UIAlertController封装工具之ABAlertHelper

在iOS8之前苹果的弹框UI控件是UIAlertView，它继承于UIView，只要调用它的实例方法- (void)show;就能随时对地的弹出一个选择框。
然后在iOS8之后，苹果抛弃了UIAlertView，转而推荐使用UIAlertController。UIAlertController整合了iOS8之前的UIAlertView和UIActionSheet，
通过UIAlertControllerStyle枚举类型来初始化UIAlertView或者ActionSheet

typedef NS_ENUM(NSInteger, UIAlertControllerStyle) {
    UIAlertControllerStyleActionSheet = 0,
    UIAlertControllerStyleAlert
} NS_ENUM_AVAILABLE_IOS(8_0);

使用方法也很简单，就不细说了。但是一般来说，工程里面用到了弹框UI的话，如果每次都要写一堆重复的代码对我来说是不科学的，程序猿的宗旨是省事。所以就必须把UIAlertController的展示搞得像UIAlertView那么省事，传入需要展示的参数，直接一个show就能展示。于是就有了下面的工具类。

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>

@interface ABAlertHelper : NSObject

/**
 Alert

 @param title 标题
 @param message 内容信息
 @param cancelActiontitle 取消按钮标题
 @param destructiveActionTitle 强调红色警示按钮标题
 @param actionClick 按钮点击Block回调
 @param otherActionTitles 其他按钮标题
 */
+ (void)alertWithTitle:(NSString *)title message:(NSString *)message cancelActionTitle:(NSString *)cancelActiontitle destructiveActionTitle:(NSString *)destructiveActionTitle actionClick:(void(^)(UIAlertAction *action, NSInteger index))actionClick otherActionTitles:(NSString *)otherActionTitles,...NS_REQUIRES_NIL_TERMINATION;

/**
 ActionSheet

 @param title 标题
 @param message 内容信息
 @param cancelActiontitle 取消按钮标题
 @param otherActionTitles 其他标题
 @param actionClick 按钮点击Block回调
 */
+ (void)actionSheetWithTitle:(NSString *)title message:(NSString *)message cancelActionTitle:(NSString *)cancelActiontitle otherActionTitles:(NSArray *)otherActionTitles actionClick:(void (^)(UIAlertAction *action, NSInteger index))actionClick;

#import "ABAlertHelper.h"

@implementation ABAlertHelper

+ (UIViewController *)topViewController
{
    UIViewController *rootVC = [UIApplication sharedApplication].keyWindow.rootViewController;
    UIViewController *topVC = rootVC;
    while (topVC.presentedViewController) {
        topVC = topVC.presentedViewController;
    }
    return topVC;
}

+ (void)alertWithTitle:(NSString *)title message:(NSString *)message cancelActionTitle:(NSString *)cancelActiontitle destructiveActionTitle:(NSString *)destructiveActionTitle actionClick:(void (^)(UIAlertAction *action,NSInteger index))actionClick otherActionTitles:(NSString *)otherActionTitles, ...
{
    NSMutableArray *actions = [NSMutableArray array];
    
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
    
    if (cancelActiontitle) {
        UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:cancelActiontitle style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            if (actionClick) {
                actionClick(action,0);
            }
        }];
        [actions addObject:cancelAction];
    }
    
    if (destructiveActionTitle) {
        UIAlertAction *destructiveAction = [UIAlertAction actionWithTitle:destructiveActionTitle style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnull action) {
            if (actionClick) {
                actionClick(action,-1);
            }
        }];
        [actions addObject:destructiveAction];
    }
    
    //遍历列表
    va_list args;
    id arg = nil;
    
    //num记录action的位置
    int num = 1;

    //先把第一个存入数组
    if (otherActionTitles) {
        UIAlertAction *otherAction = [UIAlertAction actionWithTitle:otherActionTitles style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            if (actionClick) {
                actionClick(action,num);
            }
        }];
        [actions addObject:otherAction];
        
        //扫描参数列表
        va_start(args,otherActionTitles);
        while ((arg = va_arg(args, id))) {
            if ([arg isKindOfClass:[NSString class]]) {
                num ++;
                //创建action
                otherAction =  [UIAlertAction actionWithTitle:arg style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
                    if (actionClick) {
                        actionClick(action,num);
                    }
                }];
                [actions addObject:otherAction];
            }
            else {
                break;
            }
        }
        va_end(args);
    }
    
    for (UIAlertAction *action in actions) {
        [alertController addAction:action];
        if (IS_IOS9_ABOVE) {
            if (destructiveActionTitle && action.style == UIAlertActionStyleDestructive) {
                alertController.preferredAction = action;
            }
        }
    }
    
    [[ABAlertHelper topViewController] presentViewController:alertController animated:YES completion:nil];
}

+ (void)actionSheetWithTitle:(NSString *)title message:(NSString *)message cancelActionTitle:(NSString *)cancelActiontitle otherActionTitles:(NSArray *)otherActionTitles actionClick:(void (^)(UIAlertAction *action,NSInteger index))actionClick
{
    if (cancelActiontitle.length <= 0 && otherActionTitles.count == 0) {
        return;
    }
    
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleActionSheet];
    
    if (cancelActiontitle) {
        UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:cancelActiontitle style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
            if (actionClick) {
                actionClick(action,0);
            }
        }];
        [alertController addAction:cancelAction];
    }
    
    for (NSInteger num = 0; num < otherActionTitles.count; num ++) {
        NSString *otherTitle = otherActionTitles[num];
        UIAlertAction *otherAction = [UIAlertAction actionWithTitle:otherTitle style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            if (actionClick) {
                actionClick(action,num + 1);
            }
        }];
        [alertController addAction:otherAction];
    }
    
    [[ABAlertHelper topViewController] presentViewController:alertController animated:YES completion:nil];
}

这里的+ (UIViewController *)topViewController是为了找出当前最顶层的控制器，用来presentViewController模态弹出UIAlertController。
使用也很简单，看例子

[ABAlertHelper alertWithTitle:YTLocalizedString(@"定位服务未开启") message:YTLocalizedString(@"请在系统设置中开启定位服务") cancelActionTitle:YTLocalizedString(@"暂不") destructiveActionTitle:nil actionClick:^(UIAlertAction *action, NSInteger index) {
            if (index == 1) {
                NSURL *openUrl = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
                if ([[UIApplication sharedApplication] canOpenURL:openUrl]) {
                    [[UIApplication sharedApplication] openURL:openUrl];
                }
            }
        } otherActionTitles:YTLocalizedString(@"去设置"), nil];