WWDC2014之App Extensions学习笔记
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http://wangzz.github.io/blog/2014/06/23/wwdc2014zhi-app-extensionsxue-xi-bi-ji/
一、关于App Extensions
extension是iOS8新开放的一种对几个固定系统区域的扩展机制,它可以在一定程度上弥补iOS的沙盒机制对应用间通信的限制。
extension的出现,为用户提供了在其它应用中使用我们应用提供的服务的便捷方式,比如用户可以在Today
的widgets
中查看应用展示的简略信息,而不用再进到我们的应用中,这将是一种全新的用户体验;但是,extension的出现可能会减少用户启动应用的次数,同时还会增大开发者的工作量。
几个关键词
- extension point
系统中支持extension的区域,extension的类别也是据此区分的,iOS上共有Today
、Share
、Action
、Photo Editing
、Storage Provider
、Custom keyboard
几种,其中Today
中的extension又被称为widget
。
每种extension point的使用方式和适合干的活都不一样,因此不存在通用的extension。
- app extension
即为本文所说的extension。extension并不是一个独立的app,它有一个包含在app bundle中的独立bundle,extension的bundle后缀名是
.appex
。其生命周期也和普通app不同,这些后文将会详述。extension不能单独存在,必须有一个包含它的containing app。
另外,extension需要用户手动激活,不同的extension激活方式也不同,比如: 比如Today中的widget需要在Today中激活和关闭;
Custom keyboard
需要在设置中进行相关设置;Photo Editing
需要在使用照片时在照片管理器中激活或关闭;Storage Provider
可以在选择文件时出现;Share
和Action
可以在任何应用里被激活,但前提是开发者需要设置Activation Rules
,以确定extension需要在合适出现。- containing app
尽管苹果开放了extension,但是在iOS中extension并不能单独存在,要想提交到AppStore,必须将extension包含在一个app中提交,并且app的实现部分不能为空,这个包含extension的app就叫containing app。
extension会随着containing app的安装而安装,同时随着containing app的卸载而卸载。
- host app
能够调起extension的app被称为host app,比如
widget
的host app就是Today
。二、extension和containing app、host app
2.1 extension和host app
extension和host app之间可以通过extensionContext属性直接通信,该属性是新增加的UIViewController类别:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span>
@interface UIViewController(NSExtensionAdditions) <NSExtensionRequestHandling>// Returns the extension context. Also acts as a convenience method for a view controller to check if it participating in an extension request.@property (nonatomic,readonly,retain) NSExtensionContext *extensionContext NS_AVAILABLE_IOS(8_0);@end
实际上extension和host app之间是通过IPC(interprocess communication)实现的,只是苹果把调用接口高度抽象了,我们并不需要关注那么底层的东西。
2.2 containing app和host app
他们之间没有任何直接关系,也从来不需要通信。
2.3 extension和containing app
这二者之间的关系最复杂,纠纠缠缠扯不清关系。
- 不能直接通信
首先,尽管extension的bundle是放在containing app的bundle中,但是他们是两个完全独立的进程,之间不能直接通信。不过extension可以通过openURL的方式启动containing app(当然也能启动其它app),不过必须通过extensionContext借助host app来实现:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span>
//通过openURL的方式启动Containing APP- (void)openURLContainingAPP{ [self.extensionContext openURL:[NSURL URLWithString:@"appextension://123"] completionHandler:^(BOOL success) { NSLog(@"open url result:%d",success); }];}
extension中是无法直接使用openURL的。
- 可以共享
Shared resources
extension和containing app可以共同读写一个被称为
Shared resources
的存储区域,这是通过App Groups实现的,后文将会详述。三者间的关系可以通过官网给的两张图片形象地说明:
- containing app能够控制extension的出现和隐藏
通过以下代码,containing app可以让extension出现或隐藏(当然extension也可以让自己隐藏):
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">9</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">10</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">11</span>
//让隐藏的插件重新显示- (void)showTodayExtension{ [[NCWidgetController widgetController] setHasContent:YES forWidgetWithBundleIdentifier:@"com.wangzz.app.extension"];}//隐藏插件- (void)hiddeTodayExtension{ [[NCWidgetController widgetController] setHasContent:NO forWidgetWithBundleIdentifier:@"com.wangzz.app.extension"];}
三、App Groups
这是iOS8新开放的功能,在OS X上早就可用了。它主要用于同一group下的app共享同一份读写空间,以实现数据共享。
extension和containing app共同读写一份数据是很合理的需求,比如系统的股市应用,widget和app中都需要展示几个公司的股票数据,这就可以通过App Groups实现。
3.1 功能开启
为了便于后续操作,请先确保你的开发者账号在Xcode上处于登录状态。
- 在app中开启
App Groups位于:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span>
