修改ActionBarDrawerToggle小汉堡箭头颜色

<resources>

<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
<!--toolbar小汉堡样式-->
<item name="drawerArrowStyle">@style/DrawerArrowStyle</item>
</style>

<!--小汉堡颜色为白色-->
<style name="DrawerArrowStyle" parent="@style/Widget.AppCompat.DrawerArrowToggle">
<item name="spinBars">true</item>
<item name="color">@android:color/white</item>
</style>

</resources>