Android 检索项的父项时出错：未找到与给定名称匹配的资源'；安卓：主题。材质。灯光'；

我在styles.xml中遇到此错误：

检索项的父项时出错：未找到与 命名为“android:Theme.Material.Light”

在清单中：

<uses-sdk
    android:minSdkVersion="16"
    android:targetSdkVersion="21" />

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <style name="AppTheme" parent="android:Theme.Material.Light">

        <item name="android:colorPrimary">@color/primary</item>
        <item name="android:colorPrimaryDark">@color/primary_dark</item>
        <item name="android:colorAccent">@color/accent</item>
        <item name="android:textColorPrimary">@color/text_primary</item>
        <item name="android:textColor">@color/text_secondary</item>
        <item name="android:navigationBarColor">@color/primary_dark</item>

    </style>
</resources>  

E:\workspace\WelcomeToL\app\src\main\res\values-v21\styles.xml:3: error: Error retrieving parent for item: No resource found that matches the given name 'android:Theme.Material.Light'.

E:\workspace\WelcomeToL\app\src\main\res\values-v21\styles.xml:7: error: Error: No resource found that matches the given name: attr 'android:colorAccent'.
 
E:\workspace\WelcomeToL\app\src\main\res\values-v21\styles.xml:5: error: Error: No resource found that matches the given name: attr 'android:colorPrimary'.
 
E:\workspace\WelcomeToL\app\src\main\res\values-v21\styles.xml:6: error: Error: No resource found that matches the given name: attr 'android:colorPrimaryDark'.

E:\workspace\WelcomeToL\app\src\main\res\values-v21\styles.xml:10: error: Error: No resource found that matches the given name: attr 'android:navigationBarColor'.

我不知道为什么这个错误仍然发生。任何人都可以帮助我。谢谢

检索项的父项时出错：未找到与 命名为“android:Theme.Material.Light”

---

Material.Light

主题要求项目API级别为21。为从

属性->Android->Project Build Target

到

API 21

的项目设置项目构建目标，targetSdkVersion可以小于21，但compileSdkVersion必须大于等于21