iOS-意见反馈UITextView的使用+不能输入字符输入

@interface DMFeedbackViewController ()<UITextViewDelegate,UIAlertViewDelegate>
@property (nonatomic, strong) UITextView *feedbackTextView;//意见反馈输入框
@property (nonatomic, strong) UILabel *mostLabel;//最多还可以输入
@property (nonatomic, strong) UIButton *submitBt;//提交
@property (nonatomic, strong) UILabel *feedbackNoteLabel;//在此输入反馈意见
@end

判断用户是否输入文字，feedbackNoteLabel文字显示或者隐藏

利用通知解决：

[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(textViewChange) name:UITextViewTextDidChangeNotification object:nil];

//释放通知

-(void)dealloc
{
    
    //    debugMethod();
    [[NSNotificationCenter defaultCenter]removeObserver:self name:UITextViewTextDidChangeNotification object:nil];
    
    }

-(void)textViewChange
{
    
    if (_feedbackTextView.text.length== 0) {
        [_feedbackNoteLabel setHidden:NO];
        
        
    }else
    {
        [_feedbackNoteLabel setHidden:YES];
        
    }
    
}
由于设计需要，uitextview的输入框特别长，提交按钮在最底部，为了方便用户体验，添加了拖拽也就是滑动手势

UIPanGestureRecognizer  *panGestureRecognizer= [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanGestures:)];
    panGestureRecognizer.minimumNumberOfTouches = 1;
    panGestureRecognizer.maximumNumberOfTouches = 5;
    [self.view addGestureRecognizer:panGestureRecognizer];

#pragma mark --滑动空白区域收起键盘
-(void)handlePanGestures:(UIPanGestureRecognizer *)sender{

[self.view endEditing:YES];

}

####您最多还可以输入多个字的代理方法

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
    NSString *temp = [textView.text stringByReplacingCharactersInRange:range withString:text];
    
    if (temp.length== 0) {
      //输入文字为0，提交按钮触摸事件隐藏
       [_submitBt setBackgroundColor:DMRGB(235, 235, 240)];
        [_submitBt setTitleColor:DMRGB(210, 210, 210) forState:UIControlStateNormal];
        _submitBt.userInteractionEnabled = NO;
        
    }
   else
    {

[_submitBt setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
        _submitBt.backgroundColor = [UIColor colorWithRed:65.0/255 green:109.0/255 blue:218.0/255 alpha:1];
        _submitBt.userInteractionEnabled = YES;
    }
  
    NSString *str = [NSString stringWithFormat:@"%lu",100-temp.length];
    _mostLabel.attributedText =[self getString:[NSString stringWithFormat:@"您最多还可以输入%lu个字",100-temp.length] WithFontSize:DMFontSize14 WithTextColer:DMRGB(153, 153, 153) otherTextColer:DMRGB(237, 95, 95) WithRange:NSMakeRange(8,str.length)];

if (temp.length >= 100) {  //如果输入超过规定的字数100，就不再让输入
        return NO;
    }
    return YES;

}

-(NSMutableAttributedString*)getString:(NSString*)str  WithFontSize:(CGFloat)fontSize WithTextColer:(UIColor *)color  otherTextColer:(UIColor *)othercolor WithRange:(NSRange)strRange
{
    NSMutableAttributedString *attriString = [[NSMutableAttributedString alloc] initWithString:str];
    NSRange mainRange=NSMakeRange(0, str.length);
    [attriString setAttributes:  @{NSFontAttributeName: [UIFont systemFontOfSize:fontSize],
                                   NSForegroundColorAttributeName: color} range:mainRange];
    [attriString setAttributes:  @{NSFontAttributeName: [UIFont systemFontOfSize:fontSize],
                                   NSForegroundColorAttributeName: othercolor} range:strRange];
    return attriString;
    
}

本来以为解决了，结果测试发现了一个问题：当输入拼音的时候，那个提示语100并没有被减去。

百度了资料说：

这样在输入全部是英文的情况下是可以的. 但是当输入是中文时, 由于shouldChangeCharactersInRange判断的是当前键盘的字符数,最终采用了通知方法解决。

方法如下：

把那个shouldChangeCharactersInRange方法注释掉。代码如下：

- (void)initParameters
{
    [super initParameters];
    
    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(textViewChange) name:UITextViewTextDidChangeNotification object:nil];
    
    //关于输入拼音和英文状态下如何正确的统计输入的文字字数
 
    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(textViewEditChange:) name:UITextViewTextDidChangeNotification object:_feedbackTextView];
}

-(void)dealloc
{
    
    //    debugMethod();
    [[NSNotificationCenter defaultCenter]removeObserver:self name:UITextViewTextDidChangeNotification object:nil];
     [[NSNotificationCenter defaultCenter]removeObserver:self name:UITextViewTextDidChangeNotification object:_feedbackTextView];
    
