refactor(refresher): add new ios 14 pull to refresh style

core/src/components/refresher/refresher.ios.scss

@@ -30,22 +30,27 @@ ion-refresher.refresher-native {
   display: block;
 
   z-index: 1;
-  
+
   ion-spinner {
     @include margin(0, auto, 0, auto);
   }
 }
 
-.refresher-native {
-  .refresher-refreshing ion-spinner {
-    --refreshing-rotation-duration: 2s;
-    display: none;
-    animation: var(--refreshing-rotation-duration) ease-out refresher-rotate forwards;
-  }
-  .refresher-refreshing {
-    display: none;
-    animation: 250ms linear refresher-pop forwards;
-  }
+.refresher-native .refresher-refreshing ion-spinner {
+  --refreshing-rotation-duration: 2s;
+  display: none;
+  animation: var(--refreshing-rotation-duration) ease-out refresher-rotate forwards;
+}
+.refresher-native .refresher-refreshing {
+  display: none;
+  animation: 250ms linear refresher-pop forwards;
+}
+
+.refresher-native ion-spinner {
+  width: #{$refresher-ios-native-spinner-width};
+  height: #{$refresher-ios-native-spinner-height};
+
+  color: #{$refresher-ios-native-spinner-color};
 }
 
 .refresher-native.refresher-refreshing,
@@ -67,6 +72,12 @@ ion-refresher.refresher-native {
   }
 }
 
+.refresher-native.refresher-completing ion-refresher-content .refresher-refreshing-icon {
+  transform: scale(0) rotate(180deg);
+
+  transition: 300ms;
+}
+
 @keyframes refresher-pop {
   0% {
     transform: scale(1);
@@ -88,4 +99,4 @@ ion-refresher.refresher-native {
   to {
     transform: rotate(180deg);
   }
-}
+}

core/src/components/refresher/refresher.ios.vars.scss

@@ -1,7 +1,16 @@
 @import "../../themes/ionic.globals.ios";
 
 /// @prop - Color of the refresher icon
-$refresher-ios-icon-color:         $text-color !default;
+$refresher-ios-icon-color:            $text-color !default;
 
 /// @prop - Text color of the refresher content
-$refresher-ios-text-color:         $text-color !default;
+$refresher-ios-text-color:            $text-color !default;
+
+/// @prop - Color of the native refresher spinner
+$refresher-ios-native-spinner-color:  var(--ion-color-step-450, #747577) !default;
+
+/// @prop - Width of the native refresher spinner
+$refresher-ios-native-spinner-width:  32px !default;
+
+/// @prop - Height of the native refresher spinner
+$refresher-ios-native-spinner-height: 32px !default;

core/src/components/refresher/refresher.scss

@@ -112,4 +112,4 @@ ion-refresher-content .arrow-container {
   .refresher-pulling-text, .refresher-refreshing-text {
     display: none;
   }
-}
+}

core/src/components/refresher/refresher.tsx

@@ -6,7 +6,17 @@ import { getTimeGivenProgression } from '../../utils/animation/cubic-bezier';
 import { clamp, componentOnReady, getElementRoot, raf } from '../../utils/helpers';
 import { hapticImpact } from '../../utils/native/haptic';
 
-import { createPullingAnimation, createSnapBackAnimation, getRefresherAnimationType, handleScrollWhilePulling, handleScrollWhileRefreshing, setSpinnerOpacity, shouldUseNativeRefresher, transitionEndAsync, translateElement } from './refresher.utils';
+import {
+  createPullingAnimation,
+  createSnapBackAnimation,
+  getRefresherAnimationType,
+  handleScrollWhilePulling,
+  handleScrollWhileRefreshing,
+  setSpinnerOpacity,
+  shouldUseNativeRefresher,
+  transitionEndAsync,
+  translateElement
+} from './refresher.utils';
 
 @Component({
   tag: 'ion-refresher',
@@ -147,7 +157,7 @@ export class Refresher implements ComponentInterface {
     this.state = state;
 
     if (getIonMode(this) === 'ios') {
-      await translateElement(el, undefined);
+      await translateElement(el, undefined, 300);
     } else {
       await transitionEndAsync(this.el.querySelector('.refresher-refreshing-icon'), 200);
     }
@@ -190,7 +200,6 @@ export class Refresher implements ComponentInterface {
             return;
           }
 
