Android Tutorial Load HTML to Label

Brandsum

Well-Known Member
Licensed User
(Here is the iOS version)
This is how you can set HTML data to Label (works only in release mode),

Dependencies: StringUtils, jSoup, LabelExtras

Here is the code,
B4X:
Dim extraHeight As Int = 0 'global variable (height of images)
Dim htmlParser As Html 'global variable
Dim jSoup As jSoup 'global variable
Dim htmlLabel As Label 'global variable
Dim strUtils As StringUtils 'global variable

Dim HtmlString = "YOUT HTML STRING"
Dim HtmlImgList As List = jSoup.selectorElementAttr(HtmlString,"img","src") 'list all the images to be downloaded

'HtmlViewImgDownloader is a replica of Erel's ImageDownloader class. But it just stores the downloaded image to cache folder of app
Dim rs As ResumableSub = CallSub2(HtmlViewImgDownloader,"Download",HtmlImgList)
Wait For (rs) Complete (result As Boolean)

htmlLabel.Initialize("")
htmlLabel.Text = htmlParser.FromHtml2(HtmlString,"ImageGetter","TagGetter")
htmlLabel.TextSize = 16
htmlLabel.width = 100%x
htmlLabel.height = strUtils.MeasureMultilineTextHeight(htmlLabel,htmlLabel.Text.Trim) + extraHeight


'It handles image tags while parsing your html string
Sub ImageGetter_GetDrawable(Source As String) As Object
    Source = Regex.Split("/",Source)(Regex.Split("/",Source).Length-1) 'get image name from source string
    If File.Exists(File.DirDefaultExternal &"/cache", Source) Then
        Dim Bitmap1 As Bitmap
        Bitmap1=LoadBitmap(File.DirDefaultExternal &"/cache", Source)
    
        Dim BitmapDrawable1 As BitmapDrawable
        BitmapDrawable1.Initialize(Bitmap1)
  
        Dim l As LabelExtras
        l.SetDrawableBounds(BitmapDrawable1, 0, 0, 100%x, 100%x * (Bitmap1.Height/Bitmap1.Width))
        extraHeight = extraHeight + 100%x * (Bitmap1.Height/Bitmap1.Width)
        Return BitmapDrawable1
    Else
        Return Null
    End If
End Sub
Here is the image downloader service module code save it as "HtmlViewImgDownloader",
B4X:
#Region  Service Attributes
    #StartAtBoot: False
#End Region

Sub Process_Globals
    Private ongoingTasks As Map
End Sub

Sub Service_Create
    ongoingTasks.Initialize
End Sub

Sub Service_Start (StartingIntent As Intent)
    Service.StopAutomaticForeground 'Call this when the background task completes (if there is one)
End Sub

Sub Service_Destroy

End Sub

Sub Download (ImageSource As List) As ResumableSub
    For i = 0 To ImageSource.Size - 1
        Dim link As String = ImageSource.get(i)
        If ongoingTasks.ContainsKey(link) = False Then
            ongoingTasks.Put(link, "")
            Dim imgName As String = Regex.Split("/",link)(Regex.Split("/",link).Length-1)
            If File.Exists(File.DirDefaultExternal & "/cache",imgName) And File.Size(File.DirDefaultExternal & "/cache",imgName)>0 Then
                Try
                    ' check if image file is corrupted or not
                    Dim x As Bitmap 'ignore
                    x = LoadBitmapResize(File.DirDefaultExternal& "/cache",imgName,50dip,50dip,True)
                    ongoingTasks.Remove(link)
                Catch
                    Dim j As HttpJob
                    j.Initialize(link, Me)
                    j.Download(link)
                    wait For (j) JobDone(j As HttpJob)
                    If j.Success Then
                        Dim bmp As B4XBitmap = j.GetBitmap
                        Dim os As OutputStream
                        os = File.OpenOutput(File.DirDefaultExternal & "/cache",imgName,False)
                        If imgName.ToLowerCase.EndsWith(".png") Then
                            bmp.WriteToStream(os,100,"PNG")
                        Else
                            bmp.WriteToStream(os,100,"JPEG")
                        End If
                        os.Close
                        ongoingTasks.Remove(j.JobName)
                    End If
                    j.Release
                End Try
            Else
                Dim j As HttpJob
                j.Initialize(link, Me)
                j.Download(link)
                wait For (j) JobDone(j As HttpJob)
                If j.Success Then
                    Dim bmp As B4XBitmap = j.GetBitmap
                    Dim os As OutputStream
                    os = File.OpenOutput(File.DirDefaultExternal & "/cache",imgName,False)
                    If imgName.ToLowerCase.EndsWith(".png") Then
                        bmp.WriteToStream(os,100,"PNG")
                    Else
                        bmp.WriteToStream(os,100,"JPEG")
                    End If
                    os.Close
                    ongoingTasks.Remove(j.JobName)
                End If
                j.Release
            End If
        End If
    Next
    Return True
End Sub

Sub ActivityIsPaused
    ongoingTasks.Clear
End Sub
Happy Coding :)
 
Last edited:
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