Conditionally Add a Class to an Element with Om - reactjs

In Om, is there a way to add a class to an element based on some value in the main app atom?
Take the following element, for example:
(defn some-component [app owner]
(reify
om/IRender
(render
[_]
(html
[:div {:class (when (:some-key app) "awesomeclass")} "Some text!"]))))
If I somehow toggle the value of :some-key between true and false, the class doesn't get added or removed. The value of :some-key on page load determines whether or not the class gets added.
I am using this idea to conditionally show/hide (using Twitter Bootstrap's hide class) menu options based on the value of the :access key in my app state:
[:ul.dropdown-menu {:role "menu"}
[:li {:class (when (:access app) "hide")} [:a.pointer {:on-click #(om/update! app :view :login)} "Login"]]
[:li {:class (when (:access app) "hide")} [:a.pointer {:on-click #(om/update! app :view :register)} "Register"]]
[:li {:class (when-not (:access app) "hide")} [:a.pointer {:on-click #(om/update! app :view :dashboard)} "Dashboard"]]
[:li {:class (when-not (:access app) "hide")} [:a.pointer {:on-click #(om/update! app :view :settings)} "Settings"]]
[:li [:a.pointer {:on-click #(om/update! app :view :about)} "About"]]]

This code works as expected. When I click on "Click Me!", while looking at the Elements in Developer Tools (Chrome), I see the class toggling between "awesomeclass" and disappearing:
(defonce app-state (atom {:some-key true}))
(defn main []
(om/root
(fn [app owner]
(reify
om/IRender
(render [_]
(html
[:div {:class (when (:some-key app) "awesomeclass")}
"Some text!"
[:a {:on-click #(om/transact! app :some-key not)}
"Click Me!"]]))))
app-state
{:target (. js/document (getElementById "app"))}))
As rojoca pointed out, the problem might be in the way you update app-state, consider using om/transact! and om/update!. If you keep having problems, post the code that updates the state.
Note: I'm running this in Chestnut.

You should use the keyword :className instead of :class.

Related

how to rerender reagent ui with react 18 and shadow-cljs reload?

how to rerender the whole reagent tree when we save file and shadow-cljs reloads?
react 18 has new createRoot api
and even before - if nothing changed calling render has no effect
With react v18, you need to create the root node only once. After this, you can call the .render() function from it to (re-)render your application.
Also, you need to configure a function / behavior to tell shadow-cljs what it should do on during reload.
Here is a full example, taken from here https://github.com/schnaq/cljs-reagent-template
(ns playground
(:require ["react-dom/client" :refer [createRoot]]
[goog.dom :as gdom]
[reagent.core :as r]))
(defn- main []
[:main.container.mx-auto
[:h1 "Welcome to your app"]])
;; -----------------------------------------------------------------------------
(defonce root (createRoot (gdom/getElement "app")))
(defn init
[]
(.render root (r/as-element [main])))
(defn ^:dev/after-load re-render
[]
;; The `:dev/after-load` metadata causes this function to be called
;; after shadow-cljs hot-reloads code.
;; This function is called implicitly by its annotation.
(init))
shadow-cljs is configured to call the init-function from playground/init.
;; shadow-cljs.edn
{...
:builds {:frontend {:modules {:main {:init-fn playground/init}}}}}
https://github.com/move-me-to-ipfs-shipyard/Fennec/blob/bbfb566211041dd57b419ffd95f642026bb989a8/src/Fennec/ui.cljs#L263
(:require
["react-dom/client" :as Pacha.dom.client]
[reagent.core :as Kuzco.core])
; seed.cljs
(defonce root {:dom-rootA (atom (Pacha.dom.client/createRoot
(.getElementById js/document "ui")))})
; ui.cljs
(:require [Fennec.seed :refer [root]])
(defn reload
[]
(when-let [dom-root #(:dom-rootA root)]
(.unmount dom-root)
(let [new-dom-root (Pacha.dom.client/createRoot
(.getElementById js/document "ui"))]
(reset! (:Pacha-dom-rootA root) new-dom-root)
(.render #(:Pacha-dom-rootA root)
(Kuzco.core/as-element [rc-current-page])))))

