fix(datetime): allow calendar navigation in readonly mode; disallow keyboard navigation when disabled (#28336)

Issue number: #28121 

---------

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issue. -->

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etc). Submit multiple pull requests if needed. -->

## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->
It is not possible to navigate between months when ion-datetime is in
readonly mode. This means that if there are multiple dates selected, the
user cannot browse to view them all.

Also, keyboard navigation is not prevented in `readonly` or `disabled`
mode where it should be.

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

When `readonly`:
- Clicking the month-year button changes the month & year in readonly
mode
- Clicking the next & prev buttons changes the month in readonly mode
- Left and right arrow keys change the month in readonly mode
- Swiping/scrolling changes the month in readonly mode
- The selected date does not change when doing any of the above
- You cannot clear the value using keyboard navigation of the clear
button in readonly mode

When `disabled`:
- You cannot navigate months via keyboard navigation of the month-year
button in disabled mode
- You cannot navigate months using keyboard navigation of the previous &
next buttons in disabled mode
- You cannot navigate months via the left and right arrow keys in
disabled mode
- The selected date does not change when doing any of the above
- You cannot clear the value using keyboard navigation of the clear
button in disabled mode

Known bug:
- It is still possible to navigate through dates in `prefers-wheel` when
`disabled`. This bug existed prior to this PR. I created FW-5408 to
track this.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

<!-- If this introduces a breaking change, please describe the impact
and migration path for existing applications below. -->


## Other information

<!-- Any other information that is important to this PR such as
screenshots of how the component looks before and after the change. -->

---------

Co-authored-by: ionitron <[email protected]>
Co-authored-by: Amanda Johnston <[email protected]>

Author: 3 people

core/src/components.d.ts

@@ -915,7 +915,7 @@ export namespace Components {
          */
         "presentation": DatetimePresentation;
         /**
-          * If `true`, the datetime appears normal but is not interactive.
+          * If `true`, the datetime appears normal but the selected date cannot be changed.
          */
         "readonly": boolean;
         /**
@@ -5595,7 +5595,7 @@ declare namespace LocalJSX {
          */
         "presentation"?: DatetimePresentation;
         /**
-          * If `true`, the datetime appears normal but is not interactive.
+          * If `true`, the datetime appears normal but the selected date cannot be changed.
          */
         "readonly"?: boolean;
         /**

core/src/components/datetime/datetime.scss

@@ -185,13 +185,37 @@ ion-picker-column-internal {
   display: none;
 }
 
-:host(.datetime-readonly),
 :host(.datetime-disabled) {
   pointer-events: none;
+
+  .calendar-days-of-week,
+  .datetime-time {
+    opacity: 0.4;
+  }
 }
 
-:host(.datetime-disabled) {
-  opacity: 0.4;
+:host(.datetime-readonly) {
+  pointer-events: none;
+
+  /**
+   * Allow user to navigate months
+   * while in readonly mode
+   */
+  .calendar-action-buttons,
+  .calendar-body,
+  .datetime-year {
+    pointer-events: initial;
+  }
+
+  /**
+   * Disabled buttons should have full opacity
+   * in readonly mode
+   */
+
+  .calendar-day[disabled]:not(.calendar-day-constrained),
+  .datetime-action-buttons ion-button[disabled] {
+    opacity: 1;
+  }
 }
 
 /**

core/src/components/datetime/datetime.tsx

@@ -172,7 +172,7 @@ export class Datetime implements ComponentInterface {
   @Prop() disabled = false;
 
   /**
-   * If `true`, the datetime appears normal but is not interactive.
+   * If `true`, the datetime appears normal but the selected date cannot be changed.
    */
   @Prop() readonly = false;
 
@@ -599,6 +599,14 @@ export class Datetime implements ComponentInterface {
   };
 
   private setActiveParts = (parts: DatetimeParts, removeDate = false) => {
+    /** if the datetime component is in readonly mode,
+     * allow browsing of the calendar without changing
+     * the set value
+     */
+    if (this.readonly) {
+      return;
+    }
+
     const { multiple, minParts, maxParts, activeParts } = this;
 
     /**
@@ -1414,7 +1422,13 @@ export class Datetime implements ComponentInterface {
    */
 
