Android Code Snippet Shadow Button with Ripple Effect

#Region Shared Files
#CustomBuildAction: folders ready, %WINDIR%\System32\Robocopy.exe,"..\..\Shared Files" "..\Files"
'Ctrl + click to sync files: ide://run?file=%WINDIR%\System32\Robocopy.exe&args=..\..\Shared+Files&args=..\Files&FilesSync=True
#End Region

#Macro: Title, Export B4XPages, ide://run?File=%B4X%\Zipper.jar&Args=%PROJECT_NAME%.zip

Sub Class_Globals
    Private Root As B4XView
    Private xui As XUI
    
    Dim mainColorb As Int = 0xFF3B3B3B
    Dim lightColorb As Int = 0xFF51555B
    Dim darkColorb As Int  = 0xFF000000
    
    Dim mainColor As Int = 0xFFE0E5EC
    Dim lightColor As Int = 0xFFFFFFFF
    Dim darkColor As Int  = 0xFFA3B1C6
    
    Private btn1, btn2, btn3, btn4 As Button
    Private Panel1, Panel2 As Panel
End Sub

Public Sub Initialize
'    B4XPages.GetManager.LogEvents = True
End Sub

'This event will be called once, before the page becomes visible.
Private Sub B4XPage_Created (Root1 As B4XView)
    Root = Root1
    Root.LoadLayout("MainPage")
    
    Panel1.Color = mainColor
    Panel2.Color = mainColorb
    
    GenerateViewShadow(btn1, btn1.Width/2, 0.2)
    GenerateViewShadow(btn2, btn2.Width/24, 0.2)
    
    GenerateViewShadow1(btn3, btn3.Width/2, 0.2)
    GenerateViewShadow1(btn4, btn4.Width/24, 0.2)
    AddRippleToAllButtons
    AddRippleToAllButtons1
End Sub

Private Sub AddRippleToAllButtons
    Dim ripple As RippleView
    Dim btns As List = Array As B4XView(btn1, btn2)
    
    For Each btn As B4XView In btns
        ripple.Initialize(btn, Colors.Black, 300, True)
    Next
End Sub

Private Sub AddRippleToAllButtons1
    Dim ripple As RippleView
    Dim btns As List = Array As B4XView(btn3, btn4)
    
    For Each btn As B4XView In btns
        ripple.Initialize(btn, Colors.White, 300, True)
    Next
End Sub

Sub createLabel(myText As String) As Label
    Dim l As Label
    l.Initialize("")
    l.Gravity = Gravity.CENTER
    l.TextColor = Colors.Red
    l.TextSize = 20
    l.Text = myText
    Return l
End Sub
    
    
Sub GenerateViewShadow( P As B4XView, cornerRadius As Int, insetPercentage As Float)

    Dim BigWW As Int  = P.Width
    Dim BigHH As Int = P.Height
    
    ' inset percentage will be according to the smallest dim, but will be the same for both direction
    Dim absInset As Float = insetPercentage*Min(BigWW, BigHH)
    Dim SmallWW As Int = BigWW - absInset
    Dim SmallHH As Int = BigHH - absInset

    Dim CVX As B4XCanvas
    CVX.Initialize(P)

    Dim PX As B4XPath
    Dim R0 As B4XRect
    Dim dW As Int = (BigWW-SmallWW)/2
    Dim dH As Int = (BigHH-SmallHH)/2
    Dim d As Int = Max(dW, dH)
    
    ' UPPER (light) shadow
    For k = 0 To d
        Dim kW As Float = k*dW/d
        Dim kH As Float = k*dH/d
        R0.Initialize( kW , kH, SmallWW+dW-kW, SmallHH+dH-kH)
        PX.InitializeRoundedRect(R0, cornerRadius)
        CVX.ClipPath(PX)
        Dim pColor As Int = FindSolidColorBetween(mainColor, lightColor, 1.0*k*k*k/(d*d*d))
        CVX.DrawRect(R0, pColor, True, 0)
        CVX.RemoveClip
    Next

