1 files changed, 70 insertions, 0 deletions
diff --git a/mavigator-cockpit/src/main/scala/mavigator/dashboard/RxUtil.scala b/mavigator-cockpit/src/main/scala/mavigator/dashboard/RxUtil.scala
new file mode 100644
index 0000000..2637ddf
--- /dev/null
+++ b/mavigator-cockpit/src/main/scala/mavigator/dashboard/RxUtil.scala
@@ -0,0 +1,70 @@
+package mavigator.dashboard
+
+import scala.language.implicitConversions
+import scala.util.Failure
+import scala.util.Success
+
+import org.scalajs.dom.html
+
+import rx.Obs
+import rx.Rx
+import rx.Rx
+import rx.Var
+import rx.Var
+import scalatags.JsDom.all.Frag
+import scalatags.JsDom.all.HtmlTag
+import scalatags.JsDom.all.backgroundColor
+import scalatags.JsDom.all.bindNode
+import scalatags.JsDom.all.span
+import scalatags.JsDom.all.stringFrag
+import scalatags.JsDom.all.stringStyle
+
+package object rxutil {
+
+  /** Rx, implicitly enhanced with additional methods. */
+  implicit class RichRx(val rx: Rx[_]) extends AnyVal {
+
+    /**
+     * Builds a new Rx by applying a partial function to all values of
+     * this Rx on which the function is defined.
+     * @param initial initial value of the returned Rx
+     * @param pf the partial function which filters and maps this Rx
+     * @return a new Rx resulting from applying the given partial
+     * function pf to each value on which it is defined and collecting
+     * the result
+     */
+    def collect[B](initial: B)(pf: PartialFunction[Any, B]): Rx[B] = {
+      val result: Var[B] = Var(initial)
+      Obs(rx, skipInitial = true) {
+        if (pf.isDefinedAt(rx())) {
+          result() = pf(rx())
+        }
+      }
+      result
+    }
+
+  }
+
+  /**
+   * Copied from https://github.com/lihaoyi/workbench-example-app/blob/todomvc/src/main/scala/example/Framework.scala
+   *
+   * Sticks some Rx into a Scalatags fragment, which means hooking up an Obs
+   * to propagate changes into the DOM via the element's ID. Monkey-patches
+   * the Obs onto the element itself so we have a reference to kill it when
+   * the element leaves the DOM (e.g. it gets deleted).
+   */
+  implicit def rxMod[T <: html.Element](r: Rx[HtmlTag]): Frag = {
+    def rSafe = r.toTry match {
+      case Success(v) => v.render
+      case Failure(e) => span(e.toString, backgroundColor := "red").render
+    }
+    var last = rSafe
+    Obs(r, skipInitial = true) {
+      val newLast = rSafe
+      last.parentElement.replaceChild(newLast, last)
+      last = newLast
+    }
+    bindNode(last)
+  }
+
+}