Flask-admin - multiple formats of same column in ModelView

Question

I am trying to modify this Flask-admin example code http://examples.flask-admin.org/forms/admin/image/ to display both the thumbnail of the image and the raw text of the file path as two separate columns. This is basically the same problem I am trying to solve on my own project. I can make it display only one of them, but not both at the same time.

The relevant class in the example source code is:

class ImageView(sqla.ModelView):
    def _list_thumbnail(view, context, model, name):
        if not model.path:
            return ''

        return Markup('<img src="%s">' % url_for('static',                                                 filename=form.thumbgen_filename(model.path)))

    column_formatters = {
        'path': _list_thumbnail
    }

My problem is that the ModelView class includes columns to display by referencing them by their name in the SQAlchemy Model (e.g. 'name' or 'path'). If I want it to have both the path and the thumbnail then I need to include column 'path' twice. However I cannot apply different formatter functions to each of the 'path' columns. So I can have two thumbnail columns or two text path columns only.

I tried to trick it by labelling the two 'path' columns differently with column_labels, but this is a dictionary object not a list so again you can't discriminate between the two.

(full source here: https://github.com/flask-admin/flask-admin/blob/master/examples/forms/app.py)

Answer 1

You are close. Define a "dummy" column in the view's column_list property, give it a nice label via the column_label property and now you can use the "dummy" column in column_formatters property.

For example:

class ImageView(sqla.ModelView):

    # Add all your visible columns here include a "dummy" column - in this instance 'raw_path'
    column_list = ('path', 'raw_path')

    # Define label for dummy column
    column_labels = {
        'raw_path': 'Full Path'     
    }

    def _list_thumbnail(view, context, model, name):
        if not model.path:
            return ''
        return Markup('<img src="%s">' % url_for('static', filename=form.thumbgen_filename(model.path)))

    def _list_raw_path(view, context, model, name):
        if not model.path:
            return ''
        return Markup('<p>{path}</p>'.format(path=model.path))


    column_formatters = {
        'path': _list_thumbnail
        'raw_path': _list_raw_path
    }