ReactTestUtils.Simulate.mouseDown

I'm trying to use the React Simulate function to simulate a mouseDown event for testing.
(defn mouse-down [node]
((.-mouseDown(.-Simulate ReactTestUtils) node (clj->js {:button 0})))
js translation:
ReactTestUtils.Simulate.mouseDown(node, {button: 0})
Nothing I've tried has resulted in an invocation of the mousedown listener--but when the listener is there when i try it in the browser where it works. It's just in the simulation.
What am I missing?
There are a couple mistakes in the Syntax here and your parens don't match. Generally it becomes easier if you reorganize the code a bit and -> can help there. As mentioned in the comment you want to use .mouseDown instead of .-mouseDown. I opted to use #js instead of clj->js since that is more optimal for static js objects such as this.
(defn mouse-down [node]
(-> (.-Simulate ReactTestUtils)
(.mouseDown node #js {:button 0})))
You can also make this a little more readable depending on where ReactTestUtils is coming from. I'm assuming its from the react-dom package which you just required.
;; in your ns
(:require ["react-dom/test-utils" :as ReactTestUtils])
;; which would allow
(defn mouse-down [node]
(ReactTestUtils/Simulate.mouseDown node #js {:button 0}))
;; or if you are on the latest CLJS version
(:require ["react-dom/test-utils$Simulate" :as sim])
;; and then
(defn mouse-down [node]
(sim/mouseDown node #js {:button 0}))

Problem with Autocomplete (Material UI + React + Reagent/ClojureScript)

