feat(modal): ability to programmatically set current sheet breakpoint (#24648)

Resolves #23917

Co-authored-by: Sean Perkins <sean@ionic.io>

angular/src/directives/overlays/modal.ts

@@ -11,7 +11,7 @@ import {
   TemplateRef,
 } from '@angular/core';
 import { ProxyCmp, proxyOutputs } from '../angular-component-lib/utils';
-import { Components } from '@ionic/core';
+import { Components, ModalBreakpointChangeEventDetail } from '@ionic/core';
 
 export declare interface IonModal extends Components.IonModal {
   /**
@@ -30,6 +30,10 @@ export declare interface IonModal extends Components.IonModal {
    * Emitted after the modal has dismissed.
    */
   ionModalDidDismiss: EventEmitter<CustomEvent>;
+  /**
+   * Emitted after the modal breakpoint has changed.
+   */
+  ionBreakpointDidChange: EventEmitter<CustomEvent<ModalBreakpointChangeEventDetail>>;
   /**
    * Emitted after the modal has presented. Shorthand for ionModalWillDismiss.
    */
@@ -68,7 +72,7 @@ export declare interface IonModal extends Components.IonModal {
     'translucent',
     'trigger',
   ],
-  methods: ['present', 'dismiss', 'onDidDismiss', 'onWillDismiss'],
+  methods: ['present', 'dismiss', 'onDidDismiss', 'onWillDismiss', 'setCurrentBreakpoint', 'getCurrentBreakpoint'],
 })
 @Component({
   selector: 'ion-modal',
@@ -119,6 +123,7 @@ export class IonModal {
       'ionModalWillPresent',
       'ionModalWillDismiss',
       'ionModalDidDismiss',
+      'ionBreakpointDidChange',
       'didPresent',
       'willPresent',
       'willDismiss',

angular/test/test-app/e2e/src/modal.spec.ts

@@ -74,5 +74,20 @@ describe('Modals: Inline', () => {
     cy.get('ion-modal').trigger('click', 20, 20);
 
     cy.get('ion-modal').children('.ion-page').should('not.exist');
-  })
+  });
+
+  describe('setting the current breakpoint', () => {
+
+    it('should emit ionBreakpointDidChange', () => {
+      cy.get('#open-modal').click();
+
+      cy.get('ion-modal').then(modal => {
+        (modal.get(0) as any).setCurrentBreakpoint(1);
+      });
+
+      cy.get('#breakpointDidChange').should('have.text', '1');
+    });
+
+  });
+
 });

angular/test/test-app/src/app/modal-inline/modal-inline.component.html

@@ -1,6 +1,13 @@
 <ion-button id="open-modal">Open Modal</ion-button>
 
-<ion-modal [animated]="false" trigger="open-modal" [breakpoints]="[0.1, 0.5, 1]" [initialBreakpoint]="0.5">
+<ul>
+  <li>
+    breakpointDidChange event count: <span id="breakpointDidChange">{{ breakpointDidChangeCounter }}</span>
+  </li>
+</ul>
+
+<ion-modal [animated]="false" trigger="open-modal" [breakpoints]="[0.1, 0.5, 1]" [initialBreakpoint]="0.5"
+  (ionBreakpointDidChange)="onBreakpointDidChange()">
   <ng-template>
     <ion-content>
       <ion-list>

angular/test/test-app/src/app/modal-inline/modal-inline.component.ts

@@ -13,9 +13,15 @@ export class ModalInlineComponent implements AfterViewInit {
 
   items: string[] = [];
 
+  breakpointDidChangeCounter = 0;
+
   ngAfterViewInit(): void {
     setTimeout(() => {
       this.items = ['A', 'B', 'C', 'D'];
     }, 1000);
   }
+
+  onBreakpointDidChange() {
+    this.breakpointDidChangeCounter++;
+  }
 }

core/api.txt

@@ -783,11 +783,14 @@ ion-modal,prop,showBackdrop,boolean,true,false,false
 ion-modal,prop,swipeToClose,boolean,false,false,false
 ion-modal,prop,trigger,string | undefined,undefined,false,false
 ion-modal,method,dismiss,dismiss(data?: any, role?: string | undefined) => Promise<boolean>
+ion-modal,method,getCurrentBreakpoint,getCurrentBreakpoint() => Promise<number | undefined>
 ion-modal,method,onDidDismiss,onDidDismiss<T = any>() => Promise<OverlayEventDetail<T>>
 ion-modal,method,onWillDismiss,onWillDismiss<T = any>() => Promise<OverlayEventDetail<T>>
 ion-modal,method,present,present() => Promise<void>
+ion-modal,method,setCurrentBreakpoint,setCurrentBreakpoint(breakpoint: number) => Promise<void>
 ion-modal,event,didDismiss,OverlayEventDetail<any>,true
 ion-modal,event,didPresent,void,true
+ion-modal,event,ionBreakpointDidChange,ModalBreakpointChangeEventDetail,true
 ion-modal,event,ionModalDidDismiss,OverlayEventDetail<any>,true
 ion-modal,event,ionModalDidPresent,void,true
 ion-modal,event,ionModalWillDismiss,OverlayEventDetail<any>,true

