fix ts issue for JSONTableDelegate.addItem

Author: bendkt

Diff for: ex1/readme.md

@@ -34,7 +34,8 @@ JSONTableDelegate.fetchProperties = async () => {
 const _createColumn = (propertyInfo:TablePropertyInfo, table:Table) => {
 	const name = propertyInfo.key
 	const id = table.getId() + "---col-" + name
-	return Element.getElementById(id) ?? new Column(id, {
+	const column = Element.getElementById(id) as Column
+	return column ?? new Column(id, {
 		propertyKey: name,
 		header: propertyInfo.label,
 		template: new Text({

Diff for: ex1/webapp/delegate/JSONTableDelegate.ts

@@ -18,7 +18,8 @@ JSONTableDelegate.fetchProperties = async () => {
 const _createColumn = (propertyInfo:TablePropertyInfo, table:Table) => {
 	const name = propertyInfo.key
 	const id = table.getId() + "---col-" + name
-	return Element.getElementById(id) ?? new Column(id, {
+	const column = Element.getElementById(id) as Column
+	return column ?? new Column(id, {
 		propertyKey: name,
 		header: propertyInfo.label,
 		template: new Text({

Diff for: ex2/webapp/delegate/JSONTableDelegate.ts

@@ -21,7 +21,8 @@ JSONTableDelegate.fetchProperties = async () => {
 const _createColumn = (propertyInfo:TablePropertyInfo, table:Table) => {
 	const name = propertyInfo.key
 	const id = table.getId() + "---col-" + name
-	return Element.getElementById(id) ?? new Column(id, {
+	const column = Element.getElementById(id) as Column
+	return column ?? new Column(id, {
 		propertyKey: name,
 		header: propertyInfo.label,
 		template: new Text({

Diff for: ex3/webapp/delegate/JSONTableDelegate.ts

@@ -21,7 +21,8 @@ JSONTableDelegate.fetchProperties = async () => {
 const _createColumn = (propertyInfo:TablePropertyInfo, table:Table) => {
 	const name = propertyInfo.key
 	const id = table.getId() + "---col-" + name
-	return Element.getElementById(id) ?? new Column(id, {
+	const column = Element.getElementById(id) as Column
+	return column ?? new Column(id, {
 		propertyKey: name,
 		header: propertyInfo.label,
 		template: new Text({

Diff for: ex4/webapp/delegate/JSONTableDelegate.ts

@@ -23,7 +23,8 @@ JSONTableDelegate.fetchProperties = async () => {
 const _createColumn = (propertyInfo:TablePropertyInfo, table:Table) => {
 	const name = propertyInfo.key
 	const id = table.getId() + "---col-" + name
-	return Element.getElementById(id) ?? new Column(id, {
+	const column = Element.getElementById(id) as Column
+	return column ?? new Column(id, {
 		propertyKey: name,
 		header: propertyInfo.label,
 		template: new Text({

Diff for: ex5/webapp/delegate/JSONTableDelegate.ts

@@ -23,7 +23,8 @@ JSONTableDelegate.fetchProperties = async () => {
 const _createColumn = (propertyInfo:TablePropertyInfo, table:Table) => {
 	const name = propertyInfo.key
 	const id = table.getId() + "---col-" + name
-	return Element.getElementById(id) ?? new Column(id, {
+	const column = Element.getElementById(id) as Column
+	return column ?? new Column(id, {
 		propertyKey: name,
 		header: propertyInfo.label,
 		template: new Text({