roncli.com blog: Making Textboxes Ain't Easy

Now playing: Peter Enroth - Tarmdansen (3:00)

In Cent there is going to be several places where you can type in text. Naturally, I want to have a decent GUI and give the user a textbox within which they may place their text. In VB, or anything else that's got a form designer for that matter, this is a snap. Just drag and drop a textbox onto your form and you've got yourself a nice textbox.

However, I'm not using a form designer. Instead, I'm coding every aspect of the display, which means I can't just drag and drop things. For images, buttons, and text this isn't too bad. However, the fun began when I wanted a textbox a user can edit.

Now, Crystal Space has some sort of Windowing System. I didn't look too much into it, but from what I gather it's quite complicated. So I figured I'd do my own controls. How hard can it be anyway?

Textboxes hurt. Think of all the things you take for granted. When you click inside a textbox, what actually happens? You've gotta figure out where in the textbox the user clicked. But that's not enough! You have to calculate what character is at the point the user clicked, find out if it's closer that character's left side or right side, and move the cursor there. To do this, you must know how wide each character is and exactly where on the screen it is positioned.

And what if the text is too wide for the field? AARGH!!! As you can see, this gets really ugly really quick. Thank goodness for reusable code.

In any case, so far I've got my text box properly clickable so that the cursor appears in the right place. I just have to add in the eye candy (I-beam mouse when you're over the textbox, and a flashing cursor), and the ability to actually... you know... type characters into the box.

Moving? Yes. Slowly? Definitely.

Labels: Cent, Coding, Crystal Space, Gaming

0 Comments

Post a Comment