show loading spinner for suggested content

src/renderer/component/spinner/view.jsx

@@ -1,5 +1,5 @@
 // @flow
-import * as React from 'react';
+import React, { PureComponent } from 'react';
 import classnames from 'classnames';
 import { DARK_THEME, LIGHT_THEME } from 'constants/themes';
 
@@ -8,32 +8,78 @@ type Props = {
   light?: boolean, // always a light spinner
   theme: string,
   type: ?string,
+  delayed: boolean,
 };
 
-const Spinner = (props: Props) => {
-  const { dark, light, theme, type } = props;
-
-  return (
-    <div
-      className={classnames('spinner', {
-        'spinner--dark': !light && (dark || theme === LIGHT_THEME),
-        'spinner--light': !dark && (light || theme === DARK_THEME),
-        'spinner--splash': type === 'splash',
-        'spinner--small': type === 'small',
-      })}
-    >
-      <div className="rect rect1" />
-      <div className="rect rect2" />
-      <div className="rect rect3" />
-      <div className="rect rect4" />
-      <div className="rect rect5" />
-    </div>
-  );
+type State = {
+  show: boolean,
 };
 
-Spinner.defaultProps = {
-  dark: false,
-  light: false,
-};
+class Spinner extends PureComponent<Props, State> {
+  static defaultProps = {
+    // We may want a dark/light spinner regardless of the current theme
+    dark: false,
+    light: false,
+    delayed: false,
+  };
+
+  constructor() {
+    super();
+
+    this.state = { show: false };
+    this.delayedTimeout = null;
+  }
+
+  componentDidMount() {
+    const { delayed } = this.props;
+    if (!delayed) {
+      // We can disable this because the default state is to render nothing so there won't be any content thrashing
+      // eslint-disable-next-line react/no-did-mount-set-state
+      this.setState({ show: true });
+    } else {
+      // If the delayed prop is passed in, wait some time before showing the loading indicator
+      // We don't want the spinner to just flash for a fraction of a second
+      this.delayedTimeout = setTimeout(() => {
+        // eslint-disable-next-line react/no-did-mount-set-state
+        this.setState({ show: true });
+      }, 750);
+    }
+  }
+
+  componentWillUnmount() {
+    if (this.delayedTimeout) {
+      clearTimeout(this.delayedTimeout);
+      this.delayedTimeout = null;
+    }
+  }
+
+  delayedTimeout: ?TimeoutID;
+
+  render() {
+    const { dark, light, theme, type } = this.props;
+    const { show } = this.state;
+
+    if (!show) {
+      return null;
+    }
+
+    return (
+      <div
+        className={classnames('spinner', {
+          'spinner--dark': !light && (dark || theme === LIGHT_THEME),
+          'spinner--light': !dark && (light || theme === DARK_THEME),
+          'spinner--splash': type === 'splash',
+          'spinner--small': type === 'small',
+        })}
+      >
+        <div className="rect rect1" />
+        <div className="rect rect2" />
+        <div className="rect rect3" />
+        <div className="rect rect4" />
+        <div className="rect rect5" />
+      </div>
+    );
+  }
+}
 
 export default Spinner;

src/renderer/component/subscribeSuggested/index.js

@@ -1,9 +1,10 @@
 import { connect } from 'react-redux';
-import { selectSuggestedChannels } from 'redux/selectors/subscriptions';
+import { selectSuggestedChannels, selectIsFetchingSuggested } from 'redux/selectors/subscriptions';
 import SuggestedSubscriptions from './view';
 
 const select = state => ({
   suggested: selectSuggestedChannels(state),
+  loading: selectIsFetchingSuggested(state),
 });
 
 export default connect(

src/renderer/component/subscribeSuggested/view.jsx

@@ -1,14 +1,24 @@
 // @flow
 import React, { PureComponent } from 'react';
 import CategoryList from 'component/categoryList';
+import Spinner from 'component/spinner';
 
 type Props = {
   suggested: Array<{ label: string, uri: string }>,
+  loading: boolean,
 };
 
 class SuggestedSubscriptions extends PureComponent<Props> {
   render() {
-    const { suggested } = this.props;
+    const { suggested, loading } = this.props;
+
+    if (loading) {
+      return (
+        <div className="page__empty">
+          <Spinner delayed />
+        </div>
+      );
+    }
 
     return suggested ? (
       <div className="card__content subscriptions__suggested">

src/renderer/redux/selectors/subscriptions.js

@@ -24,7 +24,10 @@ export const selectViewMode = createSelector(selectState, state => state.viewMod
 
 // Suggested subscriptions from internal apis
 export const selectSuggested = createSelector(selectState, state => state.suggested);
-export const selectLoadingSuggested = createSelector(selectState, state => state.loadingSuggested);
+export const selectIsFetchingSuggested = createSelector(
+  selectState,
+  state => state.loadingSuggested
+);
 export const selectSuggestedChannels = createSelector(
   selectSubscriptions,
   selectSuggested,