core/src/components.d.ts

@@ -5,7 +5,7 @@
  * It contains typing information for all components that exist in this project.
  */
 import { HTMLStencilElement, JSXBase } from "@stencil/core/internal";
-import { AccordionGroupChangeEventDetail, ActionSheetAttributes, ActionSheetButton, AlertButton, AlertInput, AnimationBuilder, AutocompleteTypes, BreadcrumbCollapsedClickEventDetail, CheckboxChangeEventDetail, Color, ComponentProps, ComponentRef, DatetimeChangeEventDetail, DomRenderFn, FooterHeightFn, FrameworkDelegate, HeaderFn, HeaderHeightFn, InputChangeEventDetail, ItemHeightFn, ItemRenderFn, ItemReorderEventDetail, LoadingAttributes, MenuChangeEventDetail, ModalAttributes, NavComponent, NavComponentWithProps, NavOptions, OverlayEventDetail, PickerAttributes, PickerButton, PickerColumn, PopoverAttributes, PopoverSize, PositionAlign, PositionReference, PositionSide, RadioGroupChangeEventDetail, RangeChangeEventDetail, RangeValue, RefresherEventDetail, RouteID, RouterDirection, RouterEventDetail, RouterOutletOptions, RouteWrite, ScrollBaseDetail, ScrollDetail, SearchbarChangeEventDetail, SegmentButtonLayout, SegmentChangeEventDetail, SelectChangeEventDetail, SelectInterface, SelectPopoverOption, Side, SpinnerTypes, StyleEventDetail, SwipeGestureHandler, TabBarChangedEventDetail, TabButtonClickEventDetail, TabButtonLayout, TextareaChangeEventDetail, TextFieldTypes, ToastButton, ToggleChangeEventDetail, TransitionDoneFn, TransitionInstruction, TriggerAction, ViewController } from "./interface";
+import { AccordionGroupChangeEventDetail, ActionSheetAttributes, ActionSheetButton, AlertButton, AlertInput, AnimationBuilder, AutocompleteTypes, BreadcrumbCollapsedClickEventDetail, CheckboxChangeEventDetail, Color, ComponentProps, ComponentRef, DatetimeChangeEventDetail, DomRenderFn, FooterHeightFn, FrameworkDelegate, HeaderFn, HeaderHeightFn, InputChangeEventDetail, ItemHeightFn, ItemRenderFn, ItemReorderEventDetail, LoadingAttributes, MenuChangeEventDetail, ModalAttributes, ModalBreakpointChangeEventDetail, NavComponent, NavComponentWithProps, NavOptions, OverlayEventDetail, PickerAttributes, PickerButton, PickerColumn, PopoverAttributes, PopoverSize, PositionAlign, PositionReference, PositionSide, RadioGroupChangeEventDetail, RangeChangeEventDetail, RangeValue, RefresherEventDetail, RouteID, RouterDirection, RouterEventDetail, RouterOutletOptions, RouteWrite, ScrollBaseDetail, ScrollDetail, SearchbarChangeEventDetail, SegmentButtonLayout, SegmentChangeEventDetail, SelectChangeEventDetail, SelectInterface, SelectPopoverOption, Side, SpinnerTypes, StyleEventDetail, SwipeGestureHandler, TabBarChangedEventDetail, TabButtonClickEventDetail, TabButtonLayout, TextareaChangeEventDetail, TextFieldTypes, ToastButton, ToggleChangeEventDetail, TransitionDoneFn, TransitionInstruction, TriggerAction, ViewController } from "./interface";
 import { IonicSafeString } from "./utils/sanitization";
 import { AlertAttributes } from "./components/alert/alert-interface";
 import { CounterFormatter } from "./components/item/item-interface";
@@ -1541,6 +1541,10 @@ export namespace Components {
           * Animation to use when the modal is presented.
          */
         "enterAnimation"?: AnimationBuilder;
+        /**
+          * Returns the current breakpoint of a sheet style modal
+         */
+        "getCurrentBreakpoint": () => Promise<number | undefined>;
         /**
           * The horizontal line that displays at the top of a sheet modal. It is `true` by default when setting the `breakpoints` and `initialBreakpoint` properties.
          */
@@ -1587,6 +1591,10 @@ export namespace Components {
           * The element that presented the modal. This is used for card presentation effects and for stacking multiple modals on top of each other. Only applies in iOS mode.
          */
         "presentingElement"?: HTMLElement;
+        /**
+          * Move a sheet style modal to a specific breakpoint. The breakpoint value must be a value defined in your `breakpoints` array.
+         */
+        "setCurrentBreakpoint": (breakpoint: number) => Promise<void>;
         /**
           * If `true`, a backdrop will be displayed behind the modal.
          */
@@ -5294,6 +5302,10 @@ declare namespace LocalJSX {
           * Emitted after the modal has presented. Shorthand for ionModalWillDismiss.
          */
         "onDidPresent"?: (event: CustomEvent<void>) => void;
+        /**
+          * Emitted after the modal breakpoint has changed.
+         */
+        "onIonBreakpointDidChange"?: (event: CustomEvent<ModalBreakpointChangeEventDetail>) => void;
         /**
           * Emitted after the modal has dismissed.
          */

core/src/components/modal/gestures/sheet.ts

@@ -5,6 +5,32 @@ import { getBackdropValueForSheet } from '../utils';
 
 import { calculateSpringStep, handleCanDismiss } from './utils';
 
