There are two things here

1. highlighting (selecting) text using the mouse or keyboard
2. styling the text selected in (1) using setSelectedTextStyle

which do you want to persist?

Also when you say

However, I want to keep them persistent so that when the textarea appeared again, the text is still highlighted.

what do you mean appear again how do you make it dissappear -

1. is it on a panel that you collapse then expand?
2. are you using setVisible to hide and show the control ?
3. are you talking about ending the program and restarting?

Thanks for you quick reply.

In other words, I have a passage of texts " Processing is an open source programming language and environment for people who want to create images, animations, and interactions". I want to display it in the GTextArea with highlighted "processing". I need GTextArea, not GLabel with StyledString, so that the user can manually highlighting as well.

I set the GTextArea visible false and set it to null as well. When the user clicks onto the button to show the text-area, I initialise the control again. The reason I did that because the position of the text-area depends on the button position, but I don't know how to set location for the text-area. The position can only be set when initialisation. Am I right?

Setting the GTextArea control to visible=false hides the control so it cannot be used.

Setting the GTextArea reference to null does not delete the control, so doing that and then recreating it in a new position is a very bad idea as you end up with multiple controls even though you can't see them.

The latest version of G4P 3.1.1 has the moveTo(x,y) method which allows you to reposition a control. So setting it to invisible then use moveTo and setting visible=true should do what you want.

Your reply helps me solve one performance issue; however, it is not the solution to my highlighting question. As my previous post, forget about showing/hiding GTextArea, I still need highlighting some texts automatically when the text-area is shown.

 

I have a passage of texts " Processing  is an open source programming language and environment for people who want to create images, animations, and interactions". I want to display it in the GTextArea with highlighted "processing". I need GTextArea, not GLabel with StyledString, so that the user can manually highlighting as well.

I need GTextArea, not GLabel with StyledString, so that the user can manually highlighting as well.

Do you mean that you want different parts of the text to have different background colours (in the same way as you can have different parts of the text bold or italic) l ike this

I have a passage of texts " Processing  is an open source programming language and environment for people who want to create images, animations, and interactions". I want to display it in the GTextArea with highlighted "processing". I need GTextArea, not GLabel with StyledString, so that the user can manually highlighting as well.

OR

do you just want to persist the start and end positions of the currently slected text (text that has been selected with the mouse or keyboard)

I've done the first one, highlighting the text with a background color when some text is selected (by using setSelectedTextStyle). 

Unfortunately that is not possible with the current version of the library. If you want this feature then raise it as an issue here and I will see how it might be implemented.

Thanks quarks, I created an issue:  http://code.google.com/p/gui4processing/issues/detail?id=11&thanks=11&ts=1360588639