Question

I am writing a web app using HTML and Wicket.

In my HTML page, I have a small alert script and I need that the wicket will insert a value to the message of the alert. My code is:

HTML code:

<script>
   function version(){
   alert(<sub wicket:id="version">);
   } 
</script>
<img class="logo" src="images/logo.png" alt="" width="68" height="21" onclick="version()"/>

Java:

add(new Label("version","1.0.0");

But this is not working.

Answer 1

Wicket won’t process anything within <script>. But you can add a JavaScript function via a header contribution in your page class (or any other Component).

Wicket 1.5:

@Override
public void renderHead(IHeaderResponse response) {
    super.renderHead(response);
    response.renderJavaScript("function version(){alert('" + "1.0.0" + "');}", "version");
}

Wicket 6.0:

@Override
public void renderHead(IHeaderResponse response) {
    super.renderHead(response);
    response.render(JavaScriptHeaderItem.forScript("function version(){alert('" + "1.0.0" + "');}", "version"));
}

An alternative is to render a Label which outputs the function:

add(new Label("script", "function version(){alert('1.0.0');}").setEscapeModelStrings(false));

And in your markup

<script wicket:id="script" />
<img class="logo" src="images/logo.png" alt="" width="68" height="21" onclick="version()"/>