+export interface MoveSheetToBreakpointOptions {
+  /**
+   * The breakpoint value to move the sheet to.
+   */
+  breakpoint: number;
+  /**
+   * The offset value between the current breakpoint and the new breakpoint.
+   *
+   * For breakpoint changes as a result of a touch gesture, this value
+   * will be calculated internally.
+   *
+   * For breakpoint changes as a result of dynamically setting the value,
+   * this value should be the difference between the new and old breakpoint.
+   * For example:
+   * - breakpoints: [0, 0.25, 0.5, 0.75, 1]
+   * - Current breakpoint value is 1.
+   * - Setting the breakpoint to 0.25.
+   * - The offset value should be 0.75 (1 - 0.25).
+   */
+  breakpointOffset: number;
+  /**
+   * `true` if the sheet can be transitioned and dismissed off the view.
+   */
+  canDismiss?: boolean;
+}
+
 export const createSheetGesture = (
   baseEl: HTMLIonModalElement,
   backdropEl: HTMLIonBackdropElement,
@@ -13,6 +39,7 @@ export const createSheetGesture = (
   backdropBreakpoint: number,
   animation: Animation,
   breakpoints: number[] = [],
+  getCurrentBreakpoint: () => number,
   onDismiss: () => void,
   onBreakpointChange: (breakpoint: number) => void
 ) => {
@@ -113,6 +140,7 @@ export const createSheetGesture = (
      * allow for scrolling on the content.
      */
     const content = (detail.event.target! as HTMLElement).closest('ion-content');
+    currentBreakpoint = getCurrentBreakpoint();
 
     if (currentBreakpoint === 1 && content) {
       return false;
@@ -206,30 +234,39 @@ export const createSheetGesture = (
       return Math.abs(b - diff) < Math.abs(a - diff) ? b : a;
     });
 
+    moveSheetToBreakpoint({
+      breakpoint: closest,
+      breakpointOffset: offset,
+      canDismiss: canDismissBlocksGesture,
+    });
+  };
+
+  const moveSheetToBreakpoint = (options: MoveSheetToBreakpointOptions) => {
+    const { breakpoint, canDismiss, breakpointOffset } = options;
     /**
      * canDismiss should only prevent snapping
      * when users are trying to dismiss. If canDismiss
      * is present but the user is trying to swipe upwards,
      * we should allow that to happen,
      */
-    const shouldPreventDismiss = canDismissBlocksGesture && closest === 0;
+    const shouldPreventDismiss = canDismiss && breakpoint === 0;
-    const snapToBreakpoint = shouldPreventDismiss ? currentBreakpoint : closest;
+    const snapToBreakpoint = shouldPreventDismiss ? currentBreakpoint : breakpoint;
 
     const shouldRemainOpen = snapToBreakpoint !== 0;
-    currentBreakpoint = 0;
 
+    currentBreakpoint = 0;
     /**
      * Update the animation so that it plays from
      * the last offset to the closest snap point.
      */
     if (wrapperAnimation && backdropAnimation) {
       wrapperAnimation.keyframes([
-        { offset: 0, transform: `translateY(${offset * 100}%)` },
+        { offset: 0, transform: `translateY(${breakpointOffset * 100}%)` },
         { offset: 1, transform: `translateY(${(1 - snapToBreakpoint) * 100}%)` }
       ]);
 
       backdropAnimation.keyframes([
-        { offset: 0, opacity: `calc(var(--backdrop-opacity) * ${getBackdropValueForSheet(1 - offset, backdropBreakpoint)})` },
+        { offset: 0, opacity: `calc(var(--backdrop-opacity) * ${getBackdropValueForSheet(1 - breakpointOffset, backdropBreakpoint)})` },
         { offset: 1, opacity: `calc(var(--backdrop-opacity) * ${getBackdropValueForSheet(snapToBreakpoint, backdropBreakpoint)})` }
       ]);
 