I have a problem using the Material UI's Autocomplete with Reagent (ClojureScript). The element renders fine, but when I try to click on it, I get the following exceptions:
Uncaught TypeError: Cannot read property 'focus' of null
at handleClick (useAutocomplete.js:938)
at HTMLUnknownElement.callCallback (react-dom.development.js:189)
at Object.invokeGuardedCallbackImpl (react-dom.development.js:238)
at invokeGuardedCallback (react-dom.development.js:293)
at invokeGuardedCallbackAndCatchFirstError (react-dom.development.js:307)
at executeDispatch (react-dom.development.js:390)
at executeDispatchesAndReleaseTopLevel (react-dom.development.js:412)
at forEachAccumulated (react-dom.development.js:3260)
at runEventsInBatch (react-dom.development.js:3305)
at handleTopLevel (react-dom.development.js:3515)
useAutocomplete.js:322 Uncaught TypeError: Cannot read property 'removeAttribute' of null
at eval (useAutocomplete.js:322)
at eval (useEventCallback.js:26)
at eval (useAutocomplete.js:433)
at eval (useEventCallback.js:26)
at eval (useAutocomplete.js:463)
at eval (useAutocomplete.js:528)
at commitHookEffectListMount (react-dom.development.js:19765)
at commitPassiveHookEffects (react-dom.development.js:19803)
at HTMLUnknownElement.callCallback (react-dom.development.js:189)
at Object.invokeGuardedCallbackImpl (react-dom.development.js:238)
Breaking in JS debugger, I see that inputRef.current is null (which is what focus and removeAttribute are called on. (Oddly enough, the only place where inputRef is set in the file is by calling useRef(null), which is what results in inputRef.current being null.)
In my code, I define the Autocomplete field as follows:
(ns my-product-redacted.views.atoms
(:require [reagent.core :as r]
["#material-ui/lab/Autocomplete" :default Autocomplete]
;; other requires
))
(def autocomplete-field (r/adapt-react-class Autocomplete))
Then, in a React component, it is used as follows:
[a/autocomplete-field {:render-input (fn [js-params]
(let [clj-params (js->clj js-params)
params {:label label
:width width
:select select?
:Input-label-props {:shrink true}
:Select-props {:native true}}
all-params (into clj-params params)]
(js/console.log (clj->js all-params))
(r/as-element [a/text-field all-params])))
:options (when select? (cons {:value "" :label ""} options))
:get-option-label (fn [option] (or (get (js->clj option) "label") ""))
:default-value (when (not select?) value-override)
:value (when select? value)
:disabled disabled?
:on-focus #(re-frame/dispatch [::forms/on-focus path])
:on-blur #(re-frame/dispatch [::forms/on-blur path])
:on-change #(re-frame/dispatch (conj on-change (-> % .-target .-value)))})]
(Here, a/text-field is also defined in the same namespace as a/autocomplete-field and in a similar way.)
The JS console log (from the (js/console.log (clj->js params)) call) shows that inputProps.ref.current is set to null. However, InputProps.ref is not null. Even so, I tried to manually associate the same function as is passed with InputProps.ref to inputProps.ref.current, but that made no difference.
I have also tried the workaround suggested in https://github.com/mui-org/material-ui/issues/21245 (although that issue is with the Gestalt library, not with Reagent, it suggests that there may be a problem with ref forwarding). But wrapping the text-field into a div with the ref taken from InputProps.ref also made no difference.
Any suggestions?
Calling js->clj on the render-input js params breaks them.
I put a quick demo of the material UI autocomplete component in my demo repository here.
But it's mainly taken from the official reagent docs/examples here:
(defn autocomplete-example []
[:> mui/Grid
{:item true}
[:> Autocomplete {:options ["foo" "bar" "foobar"]
:style {:width 300}
;; Note that the function parameter is a JS Object!
;; Autocomplete expects the renderInput value to be function
;; returning React elements, not a component!
;; So reactify-component won't work here.
:render-input (fn [^js params]
;; Don't call js->clj because that would recursively
;; convert all JS objects (e.g. React ref objects)
;; to Cljs maps, which breaks them, even when converted back to JS.
;; Best thing is to use r/create-element and
;; pass the JS params to it.
;; If necessary, use JS interop to modify params.
(set! (.-variant params) "outlined")
(set! (.-label params) "Autocomplete")
(r/create-element mui/TextField params))}]])