   private renderFooter() {
-    const { showDefaultButtons, showClearButton } = this;
+    const { disabled, readonly, showDefaultButtons, showClearButton } = this;
+    /**
+     * The cancel, clear, and confirm buttons
+     * should not be interactive if the datetime
+     * is disabled or readonly.
+     */
+    const isButtonDisabled = disabled || readonly;
     const hasSlottedButtons = this.el.querySelector('[slot="buttons"]') !== null;
     if (!hasSlottedButtons && !showDefaultButtons && !showClearButton) {
       return;
@@ -1444,18 +1458,33 @@ export class Datetime implements ComponentInterface {
             <slot name="buttons">
               <ion-buttons>
                 {showDefaultButtons && (
-                  <ion-button id="cancel-button" color={this.color} onClick={() => this.cancel(true)}>
+                  <ion-button
+                    id="cancel-button"
+                    color={this.color}
+                    onClick={() => this.cancel(true)}
+                    disabled={isButtonDisabled}
+                  >
                     {this.cancelText}
                   </ion-button>
                 )}
                 <div class="datetime-action-buttons-container">
                   {showClearButton && (
-                    <ion-button id="clear-button" color={this.color} onClick={() => clearButtonClick()}>
+                    <ion-button
+                      id="clear-button"
+                      color={this.color}
+                      onClick={() => clearButtonClick()}
+                      disabled={isButtonDisabled}
+                    >
                       {this.clearText}
                     </ion-button>
                   )}
                   {showDefaultButtons && (
-                    <ion-button id="confirm-button" color={this.color} onClick={() => this.confirm(true)}>
+                    <ion-button
+                      id="confirm-button"
+                      color={this.color}
+                      onClick={() => this.confirm(true)}
+                      disabled={isButtonDisabled}
+                    >
                       {this.doneText}
                     </ion-button>
                   )}
@@ -1957,11 +1986,12 @@ export class Datetime implements ComponentInterface {
    */
 
   private renderCalendarHeader(mode: Mode) {
+    const { disabled } = this;
     const expandedIcon = mode === 'ios' ? chevronDown : caretUpSharp;
     const collapsedIcon = mode === 'ios' ? chevronForward : caretDownSharp;
 
-    const prevMonthDisabled = isPrevMonthDisabled(this.workingParts, this.minParts, this.maxParts);
-    const nextMonthDisabled = isNextMonthDisabled(this.workingParts, this.maxParts);
+    const prevMonthDisabled = disabled || isPrevMonthDisabled(this.workingParts, this.minParts, this.maxParts);
+    const nextMonthDisabled = disabled || isNextMonthDisabled(this.workingParts, this.maxParts);
 
     // don't use the inheritAttributes util because it removes dir from the host, and we still need that
     const hostDir = this.el.getAttribute('dir') || undefined;
@@ -1977,6 +2007,7 @@ export class Datetime implements ComponentInterface {
               aria-label="Show year picker"
               detail={false}
               lines="none"
+              disabled={disabled}
               onClick={() => {
                 this.toggleMonthAndYearView();
                 /**
@@ -2043,23 +2074,28 @@ export class Datetime implements ComponentInterface {
     );
   }
   private renderMonth(month: number, year: number) {
+    const { disabled, readonly } = this;
+
     const yearAllowed = this.parsedYearValues === undefined || this.parsedYearValues.includes(year);
     const monthAllowed = this.parsedMonthValues === undefined || this.parsedMonthValues.includes(month);
     const isCalMonthDisabled = !yearAllowed || !monthAllowed;
-    const swipeDisabled = isMonthDisabled(
-      {
-        month,
-        year,
-        day: null,
-      },
-      {
-        // The day is not used when checking if a month is disabled.
-        // Users should be able to access the min or max month, even if the
-        // min/max date is out of bounds (e.g. min is set to Feb 15, Feb should not be disabled).
-        minParts: { ...this.minParts, day: null },
-        maxParts: { ...this.maxParts, day: null },
-      }
-    );
+    const isDatetimeDisabled = disabled || readonly;
+    const swipeDisabled =
+      disabled ||
+      isMonthDisabled(
+        {
+          month,
+          year,
+          day: null,
+        },
+        {
+          // The day is not used when checking if a month is disabled.
+          // Users should be able to access the min or max month, even if the
+          // min/max date is out of bounds (e.g. min is set to Feb 15, Feb should not be disabled).
+          minParts: { ...this.minParts, day: null },
+          maxParts: { ...this.maxParts, day: null },
+        }
+      );
     // The working month should never have swipe disabled.
     // Otherwise the CSS scroll snap will not work and the user
     // can free-scroll the calendar.
@@ -2083,7 +2119,14 @@ export class Datetime implements ComponentInterface {
             const { el, highlightedDates, isDateEnabled, multiple } = this;
             const referenceParts = { month, day, year };
             const isCalendarPadding = day === null;
-            const { isActive, isToday, ariaLabel, ariaSelected, disabled, text } = getCalendarDayState(
+            const {
+              isActive,
+              isToday,
+              ariaLabel,
+              ariaSelected,
+              disabled: isDayDisabled,
+              text,
+            } = getCalendarDayState(
               this.locale,
               referenceParts,
               this.activeParts,
@@ -2094,7 +2137,8 @@ export class Datetime implements ComponentInterface {
             );
 
             const dateIsoString = convertDataToISO(referenceParts);
-            let isCalDayDisabled = isCalMonthDisabled || disabled;
+
+            let isCalDayDisabled = isCalMonthDisabled || isDayDisabled;
 
             if (!isCalDayDisabled && isDateEnabled !== undefined) {
               try {
@@ -2113,6 +2157,15 @@ export class Datetime implements ComponentInterface {
               }
             }
 