@@ -313,5 +350,9 @@ export const createSheetGesture = (
     onMove,
     onEnd
   });
-  return gesture;
+
+  return {
+    gesture,
+    moveSheetToBreakpoint
+  };
 };

core/src/components/modal/modal-interface.ts

@@ -34,3 +34,11 @@ export interface ModalAnimationOptions {
 }
 
 export interface ModalAttributes extends JSXBase.HTMLAttributes<HTMLElement> { }
+
+export interface ModalBreakpointChangeEventDetail {
+  breakpoint: number;
+}
+
+export interface ModalCustomEvent extends CustomEvent {
+  target: HTMLIonModalElement;
+}

core/src/components/modal/modal.tsx

@@ -3,7 +3,7 @@ import { printIonWarning } from '@utils/logging';
 
 import { config } from '../../global/config';
 import { getIonMode } from '../../global/ionic-global';
-import { Animation, AnimationBuilder, ComponentProps, ComponentRef, FrameworkDelegate, Gesture, ModalAttributes, OverlayEventDetail, OverlayInterface } from '../../interface';
+import { Animation, AnimationBuilder, ComponentProps, ComponentRef, FrameworkDelegate, Gesture, ModalAttributes, ModalBreakpointChangeEventDetail, OverlayEventDetail, OverlayInterface } from '../../interface';
 import { CoreDelegate, attachComponent, detachComponent } from '../../utils/framework-delegate';
 import { raf } from '../../utils/helpers';
 import { KEYBOARD_DID_OPEN } from '../../utils/keyboard/keyboard';
@@ -15,7 +15,7 @@ import { iosEnterAnimation } from './animations/ios.enter';
 import { iosLeaveAnimation } from './animations/ios.leave';
 import { mdEnterAnimation } from './animations/md.enter';
 import { mdLeaveAnimation } from './animations/md.leave';
-import { createSheetGesture } from './gestures/sheet';
+import { MoveSheetToBreakpointOptions, createSheetGesture } from './gestures/sheet';
 import { createSwipeToCloseGesture } from './gestures/swipe-to-close';
 
 /**
@@ -46,7 +46,9 @@ export class Modal implements ComponentInterface, OverlayInterface {
   private currentBreakpoint?: number;
   private wrapperEl?: HTMLElement;
   private backdropEl?: HTMLIonBackdropElement;
+  private sortedBreakpoints?: number[];
   private keyboardOpenCallback?: () => void;
+  private moveSheetToBreakpoint?: (options: MoveSheetToBreakpointOptions) => void;
 
   private inline = false;
   private workingDelegate?: FrameworkDelegate;
@@ -56,6 +58,7 @@ export class Modal implements ComponentInterface, OverlayInterface {
 
   // Whether or not modal is being dismissed via gesture
   private gestureAnimationDismissing = false;
+
   lastFocus?: HTMLElement;
   animation?: Animation;
 
@@ -237,6 +240,11 @@ export class Modal implements ComponentInterface, OverlayInterface {
    */
   @Event({ eventName: 'ionModalDidDismiss' }) didDismiss!: EventEmitter<OverlayEventDetail>;
 
+  /**
+   * Emitted after the modal breakpoint has changed.
+   */
+  @Event() ionBreakpointDidChange!: EventEmitter<ModalBreakpointChangeEventDetail>;
+
   /**
    * Emitted after the modal has presented.
    * Shorthand for ionModalWillDismiss.
@@ -270,6 +278,12 @@ export class Modal implements ComponentInterface, OverlayInterface {
     }
   }
 
+  breakpointsChanged(breakpoints: number[] | undefined) {
+    if (breakpoints !== undefined) {
+      this.sortedBreakpoints = breakpoints.sort((a, b) => a - b);
+    }
+  }
+
   connectedCallback() {
     prepareOverlay(this.el);
   }
@@ -282,7 +296,11 @@ export class Modal implements ComponentInterface, OverlayInterface {
      * not assign the default incrementing ID.
      */
     this.modalId = (this.el.hasAttribute('id')) ? this.el.getAttribute('id')! : `ion-modal-${this.modalIndex}`;
-    this.isSheetModal = breakpoints !== undefined && initialBreakpoint !== undefined;
+    const isSheetModal = this.isSheetModal = breakpoints !== undefined && initialBreakpoint !== undefined;
+
+    if (isSheetModal) {
+      this.currentBreakpoint = this.initialBreakpoint;
+    }
 
     if (breakpoints !== undefined && initialBreakpoint !== undefined && !breakpoints.includes(initialBreakpoint)) {
       printIonWarning('Your breakpoints array must include the initialBreakpoint value.')
@@ -301,7 +319,7 @@ export class Modal implements ComponentInterface, OverlayInterface {
     if (this.isOpen === true) {
       raf(() => this.present());
     }
-
+    this.breakpointsChanged(this.breakpoints);
     this.configureTriggerInteraction();
   }
 
@@ -508,17 +526,31 @@ export class Modal implements ComponentInterface, OverlayInterface {
 
     ani.progressStart(true, 1);
 
