I want to add a HashMap Object contains many different object(s) to the twirl template, because I do not like adding one by one as parameter to the twirl, it breaks the rule with design patterns.
the normal style:
views.html.index.render(object1, object2, list3, list4, ...);
@(object1:Object1Model, object2:Object2Model, list3: List[Object3Model], list4: List[Object4Model])
Is there any solution to set and get parameters like this?
Map data = new HashMap();
data.put("object1", object1);
data.put("object2", object2);
data.put("list3", list3);
data.put("list4", list4);
views.html.index.render(data);
How to get and define the objects in HashMap in twirl, the official twirl document is too simple...
@(data:Map)
Object1Model object1 = (Object1Model) data.get("object1");
Object2Model object2 = (Object2Model) data.get("object2");
List list3 = (List) data.get("list3");
List list4 = (List) data.get("list4");
Many thanks!
For type-safety you can create a dedicated class with fields of required types, the additional benefit is that sophisticated IDEs will recognize types of the fields and/or autocomplete field names, so it help you to prevent mistakes in the views.
Of course as in each class you can also use the benefits of constructor and/or getters/setters.
(pseudo code):
package viewhelpers;
import java.util.ArrayList;
import java.util.List;
public class SomeViewHelper {
public String header;
public List<String> labels = new ArrayList<>();
public List<Integer> values = new ArrayList<>();
}
Fill it in controller somehow:
public static Result incomes() {
SomeViewHelper data = new SomeViewHelper();
data.header = "Incomes in first quarter";
data.labels = Arrays.asList("Jan", "Feb", "Mar");
data.values = Arrays.asList(121, 122, 123);
return ok(views.html.incomes.render(data));
}
and use in the view like:
@(data: viewhelpers.SomeViewHelper)
<h1>@data.header</h1>
<table>
<tr>
@for(label <- data.labels) {
<th>@label</th>
}
</tr>
<tr>
@for(value <- data.values) {
<td>@value</td>
}
</tr>
</table>