This is the purpose of "ellipsize" - truncating a portion of text to indicate additional text.
In you case, you may simply need to add something like:
android:ellipsize="end"
or you might need to go deeper:
Automatically ellipsize a string in Java
Or look at this:
android ellipsize multiline textview
The idea behind extending the class is that you can customize the behavior of the TextView when the text content exceeds the space provided. For example, you can give it the appearance the it "bleeds over" by removing padding, etc. An ellipsis is an indicator that is commonly used to explain "there's more text that you can't see" - this is how it would look:
This is really a really long...
(the 3 periods are the ellipsis - your text goes the opposite direction, but it should still work)
With a custom TextView, you could change the "..." to nothing or anything else you want (even an image, which I've done).
You could also marquee the text:
TextView Marquee not working
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