IOS开发基础知识--碎片6

三十三:IOS多视图跳转方法

第一种：

跳转：[selfpresentModalViewController:controlanimated:YES];

返回：[selfdismissModalViewControllerAnimated:YES];

第二种：

跳转：[self.navigationControllerpushViewController:subTableViewControlleranimated:YES];

返回：[self.navigationControllerpopViewControllerAnimated:YES];

第三种:自己控制：[self.viewaddSubview:<#(UIView*)#>][self.viewremoveFromSuperview];

注意:pushViewController和popViewController进行视图间的切换，就必须要求当前视图是个NavigationController,

第四种：
//根据SegueID执行跳转
[selfperformSegueWithIdentifier:@"contactList"sender:nil];

三十四:presentModalViewController与dismissModalViewControllerAnimated注意事项

在实际开发中，如果要弹出视图：

我们常用到presentModalViewController方法和dismissModalViewControllerAnimated方法。

presentModalViewController：弹出视图

dismissModalViewControllerAnimated：隐藏视图

弹出视图：

FeedbackViewController*feedbackViewController=[[FeedbackViewControlleralloc]initWithNibName:@"FeedbackViewController"bundle:nil];

UINavigationController*navigationController=[[UINavigationControlleralloc]initWithRootViewController:feedbackViewController];

[selfpresentModalViewController:navigationControlleranimated:YES];

隐藏视图：

[selfdismissModalViewControllerAnimated:YES];

关于这两个方法的几点说明：

1.iPhone上弹出/隐藏视图时，使用为全屏模式

2.搞清楚谁是presenting，谁是presented

如果A弹出B，那么A为presenting，B为presented。

3.隐藏视图的策略

我们假如A弹出B

就是说，A负责隐藏B；如果我们在B中调用dismissModalViewControllerAnimated方法，那么编译器，自动将消息发送给A。

等等，什么消息？

简单的理解，当执行presentModalViewController:方法：在A弹出B时：

执行A的viewWillDisappear方法，

通知B执行自己的viewWillAppear方法和viewDidAppear
执行A的viewDidDisappear方法

当执行dismissModalViewControllerAnimated方法：隐藏B时：

执行B的viewWillDisappear

通知A执行自己的viewWillAppear方法和viewDidAppear方法

执行B的viewDidDisappear方法

以下我做了个测试来输出一轮AB切换：

A：More

B：Feed

2012-12-2714:01:23.666WTV[1627:11303]-More--viewWillDisappear----

2012-12-2714:01:23.672WTV[1627:11303]-Feed--viewWillAppear----

2012-12-2714:01:24.086WTV[1627:11303]-Feed--viewDidAppear----

2012-12-2714:01:24.087WTV[1627:11303]-More--viewDidDisappear----

2012-12-2714:01:25.745WTV[1627:11303]-Feed--viewWillDisappear----

2012-12-2714:01:25.745WTV[1627:11303]-More--viewWillAppear----

2012-12-2714:01:26.156WTV[1627:11303]-More--viewDidAppear----

2012-12-2714:01:26.157WTV[1627:11303]-Feed--viewDidDisappear----

当我们信心慢慢，庆幸我们可以了解了这两个方法时，悲剧发生了：

4.苹果官方已经把这两个方法DeprecatediniOS6.0.了

-(void)presentModalViewController:(UIViewController*)modalViewControlleranimated:(BOOL)animated;

-(void)dismissModalViewControllerAnimated:(BOOL)animated;

取而代之的是：

[selfpresentViewController:navigationController
animated:YES
completion:^(void){
//Code
}];

[selfdismissViewControllerAnimated:YES
completion:^(void){
//Code
}];

新接口的差别是提供了一个参数，允许你传入一个block。这个block的回调方法在VC的viewWillDisappear方法后调用。也就是被隐藏的VC对象被释放后运行回调。

这样做的好处：可以方便做多个UI效果之间的衔接和转换。

三十五：视图跳载的几种动画

BaiDuViewController*baiduController=[mainStoryboardinstantiateViewControllerWithIdentifier:@"baiduStoryboard"];
baiduController.modalTransitionStyle=UIModalTransitionStyleFlipHorizontal;
[selfpresentViewController:baiduControlleranimated:YEScompletion:^{

}];

UIModalTransitionStyleCoverVertical//新视图从下向上出现

UIModalTransitionStyleFlipHorizontal//以设备的长轴为中心翻转出现

UIModalTransitionStyleCrossDissolve//渐渐显示

UIModalTransitionStylePartialCurl//原视图向上卷起

三十六：JSONKit的使用方法

json开源的类库有很多，其中JSONKit库是非常简单易用而且效率又比较高的，重要的JSONKit适用于ios5.0以下的版本。

下载地址：https://github.com/johnezang/JSONKit

使用JSONKit库来解析json文件，只需要下载JSONKit.h和JSONKit.m添加到工程中，设置支持arc，在项目中buildphases中的compilesources，选择jsonkit.m然后确认键输入－fno-objc-arc

