/**
* Inserts a paragraph before or after the table containing the selection.
*
* <p>We decided to use Control/Meta+UpArrow for inserting a paragraph before a table and
* Control/Meta+DownArrow for inserting a paragraph after a table. Here's the rationale:
*
* <ul>
* <li>We can't reliably detect if the user can place the caret before of after a table. Our
* playground is the DOM tree which we fully control but in the end the browser decides how
* to render each node. The table can have previous siblings or previous nodes in the DOM
* tree but they may not be rendered at all (as it happens with HTML garbage like empty
* elements) or not rendered before/after the table (as it happens with absolute positioned
* elements). So we have to insert the paragraph each time.
* <li>We can't use the same key to insert a paragraph before and after the table because we can
* have a table with just one empty cell. So we can't rely on the Enter key.
* <li>We can't use just the navigation keys because they would insert a paragraph before/after
* the table even when the user can navigate outside of the table.
* </ul>
*
* We can replace the Ctrl with Alt. The idea is to use the Up/Down arrow keys with a modifier.
* They will work form any table cell.
*
* @param event the native event that was fired
* @param before {@code true} to insert a paragraph before the table, {@code false} to insert a
* paragraph after the table
*/
protected void navigateOutsideTableCell(Event event, boolean before) {
// Navigate only if the Control or Meta modifiers are pressed along with the Up/Down arrow keys.
if (event.getAltKey() || event.getShiftKey() || !(event.getCtrlKey() ^ event.getMetaKey())) {
return;
}
Selection selection = getTextArea().getDocument().getSelection();
if (selection.getRangeCount() == 0) {
return;
} else {
selection.collapseToStart();
}
Range range = selection.getRangeAt(0);
Node ancestor = domUtils.getFirstAncestor(range.getStartContainer(), "table");
if (ancestor == null) {
return;
}
event.xPreventDefault();
Document document = getTextArea().getDocument();
Node paragraph = document.createPElement();
paragraph.appendChild(document.createTextNode(""));
if (before) {
ancestor.getParentNode().insertBefore(paragraph, ancestor);
} else {
domUtils.insertAfter(paragraph, ancestor);
}
range.selectNodeContents(paragraph.getFirstChild());
selection.removeAllRanges();
selection.addRange(range);
}