Here is the XML code:
    <inputs>
        <param name="input_dataset" label="Input dataset" type="data" format="showelab-dataset,fbk-svm-dataset"/>
        <conditional name="format_condition">

            <param name="format_options" label="Choose the type of dataset you want to split" type="select">
                <option value="fbk">".fbk-svm-dataset" Format</option>
                <option value="showelab" selected="True">".showelab-dataset" Format</option>
            </param>
            <when value="fbk">
                <param name="input_fbk_dataset_labels" label="Input dataset labels" type="data" format="fbk-labels"/>
            </when>
        </conditional>

    </inputs>
    <outputs>
        <data format="showelab-dataset" name="trainingDataset" label="Training Dataset extracted from ${input_dataset.name}">
            <filter>format_options == "showelab"</filter>
        </data>
        <data format="showelab-dataset" name="validationDataset" label="Validation Dataset extracted from ${input_dataset.name}">
            <filter>format_options == "showelab"</filter>
        </data>
        <data format="fbk-svm-dataset" name="trainingDataset" label="Training Dataset extracted from ${input_dataset.name}">
            <filter>format_options == "fbk"</filter>
        </data>
        <data format="fbk-labels" name="trainingLabels" label="Training Dataset Labels extracted from ${input_fbk_dataset_labels.name}">
            <filter>format_options == "fbk"</filter>
        </data>
        <data format="fbk-svm-dataset" name="validationDataset" label="Validation Dataset extracted from ${input_dataset.name}">
            <filter>format_options == "fbk"</filter>
        </data>
        <data format="fbk-labels" name="validationLabels" label="Validation Dataset Labels extracted from ${input_fbk_dataset_labels.name}">
            <filter>format_options == "fbk"</filter>
        </data>

    </outputs>

Basically I would like to have in the Workflow Canvas that the outputs displayed in the interface will change according to the format_options select parameter.

Thanks in advance.