Alt+Tab using Java Robot

问题

I am trying to bring up the alt+tab menu with a Java Robot. When I call the alt_tab() method, I want to bring up the alt+tab menu and keep the menu up. I know this can be achieved using alt+ctrl+tab.

So far I have tried the code below, and also just alt+tab without the control key. I am not sure why it's not bringing up the menu. All it does is emulate pressing the alt key.

public void alt_tab() {
    Robot robot = new Robot();
    robot.keyPress(KeyEvent.VK_ALT);
    robot.keyPress(KeyEvent.VK_CONTROL);
    robot.keyPress(KeyEvent.VK_TAB);
    robot.delay(100);
    robot.keyRelease(KeyEvent.VK_TAB);
    robot.keyRelease(KeyEvent.VK_CONTROL);
    robot.keyRelease(KeyEvent.VK_ALT);
}

I am using Windows 8 Pro and JDK 7. Any help is appreciated!

回答1:

There is a Windows Dev Center thread where this very problem is discussed. Apparently the rules have changed in Windows 8.

Simulation of keyboard input, which can trigger responses in the Shell, are not guaranteed to work anymore, unless the application is an assistive technology application which has UiAccess privileges.

“An accessibility application can use SendInput to inject keystrokes corresponding to application launch shortcut keys that are handled by the shell. This functionality is not guaranteed to work for other types of applications.” — Send Input Function (Windows)

The following requirements have to be met:

• be signed
• be installed under %ProgramFiles% or %SystemRoot%\system32
• specify uiAccess='true' in the manifest
• run under SYSTEM or the currently logged-on user

– Google Groups

回答2:

I was able to find a workaround. I followed the instructions on this site to create a shortcut to the ALT+TAB menu, and use

Runtime.getRuntime().exec("cmd \c start " + <path\to\shortcut\>);

to launch the ALT+TAB menu without any special UIAccess privileges. Thanks to everyone for their responses.

来源：https://stackoverflow.com/questions/14549526/alttab-using-java-robot