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@mvasilova
Created December 9, 2019 08:18
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Divider for item's RecyclerView
import android.graphics.Canvas
import android.graphics.Paint
import android.graphics.Rect
import android.view.View
import androidx.core.graphics.withTranslation
import androidx.core.view.children
import androidx.recyclerview.widget.RecyclerView
class DividerItemDecoration(
private val strokeColor: Int,
private val strokeWidth: Int,
private val marginStart: Float = 0.0F,
private val marginEnd: Float = marginStart,
private val horizontalSpacing: Int = 0,
private val verticalSpacing: Int = horizontalSpacing
) : RecyclerView.ItemDecoration() {
private val dividerPaint = Paint().apply {
color = strokeColor
strokeWidth = this@DividerItemDecoration.strokeWidth.toFloat()
flags = Paint.ANTI_ALIAS_FLAG
}
override fun getItemOffsets(
outRect: Rect,
view: View,
parent: RecyclerView,
state: RecyclerView.State
) {
outRect.set(horizontalSpacing, verticalSpacing, horizontalSpacing, verticalSpacing)
}
override fun onDrawOver(canvas: Canvas, parent: RecyclerView, state: RecyclerView.State) {
parent.children.forEach { child ->
canvas.withTranslation(
x = 0.0F,
y = verticalSpacing.toFloat()
) {
val lineTopY = child.top - strokeWidth/ 2f
drawLine(
child.left + marginStart,
lineTopY,
child.right - marginEnd,
lineTopY,
dividerPaint
)
if (child.isLastItem(parent, state.itemCount)) {
val lineBottomY = child.bottom - strokeWidth/ 2f
drawLine(
child.left + marginStart,
lineBottomY,
child.right - marginEnd,
lineBottomY,
dividerPaint
)
}
}
}
}
private fun View.isLastItem(parent: RecyclerView, itemCount: Int) =
parent.getChildAdapterPosition(this) == itemCount - 1
}
//Usages
val divider = DividerItemDecoration(
ContextCompat.getColor(context!!, R.color.colorGray),
2.dpToPx,
marginStart = 0f,
marginEnd = 0f
)
recyclerView.addItemDecoration(divider)
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