ios,todayExtension

扩展（Extension）是iOS 8中引入的一个非常重要的新特性。扩展让app之间的数据交互成为可能。用户可以在app中使用其他应用提供的功能，而无需离开当前的应用。iOS 8系统有6个支持扩展的系统区域，分别是Today、Share、Action、Photo Editing、Storage Provider、Custom keyboard。支持扩展的系统区域也被称为扩展点。对于赛事比分，股票、天气、快递这类需要实时获取的信息，可以在通知中心的Today视图中创建一个Today扩展实现。Today扩展又称为Widget。本文主要是介绍Today Extension的用法。

创建步骤1、选择File–>New–>Target创建一个新的Target，如下图所示：iOS8_today_extension2、选择Application Extension–>Today Extension（下图中最后一个），指定需要创建的Extension的类型，这里选择Today Extension，如下图所示：ios8_today_extension3、按照要求填写Product Name、Organization Name和Language，如下图所示：ios8_today_extension4、点击Finish后Xcode会提示是否需要立即激活当前创建的Scheme，默认选择cancel就行了，Xcode会自动创建一个Today Extension的Target，默认会创建如下几个文件：TodayViewController.h/TodayViewController.mMainInterface.storyboardSupporting Files/Info.plist5、启动应用后在通知中心添加就能看到运行效果，如下图所示：ios8_today_extension_004.png开发实例1、配置Info.plist文件，使用代码布局Xcode6中新建的Today Extension默认是使用StoryBoard布局的，如果需要使用代码布局就需要配置Info.plist文件，步骤如下：（1）删除NSExtensionMainStoryboard的配置，如下所示：12NSExtensionMainStoryboardMainInterface（2）添加NSExtensionPrincipalClass的配置，如下所示：12NSExtensionPrincipalClassTodayViewController（3）修改CFBundleDisplayName，调整Widget显示的名称12CFBundleDisplayName显示的名称2、调整Widget的高度self.preferredContentSize = CGSizeMake(0, 200);取消widget默认的inset，让应用靠左1234- (UIEdgeInsets)widgetMarginInsetsForProposedMarginInsets:(UIEdgeInsets)defaultMarginInsets{    return UIEdgeInsetsZero;}3、示例运行效果如下：ios8_today_extension_005.png布局代码如下：【以下代码使用了Masonry来进行AutoLayout处理】

 (void)makeView{    __weak __typeof(&*self)ws = self;    //内容视图    self.contentView = [UIView new];    self.contentView.backgroundColor = [UIColor clearColor];    [self.view addSubview:self.contentView];    self.contentView.userInteractionEnabled = YES;    [self.contentView mas_makeConstraints:^(MASConstraintMaker *make) {        make.edges.equalTo(ws.view);        make.height.mas_equalTo(@44).priorityHigh();    }];    //Label1    self.priceLabel = [UILabel new];    self.priceLabel.textColor = [UIColor colorWithRed:66.0/255 green:145.0/255 blue:211.0/255 alpha:1];    self.priceLabel.text = @"$592.12";    [self.contentView addSubview:self.priceLabel];    [self.priceLabel mas_makeConstraints:^(MASConstraintMaker *make) {        make.left.equalTo(ws.contentView.mas_left).with.offset(20);        make.top.equalTo(ws.contentView.mas_top).with.offset(10);        make.size.mas_equalTo(CGSizeMake(62, 21));    }];    //切换按钮    self.toggleLineChartButton = [UIButton buttonWithType:UIButtonTypeCustom];    [self.contentView addSubview:self.toggleLineChartButton];    [self.toggleLineChartButton addTarget:self action:@selector(toggleLineChartViewVisible:) forControlEvents:UIControlEventTouchUpInside];    [self.toggleLineChartButton setImage:[UIImage imageNamed:@"caret-notification-center"] forState:UIControlStateNormal];    [self.toggleLineChartButton mas_makeConstraints:^(MASConstraintMaker *make) {        make.right.equalTo(ws.contentView.mas_right).with.offset(0);        make.top.equalTo(ws.contentView.mas_top).with.offset(0);        make.size.mas_equalTo(CGSizeMake(44, 44));    }];    //Label2    self.priceChangeLabel = [UILabel new];    self.priceChangeLabel.textColor = [UIColor colorWithRed:133.0/255 green:191.0/255 blue:37.0/255 alpha:1];    self.priceChangeLabel.text = @"+1.23";    [self.contentView addSubview:self.priceChangeLabel];    [self.priceChangeLabel mas_makeConstraints:^(MASConstraintMaker *make) {        make.right.equalTo(ws.toggleLineChartButton.mas_left).with.offset(-20);        make.top.equalTo(ws.contentView).with.offset(10);        make.size.mas_equalTo(CGSizeMake(44, 21));    }];    //Label3    self.detailLabel = [[UILabel alloc] init];    self.detailLabel.backgroundColor = [UIColor clearColor];    self.detailLabel.numberOfLines = 0;    [self.contentView addSubview:self.detailLabel];    self.detailLabel.text = @"\n\n详细信息";    self.detailLabel.textAlignment = NSTextAlignmentCenter;    [self.detailLabel mas_makeConstraints:^(MASConstraintMaker *make) {        make.top.equalTo(ws.priceLabel.mas_bottom).with.offset(0);        make.left.equalTo(ws.contentView);        make.width.equalTo(ws.contentView);        if(self.lineChartIsVisible)        {            self.detailLabel.textColor = [UIColor whiteColor];            make.height.mas_equalTo(@98);        }        else        {            self.detailLabel.textColor = [UIColor clearColor];            make.height.mas_equalTo(@0);        }    }];}

按钮点击处理：- (void)toggleLineChartViewVisible:(id)sender{    __weak __typeof(&*self)ws = self;    //重新布局    if(self.lineChartIsVisible)    {        self.preferredContentSize = CGSizeMake(0, 44);        [self.detailLabel mas_remakeConstraints:^(MASConstraintMaker *make) {            make.height.mas_equalTo(@0);            ws.detailLabel.textColor = [UIColor clearColor];            ws.detailLabel.textAlignment = NSTextAlignmentCenter;        }];        //改变按钮的方向        self.toggleLineChartButton.transform = CGAffineTransformMakeRotation(0);        self.lineChartIsVisible = NO;        [self.contentView mas_updateConstraints:^(MASConstraintMaker *make) {            make.height.mas_equalTo(@44).priorityHigh();        }];    }    else    {        self.preferredContentSize = CGSizeMake(0, 142);        [self.detailLabel mas_remakeConstraints:^(MASConstraintMaker *make) {            make.height.mas_equalTo(@98);            ws.detailLabel.textColor = [UIColor whiteColor];            ws.detailLabel.textAlignment = NSTextAlignmentCenter;        }];        //改变按钮的方向        self.toggleLineChartButton.transform = CGAffineTransformMakeRotation(180.0 * M_PI/180.0);        self.lineChartIsVisible = YES;        [self.contentView mas_updateConstraints:^(MASConstraintMaker *make) {            make.height.mas_equalTo(@142).priorityHigh();        }];    }}

代码：https://github.com/pony2323/TodayExtention