How to set up Dynamic UI Routing for a simple Fulcro app

I've crawled through some of the web and video documentation for routing. But I'm failing to get Dynamic UI Routing working for a simple set of pages.
root.cljs
(ns ui.root)
;; ...
(defsc Index [this props]
{:query [:index]
:ident (fn [] [:id :index])
:route-segment ["index"]
:initial-state {}}
(h3 "Index"))
(defsc Landing [this props]
{:query [:landing]
:ident (fn [] [:id :landing])
:route-segment ["landing"]
:initial-state {}}
(h3 "Landing"))
(defsc Settings [this props]
{:query [:settings]
:ident (fn [] [:id :settings])
:route-segment ["settings"]
:initial-state {}}
(h3 "Setting"))
(dr/defrouter TopRouter [this {:keys [current-state] :as props}]
{:router-targets [Game Settings Landing Index]
:initial-state (fn [{:keys [current-state]}]
{:current-state current-state})}
(case current-state
:pending (dom/div "Loading...")
:failed (dom/div "Failed!")
(dom/div "No route selected.")))
(def ui-top-router (comp/factory TopRouter))
(defsc Root [this {:keys [router] :as props}]
{:query [{:router (comp/get-query TopRouter)}]
:ident (fn [] [:id :root])
:initial-state (fn [_]
{:top-router (comp/get-initial-state TopRouter {:current-state :pending})
:index {:id 1}
:landing {:id 1}
:settings {:id 1}})
:componentDidMount (fn [_] (log/info "Root Initial State /" (prim/get-initial-state Root {})))}
(log/info "Root Props /" this props)
(ui-top-router router {:current-state :pending}))
client.cljs
(ns client)
...
(app/mount! #app root/Root "app" {:initialize-state? true
:foo :bar})
Q: Initial load gives this output. How do we pass props into the Root component? I expect to see at least {:foo :bar}.
INFO [ui.root:81] - Root Props / [object Object] {}
INFO [ui.root:53] - TopRouter Props / {:current-state nil, :route-factory #object[cljs.core.MetaFn], :pending-path-segment nil, :route-props nil}
INFO [ui.root:77] - Root Initial State / nil
Q: If this is my initial state, is the :query and :ident right? And do they (:query + :ident) correspond to the :route-segment ? Do they need to?
{:index {:id 1}
:landing {:id 1}
:settings {:id 1}}
Q: How do we kick off the initial route? Calling this fails with the below message.
(dr/change-route app ["index"])
INFO [com.fulcrologic.fulcro.rendering.ident-optimized-render:146] - Optimized render failed. Falling back to root render.
>> UPDATE <<
I was able to get a working Fulcro Root :initial-state, and :query and :ident on child components.
On initial load, the router fails with this.
INFO [beatthemarket.ui.root:61] - TopRouter Props / {:current-state nil, :route-factory #object[cljs.core.MetaFn], :pending-path-segment nil, :route-props {:index/id 1, :index/text "Index Text"}}
core.cljs:159 ERROR [com.fulcrologic.fulcro.routing.dynamic-routing:410] - will-enter for router target beatthemarket.ui.root/Index did not return a valid ident. Instead it returned: [:index/id nil]
core.cljs:159 ERROR [com.fulcrologic.fulcro.routing.dynamic-routing:410] - will-enter for router target beatthemarket.ui.root/Index did not return a valid ident. Instead it returned: [:index/id nil]
browser.cljs:25 shadow-cljs: WebSocket connected!
browser.cljs:25 shadow-cljs: REPL session start successful
core.cljs:159 INFO [com.fulcrologic.fulcro.algorithms.indexing:104] - component beatthemarket.ui.root/Index's ident ([:index/id nil]) has a `nil` second element. This warning can be safely ignored if that is intended.
So a command like (dr/change-route app (dr/path-to root/Index)) fails with this.
react_devtools_backend.js:6 ERROR [com.fulcrologic.fulcro.routing.dynamic-routing:410] - will-enter for router target beatthemarket.ui.root/Index did not return a valid ident. Instead it returned: [:index/id nil]
These are my client.cljs and root.cljs look like this.
I think your Root initial state should be calling (comp/get-initial-state Index). You have an initial state set on Index but it's different than the initial state that Root gives.
Also, a big part of Fulcro (and React) is that you build a tree of components and a tree of data and they need to match.
The way you have it here, there's no connection between "Root" and "Index" because Root only renders (ui-top-router router). You're getting the data for Index by having a query for {:root/index (comp/get-query Index)} but you're not creating the connection between Root and Index by having Root call Index and pass in that data. You need a (ui-index index) inside Root.
And if you do that, then in that (ui-index index) call, index will take the value that you're setting with :initial-state. That's why you'll also need to update initial-state to call comp/get-initial-state so that you can get the :index/id 1 value that you're setting in the Index component's initial state.
(defsc Index [this {:index/keys [id text]}]
{:query [:index/id :index/text]
:ident [:index/id :index/id]
:route-segment ["index"]
:initial-state {:index/id 1
:index/text :param/text}}
(h3 text))
(defsc Root [this {:root/keys [router index landing game settings]}]
{:query [{:root/router (comp/get-query TopRouter)}
{:root/index (comp/get-query Index)}
{:root/landing (comp/get-query Landing)}
{:root/game (comp/get-query Game)}
{:root/settings (comp/get-query Settings)}]
:initial-state {:root/router {}
:root/index {:text "Index Text"}
:root/landing {:text "Landing Text"}
:root/game {:text "Game Text"}
:root/settings {:text "Settings Text"}}}
(when router
(dom/div (ui-top-router router))))
After all of that is addressed, here's the next thing you might be interested in.
You probably won't always want to hard-code index/id 1. You might need to fetch data from a server in order to have anything to render.
That's where :will-enter and "deferred routing" come into play. See the example below and the docs at http://book.fulcrologic.com/#_router_rendering_of_a_deferred_ui.
(defsc Person [this {:ui/keys [modified?]
:person/keys [id name]
:address/keys [city state]
:as props}]
{:query [:ui/modified? :person/id :person/name :address/city :address/state]
:ident :person/id
:route-segment ["person" :person/id]
:route-cancelled (fn [{:person/keys [id]}]
(log/info "Routing cancelled to user " id))
:allow-route-change? (fn [this {:ui/keys [modified?]}]
(when modified?
#?(:cljs (js/alert "You cannot navigate until the user is not modified!")))
(not modified?))
:will-enter (fn [app {:person/keys [id] :as route-params}]
(log/info "Will enter user with route params " route-params)
;; be sure to convert strings to int for this case
(let [id (if (string? id) (edn/read-string id) id)]
(dr/route-deferred [:person/id id]
#(df/load app [:person/id id] Person
{:post-mutation `dr/target-ready
:post-mutation-params {:target [:person/id id]}}))))}
I guess you first have to fix the Ident problem with your Index component.
Does routing work for the other components?

