Fixed #31170 -- Added change event trigger to dismissRelatedLookupPopup.

django/contrib/admin/static/admin/js/admin/RelatedObjectLookups.js

@@ -57,6 +57,7 @@
         } else {
             elem.value = chosenId;
         }
+        $(elem).trigger('change');
         const index = window.relatedWindows.indexOf(win);
         if (index > -1) {
             window.relatedWindows.splice(index, 1);

js_tests/admin/RelatedObjectLookups.test.js

@@ -36,3 +36,43 @@ QUnit.test('dismissRelatedLookupPopup removes window from relatedWindows array',
     window.dismissRelatedLookupPopup(mockWin, '123');
     assert.equal(window.relatedWindows.indexOf(mockWin), -1, 'Window should be removed from relatedWindows array');
 });
+
+QUnit.test('dismissRelatedLookupPopup triggers change event for single value field', function(assert) {
+    assert.timeout(1000);
+    const done = assert.async();
+    const $ = django.jQuery;
+    const testId = 'test_id';
+    const newValue = '123';
+    const mockWin = {
+        name: testId,
+        close: function() {}
+    };
+    let changeTriggered = false;
+    $('#test_id').on('change', function() {
+        changeTriggered = true;
+        assert.equal(this.value, newValue, 'Value should be updated');
+        done();
+    });
+    window.dismissRelatedLookupPopup(mockWin, newValue);
+    assert.true(changeTriggered, 'Change event should be triggered');
+});
+
+QUnit.test('dismissRelatedLookupPopup triggers change event for many-to-many field', function(assert) {
+    assert.timeout(1000);
+    const $ = django.jQuery;
+    const testId = 'many_test_id';
+    const existingValue = '1,2';
+    const newValue = '3';
+    $('#many_test_id').val(existingValue);
+    const mockWin = {
+        name: testId,
+        close: function() {}
+    };
+    let changeTriggered = false;
+    $('#many_test_id').on('change', function() {
+        changeTriggered = true;
+        assert.equal(this.value, existingValue + ',' + newValue, 'Value should be appended for many-to-many fields');
+    });
+    window.dismissRelatedLookupPopup(mockWin, newValue);
+    assert.true(changeTriggered, 'Change event should be triggered');
+});