Android Question [SOLVED] How to create a pdf table using the Printer library?

[noeleon]

Hello.
How can I create a table in a pdf using the Printer library?
A simple drawText won't do because the "cells" may contain long text and must not overlap each other.
I had a project years ago where I drew each cell to a label and used its snapshot, which is a bitmap, to assemble a table.
I really need the texts to be selectable.
Thanks.

 

[noeleon]

I attached a sample project.
The label is drawn to the pdf and is selectable but I don't know how to set its coordinates, it is at the top left corner of the page

 

[noeleon]

I think what I should do is to use canvas.drawpath and reduce the font size to fit the text to a cell

 

[emexes]

Did/would you consider using PDF Generator - B4X Cross Platform - Class 100% B4X Code ?

The documentation indicates it has methods that:

• draw text : single line of text at position x, y
• Measure text (width and height)
• draw line
• draw rectangle

which sound like all the essentials needed to create your PDF table.

 

[noeleon]

Did/would you consider using PDF Generator - B4X Cross Platform - Class 100% B4X Code ?

The documentation indicates it has methods that:

• draw text : single line of text at position x, y
• Measure text (width and height)
• draw line
• draw rectangle

which sound like all the essentials needed to create your PDF table.

I tried that but I find it very confusing. The y coordinate starts at the bottom. For example, the coordinates 20,30 is 20 from left and 30 from the bottom. So when I write text like a number per line in a loop it would appear on the page as
3
2
1
But when I copy the text and paste it somewhere it is
1
2
3

 

[emexes]

The y coordinate starts at the bottom.

Yeah, I agree that doesn't help. I wrote a function to flip Y coordinates so that they are from the top:

Sub FlipY(Y As Float) As Float
    Return 297 - Y
End Sub

and then this routine to create a PDF from a supplied 2D String Array:

Private Sub PrintTable(NumRows As Int, NumCols As Int, Tbl(,) As String, X As Int, Y As Int, W As Int, H As Int)
    Dim pdf As cPDF
    pdf.Initialize("mm")
    
    pdf.pageAdd(pdf.pageSizeA4PortraitWidth, pdf.pageSizeA4PortraitHeight)

    pdf.sFont( _
        pdf.fontHelvetica, _
        pdf.fontBold, _
        12, _
        pdf.colorBlack _
    )
    
    Dim RowY(NumRows + 1) As Float
    For R = 0 To NumRows
        RowY(R) = Y + R / NumRows * H
        Log(R & TAB & RowY(R))
    Next
    
    Dim ColX(NumCols + 1) As Float
    For C = 0 To NumCols
        ColX(C) = X + C / NumCols * W
        Log(C & TAB & ColX(C))
    Next
    
    ColX(1) = ColX(1) - 10    'demo individual column widths

    'draw table grid
    For R = 0 To NumRows
        pdf.outLine(ColX(0), FlipY(RowY(R)), ColX(NumCols), FlipY(RowY(R)))
    Next
    For C = 0 To NumCols
        pdf.outLine(ColX(C), FlipY(RowY(0)), ColX(C), FlipY(RowY(NumRows)))
    Next

    'draw table contents
    For R = 0 To NumRows - 1
        For C = 0 To NumCols - 1
            pdf.outtext(ColX(C) + 2.0, FlipY(RowY(R) + 5.0), Tbl(R, C))
        Next
    Next
    
    'save to file with compression if data compressed are smaller
    savePDF(pdf,"test.pdf",pdf.CompressAlways)
    
    'open with default viewer
    openPDF("test.pdf")
End Sub

which, when tested with:

Dim NumRows As Int = 38
Dim NumCols As Int = 3

Dim Tbl(NumRows, NumCols) As String

For R = 0 To NumRows - 1
    For C = 0 To NumCols - 1
        Tbl(R, C) = "row " & (R + 1) & " col " & (C + 1)
        If C = 1 Then
            Tbl(R, C) = Tbl(R, C) & " " & "RandomWordString".SubString(Rnd(0, 17))
        End If
    Next
Next

PrintTable(NumRows, NumCols, Tbl, 20, 20, 180, 260)

produced the attached PDF file:

 

[noeleon]

I wrote a function to flip Y coordinates so that they are from the top:

Thank you @emexes for trying to help but for now I will have to stick to the Printing library because I also want to use a custom font.

