UITextView的placeholder属性

写项目的时候，发现UITextField并没有换行的属性，所以采用UITextView来实现，最后发现一个问题，UITextView并没有placeholder(占位符)属性。

解决方案：直接看代码如下：

#import "DiscussViewController.h"

#import "ProgressHUD.h"

#import "TitleViewController.h"

@interface DiscussViewController ()<UITextViewDelegate>

@property (nonatomic, strong) UITextView *discussView;

@property (nonatomic, strong) UILabel *lable;

@property (nonatomic, strong) UIButton *sendBtn;//发送按钮

@end

@implementation DiscussViewController

- (void)viewDidLoad {

[super viewDidLoad];

// Do any additional setup after loading the view.

self.title = @"评论";

[self showBarButtonWithImage:@"back_arrow"];

self.view.backgroundColor = [UIColor colorWithRed:232/255.0 green:233/255.0 blue:232/255.0 alpha:1.0];

[self.view addSubview:self.discussView];

[self.view addSubview:self.lable];

self.sendBtn = [UIButton buttonWithType:UIButtonTypeCustom];

self.sendBtn.frame = CGRectMake(0, 0, 60, 44);

[self.sendBtn setTitle:@"发送" forState:UIControlStateNormal];

//调整btn标题所在的位置，距离btn顶部，左边，底部，右边的距离

[self.sendBtn setTitleEdgeInsets:UIEdgeInsetsMake(0, 0, 0, 0)];

[self.sendBtn addTarget:self action:@selector(sendBtnAction) forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *rightBarBtn = [[UIBarButtonItem alloc] initWithCustomView:self.sendBtn];

rightBarBtn.tintColor = [UIColor whiteColor];

self.navigationItem.rightBarButtonItem = rightBarBtn;

}

#pragma mark ------------- lazy Loading

- (UITextView *)discussView{

if (_discussView == nil) {

self.discussView = [[UITextView alloc] initWithFrame:CGRectMake(20, KScreenWidth/10, KScreenWidth-40, KScreenWidth/2)];

self.discussView.backgroundColor = [UIColor whiteColor];

self.discussView.hidden = NO;

self.discussView.delegate = self;

// self.discussView.text = @"_说点什么吧";

self.discussView.textColor = [UIColor lightGrayColor];

self.discussView.font = [UIFont systemFontOfSize:15.0f];

}

return _discussView;

}

- (UILabel *)lable{

if (_lable == nil) {

self.lable = [[UILabel alloc] initWithFrame:CGRectMake(20, KScreenWidth/10, KScreenWidth-40, KScreenWidth/2)];

self.lable.text = @"_说点什么吧~";

self.lable.enabled = NO;

self.lable.numberOfLines = 0;

self.lable.backgroundColor = [UIColor clearColor];

}

return _lable;

}

//实现UITextView的代理

-(void)textViewDidChange:(UITextView *)textView

{

self.discussView.text = textView.text;

if (textView.text.length == 0) {

self.lable.text = @"_说点什么吧";

}else{

self.lable.text = @"";

}

}

#pragma mark --------- 发送按钮的点击方法

- (void)sendBtnAction{

if (self.discussView.text.length <= 0) {

[ProgressHUD showError:@"评论内容不能为空呦"];

}else{

[ProgressHUD showSuccess:@"发送成功"];

[self.navigationController popToRootViewControllerAnimated:YES];

}

}

//点击空白处回收键盘

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

[self.discussView resignFirstResponder];

}