调用下面这个方法就可以让状态栏透明，那么布局都会延伸到状态栏
public void setTraspartenStatusBar() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {Window window = getWindow();
window.clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS
| WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
window.getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
| View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_LAYOUT_STABLE);
window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
window.setStatusBarColor(Color.TRANSPARENT);
window.setNavigationBarColor(Color.TRANSPARENT);
}
}