1.在用UITextView的时候一直很苦恼placeholder的设置，最开始是通过添加label，后来觉得麻烦，就通过UITextView本身的一些特性来进行模拟。
2.UITextView的行间距设置方法网上很容易搜的到，但是运用中却发现直接设置根本不行，原因是textView一开始必需要有内容（个中原因，不深究，估计是系统级的），但是有又很奇怪，所以想到个主意，一开始就给textView内容，输入时删除，这样就有了1中的placeholder效果，可谓一举两得。
3.做出了placeholder的效果，颜色也需要区别，发现这句：
_textView.textColor = [UIColor redColor];
完全没有作用，所以也需要通过属性来设置了，具体的要实现以上内容的代码请看下面
首先要支持UITextViewDelegate；
接着看代码：
#import "ViewController.h" @interface ViewController ()<UITextViewDelegate> { UITextView *_textView; } @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. self.automaticallyAdjustsScrollViewInsets = NO; _textView = [[UITextView alloc]initWithFrame:CGRectMake(10, 100, 300, 80)]; _textView.delegate = self; _textView.text = @"请在这里输入内容"; _textView.layer.cornerRadius = 10; _textView.layer.borderWidth = 1; _textView.layer.borderColor = [UIColor blackColor].CGColor; [self.view addSubview:_textView]; //有内容时该设置才生效，需要切记 NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc]init]; paragraphStyle.lineSpacing = 8; NSDictionary *attributes = @{NSFontAttributeName:[UIFont systemFontOfSize:15],NSParagraphStyleAttributeName:paragraphStyle,NSForegroundColorAttributeName:[UIColor grayColor]}; _textView.attributedText = [[NSAttributedString alloc]initWithString:_textView.text attributes:attributes]; } - (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event { //收起键盘 [_textView resignFirstResponder]; } #pragma mark - UITextViewDelegate - (BOOL)textViewShouldBeginEditing:(UITextView *)textView { //编辑时删除代替placeholder效果的内容 if ([_textView.text isEqualToString:@"请在这里输入内容"]) { textView.text = @""; NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc]init]; paragraphStyle.lineSpacing = 8; NSDictionary *attributes = @{NSFontAttributeName:[UIFont systemFontOfSize:15],NSParagraphStyleAttributeName:paragraphStyle,NSForegroundColorAttributeName:[UIColor blackColor]}; _textView.attributedText = [[NSAttributedString alloc]initWithString:_textView.text attributes:attributes]; } return YES; } - (void)textViewDidChange:(UITextView *)textView { //编辑时把placeholder效果颜色变为正常效果 NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc]init]; paragraphStyle.lineSpacing = 8; NSDictionary *attributes = @{NSFontAttributeName:[UIFont systemFontOfSize:15],NSParagraphStyleAttributeName:paragraphStyle,NSForegroundColorAttributeName:[UIColor blackColor]}; _textView.attributedText = [[NSAttributedString alloc]initWithString:_textView.text attributes:attributes]; } - (void)textViewDidEndEditing:(UITextView *)textView { //若编辑结束，内容为空，变最开始placeholder效果 if ([textView.text isEqualToString:@""]) { _textView.text = @"请在这里输入内容"; NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc]init]; paragraphStyle.lineSpacing = 8; NSDictionary *attributes = @{NSFontAttributeName:[UIFont systemFontOfSize:15],NSParagraphStyleAttributeName:paragraphStyle,NSForegroundColorAttributeName:[UIColor grayColor]}; _textView.attributedText = [[NSAttributedString alloc]initWithString:_textView.text attributes:attributes]; } } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } @end
比较容易看懂，就不多解释了。
