car_product/car_ui_portrait/apps/CarUiPortraitSystemUI/res/drawable/hvac_decrease_button.xml

<?xml version="1.0" encoding="utf-8" ?>
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  ~ Copyright (C) 2021 The Android Open Source Project
  ~
  ~ Licensed under the Apache License, Version 2.0 (the "License");
  ~ you may not use this file except in compliance with the License.
  ~ You may obtain a copy of the License at
  ~
  ~      http://www.apache.org/licenses/LICENSE-2.0
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  ~ distributed under the License is distributed on an "AS IS" BASIS,
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  ~ See the License for the specific language governing permissions and
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<layer-list
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:aapt="http://schemas.android.com/aapt">
    <item>
        <aapt:attr name="android:drawable">
            <vector android:width="@dimen/hvac_temperature_button_size"
                    android:height="@dimen/hvac_temperature_button_size"
                    android:viewportWidth="64"
                    android:viewportHeight="64">
                <path
                    android:pathData="M32,0L32,0A32,32 0,0 1,64 32L64,32A32,32 0,0 1,32 64L32,64A32,32 0,0 1,0 32L0,32A32,32 0,0 1,32 0z"
                    android:fillColor="@color/hvac_temperature_adjust_button_color"/>
            </vector>
        </aapt:attr>
    </item>
    <item android:gravity="center">
        <aapt:attr name="android:drawable">
            <vector android:width="24dp"
                    android:height="3dp"
                    android:viewportWidth="24"
                    android:viewportHeight="3">
                <path
                    android:fillColor="@color/hvac_temperature_decrease_arrow_color"
                    android:pathData="M24,3.5H0V0.5H24V3.5Z"/>
            </vector>
        </aapt:attr>
    </item>
    <item>
        <aapt:attr name="android:drawable">
            <ripple android:color="?android:attr/colorControlHighlight"/>
        </aapt:attr>
    </item>
</layer-list>