弹出dialog时，隐藏navigation bar的方法



http://stackoverflow.com/questions/23520892/unable-to-hide-navigation-bar-during-alertdialog-logindialog（方法来源）

放在自定义dialog中即可

@Override
public void onStart() {
super.onStart();
Window window = this.getWindow();

//Window window = getDialog().getWindow();如果是在activity中则用这段代码
window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
//window.requestWindowFeature(Window.FEATURE_NO_TITLE); 用在activity中，去标题
int uiOptions =View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
	|View.SYSTEM_UI_FLAG_LAYOUT_STABLE
	|View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
	|View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
	|View.SYSTEM_UI_FLAG_IMMERSIVE
	|View.SYSTEM_UI_FLAG_FULLSCREEN

window.getDecorView().setSystemUiVisibility(uiOptions);
}