Date: 2005-01-19T10:47:43 Editor: FrankZammetti Wiki: Apache Struts Wiki Page: StrutsSolutions URL: http://wiki.apache.org/struts/StrutsSolutions
no comment Change Log: ------------------------------------------------------------------------------ @@ -26,10 +26,14 @@ 4. Exposing Struts-based functions as Web Services +5. Opening a response in a new window from a Struts Action + == DISCUSSION OF PROBLEMS (What Is The Problem?) == 4. In an application I was architect and lead developer for last year, I was asked to expose certain pieces of functionality of the system as Web Services. This request was made AFTER the application was complete and deployed in production. I did not want to spend a lot of time on this (in fact, COULDN'T) and wanted to change as little code as possible, ideally none. +5. I've seen this question asked numerous times on the Struts User's mailing list, so I thought an entry somewhere on the Wiki might be a good idea. The question is usually asked something like "How can I open a new window from an Action?" It's a little vague, but it's along the lines of how can you submit a form and have the response appear in a new window. Usually it's asked within the context of doing it variably, that is, sometimes returning in a new window, sometimes not. + == DISCUSSION OF SOLUTIONS (What Is The Solution?) == 1.1. You can distinguish between inline and attachment (with a filename) in the response content-disposition header. @@ -132,5 +136,15 @@ I don't claim this is THE way to do Web Services. Far from it. What I WILL claim though is that if you have an existing application and you want to expose parts of it as Web Services, this solution can give you a very easy way to do it, with some limitations of course... First, it is Struts 1.1-only at the moment. Second, the incoming request must be "flat", that is, no nested elements are allowed (aside from children of the root element). Third, only strings are supported, so you lose the notion of true data typing that SOAP gives you. All these details, and plenty more, as well as full source, are available at the linked address above. I welcome any suggestions anyone has. Although I haven't done much on this in a while (because it met my needs as-is), I would love to continue this work if enough people find it useful. + +5. Simply put, there is no way to do this. Opening a new window is a strictly client-side activity. You have to "fake it". There's two ways to do it... + +First, you could simply target your HTML form using the target="_blank" attribute. This will result in whatever response the server sends back appearing in a new window. The down-side to this is you have to know before-hand to do this. If you want a variable solution, you have to get into scripting... You can set the target attribute's value via client-side scripting as appropiate before submitting the form. + +Second, you could have a check in all JSP's that looks for some flag in the request object. When present, the JSP inserts an onLoad Javascript event handler that opens the new window and redirects to the URL where the content can be found. + +Another possibility if you are using frames is to target all form submissions to a hidden frame. Include in all pages some Javascript that performs some checks and handles things accordingly... I use this in one system I wrote... The checks I'm speaking of are based on some flag value in the request object (just insert the value into a page-level Javascript variable)... The flag may direct the page to copy itself to the main display frame, or to a new window. The former is a very nice way to have a "Please Wait" screen while the server is processing. The later is the same basic idea, but in a new window. This also allows you to do some nice error handling things, such as simply hiding the Please Wait layer in the main frame to expose the page as it existed before the form was submitted. Nice way to debuild a page without incurring any server time. But now I'm getting off on a tangent :) + +The bottom-line here is this: There is no way to direct the browser to open the response in a new window from an Action. You either have to indicate you want this behavior when the form is submitted, or make it happen with scripting once the response is back at the browser. At least, this is true within the confines of plain old HTML... You could always pull an applet out and do something like this! = THE END = --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
