/**
* Selects a range of text in a text component. If the new selection is outside of the previous
* viewable rectangle, then the view is centered around the new selection.
*
* @param textArea The text component whose selection is to be centered.
* @param start The start of the range to select.
* @param end The end of the range to select.
*/
private static void selectAndPossiblyCenter(JTextArea textArea, int start, int end) {
textArea.setSelectionStart(start);
textArea.setSelectionEnd(end);
Rectangle r = null;
try {
r = textArea.modelToView(start);
if (r == null) { // Not yet visible; i.e. JUnit tests
return;
}
if (end != start) {
r = r.union(textArea.modelToView(end));
}
} catch (BadLocationException ble) { // Never happens
ble.printStackTrace();
textArea.setSelectionStart(start);
textArea.setSelectionEnd(end);
return;
}
Rectangle visible = textArea.getVisibleRect();
// If the new selection is already in the view, don't scroll,
// as that is visually jarring.
if (visible.contains(r)) {
textArea.setSelectionStart(start);
textArea.setSelectionEnd(end);
return;
}
visible.x = r.x - (visible.width - r.width) / 2;
visible.y = r.y - (visible.height - r.height) / 2;
Rectangle bounds = textArea.getBounds();
Insets i = textArea.getInsets();
bounds.x = i.left;
bounds.y = i.top;
bounds.width -= i.left + i.right;
bounds.height -= i.top + i.bottom;
if (visible.x < bounds.x) {
visible.x = bounds.x;
}
if (visible.x + visible.width > bounds.x + bounds.width) {
visible.x = bounds.x + bounds.width - visible.width;
}
if (visible.y < bounds.y) {
visible.y = bounds.y;
}
if (visible.y + visible.height > bounds.y + bounds.height) {
visible.y = bounds.y + bounds.height - visible.height;
}
textArea.scrollRectToVisible(visible);
}
/**
* Selects a range of text in a text component. If the new selection is outside of the previous
* viewable rectangle, then the view is centered around the new selection.
*
* @param textArea The text component whose selection is to be centered.
* @param start The start of the range to select.
* @param end The end of the range to select.
*/
private static void selectAndPossiblyCenter(JTextArea textArea, int start, int end) {
boolean foldsExpanded = false;
if (textArea instanceof RSyntaxTextArea) {
RSyntaxTextArea rsta = (RSyntaxTextArea) textArea;
FoldManager fm = rsta.getFoldManager();
if (fm.isCodeFoldingSupportedAndEnabled()) {
foldsExpanded = fm.ensureOffsetNotInClosedFold(start);
foldsExpanded |= fm.ensureOffsetNotInClosedFold(end);
}
}
textArea.setSelectionStart(start);
textArea.setSelectionEnd(end);
Rectangle r = null;
try {
r = textArea.modelToView(start);
if (r == null) { // Not yet visible; i.e. JUnit tests
return;
}
if (end != start) {
r = r.union(textArea.modelToView(end));
}
} catch (BadLocationException ble) { // Never happens
ble.printStackTrace();
textArea.setSelectionStart(start);
textArea.setSelectionEnd(end);
return;
}
Rectangle visible = textArea.getVisibleRect();
// If the new selection is already in the view, don't scroll,
// as that is visually jarring.
if (!foldsExpanded && visible.contains(r)) {
textArea.setSelectionStart(start);
textArea.setSelectionEnd(end);
return;
}
visible.x = r.x - (visible.width - r.width) / 2;
visible.y = r.y - (visible.height - r.height) / 2;
Rectangle bounds = textArea.getBounds();
Insets i = textArea.getInsets();
bounds.x = i.left;
bounds.y = i.top;
bounds.width -= i.left + i.right;
bounds.height -= i.top + i.bottom;
if (visible.x < bounds.x) {
visible.x = bounds.x;
}
if (visible.x + visible.width > bounds.x + bounds.width) {
visible.x = bounds.x + bounds.width - visible.width;
}
if (visible.y < bounds.y) {
visible.y = bounds.y;
}
if (visible.y + visible.height > bounds.y + bounds.height) {
visible.y = bounds.y + bounds.height - visible.height;
}
textArea.scrollRectToVisible(visible);
}
private static int getTextAreaBaseline(JTextArea text, int height) {
Insets insets = text.getInsets();
FontMetrics fm = text.getFontMetrics(text.getFont());
return insets.top + fm.getAscent();
}