Move caret position in StyleTextArea by line number

[firm1]

Hello,

I don't know if it's handle correctly, but i can't move caret position with line number like parameter.

I would like use something like textarea.positionCaret(int row), but the only param avalaible is number of characters.

I found and tried this solution without success:

textarea.selectRange()

textarea.position(row, col)

textarea.positionCaret()

Somebody can tell me how i can do for solve my problem ?

[JordanMartinez]

There's currently no API that does what you want efficiently.

Since the caret can only be set via an actual character position, the following code will work but it's inefficient. It'd be better to implement a method specifically for this, such as StyledTextAreaModel#positionCaret(int row, int col):

Edit: Better argument checking

public void positionCaret(StyledTextArea<?, ?> area, int row, int col) {
    if (row < 0 || area.getParagraphs().size() - 1 < row) {
        throw new IllegalArgumentException("The given row is either negative or bigger than " +
                "the size of the area's paragraphs");
    }
    if (col < 0 || area.getParagraph(row).length() < col) {
        throw new IllegalArgumentException("The given column is either negative or bigger than " +
                "the length of the paragraph");
    }

    int position = 0;
    for (Paragraph par : area.getParagraphs().subList(0, row)) {
        position += par.length() + 1; // account for line terminators
    }
    // now add the column
    area.positionCaret(position + col);
}

[TomasMikula]

I agree it would be both easier and more efficient to have a direct API for that.

For now, you can still do it somewhat simpler than what was suggested:

area.positionCaret(area.position(row, 0).toOffset());

[firm1]

Thanks @TomasMikula for the workaround it's work fine for me.