SAP · tsanislavgatev · Jan 26, 2024 · Jan 18, 2024 · Jan 19, 2024 · Jan 19, 2024
diff --git a/packages/main/src/DatePicker.ts b/packages/main/src/DatePicker.ts
@@ -59,6 +59,11 @@ type DatePickerChangeEventDetail = {
 	valid: boolean,
 }
 
+type ValueStateChangeEventDetail = {
+	valueState: `${ValueState}`,
+	valid: boolean,
+}
+
 type DatePickerInputEventDetail = {
 	value: string,
 	valid: boolean,
@@ -217,6 +222,31 @@ type DatePickerInputEventDetail = {
 		},
 	},
 })
+/**
+ * Fired before the value state of the component is updated internally.
+ * The event is preventable, meaning that if it's default action is
+ * prevented, the component will not update the value state.
+ *
+ * @allowPreventDefault
+ * @public
+ * @param {string} valueState The new <code>valueState</code> that will be set.
+ */
+@event<ValueStateChangeEventDetail>("value-state-change", {
+	detail: {
+		/**
+		 * @public
+		 */
+		valueState: {
+			type: String,
+		},
+		/**
+		 * @public
+		 */
+		valid: {
+			type: Boolean,
+		},
+	},
+})
 class DatePicker extends DateComponentBase implements IFormElement {
 	/**
 	 * Defines a formatted date value.
@@ -542,12 +572,15 @@ class DatePicker extends DateComponentBase implements IFormElement {
 	}
 
 	_updateValueState() {
-		const isValid = this._checkValueValidity(this.value);
+		const valid = this._checkValueValidity(this.value);
+		const previousValueState = this.valueState;
+
+		this.valueState = valid ? ValueState.None : ValueState.Error;
+
+		const eventPrevented = !this.fireEvent<ValueStateChangeEventDetail>("value-state-change", { valueState: this.valueState, valid }, true);
 
-		if (isValid && this.valueState === ValueState.Error) { // If not valid - always set Error regardless of the current value state
-			this.valueState = ValueState.None;
-		} else if (!isValid) { // However if valid, change only Error (but not the others) to None
-			this.valueState = ValueState.Error;
+		if (eventPrevented) {
+			this.valueState = previousValueState;
 		}
 	}
 

diff --git a/packages/main/test/pages/DatePicker.html b/packages/main/test/pages/DatePicker.html
@@ -29,6 +29,10 @@
 </head>
 <body class="datepicker1auto">
 	<div style='width:600px;'>
+
+		<h3> DatePicker with value-state-change event prevented </h3>
+		<ui5-date-picker id="dpVsChangePrevented" value-state="Error"></ui5-date-picker>
+
 		<div>
 			<h3> DatePicker with no format pattern & min-max dates in ISO format</h3>
 			<ui5-date-picker id="dpMinMax-dates" min-date="2019-09-01" max-date="2019-11-01"></ui5-date-picker>
@@ -199,6 +203,12 @@ <h3>DatePicker with format `yyyy` should open picker on years</h3>
 			dp11.setAttribute("value", dp11.formatValue(new Date(2018, 11, 11)));
 		});
 
+		const datePickerValueStateChangePrevented = document.getElementById("dpVsChangePrevented");
+
+		datePickerValueStateChangePrevented.addEventListener("value-state-change", function(e) {
+			e.preventDefault();
+	});
+
 	</script>
 </body>
 </html>
diff --git a/packages/main/test/pages/DatePicker_test_page.html b/packages/main/test/pages/DatePicker_test_page.html
@@ -36,6 +36,8 @@
 	<ui5-date-picker id="dp13"></ui5-date-picker>
 	<ui5-date-picker id="dp16" format-pattern="long"></ui5-date-picker>
 	<ui5-date-picker value="Invalid value" id="dp20"></ui5-date-picker>
+	<h3> DatePicker value-state-change event prevented </h3>
+	<ui5-date-picker id="dpVsChangePrevented" value-state="Error"></ui5-date-picker>
 	<ui5-button id="b1" design="Default">Set date</ui5-button>
 
 
@@ -102,6 +104,12 @@ <h3>Test accessibleName and accessibleNameRef</h3>
 		document.getElementById('b1').addEventListener("click", function(e) {
 			dp16.setAttribute("value", dp16.formatValue(new Date(2018, 11, 11)));
 		});
+
+		const datePickerValueStateChangePrevented = document.getElementById("dpVsChangePrevented");
+
+		datePickerValueStateChangePrevented.addEventListener("value-state-change", function(e) {
+			e.preventDefault();
+		});
 	</script>
 </body>
 </html>
diff --git a/packages/main/test/specs/DatePicker.spec.js b/packages/main/test/specs/DatePicker.spec.js
@@ -1330,4 +1330,18 @@ describe("Date Picker Tests", () => {
 		let displayedYear = await datepicker.getDisplayedYear(11);
 		assert.notOk(await displayedYear.hasClass("ui5-yp-item--disabled"), "Year 2025 is not disabled");
 	});
+
+	it("Value state is not changed, when value-state-change is prevented", async () => {
+		datepicker.id = "#dpVsChangePrevented";
+
+		const input = await datepicker.getInput();
+
+		const valueState = await input.getProperty("valueState");
+		await input.click();
+		await browser.keys("Jan 29, 2019");
+
+		await browser.$("#dpVsChangePrevented").shadow$("ui5-input").shadow$("input").click(); // click elsewhere to focusout
+
+		assert.strictEqual(await input.getProperty("valueState"), valueState, "value state is not changed");
+	});
 });