}

#pragma mark 通知 方法

-(void)textViewChange
{
   
    
    if (_feedbackTextView.text.length== 0) {
        [_feedbackNoteLabel setHidden:NO];
 
    }else
    {
        [_feedbackNoteLabel setHidden:YES];
       
}
    
}

//关于输入拼音和英文状态下如何正确的统计输入的文字字数
-(void)textViewEditChange:(NSNotification *)obj{
 
    UITextView *textView = (UITextView *)obj.object;
    NSString *temp = textView.text;
    
    if (temp.length== 0) {
        
        [_submitBt setBackgroundColor:DMRGB(235, 235, 240)];
        [_submitBt setTitleColor:DMRGB(210, 210, 210) forState:UIControlStateNormal];
        _submitBt.userInteractionEnabled = NO;
        
    }
    else
    {
        [_submitBt setTitleColor:DMRGB(255, 255, 255) forState:UIControlStateNormal];
        _submitBt.backgroundColor = [UIColor colorWithRed:240.0/255 green:77.0/255 blue:77.0/255 alpha:1];
        _submitBt.userInteractionEnabled = YES;
    }
    
    NSString *lang = [[UITextInputMode currentInputMode] primaryLanguage]; // 键盘输入模式
    if ([lang isEqualToString:@"zh-hans"]) { // 简体中文输入，包括简体拼音，健体五笔，简体手写
        
        NSString *str = [NSString stringWithFormat:@"%lu",100-temp.length];
        _mostLabel.attributedText =[self getString:[NSString stringWithFormat:@"您最多还可以输入%lu个字",100-temp.length] WithFontSize:DMFontSize14 WithTextColer:DMSecondaryTextColor otherTextColer:DMRGB(237, 95, 95) WithRange:NSMakeRange(8,str.length)];
        
        UITextRange *selectedRange = [textView markedTextRange];
        //获取高亮部分
        UITextPosition *position = [textView positionFromPosition:selectedRange.start offset:0];
        
        if (!position) {  //如果没有高亮选择的字，则对已经输入的文字进行字数统计和限制
            if (temp.length>100) {
                
              
               textView.text = [temp substringToIndex:100];
            }
        }
        else{  //有高亮选择的字，不对文字进行字数统计和限制
        
        }
     
}
    else{// 中文输入法以外的直接对其统计限制即可，不考虑其他语种情况
        
        NSString *str = [NSString stringWithFormat:@"%lu",100-temp.length];
        _mostLabel.attributedText =[self getString:[NSString stringWithFormat:@"您最多还可以输入%lu个字",100-temp.length] WithFontSize:DMFontSize14 WithTextColer:DMSecondaryTextColor otherTextColer:DMRGB(237, 95, 95) WithRange:NSMakeRange(8,str.length)];
    
   
        if (temp.length>100) {  //超过最大字符100，不让键盘输入
            
            textView.text = [temp substringToIndex:100];
        }
    }
   
}就可以了。

最后一步：关于emoji表情不能被输入，怎么解决？

如下：

#pragma mark - 代理   //用户完成编辑后所提示的事
-(void)textViewDidEndEditing:(UITextView *)textView{
        if ([self stringContainsEmoji:self.feedbackTextView.text]) {
            UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"不能带有表情符号，请输入中文" message:nil delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
            [alertView show];
        }
}
#pragma mark 判断NSString字符串是否包含emoji表情
- (BOOL)stringContainsEmoji:(NSString *)string{

__block BOOL returnValue = NO;
    
    [string enumerateSubstringsInRange:NSMakeRange(0, [string length])
                               options:NSStringEnumerationByComposedCharacterSequences
                            usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
                                const unichar hs = [substring characterAtIndex:0];
                                if (0xd800 <= hs && hs <= 0xdbff) {
                                    if (substring.length > 1) {
                                        const unichar ls = [substring characterAtIndex:1];
                                        const int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;
                                        if (0x1d000 <= uc && uc <= 0x1f77f) {
                                            returnValue = YES;
                                        }
                                    }
                                } else if (substring.length > 1) {
                                    const unichar ls = [substring characterAtIndex:1];
                                    if (ls == 0x20e3) {
                                        returnValue = YES;
                                    }
                                } else {
                                    if (0x2100 <= hs && hs <= 0x27ff) {
                                        returnValue = YES;
                                    } else if (0x2B05 <= hs && hs <= 0x2b07) {
                                        returnValue = YES;
                                    } else if (0x2934 <= hs && hs <= 0x2935) {
                                        returnValue = YES;
                                    } else if (0x3297 <= hs && hs <= 0x3299) {
                                        returnValue = YES;
                                    } else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50) {
                                        returnValue = YES;
                                    }
                                }
                            }];
    
    return returnValue;

}