Hi @iw2lsi,
First, allow me to rewrite your code to clarify a few points:
void Screen1View::setupScreen()
{
textArea1.setWildcard(textArea1Buffer); //Just needs to be done once, if you're using the same buffer for the text area
}
void Screen1View::setMessage(char* message, int msglen)
{
Unicode::strncpy(textArea1Buffer, message, msglen);
textArea1.resizeToCurrentText();
textArea1.invalidate(); //You just invalidate once, when you're done with your operations like updating the buffer, resizing to current text. Any prior calls to invalidate() will have no effect.
}
The reason you're seeing old text as well is because your new text is shorter and now you're (most likely) seeing the tail of the old text. In this case you're not invalidating the "tail", if you get my meaning, because you resized the text area and you're telling TouchGFX to only invalidate the new, smaller rect.
Sometimes you need to avoid resizing to current text if a text is dynamically updating and has variable length. Here you should probably have a fixed width (Worst case) with an alignment that you're happy with (left or right). In this case you may end up redrawing parts of the screen that have not been updated, but you could do something clever with checking the length of the previous text and making sure you're invalidating as little as possible if this is a performance problem for you. Most likely it isn't.
Does that make sense?
Best regards,
Martin
