可以使用 GradientColor 完全在 XML 中定义填充或描边的渐变吗？
Can GradientColor be used to define a gradient for a fill or stroke entirely in XML?
我正在查看 GradientColor https://developer.android.com/reference/android/R.styleable.html#GradientColor 的文档。如何在 XML 中定义渐变颜色并将其应用于 XML 矢量可绘制对象？
我已经在 color.xml、styles.xml 和 XML 矢量绘图中尝试过。
我收到错误消息“无法将 @id/gradclor 转换为 ColorStateList”：
<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="120dp"
android:height="120dp"
android:viewportWidth="120.0"
android:viewportHeight="120.0">
<path
android:name="play_triangle"
android:pathData="M 30 30 L 30 90 L 80 60 z"
android:strokeColor="@id/gradclor"
android:strokeWidth="5"/>
<color
android:name="@+id/gradclor"
android:startColor="#FFFFFF"
android:endColor="#00FFFF"
android:angle="145"/>
</vector>
或
"Failed to convert #FFFFFFFF #00FFFFFF 145 into a ColorStateList" 使用时：
<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="120dp"
android:height="120dp"
android:viewportWidth="120.0"
android:viewportHeight="120.0">
<path
android:name="play_triangle"
android:pathData="M 30 30 L 30 90 L 80 60 z"
android:strokeColor="@color/GradientStrokeBorder"
android:strokeWidth="5"/>
</vector>
在 color.xml 中包含以下内容：
<color name="GradientStrokeBorder">
<item name="android:startColor">#FFFFFF</item>
<item name="android:endColor">#00FFFF</item>
<item name="android:angle">145</item>
</color>
我终于成功了。 Android Studio（当前版本为 2.2）尚不支持渐变颜色功能，因此它无法帮助您自动完成，而是将渐变标记标记为错误。尽管如此，该功能确实有效，我已经在 Nexus 5X / API 24 上成功测试了它。当然，您必须使用 API 24+ 设备，否则 OS.
首先，你需要添加这样的颜色资源文件：
<?xml version="1.0" encoding="utf-8"?>
<gradient xmlns:android="http://schemas.android.com/apk/res/android"
android:startColor="#FFFFFF"
android:centerColor="#0000FF"
android:endColor="#00FFFF"
android:angle="145"
android:startX="30"
android:endX="70"
android:startY="30"
android:endY="70"
android:type="linear"/>
请注意 start/end 参数，因为我发现它们对于矢量梯度至关重要。
将此文件以某个名称放入 res/color 文件夹中。我将其命名为 gradient.xml，因此完整路径为 res/color/gradient.xml。之后你可以在颜色属性中引用这个资源，包括矢量路径颜色：
<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="120dp"
android:height="120dp"
android:viewportWidth="120.0"
android:viewportHeight="120.0">
<path
android:name="play_triangle"
android:pathData="M 30 30 L 30 90 L 80 60 z"
android:strokeWidth="10"
android:strokeColor="@color/gradient"/>
</vector>
注意strokeColor中对渐变颜色资源的引用。希望这对您有所帮助！
我不确定，但根据 this document:
android:strokeColor
Specifies the color used to draw the path outline. May be a color or, for SDK 24+, a color state list or a gradient color (See GradientColor and GradientColorItem). If this property is animated, any value set by the animation will override the original value. No path outline is drawn if this property is not specified.
如果您的 SDK 小于 24，则它应该只是一种颜色。
另一方面，如果您的 sdk 大于 24，我认为最好使用 <gradient/> 来填充您的路径而不是 <color/>
Android 的最新预览版 (3.1 Canary 6) 包含一个使用渐变矢量资源的示例。
<vector xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:aapt="http://schemas.android.com/aapt"
android:width="108dp"
android:height="108dp"
android:viewportHeight="108"
android:viewportWidth="108">
<path
android:fillType="evenOdd"
android:pathData="M32,64C32,64 38.39,52.99 44.13,50.95C51.37,48.37 70.14,49.57 70.14,49.57L108.26,87.69L108,109.01L75.97,107.97L32,64Z"
android:strokeColor="#00000000"
android:strokeWidth="1">
<aapt:attr name="android:fillColor">
<gradient
android:endX="78.5885"
android:endY="90.9159"
android:startX="48.7653"
android:startY="61.0927"
android:type="linear">
<item
android:color="#44000000"
android:offset="0.0" />
<item
android:color="#00000000"
android:offset="1.0" />
</gradient>
</aapt:attr>
</path>
<path
android:fillColor="#FFFFFF"
android:fillType="nonZero"
android:pathData="M66.94,46.02L66.94,46.02C72.44,50.07 76,56.61 76,64L32,64C32,56.61 35.56,50.11 40.98,46.06L36.18,41.19C35.45,40.45 35.45,39.3 36.18,38.56C36.91,37.81 38.05,37.81 38.78,38.56L44.25,44.05C47.18,42.57 50.48,41.71 54,41.71C57.48,41.71 60.78,42.57 63.68,44.05L69.11,38.56C69.84,37.81 70.98,37.81 71.71,38.56C72.44,39.3 72.44,40.45 71.71,41.19L66.94,46.02ZM62.94,56.92C64.08,56.92 65,56.01 65,54.88C65,53.76 64.08,52.85 62.94,52.85C61.8,52.85 60.88,53.76 60.88,54.88C60.88,56.01 61.8,56.92 62.94,56.92ZM45.06,56.92C46.2,56.92 47.13,56.01 47.13,54.88C47.13,53.76 46.2,52.85 45.06,52.85C43.92,52.85 43,53.76 43,54.88C43,56.01 43.92,56.92 45.06,56.92Z"
android:strokeColor="#00000000"