TARGETS-->AppExtensionDemo-->Capabilities-->App Groups
找到以后,将App Groups右上角的开关打开,然后选择添加groups,比如我的是group.wangzz,当然这是为了测试随便起得名字,正规点得命名规则应该是:group.com.company.app。
添加成功以后如下图所示:
- 在extension中开启
我创建的是widget,target名称为TodayExtension,对应的App Groups位于:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span>
TARGETS-->TodayExtension-->Capabilities-->App Groups
开启方式和app中一样,需要注意的是必须保证这里地App Groups名称和app中的相同,即为group.wangzz。
四、extension和containing app数据共享
App Groups给我们提供了同一group内app可以共同读写的区域,可以通过以下方式实现数据共享:
4.1 通过NSUserDefaults共享数据
- 存数据
通过以下方式向NSUserDefaults中保存数据:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span>
- (void)saveTextByNSUserDefaults{ NSUserDefaults *shared = [[NSUserDefaults alloc] initWithSuiteName:@"group.wangzz"]; [shared setObject:_textField.text forKey:@"wangzz"]; [shared synchronize];}
需要注意的是:
1.保存数据的时候必须指明group id;
2.而且要注意NSUserDefaults能够处理的数据只能是可plist化的对象,详情见Property List Programming Guide。
3.为了防止出现数据同步问题,不要忘记调用
[shared synchronize];
- 读数据
对应的读取数据方式:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span>
- (NSString *)readDataFromNSUserDefaults{ NSUserDefaults *shared = [[NSUserDefaults alloc] initWithSuiteName:@"group.wangzz"]; NSString *value = [shared valueForKey:@"wangzz"]; return value;}
4.2 通过NSFileManager共享数据
NSFileManager在iOS7提供了containerURLForSecurityApplicationGroupIdentifier方法,可以用来实现app group共享数据。
- 保存数据
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">9</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">10</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">11</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">12</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">13</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">14</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">15</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">16</span>
- (BOOL)saveTextByNSFileManager{ NSError *err = nil; NSURL *containerURL = [[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:@"group.wangzz"]; containerURL = [containerURL URLByAppendingPathComponent:@"Library/Caches/good"]; NSString *value = _textField.text; BOOL result = [value writeToURL:containerURL atomically:YES encoding:NSUTF8StringEncoding error:&err]; if (!result) { NSLog(@"%@",err); } else { NSLog(@"save value:%@ success.",value); } return result;}
- 读数据
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">9</span>
- (NSString *)readTextByNSFileManager{ NSError *err = nil; NSURL *containerURL = [[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:@"group.wangzz"]; containerURL = [containerURL URLByAppendingPathComponent:@"Library/Caches/good"]; NSString *value = [NSString stringWithContentsOfURL:containerURL encoding:NSUTF8StringEncoding error:&err]; return value;}
在这里我试着保存和读取的是字符串数据,但读写SQlite我相信也是没问题的。
- 数据同步
两个应用共同读取同一份数据,就会引发数据同步问题。WWDC2014的视频中建议使用NSFileCoordination实现普通文件的读写同步,而数据库可以使用CoreData,Sqlite也支持同步。
五、extension和containing app代码共享
和数据共享类似,extension和containing app很自然地会有一些业务逻辑上可以共用的代码,这时可以通过iOS8中刚开放使用的framework实现。苹果在App Extension Programming Guide中是这样描述的:
In iOS 8.0 and later, you can use an embedded framework to share code between your extension and its containing app. For example, if you develop image-processing code that you want both your Photo Editing extension and its containing app to share, you can put the code into a framework and embed it in both targets.
即将framework分别嵌入到extension和containing app的target中实现代码共享。但这样岂不是需要分别要将framework分别copy到extension和containing app的main bundle中?
参考extension和containing app数据共享,我试想能不能将framework只保存一份放在App Groups区域?