-    const sortedBreakpoints = (this.breakpoints?.sort((a, b) => a - b)) || [];
+    const { gesture, moveSheetToBreakpoint } = createSheetGesture(
-
-    this.gesture = createSheetGesture(
       this.el,
       this.backdropEl!,
       wrapperEl,
       initialBreakpoint,
       backdropBreakpoint,
       ani,
-      sortedBreakpoints,
+      this.sortedBreakpoints,
-      () => {
+      () => this.currentBreakpoint ?? 0,
+      () => this.sheetOnDismiss(),
+      (breakpoint: number) => {
+        if (this.currentBreakpoint !== breakpoint) {
+          this.currentBreakpoint = breakpoint;
+          this.ionBreakpointDidChange.emit({ breakpoint });
+        }
+      }
+    );
+
+    this.gesture = gesture;
+    this.moveSheetToBreakpoint = moveSheetToBreakpoint;
+
+    this.gesture.enable(true);
+  }
+
+  private sheetOnDismiss() {
     /**
      * While the gesture animation is finishing
      * it is possible for a user to tap the backdrop.
@@ -531,15 +563,11 @@ export class Modal implements ComponentInterface, OverlayInterface {
      */
     this.gestureAnimationDismissing = true;
     this.animation!.onFinish(async () => {
+      this.currentBreakpoint = 0;
+      this.ionBreakpointDidChange.emit({ breakpoint: this.currentBreakpoint });
       await this.dismiss(undefined, 'gesture');
       this.gestureAnimationDismissing = false;
     });
-      },
-      (breakpoint: number) => {
-        this.currentBreakpoint = breakpoint;
-      }
-    );
-    this.gesture.enable(true);
   }
 
   /**
@@ -623,6 +651,44 @@ export class Modal implements ComponentInterface, OverlayInterface {
     return eventMethod(this.el, 'ionModalWillDismiss');
   }
 
+  /**
+   * Move a sheet style modal to a specific breakpoint. The breakpoint value must
+   * be a value defined in your `breakpoints` array.
+   */
+  @Method()
+  async setCurrentBreakpoint(breakpoint: number): Promise<void> {
+    if (!this.isSheetModal) {
+      printIonWarning('setCurrentBreakpoint is only supported on sheet modals.');
+      return;
+    }
+    if (!this.breakpoints!.includes(breakpoint)) {
+      printIonWarning(`Attempted to set invalid breakpoint value ${breakpoint}. Please double check that the breakpoint value is part of your defined breakpoints.`);
+      return;
+    }
+
+    const { currentBreakpoint, moveSheetToBreakpoint, canDismiss, breakpoints } = this;
+
+    if (currentBreakpoint === breakpoint) {
+      return;
+    }
+
+    if (moveSheetToBreakpoint) {
+      moveSheetToBreakpoint({
+        breakpoint,
+        breakpointOffset: 1 - currentBreakpoint!,
+        canDismiss: canDismiss !== undefined && canDismiss !== true && breakpoints![0] === 0,
+      });
+    }
+  }
+
+  /**
+   * Returns the current breakpoint of a sheet style modal
+   */
+  @Method()
+  async getCurrentBreakpoint(): Promise<number | undefined> {
+    return this.currentBreakpoint;
+  }
+
   private onBackdropTap = () => {
     this.dismiss(undefined, BACKDROP);
   }

core/src/components/modal/readme.md

@@ -54,7 +54,7 @@ Developers can create a sheet modal effect similar to the drawer components avai
 
 The `breakpoints` property accepts an array which states each breakpoint that the sheet can snap to when swiped. A `breakpoints` property of `[0, 0.5, 1]` would indicate that the sheet can be swiped to show 0% of the modal, 50% of the modal, and 100% of the modal. When the modal is swiped to 0%, the modal will be automatically dismissed.
 
-The `initialBreakpoint` property is required so that the sheet modal knows which breakpoint to start at when presenting. The `initalBreakpoint` value must also exist in the `breakpoints` array. Given a `breakpoints` value of `[0, 0.5, 1]`, an `initialBreakpoint` value of `0.5` would be valid as `0.5` is in the `breakpoints` array. An `initialBreakpoint` value of `0.25` would not be valid as `0.25` does not exist in the `breakpoints` array.
+The `initialBreakpoint` property is required so that the sheet modal knows which breakpoint to start at when presenting. The `initialBreakpoint` value must also exist in the `breakpoints` array. Given a `breakpoints` value of `[0, 0.5, 1]`, an `initialBreakpoint` value of `0.5` would be valid as `0.5` is in the `breakpoints` array. An `initialBreakpoint` value of `0.25` would not be valid as `0.25` does not exist in the `breakpoints` array.
 
 The `backdropBreakpoint` property can be used to customize the point at which the `ion-backdrop` will begin to fade in. This is useful when creating interfaces that have content underneath the sheet that should remain interactive. A common use case is a sheet modal that overlays a map where the map is interactive until the sheet is fully expanded.
 
