Survey and Page Title and Description placeholders are not translated properly when switching creator.locale at runtime fix #6695 (#6705)

Author: andrewtelnov

packages/survey-creator-core/src/components/string-editor.ts

@@ -256,8 +256,11 @@ export class StringEditorViewModelBase extends Base {
     super();
     this.locString = locString;
     this.checkMarkdownToTextConversion(this.locString.owner, this.locString.name);
+    this.creator?.onLocaleChanded.add(this.onLocaleChanged);
   }
-
+  private onLocaleChanged = () => {
+    this.resetPropertyValue("placeholderValue");
+  };
   public afterRender() {
     if (this.connector.focusOnEditor) {
       if (this.activate()) this.connector.focusOnEditor = false;
@@ -271,6 +274,7 @@ export class StringEditorViewModelBase extends Base {
   }
 
   public dispose(): void {
+    this.creator?.onLocaleChanded.remove(this.onLocaleChanged);
     super.dispose();
     this.detachFromUI();
   }

packages/survey-creator-core/tests/tabs/designer.test.ts

@@ -137,6 +137,28 @@ test("StringEditorViewModelBase page title placeholder for started page", () =>
   expect(editor.placeholder).toBe("Page 1");
 });
 
+test("StringEditorViewModelBase page title placeholder and changing creator locale on the fly, Bug#6695", () => {
+  const deutschStrings: any = {
+    pe: {
+      surveyTitlePlaceholder: "Umfragetitel eingeben"
+    }
+  };
+  editorLocalization.locales["de"] = deutschStrings;
+  const creator = new CreatorTester();
+  creator.JSON = {
+    pages: [
+      { elements: [{ type: "text" }] },
+      { elements: [{ type: "text" }] }
+    ]
+  };
+  const survey = creator.survey;
+  const page1 = survey.pages[0];
+  const surveyTitleEdtor: StringEditorViewModelBase = new StringEditorViewModelBase(survey.locTitle, creator);
+  expect(surveyTitleEdtor.placeholder).toBe("Survey Title");
+  creator.locale = "de";
+  expect(surveyTitleEdtor.placeholder).toBe("Umfragetitel eingeben");
+});
+
 test("Logo css", () => {
   const creator = new CreatorTester();
   var logo = new LogoImageViewModel(creator, null);