Android Open Source - EverToDo Cursor Position Calculator

From Project

Back to project page EverToDo.

License

The source code is released under:

GNU General Public License

If you think the Android project EverToDo listed in this page is inappropriate, such as containing malicious code/tools or violating the copyright, please email info at java2s dot com, thanks.

Java Source Code

/**
 *//from ww  w.j  a  v  a  2 s .  c o m
 * Todo.txt Touch/src/com/todotxt/todotxttouch/util/CursorPositionCalculator.java
 *
 * Copyright (c) 2011 Tim Barlotta
 *
 * LICENSE:
 *
 * This file is part of Todo.txt Touch, an Android app for managing your todo.txt file (http://todotxt.com).
 *
 * Todo.txt Touch is free software: you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any
 * later version.
 *
 * Todo.txt Touch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with Todo.txt Touch.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * CursorPositionCalculator
 * A simple utility class for updating the text in an EditText box. Keeps the
 * cursor position in the same position.
 *
 * @author Tim Barlotta <tim[at]barlotta[dot]net>
 * @license http://www.gnu.org/licenses/gpl.html
 * @copyright 2011 Tim Barlotta
 */
package com.todotxt.todotxttouch.util;

public final class CursorPositionCalculator {

  /**
   * Calculates the cursor position when a string changes based on the cursor
   * position prior to the change
   * 
   * @param priorCursorPosition
   *            the position of the cursor prior to the change
   * @param priorValue
   *            the prior value of the string
   * @param newValue
   *            the new value of the string
   * @return the calculated position. If priorValue is null than the
   *         calculated position will be the position just after the string.
   *         If the newValue is null than the position will be 0.
   */
  public static final int calculate(int priorCursorPosition,
      String priorValue, String newValue) {
    if (newValue == null) {
      return 0;
    }

    if (priorValue == null) {
      return newValue.length();
    }

    int pos = priorCursorPosition
        + (newValue.length() - priorValue.length());
    pos = pos < 0 ? 0 : pos;
    return pos > newValue.length() ? newValue.length() : pos;
  }
}

Java Source Code List