iosiOStextView实现文字高度自适应

Posted 2020-08-23 孙富有(iOS工程师)

跟为textView设置提示性文字一样   需要在textView的代理方法中实现如下

如有偏差  请谅解

定义UITextView，实现UITextViewDelegate:

-(UITextView *)textView{

    if (!_textView) {

        //http://www.cnblogs.com/xiaofeixiang/

        _textView=[[UITextView alloc]initWithFrame:CGRectMake(30, 200, CGRectGetWidth([[UIScreen mainScreen] bounds])-60, 30)];

        [_textView setTextColor:[UIColor redColor]];

        [_textView.layer setBorderColor:[[UIColor blackColor] CGColor]];

        [_textView setFont:[UIFont systemFontOfSize:15]];

        [_textView.layer setBorderWidth:1.0f];

        [_textView setDelegate:self];

    }

    return _textView;

}

 

-(void)textViewDidChange:(UITextView *)textView{

    //博客园-FlyElephant

    static CGFloat maxHeight =60.0f;

    CGRect frame = textView.frame;

    CGSize constraintSize = CGSizeMake(frame.size.width, MAXFLOAT);

    CGSize size = [textView sizeThatFits:constraintSize];

    if (size.height<=frame.size.height) {

        size.height=frame.size.height;

    }else{

        if (size.height >= maxHeight)

        {

            size.height = maxHeight;

            textView.scrollEnabled = YES;   // 允许滚动

        }

        else

        {

            textView.scrollEnabled = NO;    // 不允许滚动

        }

    }

    textView.frame = CGRectMake(frame.origin.x, frame.origin.y, frame.size.width, size.height);

}