It is a wrap for this Github project. I have combined the attached B4A project with this line chart. Sure you will figure it out.
Do at least the following:
1. Extract b4aLibraryFiles.zip and copy the library files to your additional libs folder
2. Extract DemoRes.zip and copy the folder and its contents to be on the same folder level as that of the /Files and /Objects folders of the B4A project.
It displays the dB value on the SoundMeter and at the same time draws a live line chart.
Take it for a test drive and enjoy!
Sample Code:
Do at least the following:
1. Extract b4aLibraryFiles.zip and copy the library files to your additional libs folder
2. Extract DemoRes.zip and copy the folder and its contents to be on the same folder level as that of the /Files and /Objects folders of the B4A project.
It displays the dB value on the SoundMeter and at the same time draws a live line chart.
Take it for a test drive and enjoy!
Sample Code:
B4X:
#Region Project Attributes
#ApplicationLabel: b4aSoundMeterNew
#VersionCode: 1
#VersionName:
'SupportedOrientations possible values: unspecified, landscape or portrait.
#SupportedOrientations: unspecified
#CanInstallToExternalStorage: False
#End Region
#AdditionalRes: ..\DemoRes
#Region Activity Attributes
#FullScreen: False
#IncludeTitle: True
#End Region
Sub Process_Globals
'These global variables will be declared once when the application starts.
'These variables can be accessed from all modules.
Dim t As Timer
End Sub
Sub Globals
'These global variables will be redeclared each time the activity is created.
'These variables can only be accessed from this module.
Dim bm As Bitmap
Dim bmd As BitmapDrawable
Private Button1 As Button
Private Button2 As Button
Private sm As SoundMeter
Dim bufsize As Int = 300 'set the data buffer size here i.e how many values to display in the plot area
Dim xlab(bufsize) As String
Private lc1 As RealTimeLineChart
Dim a As Int = 0
Dim xlabeltrack As Int = 0
End Sub
Sub Activity_Create(FirstTime As Boolean)
'Do not forget to load the layout file created with the visual designer. For example:
Activity.LoadLayout("main")
t.Initialize("t", 50)
bm.Initialize(File.DirAssets, "noise_disc.png")
bmd.Initialize(bm)
sm.BackgroundImage = bmd
lc1.GraphTitleColor = Colors.White
lc1.GraphTitleSkewX = -0.15
lc1.GraphTitleBold = True
lc1.GraphTitleTextSize = 15.0
lc1.GraphPlotAreaBackgroundColor = Colors.Black 'this will paint the plotting area DrakGray regardless of what GraphBackgroundColor has been set to
lc1.GraphBackgroundColor = Colors.Transparent 'this will paint everything within the outer frame to be white
lc1.GraphFrameColor = Colors.Red 'this adjusts only the outer frame color
lc1.GraphFrameWidth = 2.0
lc1.GraphBufferSize = bufsize
lc1.GraphTitle = "Sound Meter"
lc1.DomainLabelColor = Colors.Cyan
lc1.DomainLabelTextSize = 25
lc1.DomianLabel = "Sound Level"
lc1.YaxisRangeMode = lc1.YaxisMode_FIXED 'the other option is FIXED
lc1.YaxisRange(40.0, 100.0)
lc1.YaxisDivisions = 10
lc1.YaxisLabelTicks = 1
lc1.YaxisShowZero = True
lc1.YaxisTitleTextSize = 20.0
lc1.YaxisTitleColor = Colors.Green
lc1.YaxisGridLineColor = Colors.Yellow
lc1.YaxisLabelTextSize = 20
lc1.YaxisLabelColor = Colors.Green
lc1.YaxisLabelOrientation = 0
lc1.YaxisTitle = "dB"
'************************ If you comment this code then the x-axis labels will be the index value of the buffer
For i = 0 To bufsize - 1
xlab(i) = "" & i
Next
lc1.XAxisLabels = xlab
'*************************************************************************************************************
lc1.XaxisLabelTextSize = 20
lc1.XaxisLabelTextColor = Colors.Cyan
lc1.XaxisGridLineColor = Colors.Yellow
lc1.XaxisLabelOrientation = 0
lc1.XaxisDivisions = 30
lc1.XaxisLabelTicks = 1
lc1.LegendTextSize = 15.0
lc1.LegendTextColor = Colors.White
lc1.LegendBackgroundColor = Colors.Transparent
'setup for Line 1
lc1.Line_1_LineColor = Colors.Red
lc1.Line_1_LineWidth = 3.0
lc1.Line_1_DrawDash = False
lc1.Line_1_LegendText = ""
lc1.NumberOfLineCharts = 1
lc1.DrawTheGraphs
End Sub
Sub Activity_Resume
lc1.START
End Sub
Sub Activity_Pause (UserClosed As Boolean)
End Sub
Sub Button1_Click
t.Enabled = True
sm.StartdB
End Sub
Sub Button2_Click
sm.StopdB
t.Enabled = False
End Sub
Sub t_tick
lc1.addData(sm.dBValue, 0, 0, 0, 0)
a = a + 1
If a = 301 Then a = 0
If xlabeltrack = bufsize + 1 Then
xlabeltrack = 0
lc1.ClearAllData 'THIS WILL CLEAR THE DATA
a = 0
For i = 0 To bufsize - 1
xlab(i) = "" & i
Next
lc1.XAxisLabels = xlab
lc1.DrawTheGraphs
lc1.START
End If
'************************ If you comment this code then the x-axis labels will be the index of the buffer
' xlabeltrack = xlabeltrack + 1
' If xlabeltrack > bufsize Then
' xlab = shiftarray(xlab)
' xlab(bufsize - 1) = "" & xlabeltrack
' lc1.XAxisLabels = xlab
' End If
' xlab(bufsize - 1) = "" & xlabeltrack
'**************************************************************************************************************
End Sub
Sub shiftarray (oldarray() As String) As String()
Dim newarray(bufsize)
For i = 0 To bufsize - 2
newarray(i) = oldarray(i + 1)
Next
Return newarray
End Sub
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