App一般会有多套颜色主题，下面介绍如何在App中添加主题切换功能：

1. 先添加自定义属性，在values目录下新建attr.xml，根据主题中需要动态修改的颜色或者图片设定自定义属性

<?xml version="1.0" encoding="utf-8"?>
<resources><attr name="main_bg_color" format="color"/><attr name="nav_head_bg" format="color"/><attr name="text1_color" format="color"/><attr name="text2_color" format="color"/><attr name="text3_color" format="color"/><attr name="text4_color" format="color"/><attr name="text5_color" format="color"/>
</resources>

1. 在colors.xml添加主题颜色配置

<?xml version="1.0" encoding="utf-8"?>
<resources><color name="purple_500">#1afa29</color><color name="purple_700">#afdd22</color><color name="teal_200">#FF03DAC5</color><color name="teal_700">#FF018786</color><color name="black">#FF000000</color><color name="white">#FFFFFFFF</color><color name="tab_sel">#1afa29</color><color name="tab_normal">#bfbfbf</color><color name="title_1">#000000</color><color name="title_2">#333333</color><color name="title_3">#666666</color><color name="title_4">#999999</color><color name="title_5">#CCCCCC</color><color name="banner_bg">#66CCCCCC</color><color name="purple_500_blue">#6699FF</color><color name="purple_700_blue">#3366FF</color><color name="teal_200_blue">#9999FF</color><color name="teal_700_blue">#6633FF</color><color name="title_1_blue">#0000CC</color><color name="title_2_blue">#0000FF</color><color name="title_3_blue">#0033FF</color><color name="title_4_blue">#0066FF</color><color name="title_5_blue">#0099FF</color><color name="main_gb_blue">#00CCFF</color>
</resources>

1. 配置themes.xml，设置不同颜色主题配置

 <style name="Theme.JetpackDemo.main" parent="Theme.JetpackDemo.Base"><!-- Primary brand color. --><item name="colorPrimary">@color/purple_500</item><item name="colorPrimaryVariant">@color/purple_700</item><item name="colorPrimaryDark">@color/purple_700</item><item name="colorOnPrimary">@color/white</item><!-- Secondary brand color. --><item name="colorSecondary">@color/teal_200</item><item name="colorSecondaryVariant">@color/teal_700</item><item name="colorOnSecondary">@color/black</item><item name="main_bg_color">@color/white</item><item name="nav_head_bg">@drawable/side_nav_bar</item><item name="text1_color">@color/title_1</item><item name="text2_color">@color/title_2</item><item name="text3_color">@color/title_3</item><item name="text4_color">@color/title_4</item><item name="text5_color">@color/title_5</item></style><style name="Theme.JetpackDemo.Blue" parent="Theme.JetpackDemo.Base"><!-- Primary brand color. --><item name="colorPrimary">@color/purple_500_blue</item><item name="colorPrimaryVariant">@color/purple_700_blue</item><item name="colorPrimaryDark">@color/purple_700_blue</item><!-- Secondary brand color. --><item name="colorSecondary">@color/teal_200_blue</item><item name="colorSecondaryVariant">@color/teal_700_blue</item><item name="main_bg_color">@color/main_gb_blue</item><item name="nav_head_bg">@drawable/side_nav_bar_blue</item><item name="text1_color">@color/title_1_blue</item><item name="text2_color">@color/title_2_blue</item><item name="text3_color">@color/title_3_blue</item><item name="text4_color">@color/title_4_blue</item><item name="text5_color">@color/title_5_blue</item></style>

1. 界面配置设置的自定义属性

<TextViewandroid:textSize="16sp"android:textColor="?attr/text1_color"android:text="@{top.title}"android:id="@+id/tv_title"android:layout_width="wrap_content"android:layout_height="wrap_content"></TextView>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:background="?attr/main_bg_color"android:fitsSystemWindows="true"android:orientation="vertical">

1. 代码设置当前主题

        super.onCreate(savedInstanceState);int theme = MmkvUtil.getInstance().getInt(Constant.THEME_KEY);if (theme == Constant.THEME_BLUE){setTheme(R.style.Theme_JetpackDemo_Blue);}else {setTheme(R.style.Theme_JetpackDemo_main);}binding = ActivityMainBinding.inflate(getLayoutInflater());setContentView(binding.getRoot());

1. 选择切换主题

                        int theme = MmkvUtil.getInstance().getInt(Constant.THEME_KEY);if (theme == Constant.THEME_BLUE){MmkvUtil.getInstance().setInt(Constant.THEME_KEY,Constant.THEME_MAIN);}else {MmkvUtil.getInstance().setInt(Constant.THEME_KEY,Constant.THEME_BLUE);}Intent intent = new Intent(MainActivity.this,MainActivity.class);intent.setFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);startActivity(intent);finish();overridePendingTransition(0,0);

效果如下：