Re: Call Client Side Javascript from Java in JSF

From:
Lew <lew@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Tue, 28 Aug 2007 20:48:36 -0400
Message-ID:
<x92dndAfxMz6X0nbnZ2dnUVZ_hisnZ2d@comcast.com>
lord.tyranus.96@gmail.com wrote:

On 28 ago, 17:49, Carl <c.gro...@gmail.com> wrote:

Ricardo R??os <ricardo.rios...@gmail.com> writes:

Hello wizards, I have a JSF application, in this application I have a
button, but in the action method for this button I need to call to the
following code:
<SCRIPT language="JavaScript">
<!-- hide from old browsers
alert('Error');
//-->
</SCRIPT>
How can I do that ? It is possible ? Thanks in advance.

This question more a javascript question than a Java/JSF question. But while
you're here I might as well suggest you try putting your javascript statement
in the buttons onClick event handler:

<input type="button" value="Click Me!" onClick="alert('WooHoo!');" />

Hope that helps,
Carl.


Thanks for your reply, but in the action method for this button I need
a server side validation code , for example:

  public String button1_action()
  {
      boolean test = false;

      test = this.getSessionBean1.validateForm(this.layoutPanel1);

      if (test)
      /* Here need to call the following code
      <SCRIPT language="JavaScript">
      <!-- hide from old browsers
        alert('Ok');
       //-->
       </SCRIPT>
       */
      else
      /* Here need to call the following code
      <SCRIPT language="JavaScript">
      <!-- hide from old browsers
        alert('Error');
       //-->
       </SCRIPT>
       */

      return null;
  }


When you increased the level of specification of your question it changed the
answer.

It sounds like you need something more AJAXish, where you have JS submit to
the server-side validation code then parse the response to decide what dialog
to pop up.

OTOH, as long as you're doing a round-trip to the server to validate anyway,
why not abandon this silly Javascript and just pop up localized error messages
on the JSP itself, a technique supported directly by JSF?
<http://java.sun.com/javaee/javaserverfaces/1.2/docs/tlddocs/h/message.html>
<http://java.sun.com/javaee/javaserverfaces/1.2/docs/tlddocs/h/messages.html>

--
Lew

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