5.1 copy framework到App Groups
在app首次启动的时候将framework放到App Groups区域:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">9</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">10</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">11</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">12</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">13</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">14</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">15</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">16</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">17</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">18</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">19</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">20</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">21</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">22</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">23</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">24</span>
- (BOOL)copyFrameworkFromMainBundleToAppGroup{ NSFileManager *manager = [NSFileManager defaultManager]; NSError *err = nil; NSURL *containerURL = [[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:@"group.wangzz"]; NSString *sorPath = [NSString stringWithFormat:@"%@/Dylib.framework",[[NSBundle mainBundle] bundlePath]]; NSString *desPath = [NSString stringWithFormat:@"%@/Library/Caches/Dylib.framework",containerURL.path]; BOOL removeResult = [manager removeItemAtPath:desPath error:&err]; if (!removeResult) { NSLog(@"%@",err); } else { NSLog(@"remove success."); } BOOL copyResult = [[NSFileManager defaultManager] copyItemAtPath:sorPath toPath:desPath error:&err]; if (!copyResult) { NSLog(@"%@",err); } else { NSLog(@"copy success."); } return copyResult;}
5.2 使用framework:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">9</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">10</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">11</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">12</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">13</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">14</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">15</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">16</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">17</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">18</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">19</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">20</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">21</span>
- (BOOL)loadFrameworkInAppGroup{ NSError *err = nil; NSURL *containerURL = [[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:@"group.wangzz"]; NSString *desPath = [NSString stringWithFormat:@"%@/Library/Caches/Dylib.framework",containerURL.path]; NSBundle *bundle = [NSBundle bundleWithPath:desPath]; BOOL result = [bundle loadAndReturnError:&err]; if (result) { Class root = NSClassFromString(@"Person"); if (root) { Person *person = [[root alloc] init]; if (person) { [person run]; } } } else { NSLog(@"%@",err); } return result;}
经过测试,竟然能够加载成功。
需要说明的是,这里只是说那么用是可以成功加载framework,但还面临不少问题,比如如果用户在启动app之前去使用extension,这时framework还没有copy过去,怎么处理;另外iOS的机制或者苹果的审核是否允许这样使用等。
在一切确定下来之前还是乖乖按文档中的方式使用吧。
六、生命周期
extension和普通app的最大区别之一是生命周期。
- 开始
在用户通过host app点击extension时,系统就会实例化extension应用,这是生命周期的开始。
- 执行任务
在extension启动以后,开始执行它的使命。
- 终止
在用户取消任务,或者任务执行结束,或者开启了一个长时后台任务时,系统会将其杀掉。
由此可见,extension就是为了任务而生!
下图来自官方文档,它将生命周期划分的更详细:
通过打印日志发现,
Today
中的widget
在将Today
切换到全部
或者未读通知时
都会被杀掉。七、 调试
extension和普通app的调试方式差不多,开始调试前先选中extension对应的target,点击run,就会弹出下图所示选择框:
需要选择一个host app,这里选择
Today
。然后即可和普通app一样调试了,不过我在实际使用过程中,发现有各种奇怪的事情,比如NSLog无法在控制台输出,应该是bug吧。
八、 iOS8应用文件系统
发现iOS8的文件系统发生了变化,新的文件系统将可执行文件(即原来的.app文件)从沙盒中移到了另外一个地方,这样感觉更合理。
- 测试代码
下述代码用于打印App Groups路径、应用的可执行文件路径、对应的Documents路径:
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">7</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">8</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">9</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">10</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">11</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">12</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">13</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">14</span>
- (void)logAppPath{ //app group路径 NSURL *containerURL = [[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:@"group.wangzz"]; NSLog(@"app group:\n%@",containerURL.path); //打印可执行文件路径 NSLog(@"bundle:\n%@",[[NSBundle mainBundle] bundlePath]); //打印documents NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *path = [paths objectAtIndex:0]; NSLog(@"documents:\n%@",path);}
- containing app执行结果
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span>
2014-06-23 19:35:03.944 AppExtensionDemo[7471:365131] app group:/private/var/mobile/Containers/Shared/AppGroup/89CCBFB1-CA5E-4C7F-80CB-A3EB9E8418162014-06-23 19:35:03.946 AppExtensionDemo[7471:365131] bundle:/private/var/mobile/Containers/Bundle/Application/1AC73797-A3BB-4BDE-A647-3D083DA6871A/AppExtensionDemo.app2014-06-23 19:35:03.948 AppExtensionDemo[7471:365131] documents:/var/mobile/Containers/Data/Application/E5E6E516-0163-4754-9D10-A5F6C33A6261/Documents
- extension执行结果
<span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">1</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">2</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">3</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">4</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">5</span><span class="line-number" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; color: rgb(88, 110, 117) !important;">6</span>
Jun 23 19:37:49 autonavis-iPad com.foogry.AppExtensionDemo.TodayExtension[7638] <Warning>: app group: /private/var/mobile/Containers/Shared/AppGroup/89CCBFB1-CA5E-4C7F-80CB-A3EB9E841816Jun 23 19:37:49 autonavis-iPad com.foogry.AppExtensionDemo.TodayExtension[7638] <Warning>: bundle: /private/var/mobile/Containers/Bundle/Application/596717B7-7CB8-4F53-BCD4-380F34ABD30F/AppExtensionDemo.app/PlugIns/com.foogry.AppExtensionDemo.TodayExtension.appexJun 23 19:37:49 autonavis-iPad com.foogry.AppExtensionDemo.TodayExtension[7638] <Warning>: documents: /var/mobile/Containers/Data/PluginKitPlugin/57581433-3DBD-4930-971F-78D30C150E8A/Documents
由此可见,不管是extension还是containing app,他们的可执行文件和保存数据的目录都是分开存放的,即所有app的可执行文件都放在一个大目录下,保存数据的目录保存在另一个大目录下,同样,AppGroup放在另一个大目录下。
说明
本文用到的demo已经上传到github上。
文中可能有理解有误的地方,还请指出。
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