- 因为在项目中有需要多行输入，并且带占位符的输入文本，UITextField并不能满足的我们的需求，所以下面自定义了一个带占位符的TextView.
LTTextView *textView = [[ LTTextView alloc]initWithFrame:CGRectMake(LTMargin, LTMarginBig, ScreenWidth - 2*LTMargin , 200)];
textView.placeholderTextView.text = @"这个是占位符，请输入....";
[self.view addSubview:textView];
LTTextView *textView1 = [LTTextView placeholderTextView];
textView1.frame = CGRectMake(LTMargin, 240, ScreenWidth - 2*LTMargin , 200);
textView1.placeholderTextView.text = @"这个是测试的，请输入....";
[self.view addSubview:textView1];
//
// LTTextView.h
// LTTextvViewDemo
//
// Created by WJX on 16/7/8.
// Copyright © 2016年 wjx. All rights reserved.
//
#import <UIKit/UIKit.h>
@interface LTTextView : UIView
/** */
@property (nonatomic, strong, nullable) UITextView *textView;
/** 占位*/
@property (nonatomic, strong, nullable) UITextView *placeholderTextView;
+ (instancetype )placeholderTextView;
@end
//
// LTTextView.m
// LTTextvViewDemo
//
// Created by WJX on 16/7/8.
// Copyright © 2016年 wjx. All rights reserved.
//
#import "LTTextView.h"
//这里是限制字数
#define MAX_WORD_LIMIT 200
@interface LTTextView ()<UITextViewDelegate,UITextFieldDelegate>
@end
@implementation LTTextView
#pragma mark - --- init 视图初始化 ---
+ (instancetype )placeholderTextView{
// init方法内部会自动调用initWithFrame:方法
return [[self alloc]init];
}
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self setupUI];
}
return self;
}
- (void)setupUI{
[self addSubview:self.placeholderTextView];
[self addSubview:self.textView];
}
#pragma mark - --- delegate 视图委托 ---
/**
* 这个方法专门用来布局子控件，一般在这里设置子控件的frame
* 当控件本身的尺寸发生改变的时候，系统会自动调用这个方法
*
*/
- (void)layoutSubviews{
[super layoutSubviews];
CGFloat textViewW = self.frame.size.width;
CGFloat textViewH = self.frame.size.height;
self.textView.frame = CGRectMake(0, 0, textViewW, textViewH );
self.placeholderTextView.frame = CGRectMake(0, 0, textViewW, textViewH );
}
//点击return 按钮 去掉
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
return YES;
}
-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
if (text.length == 0 && range.location == 0) {
self.placeholderTextView.hidden = NO;
}else{
self.placeholderTextView.hidden =YES;
}
if ([text isEqualToString:@"\n"]) {
[textView resignFirstResponder];
return NO;
}
return YES;
}
/*由于联想输入的时候，函数textView:shouldChangeTextInRange:replacementText:无法判断字数，
因此使用textViewDidChange对TextView里面的字数进行判断
*/
- (void)textViewDidChange:(UITextView *)textView
{
if (textView.text.length == 0) {
self.placeholderTextView.hidden = NO;
}else{
self.placeholderTextView.hidden =YES;
}
//该判断用于联想输入
if (textView.text.length > MAX_WORD_LIMIT)
{
textView.text = [textView.text substringToIndex:MAX_WORD_LIMIT];
}
}
#pragma mark - --- event response 事件相应 ---
#pragma mark - --- private methods 私有方法 ---
#pragma mark - --- setters 属性 ---
#pragma mark - --- getters 属性 —--
- (UITextView *)textView{
if (!_textView) {
_textView = [[UITextView alloc]init];
_textView.backgroundColor = [UIColor clearColor];
_textView.layer.borderColor = [UIColor lightGrayColor].CGColor;
_textView.layer.borderWidth = 0.5;
_textView.font = [UIFont systemFontOfSize:13];
_textView.delegate = self;
}
return _textView;
}
- (UITextView *)placeholderTextView{
if (!_placeholderTextView) {
_placeholderTextView = [[UITextView alloc]init];
_placeholderTextView.font = [UIFont systemFontOfSize:13];
_placeholderTextView.textColor = [UIColor colorWithRed:133/255 green:136/255 blue:140/255 alpha:0.2];
}
return _placeholderTextView;
}
@end