@@ -86,6 +86,8 @@ Note that setting a callback function will cause the swipe gesture to be interru
 
 ## Interfaces
 
+### ModalOptions
+
 Below you will find all of the options available to you when using the `modalController`. These options should be supplied when calling `modalController.create()`.
 
 ```typescript
@@ -107,6 +109,15 @@ interface ModalOptions {
   leaveAnimation?: AnimationBuilder;
 }
 ```
+### ModalCustomEvent
+
+While not required, this interface can be used in place of the `CustomEvent` interface for stronger typing with Ionic events emitted from this component.
+
+```typescript
+interface ModalCustomEvent extends CustomEvent {
+  target: HTMLIonModalElement;
+}
+```
 
 ## Dismissing
 
@@ -1581,9 +1592,10 @@ export default {
 ## Events
 
 | Event                    | Description                                                                | Type                                            |
-| --------------------- | -------------------------------------------------------------------------- | -------------------------------------- |
+| ------------------------ | -------------------------------------------------------------------------- | ----------------------------------------------- |
 | `didDismiss`             | Emitted after the modal has dismissed. Shorthand for ionModalDidDismiss.   | `CustomEvent<OverlayEventDetail<any>>`          |
 | `didPresent`             | Emitted after the modal has presented. Shorthand for ionModalWillDismiss.  | `CustomEvent<void>`                             |
+| `ionBreakpointDidChange` | Emitted after the modal breakpoint has changed.                            | `CustomEvent<ModalBreakpointChangeEventDetail>` |
 | `ionModalDidDismiss`     | Emitted after the modal has dismissed.                                     | `CustomEvent<OverlayEventDetail<any>>`          |
 | `ionModalDidPresent`     | Emitted after the modal has presented.                                     | `CustomEvent<void>`                             |
 | `ionModalWillDismiss`    | Emitted before the modal has dismissed.                                    | `CustomEvent<OverlayEventDetail<any>>`          |
@@ -1604,6 +1616,16 @@ Type: `Promise<boolean>`
 
 
 
+### `getCurrentBreakpoint() => Promise<number | undefined>`
+
+Returns the current breakpoint of a sheet style modal
+
+#### Returns
+
+Type: `Promise<number | undefined>`
+
+
+
 ### `onDidDismiss<T = any>() => Promise<OverlayEventDetail<T>>`
 
 Returns a promise that resolves when the modal did dismiss.
@@ -1634,6 +1656,17 @@ Type: `Promise<void>`
 
 
 
+### `setCurrentBreakpoint(breakpoint: number) => Promise<void>`
+
+Move a sheet style modal to a specific breakpoint. The breakpoint value must
+be a value defined in your `breakpoints` array.
+
+#### Returns
+
+Type: `Promise<void>`
+
+
+
 
 ## Slots
 

core/src/components/modal/test/basic/e2e.ts

@@ -1,4 +1,4 @@
-import { testModal } from '../test.utils';
+import { openModal, testModal } from '../test.utils';
 import { newE2EPage } from '@stencil/core/testing';
 
 const DIRECTORY = 'basic';
@@ -96,3 +96,31 @@ test('it should dismiss the modal when clicking the backdrop', async () => {
   await page.mouse.click(20, 20);
   await ionModalDidDismiss.next();
 })
+
+test('modal: setting the breakpoint should warn the developer', async () => {
+  const page = await newE2EPage({ url: '/src/components/modal/test/basic?ionic:_testing=true' });
+
+  const warnings = [];
+
+  page.on('console', (ev) => {
+    if (ev.type() === 'warning') {
+      warnings.push(ev.text());
+    }
+  });
+
+  const modal = await openModal(page, '#basic-modal');
+
+  await modal.callMethod('setCurrentBreakpoint', 0.5);
+
+  expect(warnings.length).toBe(1);
+  expect(warnings[0]).toBe('[Ionic Warning]: setCurrentBreakpoint is only supported on sheet modals.');
+});
+
+test('modal: getting the breakpoint should return undefined', async () => {
+  const page = await newE2EPage({ url: '/src/components/modal/test/basic?ionic:_testing=true' });
+
+  const modal = await openModal(page, '#basic-modal');
+
+  const breakpoint = await modal.callMethod('getCurrentBreakpoint');
+  expect(breakpoint).toBeUndefined();
+})

core/src/components/modal/test/sheet/e2e.ts

@@ -1,6 +1,6 @@
-import { newE2EPage } from '@stencil/core/testing';
+import { E2EElement, E2EPage, newE2EPage } from '@stencil/core/testing';
-import { testModal } from '../test.utils';
+import { openModal, testModal } from '../test.utils';
-import { getActiveElement, getActiveElementParent } from '@utils/test';
+import { getActiveElement, getActiveElementParent, dragElementBy } from '@utils/test';
 
 const DIRECTORY = 'sheet';
 
