首页 > 代码库 > iOS UIAlertController
iOS UIAlertController
在Xcode的iOS9.0 SDK中,UIAlertView和UIActionSheet都被UIAlertController取代。
在iOS 9中,UIAlertController在功能上是和UIAlertView以及UIActionSheet相同的,UIAlertController以一种模块化替换的方式来代替这两货的功能和作用。是使用对话框(alert)还是使用上拉菜单(action sheet),就取决于在创建控制器时,您是如何设置首选样式的。
1、对话框
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"标题"message:@"这个是UIAlertController的默认样式"preferredStyle:UIAlertControllerStyleAlert]; [self presentViewController:alertController animated:YES completion:nil];
同创建UIAlertView相比,我们无需指定代理,也无需在初始化过程中指定按钮。不过要特别注意第三个参数,要确定您选择的是对话框样式还是上拉菜单样式。
2、将动作按钮添加到控制器
通过创建UIAlertAction的实例,您可以将动作按钮添加到控制器上。UIAlertAction由标题字符串、样式以及当用户选中该动作时运行的代码块组成。通过UIAlertActionStyle,您可以选择如下三种动作样式:常规(default)、取消(cancel)以及警示(destruective)。为了实现原来我们在创建UIAlertView时创建的按钮效果,我们只需创建这两个动作按钮并将它们添加到控制器上即可。
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"标题"message:@"这个是UIAlertController的默认样式"preferredStyle:UIAlertControllerStyleAlert]; UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil]; UIAlertAction *okAction = [UIAlertAction actionWithTitle:@"好的" style:UIAlertActionStyleDefault handler:nil]; [alertController addAction:cancelAction]; [alertController addAction:okAction]; [self presentViewController:alertController animated:YES completion:nil];
3、“警示”样式
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"标题"message:@"这个是UIAlertController的默认样式"preferredStyle:UIAlertControllerStyleAlert]; UIAlertAction *resetAction = [UIAlertAction actionWithTitle:@"重置" style:UIAlertActionStyleDestructive handler:nil]; UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil]; //添加顺序和显示顺序相同 [alertController addAction:cancelAction]; [alertController addAction:resetAction]; [self presentViewController:alertController animated:YES completion:nil];
4、文本对话框
设置输入框,并且设置通知,检测输入字符长度少于3时,不能点击“好的”。
值得注意的是,不像使用UIAlertView的时候可以用UIAlertViewDelegate检测文本框输入,UIAlertController没有对应的代理,只能自己实现监听。
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"文本对话框" message:@"登录和密码对话框示例" preferredStyle:UIAlertControllerStyleAlert]; [alertController addTextFieldWithConfigurationHandler:^(UITextField *textField){ [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(alertTextFieldDidChange:) name:UITextFieldTextDidChangeNotification object:textField]; textField.placeholder = @"登录"; }]; [alertController addTextFieldWithConfigurationHandler:^(UITextField *textField) { [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(alertTextFieldDidChange:) name:UITextFieldTextDidChangeNotification object:textField]; textField.placeholder = @"密码"; textField.secureTextEntry = YES; }]; UIAlertAction *okAction = [UIAlertAction actionWithTitle:@"好的" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) { UITextField *login = alertController.textFields.firstObject; UITextField *password = alertController.textFields.lastObject; NSLog(@"%@",login.text); NSLog(@"%@",password.text); }]; UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil]; [alertController addAction:cancelAction]; [alertController addAction:okAction]; [self presentViewController:alertController animated:YES completion:nil];
- (void)alertTextFieldDidChange:(NSNotification *)notification{ UIAlertController *alertController = (UIAlertController *)self.presentedViewController; if (alertController) { UITextField *login = alertController.textFields.firstObject; UIAlertAction *okAction = alertController.actions.lastObject; okAction.enabled = login.text.length > 2; } }
5、上拉菜单
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"保存或删除数据" message:@"删除数据将不可恢复" preferredStyle: UIAlertControllerStyleActionSheet]; UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * action) { NSLog(@"点击了取消"); }]; UIAlertAction *deleteAction = [UIAlertAction actionWithTitle:@"删除" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * action) { NSLog(@"点击了删除"); }]; UIAlertAction *archiveAction = [UIAlertAction actionWithTitle:@"保存" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) { NSLog(@"点击了保存"); }]; [alertController addAction:cancelAction]; [alertController addAction:deleteAction]; [alertController addAction:archiveAction]; [self presentViewController:alertController animated:YES completion:nil];
iOS UIAlertController