Method setText

app/src/processing/app/EditorTab.java:408–448

Replace the entire contents of this tab.

(String what)

   * Replace the entire contents of this tab.
   */
  public void setText(String what) {
    // Remove all highlights, since these will all end up at the start of the
    // text otherwise. Preserving them is tricky, so better just remove them.
    textarea.removeAllLineHighlights();
    // Set the caret update policy to NEVER_UPDATE while completely replacing
    // the current text. Normally, the caret tracks inserts and deletions, but
    // replacing the entire text will always make the caret end up at the end,
    // which isn't really useful. With NEVER_UPDATE, the caret will just keep
    // its absolute position (number of characters from the start), which isn't
    // always perfect, but the best we can do without making a diff of the old
    // and new text and some guesswork.
    // Note that we cannot use textarea.setText() here, since that first removes
    // text and then inserts the new text. Even with NEVER_UPDATE, the caret
    // always makes sure to stay valid, so first removing all text makes it
    // reset to 0. Also note that simply saving and restoring the caret position
    // will work, but then the scroll position might change in response to the
    // caret position.
    DefaultCaret caret = (DefaultCaret) textarea.getCaret();
    int policy = caret.getUpdatePolicy();
    caret.setUpdatePolicy(DefaultCaret.NEVER_UPDATE);
    try {
      Document doc = textarea.getDocument();
      int oldLength = doc.getLength();
      // The undo manager already seems to group the insert and remove together
      // automatically, but better be explicit about it.
      textarea.beginAtomicEdit();
      try {
        doc.insertString(oldLength, what, null);
        doc.remove(0, oldLength);
      } catch (BadLocationException e) {
        System.err.println("Unexpected failure replacing text");
      } finally {
        textarea.endAtomicEdit();
      }
    } finally {
      caret.setUpdatePolicy(policy);
    }
    // A trick to force textarea to recalculate the bracket matching rectangle.
    // In the worst case scenario, this should be ineffective.
    textarea.setLineWrap(textarea.getLineWrap());
  }

  /**
   * Is the text modified since the last save / load?