Compute function matrix

index.html

<h3>Your Results</h3>

<input type="checkbox" data-bind="checked: all"> Show all

<span data-bind="foreach: results">
  <br data-bind="visible: y() == 1"/>
  <span data-bind="visible: $root.all() || correct()">
    f(<span data-bind="text:x"></span>,
    <span data-bind="text:y"></span>) =
    <span data-bind="text:f"></span>
  </span>
</span>

Matrix.java

package dew.demo.quiz;
import net.java.html.json.*;

@Model(className="UI", properties={
  @Property(name="all", type=boolean.class),
  @Property(name="results", type=Task.class, array=true)
})
class UICntrl {
  static {
    UI ui = new UI(true);
    for (int i = 1; i <= 10; i++) {
      for (int j = 1; j <= 10; j++) {
        ui.getResults().add(new Task(i, j));
      }
    }
    ui.applyBindings();
  }

  @Model(className="Task", properties={
    @Property(name="x", type=int.class),
    @Property(name="y", type=int.class)
  })
  static class TaskCntrl {
    @ComputedProperty
    static int f(int x, int y) {
      return x * y - 5 ;
    }
    @ComputedProperty
    static boolean correct(int x, int y) {
      return f(x, y) == 13;
    }
  }
}

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