llll.gitpractice/Notes-master/res/drawable/new_note.xml

<?xml version="1.0" encoding="utf-8"?>

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<!-- 定义一个 Drawable 状态选择器（State List Drawable），用于根据视图的状态动态切换背景或图片 -->
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- 当视图被按下时（state_pressed=true），使用此 Drawable 资源 -->
    <!-- android:drawable="@drawable/new_note_pressed" 表示按下状态时显示的图片资源 -->
    <item android:state_pressed="true"
        android:drawable="@drawable/new_note_pressed" />
    <!-- 默认 Drawable 资源，当没有其他状态匹配时使用 -->
    <!-- android:drawable="@drawable/new_note_normal" 表示正常状态时显示的图片资源 -->
    <item
        android:drawable="@drawable/new_note_normal" />
</selector>