Android Question How to convert text to transparent bitmap

[toby]

I need some custom bitmaps to show the google map marker titles of all markers automatically without tapping. The created bitmap should just be large enough to show entire text.

I'm facing two problems with following code:
1. B4XCanvas expects a view which I can't provide; the created bitmaps will be shown as part of google map marker icons.
2. I couldn't make the bitmap's background transparent.

'''''''''''''''''''''''''''''''''''''''
Sub Globals
   Dim cvs As B4XCanvas    
   Private ImageView1 As ImageView
End Sub

sub CreateBitMap
    cvs.Initialize(ImageView1)
    Dim text As String="hello"
    Dim Fnt As B4XFont
    Fnt=xui.CreateDefaultFont(28)

    Dim centerX As Int=100
    Dim centerY As Int=60
    
    
    Dim r As B4XRect = cvs.MeasureText(text, Fnt)
    'ImageView1.Background=BackGround(Colors.Transparent) 'this line makes bitmap invisible
    ImageView1.Width=r.Width
    ImageView1.Height=r.Height
    Dim BaseLine As Int = centerY - r.Height / 2 - r.Top
    cvs.DrawText(text, centerX, BaseLine, Fnt, Colors.red, "CENTER")

   Dim bmp As Bitmap=cvs.CreateBitmap 
   'to do: code to save the created bitmap
end sub


Sub BackGround(Color As Int) As ColorDrawable
    Dim cdb As ColorDrawable

    cdb.Initialize(Color, 5dip)
    Return cdb
End Sub

A few threads in the forum mention "TextToBitmap" which might be what I need; unfortunately I couldn't find out which library it belongs to.

Could someone help me create a bitmap, from text, for use as google map marker icon, and/or locate "TextToBitmap" function/library, please?

TIA

 

[TILogistic]

B4X multiplatform:

this works better:

library XUI Views

    B4XImageView1.SetBitmap(TextToBitmap("Text to Bitmap", 20, xui.Color_Black, "CENTER"))
    B4XImageView1.mBackgroundColor = xui.Color_Transparent
    B4XImageView1.ResizeMode = "NONE"
    B4XImageView1.Update

Public Sub TextToBitmap (Text As String, FontSize As Float, FontColor As Int, TextAlignment As String) As B4XBitmap
    Dim xui As XUI
    Dim p As B4XView = xui.CreatePanel("")
    p.SetLayoutAnimated(0, 0, 0, 700dip, 700dip)
    Dim cvs1 As B4XCanvas
    cvs1.Initialize(p)
    Dim fnt As B4XFont = xui.CreateDefaultFont(FontSize)
    Dim r As B4XRect = cvs1.MeasureText(Text, fnt)
    Dim BaseLine As Int = cvs1.TargetRect.CenterY - r.Height / 2 - r.Top
    cvs1.DrawText(Text, cvs1.TargetRect.CenterX, BaseLine, fnt, FontColor, TextAlignment)
    Dim b As B4XBitmap = cvs1.CreateBitmap
    cvs1.Release
    Return b
End Sub

 

[TILogistic]

Test;

 

[TILogistic]

Some time ago, I made a text to bitmap subroutine for google maps, which you can also save to .png files.

Use this Post:

[B4X] [XUI] Accurate Text Measurement and Drawing

(It took me 7 years to get this one right.) XUI v1.60 includes a new method named B4XCanvas.MeasureText. This method accurately measures single line strings. It returns a B4XRect object with the width and height of the measured string. The Top field returns the highest point relative to...

www.b4x.com

Demo:

 

[TILogistic]

Check this out and it will give you an idea.

to create marker and information window

SuperToolTips

Hello, Could you tell me which way to use that kind of toolTips : seen on: https://stackoverflow.com/questions/21031488/android-popupwindow-with-tooltip-arrow Regards Michel

www.b4x.com

 

[TILogistic]

test:

b4xCanvas MeasureText (Multiline)

Is it posible to calculate the height of a label and text, but with multiple lines? The way that b4i SizeToFit works I think. Thanks FBP

www.b4x.com

 

[TILogistic]

see comments on this post:

Overlapping images + text, on Google Maps markers

I use jGoogleMaps to display a map and markers with the positions of some cars For each car I have a small image that is used to display the car on the map In addition to the position I would also like to indicate the direction of the individual cars and a text to indicate the speed and the...

www.b4x.com

 

[TILogistic]

I found the subroutine that I used in a project.

demo:

 

[AnandGupta]

WOW ! WOW !! oparra !!!

You gave so much help that now toby is spoilt for choice ! Even me

Regards,

Anand