android:strokeWidth="1" />
</vector>
我正在查看 GradientColor https://developer.android.com/reference/android/R.styleable.html#GradientColor 的文档。如何在 XML 中定义渐变颜色并将其应用于 XML 矢量可绘制对象？
我已经在 color.xml、styles.xml 和 XML 矢量绘图中尝试过。
我收到错误消息“无法将 @id/gradclor 转换为 ColorStateList”：
<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="120dp"
android:height="120dp"
android:viewportWidth="120.0"
android:viewportHeight="120.0">
<path
android:name="play_triangle"
android:pathData="M 30 30 L 30 90 L 80 60 z"
android:strokeColor="@id/gradclor"
android:strokeWidth="5"/>
<color
android:name="@+id/gradclor"
android:startColor="#FFFFFF"
android:endColor="#00FFFF"
android:angle="145"/>
</vector>
或 "Failed to convert #FFFFFFFF #00FFFFFF 145 into a ColorStateList" 使用时：
<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="120dp"
android:height="120dp"
android:viewportWidth="120.0"
android:viewportHeight="120.0">
<path
android:name="play_triangle"
android:pathData="M 30 30 L 30 90 L 80 60 z"
android:strokeColor="@color/GradientStrokeBorder"
android:strokeWidth="5"/>
</vector>
在 color.xml 中包含以下内容：
<color name="GradientStrokeBorder">
<item name="android:startColor">#FFFFFF</item>
<item name="android:endColor">#00FFFF</item>
<item name="android:angle">145</item>
</color>
我终于成功了。 Android Studio（当前版本为 2.2）尚不支持渐变颜色功能，因此它无法帮助您自动完成，而是将渐变标记标记为错误。尽管如此，该功能确实有效，我已经在 Nexus 5X / API 24 上成功测试了它。当然，您必须使用 API 24+ 设备，否则 OS.
首先，你需要添加这样的颜色资源文件：
<?xml version="1.0" encoding="utf-8"?>
<gradient xmlns:android="http://schemas.android.com/apk/res/android"
android:startColor="#FFFFFF"
android:centerColor="#0000FF"
android:endColor="#00FFFF"
android:angle="145"
android:startX="30"
android:endX="70"
android:startY="30"
android:endY="70"
android:type="linear"/>
请注意 start/end 参数，因为我发现它们对于矢量梯度至关重要。
将此文件以某个名称放入 res/color 文件夹中。我将其命名为 gradient.xml，因此完整路径为 res/color/gradient.xml。之后你可以在颜色属性中引用这个资源，包括矢量路径颜色：
<?xml version="1.0" encoding="utf-8"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:width="120dp"
android:height="120dp"
android:viewportWidth="120.0"
android:viewportHeight="120.0">
<path
android:name="play_triangle"
android:pathData="M 30 30 L 30 90 L 80 60 z"
android:strokeWidth="10"
android:strokeColor="@color/gradient"/>
</vector>
注意strokeColor中对渐变颜色资源的引用。希望这对您有所帮助！
我不确定，但根据 this document:
android:strokeColor Specifies the color used to draw the path outline. May be a color or, for SDK 24+, a color state list or a gradient color (See GradientColor and GradientColorItem). If this property is animated, any value set by the animation will override the original value. No path outline is drawn if this property is not specified.
如果您的 SDK 小于 24，则它应该只是一种颜色。
另一方面，如果您的 sdk 大于 24，我认为最好使用 <gradient/> 来填充您的路径而不是 <color/>
Android 的最新预览版 (3.1 Canary 6) 包含一个使用渐变矢量资源的示例。
<vector xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:aapt="http://schemas.android.com/aapt"
android:width="108dp"
android:height="108dp"
android:viewportHeight="108"
android:viewportWidth="108">
<path
android:fillType="evenOdd"
android:pathData="M32,64C32,64 38.39,52.99 44.13,50.95C51.37,48.37 70.14,49.57 70.14,49.57L108.26,87.69L108,109.01L75.97,107.97L32,64Z"
android:strokeColor="#00000000"
android:strokeWidth="1">
<aapt:attr name="android:fillColor">
<gradient
android:endX="78.5885"
android:endY="90.9159"
android:startX="48.7653"
android:startY="61.0927"
android:type="linear">
<item
android:color="#44000000"
android:offset="0.0" />
<item
android:color="#00000000"
android:offset="1.0" />
</gradient>
</aapt:attr>
</path>
<path
android:fillColor="#FFFFFF"
android:fillType="nonZero"
android:pathData="M66.94,46.02L66.94,46.02C72.44,50.07 76,56.61 76,64L32,64C32,56.61 35.56,50.11 40.98,46.06L36.18,41.19C35.45,40.45 35.45,39.3 36.18,38.56C36.91,37.81 38.05,37.81 38.78,38.56L44.25,44.05C47.18,42.57 50.48,41.71 54,41.71C57.48,41.71 60.78,42.57 63.68,44.05L69.11,38.56C69.84,37.81 70.98,37.81 71.71,38.56C72.44,39.3 72.44,40.45 71.71,41.19L66.94,46.02ZM62.94,56.92C64.08,56.92 65,56.01 65,54.88C65,53.76 64.08,52.85 62.94,52.85C61.8,52.85 60.88,53.76 60.88,54.88C60.88,56.01 61.8,56.92 62.94,56.92ZM45.06,56.92C46.2,56.92 47.13,56.01 47.13,54.88C47.13,53.76 46.2,52.85 45.06,52.85C43.92,52.85 43,53.76 43,54.88C43,56.01 43.92,56.92 45.06,56.92Z"
android:strokeColor="#00000000"
android:strokeWidth="1" />
</vector>