[英]Why do I get a type mismatch for a map as a routing parameter?
I am using the playframework 2.3.8 and have a view-class. 我正在使用playframework 2.3.8,并具有一个视图类。 In there a is button:
在其中有一个按钮:
<button class="btn btn-default" type="button" onclick="@routes.Application.sendMap(myMap)" method="POST">Send</button>
I want to append a question / answer pair to the map in my controller class (Application.java): 我想在控制器类(Application.java)中的地图上添加一个问题/答案对:
public static Result sendMap(Map<Question, List<Answer>> sendMap){
Question question4 = new Question("ertw", "SendMap Question?", 34, "Tim");
Answer answer41 = new Answer("werw", "ertw", "SendMap Answer 1!", 12, "Oliver");
Answer answer42 = new Answer("tzsdfu", "ertw", "SendMap Answer 2!", 1, "Marcus");
List<Answer> answerList4 = new ArrayList<Answer>();
answerList4.add(answer41);
answerList4.add(answer42);
sendMap.put(question4, answerList4);
return ok(views.html.frageAntwort.render(sendMap));
}
In my routes.conf I have added the route to the controller class and use Map
as the parameter: 在我的routes.conf中,我已将路由添加到控制器类,并使用
Map
作为参数:
POST /QuestionMap controllers.Application.sendMap(Map)
But now I get the error: 但是现在我得到了错误:
type mismatch; found : String required: java.util.Map[model.Question,java.util.List[model.Answer]]
Why does the map get converted into a string? 为什么将地图转换为字符串?
Default parameters type is String: "For parameters of type String, the parameter type is optional." 默认参数类型为String:“对于String类型的参数,参数类型是可选的。” Documentation Play .
文件播放 。 You can also take a look there: How to create Map - post on Stack Overflow .
您也可以在这里看看: 如何在Stack Overflow上创建Map-post 。 You should create correct template and then pass it through the parameter in your method on the configuration file
您应该创建正确的模板,然后将其通过配置文件中方法中的参数传递
I've got it almost completely working now ... altough I dont completely understand how: 我现在几乎可以完全使用它了 ……尽管我还不完全了解如何:
My button in the view-class, now without any parameter 我的按钮在视图类中,现在没有任何参数
<a href="@routes.Application.sendMap()"><button class="btn btn-default" type="button">Absenden</button>
My controller-class now correctly puts another fake question/answer pair into the map and then returns it with the changed map to the index.scala.html: 我的控制器类现在可以正确地将另一个伪造的问题/答案对放入地图中,然后将其与更改后的地图一起返回到index.scala.html:
return ok(views.html.index.render(myMap));
The most important part happens in routes.conf: 最重要的部分发生在routes.conf中:
GET / controllers.Application.index()
GET /Fragenliste controllers.Application.sendMap()
GET /FrageStellen controllers.Application.askQuestion()
GET /Einstellungen controllers.Application.showSettings()
GET /Quiz controllers.Application.startQuiz()
sendMap() now has no parameters and points to another site named /Fragenliste
. sendMap()现在没有参数,并且指向另一个名为
/Fragenliste
站点。 And there is the part I dont fully understand - if I use 还有我不完全理解的部分-如果我使用
GET / controllers.Application.sendMap()
it points to the index()-method in Application.java. 它指向Application.java中的index()方法。 In there I have another method called initialize():
在那里,我有另一个名为initialize()的方法:
public static Result index() {
initialize();
(...)
}
public static void initialize() {
Question question1 = new Question("xyz", "Do Androids dream?", 127, "Marcus");
Answer answer11 = new Answer("zab", "xyz", "Only of electric sheep!", 70, "Tibor");
Answer answer12 = new Answer("qwert", "xyz", "No, they dont!", 10, "Sarah");
List<Answer> answerList1 = new ArrayList<Answer>();
answerList1.add(answer11);
answerList1.add(answer12);
myMap.clear();
myMap.put(question1, answerList1);
}
In this the map gets constructed, after I cleared potential rests of old maps. 在此之后,我清除了旧地图的其余部分后,就可以构建地图。 So my route points to the index and now the new question does not get added!
因此,我的路线指向了索引,现在没有添加新问题! Why cant I point to the index aswell and still have it work?
为什么我也不能指向索引,但仍然可以正常工作?
Basically: 基本上:
mysite.com/ = index ... user presses button for new question, gets transfered to
mysite.com/enterQuestion ... user enters question and hits "submit", gets transfered to
mysite.com/ = index
My solution for the moment is: 我目前的解决方案是:
mysite.com/ = index ... user presses button for new question, gets transfered to
mysite.com/enterQuestion ... user enters question and hits "submit", gets transfered to
mysite.com/ANOTHER_SITE != index, but looks and works exactly like the index!
Is there a way to do so? 有办法吗? If yes, my problem would be fully solved.
如果是,我的问题将得到彻底解决。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.