#import"JSONKit.h"

//假设strJson是网络上接收到的json字符串，
NSString*strJson=@"[{\"Id\":1,\"BrandName\":\"爱马仕\"},{\"Id\":2,\"BrandName\":\"安娜苏\"}]";
NSArray*arrlist=[strJsonobjectFromJSONString];
NSLog(@"%d",[arrlistcount]);
for(inti=0;i<[arrlistcount];i++){
NSDictionary*item=[arrlistobjectAtIndex:i];
NSString*BrandName=[itemobjectForKey:@"BrandName"];
NSLog(@"%@",BrandName);
}

字典arrlist便是解析好的json文件了。

JSONKit库也可以用来生成json文件

NSMutableDictionary*jsonDic=[NSMutableDictionarydictionary];
NSMutableDictionary*alert=[NSMutableDictionarydictionary]
;NSMutableDictionary*aps=[NSMutableDictionarydictionary];
[alertsetObject:@"amsgcome!"forKey:@"body"];
[apssetObject:alertforKey:@"alert"];
[apssetObject:@"3"forKey:@"bage"];
[apssetObject:@"def.mp3"forKey:@"sound"];
[jsonDicsetObject:apsforKey:@"aps"];
NSString*strJson=[jsonDicJSONString];

另一个，其中operation.responseString就是下面那串json字符串，通过它进行解析：

NSDictionary*resultDictionary=[operation.responseStringobjectFromJSONStringWithParseOptions:JKParseOptionLooseUnicode];
NSLog(@"%@ItemsFound!",[resultDictionaryobjectForKey:@"weatherinfo"]);
//{"weatherinfo":{"city":"北京","cityid":"101010100","temp":"3","WD":"北风","WS":"3级","SD":"24%","WSE":"3","time":"11:25","isRadar":"1","Radar":"JC_RADAR_AZ9010_JB","njd":"暂无实况","qy":"1028"}}

self.weaLableInfo.text=[NSStringstringWithFormat:@"城市：%@,温度:%@",[[resultDictionaryobjectForKey:@"weatherinfo"]objectForKey:@"city"],[[resultDictionaryobjectForKey:@"weatherinfo"]objectForKey:@"temp"]];

三十七：三十五：afnetworking2.0运用，结合json，引入afnetworking文件后，引入头文件就可以使用，支持arc

-(IBAction)JsonAction:(UIBarButtonItem*)sender{
NSString*weatherUrl=[NSStringstringWithFormat:@"%@%@.html",BaseURLString,self.UrlString];

AFHTTPRequestOperationManager*manager=[AFHTTPRequestOperationManagermanager];
manager.responseSerializer.acceptableContentTypes=[NSSetsetWithObject:@"text/html"];
[managerGET:weatherUrlparameters:nilsuccess:^(AFHTTPRequestOperation*operation,idresponseObject){

NSDictionary*resultDictionary=[operation.responseStringobjectFromJSONStringWithParseOptions:JKParseOptionLooseUnicode];
NSLog(@"%@ItemsFound!",[resultDictionaryobjectForKey:@"weatherinfo"]);
//{"weatherinfo":{"city":"北京","cityid":"101010100","temp":"3","WD":"北风","WS":"3级","SD":"24%","WSE":"3","time":"11:25","isRadar":"1","Radar":"JC_RADAR_AZ9010_JB","njd":"暂无实况","qy":"1028"}}

self.weaLableInfo.text=[NSStringstringWithFormat:@"城市：%@,温度:%@",[[resultDictionaryobjectForKey:@"weatherinfo"]objectForKey:@"city"],[[resultDictionaryobjectForKey:@"weatherinfo"]objectForKey:@"temp"]];

}failure:^(AFHTTPRequestOperation*operation,NSError*error){
NSLog(@"Error:%@",error);
}];

}

带post参数到服务端

AFHTTPRequestOperationManager*manager=[AFHTTPRequestOperationManagermanager];
//申明返回的结果是json类型
manager.responseSerializer=[AFJSONResponseSerializerserializer];
//申明请求的数据是json类型
manager.requestSerializer=[AFJSONRequestSerializerserializer];
//如果报接受类型不一致请替换一致text/html或别的
manager.responseSerializer.acceptableContentTypes=[NSSetsetWithObject:@"text/html"];
//传入的参数
NSDictionary*parameters=@{@"1":@"XXXX",@"2":@"XXXX",@"3":@"XXXXX"};
//你的接口地址
NSString*url=@"http://xxxxx";
//发送请求
[managerPOST:urlparameters:parameterssuccess:^(AFHTTPRequestOperation*operation,idresponseObject){
NSLog(@"JSON:%@",responseObject);
}failure:^(AFHTTPRequestOperation*operation,NSError*error){
NSLog(@"Error:%@",error);
}];