I wrote javascript codes.
By clicking the button, the child window pops up and displays a text sent from the parent window using a postMessage function.
My code could sent a text to the child window, but there's no text displayed. The text is displayed only when I keep clicking the button. I don't want the text to disappear.
I think my code is overridden by a blank script or something, though I don't write any other codes except for below.
Do you have any solution for this?
the parent window html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Parent Window</title>
</head>
<body>
<input type="button" value="TEST_BUTTON" id="testButton">
<script>
var testButton = document.getElementById('testButton');
testButton.addEventListener('click', function(event) {
event.preventDefault();
var newWindow = window.open('./child_window.html', 'popupWindow', 'width=400,height=300');
newWindow.postMessage('this is a content from the parent window.', '*');
return false;
},false);
</script>
</body>
</html>
the child window html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Pop Up Window</title>
</head>
<body>
<h1 id="mainText"></h1>
<script type="text/javascript">
var mainText = document.getElementById('mainText');
window.addEventListener('message', function(event) {
console.log(event.data);
this.mainText.innerText = event.data;
}, false)
</script>
</body>
</html>
I ended this up using localStorage instead.