安卓开发设置完全退出按钮

back.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
android.os.Process.killProcess(android.os.Process.myPid());
}
});