Displaying image in GSP (Grails), get link from database

grailsgsp

I'm a Grails newbie. I'm trying to show an images thumbnail for every product in a site, like this:

<a href="#"><img src="${resource(dir:"images", file: "Nikon.jpg") }"/></a>/* 1 */

The problem here is that I want to save the image link in the database, and get the link by:

${fieldValue(bean: productInstance, field: "image")}  /* 2 */

But I can't replace the /* 2 / code into the places of "Nikon.jpg" in / 1 */, it causes syntax error!

After doing some research, I see that most tutorials show how to display image that stores directly in database (for example, How to display image in grails GSP?). I'm not sure if that approach is better, but I still want to take image link from database.

I also tried to search grails tag library to find any support tag, but with no success. Can anyone give me a hint?

Best Answer

The proper syntax to avoid a syntax errors would be:

<img src="${resource(dir:'images', file:fieldValue(bean:productInstance, field:'image'))}" />

But I recommend you write your own tagLib, because it is really very simple to write one and your GSPs will look much nicer if you are going to use this code a lot. You could easily write a tag that would be called something like: <product:image product='productInstance' /> and for extra usability you could make the tagLib output the link as well.

The simplicity of writing tagLibs is really one of the best grails features in my opinion.

Related Solutions

Html – Grails: displaying created image in gsp

If you write the bytes to the output stream, you can treat the controller/action as the source of the image in your GSP. Here's a quick, untested example:

// controller action
def displayGraph = {
    def img // byte array
    //...
    response.setHeader('Content-length', img.length)
    response.contentType = 'image/png' // or the appropriate image content type
    response.outputStream << img
    response.outputStream.flush()
}

You could then access your image in the src of an <img> tag like this:

<img src="${createLink(controller: 'myController', action: 'displayGraph')}"/>

Update:

After reading your question again, this may or may not work - it looks like you might be displaying the graph as the result of a form submission. This will only work if you're storing the state on the server somewhere (instead of just getting it from the one request where the form is submitted). If you do store enough state on the server to generate the graph, then you'd have to provide some additional parameters to your controller to get the correct image, e.g. src="${g.link(controller: 'myController', action: 'displayGraph', params: ['id': 1234])}", where id is how you retrieve the graph state.

Best Answer

Related Solutions

Html – Grails: displaying created image in gsp

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