日常更新知识点

1、添加系统提示音和震动
2、在xib 中使用 UIScrollView，但是问题是.m文件中设置contentsize 无效
3、将数组中的内容分拼接成字符串
4、判断字典是否包含特定Key值
5、过滤emoji表情键盘输入，包含输入哈哈引出的微笑表情
6、dismissViewController到根视图
7、pop返回到指定控制器
8、数据处理 (比较两个数组，并除去相同元素)

1、添加系统提示音和震动

• 工程下添加AudioToolbox.framework
• 添加头文件#import <AudioToolbox/AudioToolbox.h>
• appDelegate的代理方法didReceiveRemoteNotification中添加
  AudioServicesPlaySystemSound(1007);//系统提示音 AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);//震动

2、在xib 中使用 UIScrollView，但是问题是.m文件中设置contentsize 无效

• 问题分析
  xib 中勾选了autolayout选项，在autolayout下，iOS计算UIScrollView的contentsize的机制是略有不同。在autolayout中，会在viewDidAppear之前根据subview的constraint重新计算UIScrollView的contentsize。 当在viewdidload里手动设置contentsize时，会再重新计算一次，把前面手动设置的值覆盖掉。
• 解决方法
  1 去除autolayout选项，自己手动设置contentsize
  2 如果要使用autolayout，则需要设置subview的constraint，让系统自动根据constraint计算出contentsize
  3 在viewDidAppear里面自己手动设置contentsize

3、将数组中的内容分拼接成字符串

NSString *string = [array componentsJoinedByString:@","];//用,分割

打印array：(
    1,
    2,
)
打印string：1,2

4、判断字典是否包含特定Key值

if([[dict allKeys] containsObject:@"key"]){
   //有
}else{
   //没有
}

5、过滤emoji表情键盘输入，包含输入哈哈引出的微笑表情

当选择表情键盘输入时return NO

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
   // 不让输入表情
   if ([textView isFirstResponder]) {
       //表情键盘
       if ([[[textView textInputMode] primaryLanguage] isEqualToString:@"emoji"] || ![[textView textInputMode] primaryLanguage]) {
           return NO;
       }else{//
           return ![self stringContainsEmoji:text];
       }
       
   }
   
   return YES;
}
// 过滤所有表情  https://gist.github.com/cihancimen/4146056
- (BOOL)stringContainsEmoji:(NSString *)string {
   __block BOOL returnValue = NO;
   [string enumerateSubstringsInRange:NSMakeRange(0, [string length]) options:NSStringEnumerationByComposedCharacterSequences usingBlock:
    ^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
        
        const unichar hs = [substring characterAtIndex:0];
        // surrogate pair
        if (0xd800 <= hs && hs <= 0xdbff) {
            if (substring.length > 1) {
                const unichar ls = [substring characterAtIndex:1];
                const int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;
                if (0x1d000 <= uc && uc <= 0x1f77f) {
                    returnValue = YES;
                }
            }
        } else if (substring.length > 1) {
            const unichar ls = [substring characterAtIndex:1];
            if (ls == 0x20e3) {
                returnValue = YES;
            }
            
        } else {
            // non surrogate
//             if (0x2100 <= hs && hs <= 0x27ff) {
//                 returnValue = YES;
//             }
            if (0x2B05 <= hs && hs <= 0x2b07) {
                returnValue = YES;
            } else if (0x2934 <= hs && hs <= 0x2935) {
                returnValue = YES;
            } else if (0x3297 <= hs && hs <= 0x3299) {
                returnValue = YES;
            } else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50) {
                returnValue = YES;
            }
        }
    }];
   
   return returnValue;
}

6、dismissViewController到根视图

如果是在Controller中 则代码如下

 UIViewController *vc =  self;
 while (vc.presentingViewController) {
     vc = vc.presentingViewController;
 }
 [vc dismissViewControllerAnimated:YES completion:nil];  

如果是在视图(View)中 则代码如下

-(void)backClick{  
     UIViewController *vc =  [self viewController];  
     while (vc.presentingViewController) {  
          vc = vc.presentingViewController;  
     }  
     [vc dismissViewControllerAnimated:YES completion:nil];  
 }  

 /** 获取当前view的controller */  
- (UIViewController *)viewController  
{  
    for (UIView *next = [self superview]; next; next = next.superview) {  
         UIResponder *nextResponser = [next nextResponder];  

         if ([nextResponser isKindOfClass:[UIViewController class]]) {  
              return (UIViewController *)nextResponser;  
         }  
    }  
   return nil;  
}  

该代码可返回到根(通过present过来的)Controller

7、pop返回到指定控制器

方法一

 UIViewController *viewCtl = self.navigationController.viewControllers[1];

[self.navigationController popToViewController:viewCtl animated:YES];

方法二

for (UIViewController *controller in self.navigationController.viewControllers) {
          if ([controller isKindOfClass:[SetupViewController class]]) {
                    SetupViewController *revise =(SetupViewController *)controller;
                    [self.navigationController popToViewController:revise animated:YES];
          }
}

8、数据处理 (比较两个数组，并除去相同元素)

    NSArray * arr1 = @[@1,@2,@3];
    NSArray * arr2 = @[@2,@3,@4,@5];
    
    NSPredicate * filterPredicate = [NSPredicate predicateWithFormat:@"NOT (SELF IN %@)",arr1];
    NSArray * filter = [arr2 filteredArrayUsingPredicate:filterPredicate];
    NSLog(@"%@",filter);

打印：

2018-12-20 10:51:59.792762+0800 demo[2898:47742] (
    4,
    5
)