Bottom to top text in column of Prawn table

Question

I was trying to create a pdf file using prawn in Rails 4. I needed to have vertical text as header row for a table with large width. Because if I use horizontal row heading, the table won't fit (The contents of the tables are text with 1 or 2 characters).

I tried using rotate option for prawn-table. But that only works when I set the width enough to hold the text while it is still in horizontal direction. But then it is a waste of space when I want it in vertical. But If I reduce the width of the column header the texts break.

It seems to be a bug reported here https://github.com/prawnpdf/prawn/issues/409. And it seems this pull request solves the issue https://github.com/prawnpdf/prawn-table/pull/32.

But since I'm using prawn-rails, it is difficult to me to change the gem to use that pull request, which has not yet merged to the master.

How should I proceed to solve this problem?

Answer 1

I finally solved the issue using the PR of straydogstudio in my rails project. Here is the step by step solution of it.

First edit the Gemfile to include the prawn-table gem from straydogstudio's repo.

gem 'prawn-table', :git => 'https://github.com/straydogstudio/prawn-table.git', ref: '759a27b6'

I used ref: option for minimizing the download required for the whole repository.

Next, I used :rotate option without :valign. This is important, because when :valign is used, the text somehow get messed.

The Options I used inside the prawn table initialization block is

    cells.font_size = 6
    cells.padding = [1, 1]

    row(0).rotate = 90
    row(0).columns(3..52).rotate = 0 # every splitted column should be counted
    row(0).height = 40
    row(0).width = 15
    row(0).align = :center
    row(1).columns(0..-1).rotate = 90 # rotate the second row too!
    row(1).height = 30

The result is satisfactory. Here is an screenshot of the complex setup.

Hope this will help future visitors.