@@ -117,3 +117,95 @@ test('input should not be focusable when backdrop is active', async () => {
   const parentEl = await getActiveElement(page);
   expect(parentEl.tagName).toEqual('ION-BUTTON');
 });
+
+describe('modal: sheet: setting the breakpoint', () => {
+
+  let page: E2EPage;
+
+  beforeEach(async () => {
+    page = await newE2EPage({
+      url: '/src/components/modal/test/sheet?ionic:_testing=true'
+    });
+  });
+
+  describe('setting an invalid value', () => {
+
+    let warnings: string[];
+    let modal: E2EElement;
+
+    beforeEach(async () => {
+      warnings = [];
+      page.on('console', (ev) => {
+        if (ev.type() === 'warning') {
+          warnings.push(ev.text());
+        }
+      });
+
+      modal = await openModal(page, '#sheet-modal');
+
+      await modal.callMethod('setCurrentBreakpoint', 0.01);
+    });
+
+    it('should not change the breakpoint', async () => {
+      const breakpoint = await modal.callMethod('getCurrentBreakpoint');
+      expect(breakpoint).toBe(0.25);
+    });
+
+    it('should console a warning to developers', async () => {
+      expect(warnings.length).toBe(1);
+      expect(warnings[0]).toBe('[Ionic Warning]: Attempted to set invalid breakpoint value 0.01. Please double check that the breakpoint value is part of your defined breakpoints.');
+    });
+
+  });
+
+  describe('setting the breakpoint to a valid value', () => {
+
+    it('should update the current breakpoint', async () => {
+      const modal = await openModal(page, '#sheet-modal');
+
+      await modal.callMethod('setCurrentBreakpoint', 0.5);
+      await modal.waitForEvent('ionBreakpointDidChange');
+
+      const breakpoint = await modal.callMethod('getCurrentBreakpoint');
+      expect(breakpoint).toBe(0.5);
+    });
+
+    it('should emit ionBreakpointDidChange', async () => {
+      const modal = await openModal(page, '#sheet-modal');
+
+      const ionBreakpointDidChangeSpy = await modal.spyOnEvent('ionBreakpointDidChange');
+
+      await modal.callMethod('setCurrentBreakpoint', 0.5);
+      await modal.waitForEvent('ionBreakpointDidChange');
+
+      expect(ionBreakpointDidChangeSpy).toHaveReceivedEventTimes(1);
+    });
+
+    it('should emit ionBreakpointDidChange when breakpoint is set to 0', async () => {
+      const modal = await openModal(page, '#sheet-modal');
+
+      const ionBreakpointDidChangeSpy = await modal.spyOnEvent('ionBreakpointDidChange');
+
+      await modal.callMethod('setCurrentBreakpoint', 0);
+      await modal.waitForEvent('ionBreakpointDidChange');
+
+      expect(ionBreakpointDidChangeSpy).toHaveReceivedEventTimes(1);
+    });
+
+  });
+
+  it('should emit ionBreakpointDidChange when the sheet is swiped to breakpoint 0', async () => {
+    const modal = await openModal(page, '#sheet-modal');
+
+    const ionBreakpointDidChangeSpy = await modal.spyOnEvent('ionBreakpointDidChange');
+
+    const headerEl = await page.$('ion-modal ion-header');
+
+    await dragElementBy(headerEl, page, 0, 500);
+
+    await modal.waitForEvent('ionBreakpointDidChange');
+
+    expect(ionBreakpointDidChangeSpy).toHaveReceivedEventTimes(1);
+  });
+
+});

core/src/components/modal/test/sheet/index.html

@@ -4,7 +4,8 @@
 <head>
   <meta charset="UTF-8">
   <title>Modal - Sheet</title>
-  <meta name="viewport" content="viewport-fit=cover, width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no">
+  <meta name="viewport"
+    content="viewport-fit=cover, width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no">
   <link href="../../../../../css/ionic.bundle.css" rel="stylesheet">
   <link href="../../../../../scripts/testing/styles.css" rel="stylesheet">
   <script src="../../../../../scripts/testing/scripts.js"></script>
@@ -70,7 +71,6 @@
     .grid-item {
       height: 200px;
     }
-
   </style>
 </head>
 
