Example of a re-com form with re-frame's dispatch

[yayitswei]

Could you provide an example of hooking up a re-com element to re-frame's app-db?

My attempt required some unexpected hacks:

(def path [:my-form])
(def path-m (re-frame.core/path path))

(register-handler
  ::input-changed
  [debug path-m]
  (fn [db' [_ k value]]
    (assoc db' k value)))

(register-sub
 ::input
  (fn [db [_ k]]
    (reaction (get-in @db (conj path k)))))

(defn address-input []
  (let [address (subscribe [::input :address])])]
    (fn []
       [rc/input-text
       :model (or @address "")
       :on-change #(dispatch [::input-changed :address %])])))

In particular, without the (or @address ""), I get an error on the initial page load: Validation failed for argument ':model' in component 'input-text': Expected 'string | atom'. Got 'nil'

[mike-thompson-day8]

The code looks about right. Although your assoc and get-in seem to work on different paths.
No idea how (or @address "") could yield a nil. Sorry but you'll have to debug.

Side issue: if you are going to be using on-change to get character by character updates (rather than on-blur) then make sure you use dispatch-sync, not dispatch (or you stand the chance of dropping chars). See day8/re-frame#39.

[yayitswei]

Good to know about dispatch-sync.

I put together a few helper functions for wiring up form elements. The textbox model needs a dereference but the radio button doesn't.. I'll investigate more.

(defn wired-textbox [{:keys [label key]}]
  (let [model (subscribe [::input key])]
    (fn []
      [rc/v-box
       :children
       [[rc/label :label label]
        [rc/input-text
         :model (or @model "")
         :on-change #(dispatch [::input-changed key %])]]])))

(defn wired-radiogroup [{:keys [label key options]}]
  (let [model (subscribe [::input key])]
    (fn []
      [rc/v-box
       :children
       [[rc/label :label label]
        [rc/v-box
         :gap "10px"
         :children
         [(doall (for [[c label] options]
                   ^{:key c}
                   [rc/radio-button
                    :label label
                    :value c
                    :model model
                    :label-style (if (= c @model) {:font-weight "bold"})
                    :on-change #(dispatch [::input-changed key c])]))]]]])))

[wired-textbox {:label "Address" :key :address}]
[wired-radiogroup {:label "Color"
                          :key :color
                          :options [[:blue "Blue"] [:red "Red"]]}]

Btw, re-com is the best component library I've used so far. Thanks for releasing it! Hope to see more adoption and continued updates.