Spinner with arrow in left

You must write a custom spinner. Sample code is below. You can edit as you wish.

<Spinner
            style="@style/spinner_style"
            android:layout_width="match_parent"
            android:layout_height="wrap content"
             />

@style/spinner_style:

 <style name="spinner_style">
    <item name="android:background">@drawable/background_spinner</item>
</style>

@drawable/background_spinner

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item><layer-list>
        <item><shape>
               <solid android:color="@android:color/white" />
                <corners android:radius="4dp" />
                <padding android:left="8dp"/>
            </shape></item>
        <item><bitmap android:gravity="left"
              android:src="@drawable/ic_arrow_drop_down_grey600_36dp"/>                
        </item>
    </layer-list></item>
</selector>

An easy and simple way to set arrow in left side is,You must create .xml file in drawable folder for that as written below:

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

   <item>
        <shape android:shape="rectangle">
            <solid android:color="@color/colorWhite" />
        </shape>
   </item>
   <item
        android:drawable="@drawable/ic_arrow_drop_down_black_24dp"
        android:right="320dp"/>
</layer-list>

You can adjust above code as your need. And set this file as background of a spinner widget as below:

<Spinner
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/layout_spinner"
        android:background="@drawable/arrow_left"
        android:elevation="5dp"/>