[Solved] Want to increase font size when mouse is over UI element. But can’t get OnMouseOver() to work

I have a start button in my main menu, which is an instance of UnityEnige.UI.Text. I want to increase the font size when the user hovers her mouse over the object.

So I looked up the manual and found a function called OnMouseOver() which should do exactly this (see reference ) . I added a script (see screenshot) and I made sure that my start button is a raycast target.
The script simply does not check where the mouse is and prints nothing to the console. Does anybody know what I did wrong and how to fix it?
(I realise my printscreen uses OnMouseEnter(), but I have tried both functions.)
(I use Unity version 5.6.1f1)

Hi @Erik_van_Oosterhout,

The reason for this not working is that the UI Text object is not a GUIElement.

There are several ways you can work around this, depending on what you want to achieve would dictate really the best approach. You could;

  • use Raycasting to determine what is being hit by the ray, toggling the size of the font accordingly
  • use Event Triggers to call your own methods, you can use Enter and Exit - but there isn’t any support for Over
  • use the Event System directly to determine if the mouse pointer is over a game object

I have provided a zip file with an example using the Event Triggers approach which I am sure will meet your needs. It was created in Unity 5.6.0f3, so you may be prompted to update it using 5.6.1.

Note, in this example, I have created a separate game object to attach the script to, you could potentially just add it to the text/button object, or, perhaps include the code in another object such as a GameManager / LevelManager that type of thing.

I hope this helps.


MouseInput.zip (4.0 MB)

Thank you so much! Your explanation and the added scene were very useful. And my button works now!
:slight_smile: Thanks again! I spend a good hour yesterday being utterly confused !

1 Like

You are more than welcome, I am glad you can move forward again :slight_smile:

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