开发者

Setting caret position in JTextArea

开发者 https://www.devze.com 2023-03-05 07:40 出处:网络
I have a JTextArea. I have a function that selects some amount of text when some combination is called. It\'s done properly. The thing is, I want to move caret to the selection beginning when some tex

I have a JTextArea. I have a function that selects some amount of text when some combination is called. It's done properly. The thing is, I want to move caret to the selection beginning when some text is selected and VK_LEFT is pressed. KeyListener is implemented properly, I tested it in other way. The thing is, that when I write following code:

@Override public void keyPressed( KeyEvent e) {
        if(e.getKeyChar()==KeyEvent.VK_LEFT)
            if(mainarea.getSelectedText()!=null)
                mainarea.setCaretPosition(mainarea.getSelectionStart());
    }

and add an instance of this listener to mainarea, selec开发者_JS百科t some text (using my function) and press left arrow key, the caret position is set to the end of selection... And I wont it to be in the beginning... What's the matter? :S


Here's a code snippet

    Action moveToSelectionStart = new AbstractAction("moveCaret") {

        @Override
        public void actionPerformed(ActionEvent e) {
            int selectionStart = textComponent.getSelectionStart();
            int selectionEnd = textComponent.getSelectionEnd();
            if (selectionStart != selectionEnd) {
                textComponent.setCaretPosition(selectionEnd);
                textComponent.moveCaretPosition(selectionStart);
            }
        }

        public boolean isEnabled() {
            return textComponent.getSelectedText() != null;
        }
    };
    Object actionMapKey = "caret-to-start";
    textComponent.getInputMap().put(KeyStroke.getKeyStroke("LEFT"), actionMapKey);
    textComponent.getActionMap().put(actionMapKey, moveToSelectionStart);

Note: it's not recommended to re-define typically installed keybindings like f.i. any of the arrow keys, users might get really annoyed ;-) Better look for some that's not already bound.

0

精彩评论

暂无评论...
验证码 换一张
取 消

关注公众号