I wonder if that's possible with the outRAW function. The documentation says it can do a lot more including creating a proper table. I hope spsp can bring more features to his library.

 

[emexes]

How can I create a table in a pdf using the Printer library?

Just to clarify:

the Printing library has two ways of generating output:

PdfDocument
Printer

Which do you wish to use?

PdfDocument's line and text drawing methods look like they'll do the job:

dim pdf as PdfDocument
pdf.Initialize
pdf.StartPage(595, 842) 'A4 size
pdf.Canvas.DrawLine(2, 2, 593 , 840, Colors.Blue, 4)
pdf.Canvas.DrawText("Hello", 100, 100, Typeface.DEFAULT_BOLD, 30, Colors.Yellow, "CENTER")
pdf.FinishPage

 

[emexes]

Lol look what I just stumbled across whilst trying to work out if I could use the (B4A?) Printing library in B4J:

https://www.b4x.com/android/forum/threads/best-way-to-print-from-b4j.119251/#post-745809

(not quite sure why I called Mike Brian, but I'm sure there was a reason )

 

[noeleon]

Which do you wish to use?

the PdfDocument

 

[noeleon]

I think I finally got it. Just need to adjust the text sizes to fit long text

 

[emexes]

Just need to adjust the text sizes to fit long text

My only suggestion of consequence so far is to close the rectangle:

Sub drawRectangle(left As Int, top As Int, width As Int, height As Int)
    Path.Initialize(left, top)
    Path.LineTo(left, top+height)
    Path.LineTo(left+width, top+height)
    Path.LineTo(left+width, top)
    Path.LineTo(left, top)
    CV.DrawPath(Path, Colors.Black, False, 0.2)
End Sub

unless... is there a reason for having no border at the top of the table?

 

[emexes]

Maybe do the cell drawing inside a loop rather than repeat it three times:

Sub createCellsRow(Texts() As String, Left As Double, Top As Double, Widths() As Double, Height As Double)
    Dim FirstCol As Int = 0    'should really be parameters
    Dim LastCol As Int = 2
    
    For Col = FirstCol To LastCol
        drawRectangle(Left, Top, Widths(Col), Height)
        CV.ClipPath(Path)
        CV.DrawText(Texts(Col), Left+1, Top + Height - 4, Typeface.DEFAULT, 5, Colors.Black, "LEFT")
        CV.RemoveClip
        Left = Left + Widths(Col)    'final column easier to do than to skip (might even be useful in future)
    Next
End Sub

 

[noeleon]

unless... is there a reason for having no border at the top of the table?

none at all. I must have accidentally deleted a line

 

[emexes]

Is your table wider than one page, as in split across pages horizontally?

Split across pages vertically isn't so bad, but split both vertically and horizontally, that's a more interesting challenge.

 

[noeleon]

Is your table wider than one page, as in split across pages horizontally?

Split across pages vertically isn't so bad, but split both vertically and horizontally, that's a more interesting challenge.

No. My table has about 20k rows. The cells are a little wider than my example but it would continue to the middle of the page then to the right side, and then to the next page. It would take 100 pages more or less.

 

[emexes]

My table has about 20k rows.

That's a lot of rows.

It would take 100 pages more or less.

20000 rows / (11 inches x 8 lines/inch) = 228 pages

without taking into account margins and headings

good thing it's a pdf and not on paper

although... if it's not on paper, perhaps HTML might be more useable, eg can import directly into a spreadsheet no problem

or is there some auditability or archivability requirement?

---

ps a local computer supplier here used to print pricelists like this:

https://docplayer.net/storage/101/151430833/1706428419/zDs6SFk5PioO6IgMaDBAUg/151430833.pdf

which were bordering on unusable even before my eyesight dropped to 6/6.

 

[noeleon]

20000 rows / (11 inches x 8 lines/inch) = 228 pages

20,000 / (38 * 3) = 175

 

[noeleon]

if it's not on paper

my users are gonna print it. Paper and ink don't seem to be an issue to them