如何在android中从上到下显示渐变效果
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How to display gradient effect from top to bottom in android
提问by mohan
can anybody tell How to dispaly gradient effect from top to bottom in android .can anybody provide example
任何人都可以告诉如何在android中从上到下显示渐变效果。任何人都可以提供示例
Thanks
谢谢
回答by Adil Soomro
make an xml file in your dawable folder name it like gradient_bg.xml
在你的 dawable 文件夹中创建一个 xml 文件，将其命名为 gradient_bg.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<gradient
android:startColor="#000"
android:endColor="#fff"
android:angle="90"
/>
</shape>
and set it as background to your View.
并将其设置为您的View.
android:background="@drawable/gradient_bg"
or
或者
setBackgroundResource(R.drawable.gradient_bg);
回答by confucius
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
<gradient
android:angle="90"
android:type="linear"
android:startColor="#FFFFFF"
android:endColor="#000000" />
</shape>
here if you set the angle to the 270the start color will appear at the bottom and the end color at the top
if you set the angle to 90it will be reversed
在这里，如果您将角度设置为270起始颜色将出现在底部，而如果您将角度设置为顶部，则结束颜色90将被反转
回答by lopez.mikhael
You can used a custom view to do that. With this solution, it's finished the gradient shapes of all colors in your projects:
您可以使用自定义视图来做到这一点。使用此解决方案，它完成了项目中所有颜色的渐变形状：
class GradientView(context: Context, attrs: AttributeSet) : View(context, attrs) {
// Properties
private val paint: Paint = Paint()
private val rect = Rect()
//region Attributes
var start: Int = Color.WHITE
var end: Int = Color.WHITE
//endregion
override fun onSizeChanged(w: Int, h: Int, oldw: Int, oldh: Int) {
super.onSizeChanged(w, h, oldw, oldh)
// Update Size
val usableWidth = width - (paddingLeft + paddingRight)
val usableHeight = height - (paddingTop + paddingBottom)
rect.right = usableWidth
rect.bottom = usableHeight
// Update Color
paint.shader = LinearGradient(0f, height.toFloat(), 0f, 0f,
start, end, Shader.TileMode.CLAMP)
// ReDraw
invalidate()
}
override fun onDraw(canvas: Canvas) {
super.onDraw(canvas)
canvas.drawRect(rect, paint)
}
}
I also create an open source project GradientViewwith this custom view:
我还使用这个自定义视图创建了一个开源项目GradientView：
https://github.com/lopspower/GradientView
https://github.com/lopspower/GradientView
implementation 'com.mikhaellopez:gradientview:1.1.0'
回答by Pacific P. Regmi
To display gradient effect from top to bottom in android with transparent:
在android中以透明方式显示从上到下的渐变效果：
- Create a new XML file in res/drawable folder with the name gradient_transparent.xml and add following code.
- 在 res/drawable 文件夹中创建一个名为 gradient_transparent.xml 的新 XML 文件并添加以下代码。
.
.
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<gradient
android:startColor="#90000000"
android:endColor="#00ffffff"
android:angle="90"
/>
</shape>
In XML Layout file
在 XML 布局文件中
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="@drawable/gradient_transparent"
android:orientation="vertical"
android:padding="@dimen/spacing_middle">
</LinearLayout>
