iOS开发获取掉线的蓝牙设备

前不久，同学问了我如何快速的获取到那个设备掉线了。就写了个demo。如下

//

//  ViewController.m

//  蓝牙demo

//

//  Created by mlh on 16/10/24.

//  Copyright © 2016年 mlh. All rights reserved.

//

#import "ViewController.h"

#import "Model.h"

@interface ViewController ()

{

NSArray *dataArr1;//上一次的设备数组

NSArray *dataArr2;//最新一次的设备数组

}

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

// Do any additional setup after loading the view, typically from a nib.

//初始化设备数组

dataArr1=@[];

dataArr2=[NSArray array];

NSMutableArray *tempArr=[NSMutableArray array];

for (int i=0; i<5 ;i++) {

Model *model=[[Model alloc]init];

model.ID=[NSString stringWithFormat:@"%zd",i];

[tempArr addObject:model];

}

dataArr2=tempArr;

[self scanDevice];

}

#pragma mark - 模拟扫描设备

-(void)scanDevice{

dataArr1=dataArr2;

[dataArr1 enumerateObjectsUsingBlock:^(Model * obj, NSUInteger idx, BOOL * _Nonnull stop) {

NSLog(@"dataArr2==%@",obj.ID);

}];

NSMutableArray *tempArr=[NSMutableArray array];

for (int i=0; i<5 ;i+=2) {

Model *model=[[Model alloc]init];

model.ID=[NSString stringWithFormat:@"%zd",i];

[tempArr addObject:model];

}

dataArr2=tempArr;

[dataArr2 enumerateObjectsUsingBlock:^(Model * obj, NSUInteger idx, BOOL * _Nonnull stop) {

NSLog(@"dataArr2==%@",obj.ID);

}];

[self log];

}

-(void)log{

#pragma mark - 两个数组比较，看看那个设备掉线了

//SELF.ID 就是说是model里面的属性

NSPredicate * filterPredicate = [NSPredicate predicateWithFormat:@"NOT(SELF.ID IN %@)",[dataArr2 valueForKey:@"ID"] ];

//过滤数组

NSArray * reslutFilteredArray = [dataArr1 filteredArrayUsingPredicate:filterPredicate];

NSLog(@"Reslut Filtered Array = %@",reslutFilteredArray);

[reslutFilteredArray enumerateObjectsUsingBlock:^(Model * obj, NSUInteger idx, BOOL * _Nonnull stop) {

NSLog(@"%@,掉线了",obj.ID);

}];

}

- (void)didReceiveMemoryWarning {

[super didReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@end