RoundedCornersTextView.h

//
//  RoundedCornersTextView.h
//
//  Created by Maxim Keegan on 03.06.15.
//  Copyright (c) 2015 Keegan. All rights reserved.
//

#import <UIKit/UIKit.h>

IB_DESIGNABLE
@interface RoundedCornersTextView : UITextView

@property (nonatomic) IBInspectable UIColor *borderColor;
@property (nonatomic) IBInspectable CGFloat borderWidth;
@property (nonatomic) IBInspectable CGFloat cornerRadius;
@property (nonatomic, retain) IBInspectable NSString *placeholder;
@property (nonatomic, retain) IBInspectable UIColor *placeholderColor;



@end

RoundedCornersTextView.m

//
//  RoundedCornersTextView.m
//
//  Created by Maxim Keegan on 03.06.15.
//  Copyright (c) 2015 Keegan. All rights reserved.
//

#import "RoundedCornersTextView.h"

@interface RoundedCornersTextView ()

@property (nonatomic, retain) UILabel *placeHolderLabel;


@end

@implementation RoundedCornersTextView

- (void) setCornerRadius:(CGFloat)cornerRadius {
    _cornerRadius = cornerRadius;
    if (cornerRadius > 0) {
        [self setClipsToBounds:YES];
    }
    self.layer.cornerRadius = _cornerRadius;
}

- (void) setBorderColor:(UIColor *)borderColor {
    _borderColor = borderColor;
    self.layer.borderColor = _borderColor.CGColor;
}

- (void) setBorderWidth:(CGFloat)borderWidth {
    _borderWidth = borderWidth;
    self.layer.borderWidth = _borderWidth;
}



CGFloat const UI_PLACEHOLDER_TEXT_CHANGED_ANIMATION_DURATION = 0.25;

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
#if __has_feature(objc_arc)
#else
    [_placeHolderLabel release]; _placeHolderLabel = nil;
    [_placeholderColor release]; _placeholderColor = nil;
    [_placeholder release]; _placeholder = nil;
    [super dealloc];
#endif
}

- (void)awakeFromNib
{
    [super awakeFromNib];
    
    // Use Interface Builder User Defined Runtime Attributes to set
    // placeholder and placeholderColor in Interface Builder.
    if (!self.placeholder) {
        [self setPlaceholder:@""];
    }
    
    if (!self.placeholderColor) {
        [self setPlaceholderColor:[UIColor lightGrayColor]];
    }
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textChanged:) name:UITextViewTextDidChangeNotification object:nil];
}

- (id)initWithFrame:(CGRect)frame
{
    if( (self = [super initWithFrame:frame]) )
    {
        [self setPlaceholder:@""];
        [self setPlaceholderColor:[UIColor lightGrayColor]];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textChanged:) name:UITextViewTextDidChangeNotification object:nil];
    }
    return self;
}

- (void)textChanged:(NSNotification *)notification
{
    if([[self placeholder] length] == 0)
    {
        return;
    }
    
    [UIView animateWithDuration:UI_PLACEHOLDER_TEXT_CHANGED_ANIMATION_DURATION animations:^{
        if([[self text] length] == 0)
        {
            [[self viewWithTag:999] setAlpha:1];
        }
        else
        {
            [[self viewWithTag:999] setAlpha:0];
        }
    }];
}

- (void)setText:(NSString *)text {
    [super setText:text];
    [self textChanged:nil];
}

- (void)drawRect:(CGRect)rect
{
    if( [[self placeholder] length] > 0 )
    {
        if (_placeHolderLabel == nil )
        {
            _placeHolderLabel = [[UILabel alloc] initWithFrame:CGRectMake(8,8,self.bounds.size.width - 16,0)];
            _placeHolderLabel.lineBreakMode = NSLineBreakByWordWrapping;
            _placeHolderLabel.numberOfLines = 0;
            _placeHolderLabel.font = self.font;
            _placeHolderLabel.backgroundColor = [UIColor clearColor];
            _placeHolderLabel.textColor = self.placeholderColor;
            _placeHolderLabel.alpha = 0;
            _placeHolderLabel.tag = 999;
            [self addSubview:_placeHolderLabel];
        }
        
        _placeHolderLabel.text = self.placeholder;
        [_placeHolderLabel sizeToFit];
        [self sendSubviewToBack:_placeHolderLabel];
    }
    
    if( [[self text] length] == 0 && [[self placeholder] length] > 0 )
    {
        [[self viewWithTag:999] setAlpha:1];
    }
    
    [super drawRect:rect];
}

@end