jtextarea | Tech Tips & Tricks

JTextArea Cell Editor Does Not Receive Focus

November 30, 2012 by blogmeister·0 Comments

If you encounter this problem, it is most likely that your JTextArea is placed within a JScrollPanel. When the cell editor gets called, the focus is received by the scrolling panel instead of your text area.

To fix this problem, you can add a MouseListener in your JTable and call the editCellAt() method as well as having a getter method in your cell editor class and calling the requestFocusInWindow() method.

That should fix the problem.

Sample code below.

jTable1.editCellAt(row, column);
celleditorclass.getTextArea().requestFocusInWindow();

1 2	jTable1.editCellAt(row, column); celleditorclass.getTextArea().requestFocusInWindow();

Get Line Count Of JTextArea Including Word Wrap Lines

March 21, 2012 by blogmeister·6 Comments

After almost a work day’s worth of searching, I was able to find a solution to my dilemna. While JTextArea has a getLineCount() method to return the number of lines, I wanted a way to also detect wrapped lines since I wanted to set my component a fixed height if the maximum height limit is reached.

This method by user Jörg in the Java forum did the trick.

public static int getLineCountAsSeen(JTextComponent txtComp) {
	Font font = txtComp.getFont();
    FontMetrics fontMetrics = txtComp.getFontMetrics(font);
    int fontHeight = fontMetrics.getHeight();
    int lineCount;
    try {
    	int height = txtComp.modelToView(txtComp.getDocument().getEndPosition().getOffset() - 1).y;
    	lineCount = height / fontHeight + 1;
    } catch (Exception e) { 
    	lineCount = 0;
    }      
    return lineCount;
}

public static int getLineCountAsSeen(JTextComponent txtComp) {

Font font = txtComp.getFont();

FontMetrics fontMetrics = txtComp.getFontMetrics(font);

int fontHeight = fontMetrics.getHeight();

int lineCount;

try {

int height = txtComp.modelToView(txtComp.getDocument().getEndPosition().getOffset() - 1).y;

lineCount = height / fontHeight + 1;

} catch (Exception e) {

lineCount = 0;

}

return lineCount;

}

Convert Mouse Position To Caret Position In A JTextComponent

January 20, 2011 by blogmeister·0 Comments

Converting a mouse position to the caret position of a JTextComponent can be done by using the JTextComponent method viewToModel(). This can be pretty useful if you need to set the caret position of the component when you do a right click of the mouse.

The component can apply to JTextArea, JEditorPane and JTextPane respectively.

Point p = mouseEvent.getPoint();
textpane.setCaretPosition(textpane.viewToModel(p));

1 2	Point p = mouseEvent.getPoint(); textpane.setCaretPosition(textpane.viewToModel(p));

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Tag: jtextarea

JTextArea Cell Editor Does Not Receive Focus

Get Line Count Of JTextArea Including Word Wrap Lines

Convert Mouse Position To Caret Position In A JTextComponent