iOS自定義帶有placeholder的TextView（多行）

.h定義：

#import <UIKit/UIKit.h>

@interface CloverText : UITextView <UITextViewDelegate>

@property(nonatomic,strong) UITextView *TV;

- (id)initWithFrame:(CGRect)frame placeholder:(NSString *)placeholder;


@end

.m定義：

#import "CloverText.h"

@implementation CloverText

- (id)initWithFrame:(CGRect)frame placeholder:(NSString *)placeholder
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
        self.TV = [[UITextView alloc]initWithFrame:CGRectMake(0, 0, frame.size.width, frame.size.height)];
        self.TV.text = placeholder;
        self.TV.textColor = [UIColor grayColor];
        self.TV.backgroundColor = [UIColor clearColor];
        self.TV.editable = NO;
        [self addSubview:self.TV];
        [self sendSubviewToBack:self.TV];
        self.delegate = self;
    }
    return self;
}

- (void)textViewDidChange:(UITextView *)textView {
    if (self.text.length == 0) {
        self.TV.hidden = NO;
    }
    else {
        self.TV.hidden = YES;
    }
}

@end

使用方法：

#import "ViewController.h"
#import "CloverText.h"
@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
    self.view.backgroundColor = [UIColor blackColor];
    
    CloverText *text = [[CloverText alloc]initWithFrame:CGRectMake(0, 100, 320, 50) placeholder:@"000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"];
    text.frame = CGRectMake(0, 100, 320, 50);
    text.font = [UIFont systemFontOfSize:13];
    [self.view addSubview:text];
    
}


- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

效果：

DEMO下載地址：http://download.csdn.net/detail/u011918080/6970483