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Om application and application structure

I show the menu in Om using the component and subcomponent, for example:

(def app-state (atom {:location ""
                      :menuitems [["Pages" "/pages/"]
                                  ["Images" "/images/"]]}))

(defn menu-item-view [parent-cursor item owner]
  (reify
    om/IRender
    (render [this]
      (dom/li #js {:className (if (= (:location @app-state) (last item)) "active" "inactive")} 
        (dom/a #js 
               {:onClick (fn [_] (swap! app-state assoc :location (last @item)))} 
               (first item))))))

(defn menu-view [app owner]
  (reify
    om/IRender
    (render [this]
      (dom/li #js {:className "has-dropdown not-click"}
        (dom/a nil "Menu")
        (apply dom/ul #js {:className "dropdown"}
          (om/build-all (partial menu-item-view app) 
                        (:menuitems app)))))))

(om/root menu-view app-state
  {:target (. js/document (getElementById "menu"))})

My question is: how to update (@ app-state: location) and reinstall the menu correctly?

Update in the code above:

(swap! app-state assoc :location (last @item))

It works, but the tree does not update correctly.

I suspect that I need to use om / update! or om / transact! but they take the cursor and the only cursor that I have in the menu item is the current menu item, not the full state of the application. Therefore, I cannot access: location.

How is this handled?

I would prefer to use avio core.async and channels if possible.

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2 answers

, om/transact! om/update!.

: init-state : state. .

om/build-all , , .

:

(map #(om/build menu-item-view {:main-cursor app :menu-cursor %}) (:menuitems app))
+2

, , , - :

(def app-state (atom {:location ""
                      :menuitems [["Pages" "/pages/"]
                                  ["Images" "/images/"]]}))

(defn location []
  (om/ref-cursor (:location (om/root-cursor app-state))))

(defn menu-item-view [item owner]
  (reify
    om/IRender
    (render [this]
      (let [x (location)]
        (dom/li #js {:className (if (= x (last item)) "active" "inactive")}
                (dom/a #js
                       {:onClick (fn [_] (om/update! x (last @item)))}
                       (first item)))))))

(defn menu-view [app owner]
  (reify
    om/IRender
    (render [this]
      (dom/li #js {:className "has-dropdown not-click"}
              (dom/a nil "Menu")
              (apply dom/ul #js {:className "dropdown"}
                     (om/build-all menu-item-view (:menuitems app)))))))

(om/root menu-view app-state
  {:target (. js/document (getElementById "menu"))})

- .

+6

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