@@ -91,15 +91,30 @@
         </ion-item>
 
         <ion-button id="sheet-modal" onclick="presentModal()">Present Sheet Modal</ion-button>
-        <ion-button id="custom-breakpoint-modal" onclick="presentModal({ initialBreakpoint: 0.5, breakpoints: [0, 0.5, 1] })">Present Sheet Modal (Custom Breakpoints)</ion-button>
+        <ion-button id="custom-breakpoint-modal"
-        <ion-button id="custom-breakpoint-modal" onclick="presentModal({ initialBreakpoint: 0.5, breakpoints: [0, 0.5, 0.75] })">Present Sheet Modal (Max breakpoint is not 1)</ion-button>
+          onclick="presentModal({ initialBreakpoint: 0.5, breakpoints: [0, 0.5, 1] })">Present Sheet Modal (Custom
-        <ion-button id="custom-backdrop-modal" onclick="presentModal({ backdropBreakpoint: 0.5, initialBreakpoint: 0.5 })">Present Sheet Modal (Custom Backdrop Breakpoint)</ion-button>
+          Breakpoints)</ion-button>
-        <ion-button id="custom-backdrop-off-center-modal" onClick="presentModal({ backdropBreakpoint: 0.3, initialBreakpoint: 0.3, breakpoints: [0.3, 0.5, 0.7, 1] })">Present Sheet Modal (Backdrop breakpoint is off-center)</ion-button>
+        <ion-button id="custom-breakpoint-modal"
-        <ion-button id="custom-height-modal" onclick="presentModal({ cssClass: 'custom-height' })">Present Sheet Modal (Custom Height)</ion-button>
+          onclick="presentModal({ initialBreakpoint: 0.5, breakpoints: [0, 0.5, 0.75] })">Present Sheet Modal (Max
-        <ion-button id="custom-handle-modal" onclick="presentModal({ cssClass: 'custom-handle' })">Present Sheet Modal (Custom Handle)</ion-button>
+          breakpoint is not 1)</ion-button>
-        <ion-button id="no-handle-modal" onclick="presentModal({ handle: false })">Present Sheet Modal (No Handle)</ion-button>
+        <ion-button id="custom-backdrop-modal"
-        <ion-button id="backdrop-active" onclick="presentModal({ backdropBreakpoint: 0.3, initialBreakpoint: 0.5, breakpoints: [0.3, 0.5, 0.7, 1] })">Backdrop is active</ion-button>
+          onclick="presentModal({ backdropBreakpoint: 0.5, initialBreakpoint: 0.5 })">Present Sheet Modal (Custom
-        <ion-button id="backdrop-inactive" onclick="presentModal({ cssClass: 'backdrop-inactive', backdropBreakpoint: 0.5, initialBreakpoint: 0.3, breakpoints: [0.3, 0.5, 0.7, 1] })">Backdrop is inactive</ion-button>
+          Backdrop Breakpoint)</ion-button>
+        <ion-button id="custom-backdrop-off-center-modal"
+          onClick="presentModal({ backdropBreakpoint: 0.3, initialBreakpoint: 0.3, breakpoints: [0.3, 0.5, 0.7, 1] })">
+          Present Sheet Modal (Backdrop breakpoint is off-center)</ion-button>
+        <ion-button id="custom-height-modal" onclick="presentModal({ cssClass: 'custom-height' })">Present Sheet Modal
+          (Custom Height)</ion-button>
+        <ion-button id="custom-handle-modal" onclick="presentModal({ cssClass: 'custom-handle' })">Present Sheet Modal
+          (Custom Handle)</ion-button>
+        <ion-button id="no-handle-modal" onclick="presentModal({ handle: false })">Present Sheet Modal (No Handle)
+        </ion-button>
+        <ion-button id="backdrop-active"
+          onclick="presentModal({ backdropBreakpoint: 0.3, initialBreakpoint: 0.5, breakpoints: [0.3, 0.5, 0.7, 1] })">
+          Backdrop is active</ion-button>
+        <ion-button id="backdrop-inactive"
+          onclick="presentModal({ cssClass: 'backdrop-inactive', backdropBreakpoint: 0.5, initialBreakpoint: 0.3, breakpoints: [0.3, 0.5, 0.7, 1] })">
+          Backdrop is inactive</ion-button>
 
         <div class="grid">
           <div class="grid-item red"></div>
@@ -117,9 +132,6 @@
 
   </ion-app>
   <script>
-    window.addEventListener("ionModalDidDismiss", function (e) { console.log('DidDismiss', e) })
-    window.addEventListener("ionModalWillDismiss", function (e) { console.log('WillDismiss', e) })
-
     function createModal(options) {
       let items = '';
 

core/src/components/modal/test/test.utils.ts

@@ -1,7 +1,28 @@
-import { newE2EPage } from '@stencil/core/testing';
+import { E2EPage, newE2EPage } from '@stencil/core/testing';
 
 import { generateE2EUrl } from '@utils/test';
 
+export const openModal = async (
+  page: E2EPage,
+  selector: string
+) => {
+  const ionModalWillPresent = await page.spyOnEvent('ionModalWillPresent');
+  const ionModalDidPresent = await page.spyOnEvent('ionModalDidPresent');
+
+  await page.click(selector);
+
+  await ionModalWillPresent.next();
+  await ionModalDidPresent.next();
+
+  await page.waitForSelector(selector);
+
+  const modal = await page.find('ion-modal');
+  await modal.waitForVisible();
+  await page.waitForTimeout(100);
+
+  return modal;
+}
+
 export const testModal = async (
   type: string,
   selector: string,
@@ -15,21 +36,10 @@ export const testModal = async (
   });
 
   const screenshotCompares = [];
-  const ionModalWillPresent = await page.spyOnEvent('ionModalWillPresent');
-  const ionModalDidPresent = await page.spyOnEvent('ionModalDidPresent');
   const ionModalWillDismiss = await page.spyOnEvent('ionModalWillDismiss');
   const ionModalDidDismiss = await page.spyOnEvent('ionModalDidDismiss');
 
-  await page.click(selector);
+  let modal = await openModal(page, selector);
-
-  await ionModalWillPresent.next();
-  await ionModalDidPresent.next();
-
-  await page.waitForSelector(selector);
-
-  let modal = await page.find('ion-modal');
-  await modal.waitForVisible();
-  await page.waitForTimeout(100);
 
   screenshotCompares.push(await page.compareScreenshot());
 

core/src/utils/test/utils.ts

@@ -83,7 +83,7 @@ export const listenForEvent = async (page: any, eventType: string, element: any,
  * element.
  */
 export const dragElementBy = async (
-  element: any,
+  element: ElementHandle<Element>,
   page: any,
   x = 0,
   y = 0,