ToolBar和ActionBar右边三个点的图标替换

这是通过Style去设定icon



通过Menu设定icon
可把自带的setting设置为always,再设置icon属性

xml version="1.0" encoding="utf-8"?>
xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
            android:id="@+id/action_settings"
        android:icon="@drawable/search_icon"
        android:orderInCategory="100"
        android:title="@string/action_settings"
        app:showAsAction="always" />