Play Framework compilation error when passing List object from controller to view

Question

I have a function in a controller that returns a list of User model records - I am using the PlayStartApp template:

public Result getAllUsers() {
    List<User> users = User.find.all();
    return ok(searchusers.render(form(Login.class, users)));
}

This function works correctly and returns a List object.

I also have a view (html page) set with this to pass the object to the view:

@(loginForm: Form[Application.Login], userList: java.util.List[User])

When I compile in activator on the command line, I receive this error message:

[PlayStartApp] $ compile
[info] Compiling 1 Scala source and 1 Java source to C:\WebDev\git\PlayAuthentic
ate\target\scala-2.10\classes...
[error] C:\WebDev\git\PlayAuthenticate\app\controllers\Application.java:209: met
hod render in class views.html.searchusers cannot be applied to given types;
[error]   required: play.data.Form<controllers.Application.Login>,java.util.List
<models.User>
[error]   found: play.data.Form<controllers.Application.Login>
[error]   reason: actual and formal argument lists differ in length
[error] searchusers.render
[error] C:\WebDev\git\PlayAuthenticate\app\controllers\Application.java:215: no
suitable method found for form(java.lang.Class<controllers.Application.Login>,ja
va.util.List<models.User>)
[error]     method play.data.Form.<T>form(java.lang.Class<T>,java.lang.Class<?>)
 is not applicable
[error]       (cannot infer type-variable(s) T
[error]         (argument mismatch; java.util.List<models.User> cannot be conver
ted to java.lang.Class<?>))
[error]     method play.data.Form.<T>form(java.lang.String,java.lang.Class<T>,ja
va.lang.Class<?>) is not applicable
[error]       (cannot infer type-variable(s) T
[error]         (actual and formal argument lists differ in length))
[error]     method play.data.Form.<T>form(java.lang.String,java.lang.Class<T>) i
s not applicable
[error]       (cannot infer type-variable(s) T
[error]         (argument mismatch; java.lang.Class<controllers.Application.Logi
n> cannot be converted to java.lang.String))
[error]     method play.data.Form.<T>form(java.lang.Class<T>) is not applicable
[error]       (cannot infer type-variable(s) T
[error]         (actual and formal argument lists differ in length))
[error] form
[info] Some messages have been simplified; recompile with -Xdiags:verbose to get
 full output
[error] (compile:compileIncremental) javac returned nonzero exit code

I reviewed this post, but I am still having the same issue: Play Framework 2.2.1 - Compilation error: "method render in class index cannot be applied to given types;"

Any help would be great!

EDIT: I removed the Login form. Code is now:

public Result getAllUsers() {
    List<User> users = User.find.all();
    return ok(searchusers.render(users));
}

My view now has:

@(userList: List[User])


@main(null) {

<ul>
@for(user <- userList) {
  <li>@user.fullname</li>
} 
</ul>

}

I am receiving this when compiling:

[error] C:\WebDev\git\PlayAuthenticate\app\controllers\Application.java:209:  no
 instance(s) of type variable(s) T exist so that play.data.Form<T> conforms to java.util.List<models.User>

pamu pamu · Accepted Answer · 2016-11-03T19:58:23

Change this line

ok(searchusers.render(form(Login.class, users)))

to

ok(searchusers.render(form(Login.class), users))

For clarity sake

Form[Application.Login] loginForm = form(Login.class)

ok(searchusers.render(loginForm, users))

You have to pass form as first argument and users as second argument, but you are trying to pass Login.class and users to form which is wrong.

Play Framework compilation error when passing List object from controller to view

1 Answers