- 效果图
- 实现原理
- 代码
- 创建自定义属性
- 自定义控件
- 使用方法
- PorterDuff.Mode 简介
- 示例图
- 代码示例
- PorterDuff.Mode 效果图示
- 1. ADD
- 2. CLEAR
- 3. DARKEN
- 4. DST
- 5. DST_ATOP
- 6. DST_IN
- 7. DST_OUT
- 8. DST_OVER
- 9. LIGHTEN
- 10. MULTIPLY
- 11. OVERLAY
- 12. SCREEN
- 13. SRC
- 14. SRC_ATOP
- 15. SRC_IN
- 16. SRC_OUT
- 17. SRC_OVER
- 18. XOR
[TOC]
效果图
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实现原理
通过设置 xfermode 取光亮与底下的像素的最大亮度,来实现闪光遮照。
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代码
创建自定义属性
<declare-styleable name="MyFlashLightingView">
<attr name="roundedCornerRadius" format="dimension"/>
<attr name="animDuration" format="float"/>
</declare-styleable>
属性 | 描述 |
---|---|
roundedCornerRadius | 圆角角度,dp |
animDuration | 闪光从左到右时间,秒,Float |
自定义控件
import android.animation.ValueAnimator
import android.animation.ValueAnimator.INFINITE
import android.content.Context
import android.graphics.*
import android.util.AttributeSet
import android.view.View
/**
* @author Afra55
* @date 2020/7/30
* A smile is the best business card.
* https://developer.android.com/reference/android/graphics/PorterDuff.Mode
*/
class MyFlashLightingView : View {
constructor(context: Context) : super(context) {
init(null, 0)
}
constructor(context: Context, attrs: AttributeSet) : super(context, attrs) {
init(attrs, 0)
}
constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int) : super(
context,
attrs,
defStyleAttr
) {
init(attrs, defStyleAttr)
}
var flashPaint: Paint? = null
/**
* 圆角大小,px
*/
var roundedCornerSize = 0F
var gradient: LinearGradient? = null
var gradientMatrix: Matrix? = null
var rect: RectF? = null
/**
* 动画,用来让闪光移动
*/
var valueAnimator: ValueAnimator? = null
/**
* 动画时间,秒
*/
var animDuration = 3F
private fun init(attrs: AttributeSet?, defStyle: Int) {
val a = context.obtainStyledAttributes(
attrs, R.styleable.MyFlashLightingView, defStyle, 0
)
roundedCornerSize = a.getDimension(
R.styleable.MyFlashLightingView_roundedCornerRadius,
roundedCornerSize
)
animDuration = a.getFloat(R.styleable.MyFlashLightingView_animDuration, animDuration)
a.recycle()
flashPaint = Paint(Paint.ANTI_ALIAS_FLAG)
gradientMatrix = Matrix()
rect = RectF()
valueAnimator = ValueAnimator.ofFloat(0F, 1F)
valueAnimator?.repeatCount = INFINITE
valueAnimator?.duration = (animDuration * 1000).toLong()
valueAnimator?.addUpdateListener {
try {
val v = it.animatedValue as Float
// 通过 matrix translate 移动闪光, 从 -width 移动到 2 * width, 整个移动长度是 3 * width, 起点是 -width, 高度可以不移动
// TODO: 整个长度按需修改
gradientMatrix?.setTranslate(-width + width * 3 * v, height * v)
gradient?.setLocalMatrix(gradientMatrix)
postInvalidate()
} catch (e: Exception) {
}
}
}
fun startAnim() {
valueAnimator?.start()
}
override fun onSizeChanged(w: Int, h: Int, oldw: Int, oldh: Int) {
super.onSizeChanged(w, h, oldw, oldh)
// 设置渐变光亮
gradient = LinearGradient(
0F,
0F,
w / 2F,
h.toFloat(), // 前面4个参数,渐变角度
// 一共设置了五种渐变颜色,透明,微白,白,微白,透明
intArrayOf(0x00ffffff, 0x33ffffff, 0x65ffffff, 0x33ffffff, 0x00ffffff),
// 五种渐变颜色所在控件的相对位置
floatArrayOf(0.0f, 0.25f, 0.5f, 0.75f, 1F),
Shader.TileMode.CLAMP // 如果着色器超出原始边界范围,会复制边缘颜色
)
flashPaint?.shader = gradient
// 设置 xfermode 取光亮与底下的像素的最大值
flashPaint?.xfermode = PorterDuffXfermode(PorterDuff.Mode.LIGHTEN)
// 先把光亮放到控件的左边 -width 到 0 处
// TODO, 如果控件高度高,因为 CLAMP 的原因,起始和结束的闪光不会移出去,这时候需要再往外挪闪光的位置, 同时整个闪光的移动范围也要增大
gradientMatrix?.setTranslate(-w.toFloat(), h.toFloat())
gradient?.setLocalMatrix(gradientMatrix)
// 绘制光亮的宽高,和控件宽高一致
rect?.set(0F, 0F, w.toFloat(), h.toFloat())
if (w > 0) {
post {
startAnim()
}
}
}
override fun onDraw(canvas: Canvas?) {
super.onDraw(canvas)
try {
if (rect != null && flashPaint != null) {
canvas?.drawRoundRect(
rect!!,
roundedCornerSize,
roundedCornerSize,
flashPaint!!
)
}
} catch (e: Exception) {
}
}
}
使用方法
它可以盖到任何控件上面:
<FrameLayout
android:layout_width="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_height="wrap_content">
<TextView
android:id="@+id/home_3_subscribe"
android:layout_width="261dp"
android:layout_gravity="center_horizontal"
android:layout_height="52dp"
android:background="@drawable/start_now_bg"
android:gravity="center"
android:text="Start now"
android:textColor="#FFFFFF"
android:textSize="18sp" />
<com.xxx.xxx.MyFlashLightingView
android:layout_width="261dp"
android:layout_gravity="center_horizontal"
app:roundedCornerRadius="8dp"
app:animDuration="2"
android:layout_height="52dp"/>
</FrameLayout>
PorterDuff.Mode 简介
https://developer.android.com/reference/android/graphics/PorterDuff.Mode
示例图
SRC 图:
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DST 图:
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代码示例
Paint paint = new Paint();
// DST 图
canvas.drawBitmap(destinationImage, 0, 0, paint);
PorterDuff.Mode mode = // choose a mode
paint.setXfermode(new PorterDuffXfermode(mode));
// SRC 图
canvas.drawBitmap(sourceImage, 0, 0, paint);
PorterDuff.Mode 效果图示
1. ADD
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2. CLEAR
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3. DARKEN
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4. DST
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5. DST_ATOP
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6. DST_IN
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7. DST_OUT
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8. DST_OVER
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9. LIGHTEN
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10. MULTIPLY
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11. OVERLAY
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12. SCREEN
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13. SRC
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14. SRC_ATOP
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15. SRC_IN
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16. SRC_OUT
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17. SRC_OVER
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18. XOR
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