iOS设计模式 - 中介者
原理图
说明
用一个中介对象来封装一系列的对象交互。中介者使各对象不需要显式地相互引用，从而使其耦合松散，而且可以独立地改变它们之间的交互。
注：中介者对象本身没有复用价值，只是将逻辑操作封装在一个类里面而已
源码
https://github.com/YouXianMing/iOS-Design-Patterns
//
// TextFieldMediator.h
// MediatorPattern
//
// Created by YouXianMing on 15/10/26.
// Copyright © 2015年 ZiPeiYi. All rights reserved.
// #import <Foundation/Foundation.h>
#import <UIKit/UIKit.h> @interface TextFieldMediator : NSObject <UITextFieldDelegate> @property (nonatomic, weak) UITextField *textField_1;
@property (nonatomic, weak) UITextField *textField_2;
@property (nonatomic, weak) UITextField *textField_3; @end
//
// TextFieldMediator.m
// MediatorPattern
//
// Created by YouXianMing on 15/10/26.
// Copyright © 2015年 ZiPeiYi. All rights reserved.
// #import "TextFieldMediator.h" @implementation TextFieldMediator - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string { if ([textField isEqual:self.textField_1]) { NSString *currentNum = [self currentStringWithTextField:textField replacementString:string inRange:range];
self.textField_2.text = [NSString stringWithFormat:@"%.f", currentNum.floatValue * ];
self.textField_3.text = [NSString stringWithFormat:@"%.f", currentNum.floatValue * ]; } else if ([textField isEqual:self.textField_2]) { NSString *currentNum = [self currentStringWithTextField:textField replacementString:string inRange:range];
self.textField_1.text = [NSString stringWithFormat:@"%.f", currentNum.floatValue / ];
self.textField_3.text = [NSString stringWithFormat:@"%.f", currentNum.floatValue * ]; } else { NSString *currentNum = [self currentStringWithTextField:textField replacementString:string inRange:range];
self.textField_1.text = [NSString stringWithFormat:@"%.f", currentNum.floatValue / ];
self.textField_2.text = [NSString stringWithFormat:@"%.f", currentNum.floatValue / ];
} return YES;
} - (NSString *)currentStringWithTextField:(UITextField *)textField replacementString:(NSString *)string inRange:(NSRange)range { NSMutableString *mutableString = [NSMutableString stringWithString:textField.text]; if (string.length) { [mutableString insertString:string atIndex:range.location]; } else { [mutableString deleteCharactersInRange:range];
} return [NSString stringWithString:mutableString];
} @end
//
// ViewController.m
// MediatorPattern
//
// Created by YouXianMing on 15/10/26.
// Copyright © 2015年 ZiPeiYi. All rights reserved.
// #import "ViewController.h"
#import "TextFieldMediator.h" @interface ViewController () <UITextFieldDelegate> @property (nonatomic, strong) UITextField *textField_1;
@property (nonatomic, strong) UITextField *textField_2;
@property (nonatomic, strong) UITextField *textField_3; @property (nonatomic, strong) TextFieldMediator *mediator; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // 初始化控件
self.textField_1 = [self createTextFieldWithFrame:CGRectMake(, + * , , )];
self.textField_2 = [self createTextFieldWithFrame:CGRectMake(, + * , , )];
self.textField_3 = [self createTextFieldWithFrame:CGRectMake(, + * , , )];
[self.view addSubview:self.textField_1];
[self.view addSubview:self.textField_2];
[self.view addSubview:self.textField_3]; // 初始化中介者
self.mediator = [[TextFieldMediator alloc] init];
self.mediator.textField_1 = self.textField_1;
self.mediator.textField_2 = self.textField_2;
self.mediator.textField_3 = self.textField_3; // 将代理设置成中介者
self.textField_1.delegate = self.mediator;
self.textField_2.delegate = self.mediator;
self.textField_3.delegate = self.mediator;
} - (UITextField *)createTextFieldWithFrame:(CGRect)frame { UITextField *tmpField = [[UITextField alloc] initWithFrame:frame];
tmpField.layer.borderWidth = 0.5f;
tmpField.keyboardType = UIKeyboardTypeNumberPad; return tmpField;
} @end
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