Issues with getting both POST and GET http parameters in appengine-magic 0.4.3/Compojure 0.6.4

I'm having some serious issues with capturing POST and GET parameters with the latest appengine-magic/compojure versions. The parameters always come up as blank, even though the request object clearly has the right stuff in it.
I've seen some stuff around the interwebs about a change in the Compojure protocol where you have to manually put in the wrappers. I've tried this (using the handler/api wrapper to avoid the stuff in handler/site wrapper that breaks GAE) but it still doesn't work.
What am I doing wrong here?
My project.clj file:
(defproject pitch-filter "1.0.0-SNAPSHOT"
:description "FIXME: write description"
:dependencies [[org.clojure/clojure "1.2.0"]
[org.clojure/clojure-contrib "1.2.0"]
[compojure "0.6.4"]
[hiccup "0.3.6"]
[jtidy "4aug2000r7-dev"]
[commons-lang "2.5"]]
:dev-dependencies [[appengine-magic "0.4.2"]
[clj-http "0.1.1"]])
My core.clj file:
(ns pitch-filter.core
(:use compojure.core
[appengine-magic.multipart-params :only [wrap-multipart-params]]
[hiccup.middleware :only (wrap-base-url)])
(:require [pitch-filter.fetch :as fetch]
[compojure.route :as route]
[compojure.handler :as handler]
[appengine-magic.core :as ae]
[appengine-magic.services.url-fetch :as url]
(defroutes pitch-filter-app-routes
(GET "/" [] "Main Page")
(GET "/form" []
(str "<form method='post' action='/post'>"
"<input type='text' name='test'>"
"<input type='submit'>"
"</form>"))
(POST "/post" {params :params}
(pr-str params))
(route/not-found "Page not found"))
(def pitch-filter-app-handler
(-> pitch-filter-app-routes
(handler/api)
(wrap-base-url)
))
(ae/def-appengine-app pitch-filter-app #'pitch-filter-app-handler)
It certainly looks like dev_appserver.sh is busted with App Engine 1.5.1. Pity, but you aren't really supposed to use it with appengine-magic. You should use the interactive REPL tools (i.e., ae/serve). They work fine.
I updated the ticket you opened on the appengine-magic project page (https://github.com/gcv/appengine-magic/issues/28).
-gcv
Turns out that this issue only happens when using the Google App Engine 1.5.1 dev_appserver.sh. It works fine with 1.4.3. I'll leave this open in case someone else finds a better solution.

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