Question

我正在从另一个应用中启动应用并传递值。我可以将值传入AppDelegate，但我似乎无法从ViewController访问它。这是我正在使用的代码：

从应用程序1（按钮触摸调用）：

NSString* str360URL = @"customer360://?customerNum=70044321";

    BOOL canOpenURL = [[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:str360URL]];

    if (canOpenURL) {
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:str360URL]];
    }

来自App 2 AppDelegate：

- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {

    if ([[url scheme] isEqualToString:@"customer360"]) {

        //check to see if we are passing in a customer number
        if ([[url query] rangeOfString:@"customerNum"].location != NSNotFound) {

            //get all the query string items (there should be only the customer num as of 6/01/14 but just in case they want to expand what is passed in
            NSArray* arrQueryComponents = [[url query] componentsSeparatedByString:@"&"];

            //loop
            for(NSString* strThisKVPair in arrQueryComponents) {

                //split the kv pairs into parts
                NSArray* arrKVPair = [strThisKVPair componentsSeparatedByString:@"="];
                //get the value from the kv pair
                self.strCustomerNum = [arrKVPair objectAtIndex:1];

            }

        }
...

此处有更多代码用于注册目的。我可以在这里弹出一个UIAlertView并在属性self.strCustomerNum上看到正确的值，所以我知道appDelegate将它存储在它的属性中。

在ViewController中我有这段代码：

//pass in the customer number
    self.strCustomerNum = ((AppDelegate *)[UIApplication sharedApplication].delegate).strCustomerNum;
    UIAlertView* alert = [[UIAlertView alloc] initWithTitle:@"App View Controller" message:self.strCustomerNum delegate:nil cancelButtonTitle:@"ok" otherButtonTitles:nil, nil];
    [alert show];

我的提醒不会显示客户编号。正在导入AppDelegate.h。关于我在哪里出错的任何想法？

Answer 1

我最好的猜测是视图控制器中的代码在应用委托代理之前执行，因此strCustomerNum的值为零。

您可以通过在视图控制器和应用代理application:openURL:sourceApplication:annotation:

中设置断点来确认这一点

Objective-c：将值从AppDelegate传递给UIViewController

1 个答案: