android中Activity实现再按一次退出

Exit exit = new Exit();

@Override

public boolean onKeyDown(int keyCode, KeyEvent event) {

if (keyCode == KeyEvent.KEYCODE_BACK) {

pressAgainExit();

return true;

}

return super.onKeyDown(keyCode, event);

}

private void pressAgainExit() {

if (exit.isExit()) {

finish();

} else {

Toast.makeText(getApplicationContext(), "再按一次退出程序",

1000).show();

exit.doExitInOneSecond();

}

}
辅助类Exit.java
package com.chen.b;

import android.os.Handler;
import android.os.HandlerThread;

public class Exit {

private boolean isExit = false;
private Runnable task = new Runnable() {
@Override
public void run() {
isExit = false;
}
};

public void doExitInOneSecond() {
isExit = true;
HandlerThread thread = new HandlerThread("doTask");
thread.start();
new Handler(thread.getLooper()).postDelayed(task, 1000);
}

public boolean isExit() {
return isExit;
}

public void setExit(boolean isExit) {
this.isExit = isExit;
}
}