+            /**
+             * Some days are constrained through max & min or allowed dates
+             * and also disabled because the component is readonly or disabled.
+             * These need to be displayed differently.
+             */
+            const isCalDayConstrained = isCalDayDisabled && isDatetimeDisabled;
+
+            const isButtonDisabled = isCalDayDisabled || isDatetimeDisabled;
+
             let dateStyle: DatetimeHighlightStyle | undefined = undefined;
 
             /**
@@ -2158,11 +2211,12 @@ export class Datetime implements ComponentInterface {
                   data-year={year}
                   data-index={index}
                   data-day-of-week={dayOfWeek}
-                  disabled={isCalDayDisabled}
+                  disabled={isButtonDisabled}
                   class={{
                     'calendar-day-padding': isCalendarPadding,
                     'calendar-day': true,
                     'calendar-day-active': isActive,
+                    'calendar-day-constrained': isCalDayConstrained,
                     'calendar-day-today': isToday,
                   }}
                   part={dateParts}
@@ -2237,7 +2291,7 @@ export class Datetime implements ComponentInterface {
   }
 
   private renderTimeOverlay() {
-    const { hourCycle, isTimePopoverOpen, locale } = this;
+    const { disabled, hourCycle, isTimePopoverOpen, locale } = this;
     const computedHourCycle = getHourCycle(locale, hourCycle);
     const activePart = this.getActivePartsWithFallback();
 
@@ -2251,6 +2305,7 @@ export class Datetime implements ComponentInterface {
         part={`time-button${isTimePopoverOpen ? ' active' : ''}`}
         aria-expanded="false"
         aria-haspopup="true"
+        disabled={disabled}
         onClick={async (ev) => {
           const { popoverRef } = this;
 

core/src/components/datetime/test/a11y/datetime.e2e.ts

@@ -30,3 +30,102 @@ configs({ directions: ['ltr'] }).forEach(({ title, screenshot, config }) => {
     });
   });
 });
+
+/**
+ * This behavior does not differ across
+ * modes/directions.
+ */
+configs({ modes: ['ios'], directions: ['ltr'] }).forEach(({ title, config }) => {
+  test.describe(title('datetime: a11y'), () => {
+    test('datetime should be keyboard navigable', async ({ page, browserName }) => {
+      await page.setContent(
+        `
+        <ion-datetime value="2022-02-22T16:30:00"></ion-datetime>
+    `,
+        config
+      );
+      const tabKey = browserName === 'webkit' ? 'Alt+Tab' : 'Tab';
+
+      const datetime = page.locator('ion-datetime');
+      const monthYearButton = page.locator('.calendar-month-year ion-item');
+      const prevButton = page.locator('.calendar-next-prev ion-button:nth-child(1)');
+      const nextButton = page.locator('.calendar-next-prev ion-button:nth-child(2)');
+
+      await page.keyboard.press(tabKey);
+      await expect(monthYearButton).toBeFocused();
+
+      await page.keyboard.press(tabKey);
+      await expect(prevButton).toBeFocused();
+
+      await page.keyboard.press(tabKey);
+      await expect(nextButton).toBeFocused();
+
+      // check value before & after selecting via keyboard
+      const initialValue = await datetime.evaluate((el: HTMLIonDatetimeElement) => el.value);
+      expect(initialValue).toBe('2022-02-22T16:30:00');
+
+      await page.keyboard.press(tabKey);
+      await page.waitForChanges();
+
+      await page.keyboard.press('ArrowLeft');
+      await page.waitForChanges();
+
+      await page.keyboard.press('Enter');
+
+      await page.waitForChanges();
+
+      const newValue = await datetime.evaluate((el: HTMLIonDatetimeElement) => el.value);
+      expect(newValue).not.toBe('2022-02-22T16:30:00');
+    });
+
+    test('buttons should be keyboard navigable', async ({ page }) => {
+      await page.setContent(
+        `
+
+        <ion-datetime value="2022-02-22T16:30:00" show-default-buttons="true" show-clear-button="true"></ion-datetime>
+    `,
+        config
+      );
+
+      await page.waitForSelector('.datetime-ready');
+
+      const clearButton = page.locator('#clear-button button');
+      const selectedDay = page.locator('.calendar-day-active');
+
+      await expect(selectedDay).toHaveText('22');
+
+      await clearButton.focus();
+      await page.waitForChanges();
+
+      await expect(clearButton).toBeFocused();
+      await page.keyboard.press('Enter');
+
+      await page.waitForChanges();
+
+      await expect(selectedDay).toHaveCount(0);
+    });
+
+    test('should navigate through months via right arrow key', async ({ page }) => {
+      await page.setContent(
+        `
+
+        <ion-datetime value="2022-02-28"></ion-datetime>
+    `,
+        config
+      );
+
+      await page.waitForSelector('.datetime-ready');
+      const calendarMonthYear = page.locator('ion-datetime .calendar-month-year');
+      const calendarBody = page.locator('.calendar-body');
+      await expect(calendarMonthYear).toHaveText('February 2022');
+
+      await calendarBody.focus();
+      await page.waitForChanges();
+
+      await page.keyboard.press('ArrowRight');
+      await page.waitForChanges();
+
+      await expect(calendarMonthYear).toHaveText('March 2022');
+    });
+  });
+});