    ' LOWER (dark) shadow
    For k = 0 To d
        Dim kW As Float = k*dW/d
        Dim kH As Float = k*dH/d
        R0.Initialize( 2*dW-kW , 2*dH-kH, 2*dW+SmallWW-kW, 2*dH+SmallHH-kH)
        PX.InitializeRoundedRect(R0, cornerRadius)
        CVX.ClipPath(PX)
        Dim pColor As Int = FindSolidColorBetween(mainColor, darkColor, 1.0*k*k*k/(d*d*d))
        CVX.DrawRect(R0, pColor, True, 0)
        CVX.RemoveClip
    Next

    ' Draw the 'plain' area with the main color.
    R0.Initialize( dW , dH, dW+SmallWW, dH+SmallHH)
    PX.InitializeRoundedRect(R0, cornerRadius)
    CVX.ClipPath(PX)
    CVX.DrawRect(R0, mainColor, True, 0)
    CVX.RemoveClip
End Sub


Sub GenerateViewShadow1( P As B4XView, cornerRadius As Int, insetPercentage As Float)

    Dim BigWW As Int  = P.Width
    Dim BigHH As Int = P.Height
    
    ' inset percentage will be according to the smallest dim, but will be the same for both direction
    Dim absInset As Float = insetPercentage*Min(BigWW, BigHH)
    Dim SmallWW As Int = BigWW - absInset
    Dim SmallHH As Int = BigHH - absInset

    Dim CVX As B4XCanvas
    CVX.Initialize(P)

    Dim PX As B4XPath
    Dim R0 As B4XRect
    Dim dW As Int = (BigWW-SmallWW)/2
    Dim dH As Int = (BigHH-SmallHH)/2
    Dim d As Int = Max(dW, dH)
    
    ' UPPER (light) shadow
    For k = 0 To d
        Dim kW As Float = k*dW/d
        Dim kH As Float = k*dH/d
        R0.Initialize( kW , kH, SmallWW+dW-kW, SmallHH+dH-kH)
        PX.InitializeRoundedRect(R0, cornerRadius)
        CVX.ClipPath(PX)
        Dim pColor As Int = FindSolidColorBetween(mainColorb, lightColorb, 1.0*k*k*k/(d*d*d))
        CVX.DrawRect(R0, pColor, True, 0)
        CVX.RemoveClip
    Next

    ' LOWER (dark) shadow
    For k = 0 To d
        Dim kW As Float = k*dW/d
        Dim kH As Float = k*dH/d
        R0.Initialize( 2*dW-kW , 2*dH-kH, 2*dW+SmallWW-kW, 2*dH+SmallHH-kH)
        PX.InitializeRoundedRect(R0, cornerRadius)
        CVX.ClipPath(PX)
        Dim pColor As Int = FindSolidColorBetween(mainColorb, darkColorb, 1.0*k*k*k/(d*d*d))
        CVX.DrawRect(R0, pColor, True, 0)
        CVX.RemoveClip
    Next

    ' Draw the 'plain' area with the main color.
    R0.Initialize( dW , dH, dW+SmallWW, dH+SmallHH)
    PX.InitializeRoundedRect(R0, cornerRadius)
    CVX.ClipPath(PX)
    CVX.DrawRect(R0, mainColorb, True, 0)
    CVX.RemoveClip
End Sub

' progress=0 --> we get colorA
' progress=1 -> we get colorB
Sub FindSolidColorBetween(colorA As Int, colorB As Int, progress As Float) As Int
    Dim weight As Int = 256*(1-Max(0, Min(progress, 1)))
    Dim finalRed As Int   = Bit.ShiftRight(weight*Bit.And(Bit.ShiftRight(colorA,16),0xFF) + (256-weight)*Bit.And(Bit.ShiftRight(colorB,16),0xFF),8)
    Dim finalGreen As Int = Bit.ShiftRight(weight*Bit.And(Bit.ShiftRight(colorA, 8),0xFF) + (256-weight)*Bit.And(Bit.ShiftRight(colorB, 8),0xFF),8)
    Dim finalBlue As Int  = Bit.ShiftRight(weight*Bit.And(Bit.ShiftRight(colorA, 0),0xFF) + (256-weight)*Bit.And(Bit.ShiftRight(colorB, 0),0xFF),8)
    Return Colors.RGB(finalRed, finalGreen, finalBlue)
End Sub