driver.sendKeyEvent(AndroidKeyCode.BACK);
    driver.sendKeyEvent(AndroidKeyCode.BACKSPACE);
    driver.sendKeyEvent(AndroidKeyCode.DEL);
    driver.sendKeyEvent(AndroidKeyCode.ENTER);
    driver.sendKeyEvent(AndroidKeyCode.HOME);
    driver.sendKeyEvent(AndroidKeyCode.MENU);
    driver.sendKeyEvent(AndroidKeyCode.SETTINGS);
    driver.sendKeyEvent(AndroidKeyCode.SPACE);

更多KeyCode值参看

http://blog.csdn.net/jlminghui/article/details/39268419

Appium AndroidKeyCode