-          writeTask(() => setSpinnerOpacity(pullingSpinner, 0));
           return;
         }
 
@@ -206,11 +215,16 @@ export class Refresher implements ComponentInterface {
           }
         }
 
-        // delay showing the next tick marks until user has pulled 30px
-        const opacity = clamp(0, Math.abs(scrollTop) / refresherHeight, 0.99);
-        const pullAmount = this.progress = clamp(0, (Math.abs(scrollTop) - 30) / MAX_PULL, 1);
-        const currentTickToShow = clamp(0, Math.floor(pullAmount * NUM_TICKS), NUM_TICKS - 1);
-        const shouldShowRefreshingSpinner = this.state === RefresherState.Refreshing || currentTickToShow === NUM_TICKS - 1;
+        /**
+         * We want to delay the start of this gesture by ~30px
+         * when initially pulling down so the refresher does not
+         * overlap with the content. But when letting go of the
+         * gesture before the refresher completes, we want the
+         * refresher tick marks to quickly fade out.
+         */
+        const offset = (this.didStart) ? 30 : 0;
+        const pullAmount = this.progress = clamp(0, (Math.abs(scrollTop) - offset) / MAX_PULL, 1);
+        const shouldShowRefreshingSpinner = this.state === RefresherState.Refreshing || pullAmount === 1;
 
         if (shouldShowRefreshingSpinner) {
           if (this.pointerDown) {
@@ -232,7 +246,7 @@ export class Refresher implements ComponentInterface {
           }
         } else {
           this.state = RefresherState.Pulling;
-          handleScrollWhilePulling(pullingSpinner, ticks, opacity, currentTickToShow);
+          handleScrollWhilePulling(ticks, NUM_TICKS, pullAmount);
         }
       });
     };

core/src/components/refresher/refresher.utils.ts

@@ -1,7 +1,7 @@
 import { writeTask } from '@stencil/core';
 
 import { createAnimation } from '../../utils/animation/animation';
-import { componentOnReady } from '../../utils/helpers';
+import { clamp, componentOnReady } from '../../utils/helpers';
 import { isPlatform } from '../../utils/platform';
 
 // MD Native Refresher
@@ -124,14 +124,26 @@ export const setSpinnerOpacity = (spinner: HTMLElement, opacity: number) => {
 };
 
 export const handleScrollWhilePulling = (
-  spinner: HTMLElement,
   ticks: NodeListOf<SVGElement>,
-  opacity: number,
-  currentTickToShow: number
+  numTicks: number,
+  pullAmount: number
 ) => {
+  const max = 1;
   writeTask(() => {
-    setSpinnerOpacity(spinner, opacity);
-    ticks.forEach((el, i) => el.style.setProperty('opacity', (i <= currentTickToShow) ? '0.99' : '0'));
+    ticks.forEach((el, i) => {
+      /**
+       * Compute the opacity of each tick
+       * mark as a percentage of the pullAmount
+       * offset by max / numTicks so
+       * the tick marks are shown staggered.
+       */
+      const min = i * (max / numTicks);
+      const range = max - min;
+      const start = pullAmount - min;
+      const progression = clamp(0, start / range, 1);
+
+      el.style.setProperty('opacity', progression.toString());
+    });
   });
 };
 
@@ -146,13 +158,13 @@ export const handleScrollWhileRefreshing = (
   });
 };
 
-export const translateElement = (el?: HTMLElement, value?: string) => {
+export const translateElement = (el?: HTMLElement, value?: string, duration = 200) => {
   if (!el) { return Promise.resolve(); }
 
-  const trans = transitionEndAsync(el, 200);
+  const trans = transitionEndAsync(el, duration);
 
   writeTask(() => {
-    el.style.setProperty('transition', '0.2s all ease-out');
+    el.style.setProperty('transition', `${duration}ms all ease-out`);
 
     if (value === undefined) {
       el.style.removeProperty('transform');