iOS UItextView监听输入特定字符跳转页面选择选项返回

今天有朋友问我一个需求的实现,于是自己写了一个Demo简单的实现了一下:

需求是:

1>比如: 检测用户输入"A"字符串,跳转页面选择选项,将选择的选项放置textView里,作为当前的输入;

2>不是"A"字符,则正常的textView输入;

3.用户跳转选择了,则将选择的输入到textView,否则,还是输入用户输入的字符即可.

实现代码如下:

//
//  ViewController.m
//  Demo
//
//  Created by 思 彭 on 2017/4/30.
//  Copyright © 2017年 思 彭. All rights reserved.
//

#import "ViewController.h"
#import "ViewController1.h"

@interface ViewController ()<UITextViewDelegate>

@property (nonatomic, strong) UITextView *textView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.textView = [[UITextView alloc]initWithFrame:CGRectMake(20, 100, self.view.frame.size.width - 40, 200)];
    self.textView.delegate = self;
    self.textView.backgroundColor = [UIColor lightGrayColor];
    [self.view addSubview:self.textView];
}

- (BOOL)textViewShouldBeginEditing:(UITextView *)textView {
    
    return YES;
}

- (BOOL)textViewShouldEndEditing:(UITextView *)textView {
    
    return YES;
}

- (void)textViewDidBeginEditing:(UITextView *)textView {
    
    
}
- (void)textViewDidEndEditing:(UITextView *)textView {
    
}

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
    
    NSLog(@"%@",text);
    __block BOOL isChangeFlag;
    
    if ([text isEqualToString:@"A"]) {
        // 跳转页面
        ViewController1 *vc1 = [ViewController1 new];
        vc1.block = ^(NSString *str) {
            NSLog(@"str = %@",str);
            NSString *textViewText = textView.text;
            NSString *s = [textViewText substringWithRange:NSMakeRange(0, textViewText.length)];
            if (str.length > 0) {
                isChangeFlag = YES;
                textView.text = [NSString stringWithFormat:@"%@%@",s, str];
            } else {
                isChangeFlag = NO;
                textView.text = [NSString stringWithFormat:@"%@%@",s, text];
            }
        };
        [self.navigationController pushViewController: vc1 animated:YES];
        return isChangeFlag;
    }
    return YES;
}

- (void)textViewDidChange:(UITextView *)textView {
    
}

- (void)textViewDidChangeSelection:(UITextView *)textView {
    
}




@end

跳转页面选择:

//
//  ViewController1.m
//  Demo
//
//  Created by 思 彭 on 2017/4/30.
//  Copyright © 2017年 思 彭. All rights reserved.
//

#import "ViewController1.h"

@interface ViewController1 ()<UITableViewDelegate, UITableViewDataSource>

@property (nonatomic, strong) UITableView *tableView;
@property (nonatomic, copy) NSString *selectedStr;

@end

@implementation ViewController1

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    self.view.backgroundColor = [UIColor whiteColor];
    self.selectedStr = @"";
    [self setUI];
}

#pragma mark - 设置界面

- (void)setUI {
    
    self.tableView = [[UITableView alloc]initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height) style:UITableViewStyleGrouped];
    self.tableView.delegate = self;
    self.tableView.dataSource = self;
    self.tableView.backgroundColor = [UIColor clearColor];
    self.tableView.tableFooterView = [[UIView alloc]init];
    // 注册cell
    [self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:@"cell"];
    [self.view addSubview: self.tableView];
}

#pragma mark - UITableViewDataSource

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    
    return 10;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cell" forIndexPath:indexPath];
    cell.textLabel.text = [NSString stringWithFormat:@"%ld",indexPath.row];
    cell.textLabel.font = [UIFont systemFontOfSize:15];
    return cell;
}

#pragma mark - UITableViewDelegate

- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
    
    return 0.001f;
}

- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section {
    
    return 0.0001f;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    
    NSString *str = [tableView cellForRowAtIndexPath:indexPath].textLabel.text;
    self.selectedStr = str;
    if (self.block) {
        self.block(self.selectedStr);
    }
    [self.navigationController popViewControllerAnimated:YES];
}

@end

总结:

其实主要的实现就在textView的代理的实现: 

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text;