'tgui::Textbox has not been declared'

Using the following headers, I have created a program that uses TGUI.

#include <SFML/Graphics.hpp>
#include <TGUI/TGUI.hpp>

The following code gives me the error "tgui::Textbox has not been declared," yet other widgets can be created with no problem:
tgui::Textbox::Ptr p = tgui::Textbox::create();

I've tried adding the headers below to see if that changed anything, but unsurprisingly it did not:
#include <TGUI/Widget.hpp>
#include <TGUI/Widgets/TextBox.hpp>

Anyone know how I might fix this? The main reason I downloaded TGUI was to be able to use textboxes and they seem to be the only widget that doesn't work... -_- (I am using TGUI 0.8 on CodeBlocks)

The class is called "TextBox", not "Textbox" (capital B).

Yikes, cannot believe it was such a simple mistake. Thanks so much for the help!