Measuring MeasureStringHeight / Width ?

boten · Aug 20, 2011

I'm trying to display some text, as big as possible and centered vertically , in landscape mode, but I have some problems.
(never mind the width, the panel on which the text lies will eventually scroll)

I use Sub Measure to determine the biggest safe textsize, up to 3/4 of panel.height (using full panel.height
will only make things worse!)

The entire program follows, along with screen capture (on the emulator).

What am I doing wrong?

B4X:

Sub Process_Globals
End Sub

Sub Globals
Dim lbl As Label
Dim cvs As Canvas
Dim dum As Bitmap
Dim pnl As Panel
Dim phn As Phone
Dim tf As Typeface
End Sub

Sub Activity_Create(FirstTime As Boolean)
  
  tf=Typeface.CreateNew(Typeface.SERIF,Typeface.STYLE_NORMAL)
  
  pnl.Initialize("")
  activity.AddView(pnl,0,0,100%x,100%y)
  pnl.Color=Colors.White
  
  lbl.Initialize("")
  pnl.AddView(lbl,0,0,pnl.Width,pnl.Height)
  
  dum.InitializeMutable(60,60)
  cvs.Initialize2(dum)
  
End Sub

Sub Activity_Resume
Dim f,h,w As Int
Dim txt As String

 phn.SetScreenOrientation(0)  ' landsape only

  txt="Test"
  f=Measure(txt,tf)   ' find "max" text size to fit in panel's height
  
  w=cvs.MeasureStringWidth(txt,tf,f)
  h=cvs.MeasureStringHeight(txt,tf,f)
  pnl.Width=w  
  
  lbl.TextSize=f
  lbl.TextColor=Colors.Blue
  lbl.Typeface=tf
  lbl.Text=txt
  lbl.Width=w
  
  'lbl.Height=h  '<==== if active: This will REDUCE text even more
  lbl.Top=0

  activity.Title=f & "-" & pnl.Height & "-" & lbl.Height & " - " & h
End Sub

Sub Activity_Pause (UserClosed As Boolean)
End Sub

Sub Measure(Txt As String,Typ As Typeface) As Int
Dim h,t,p As Int
p=pnl.Height*3/4  ' using ALL of pnl.height will worsen situation
h=12
t=cvs.MeasureStringHeight(Txt,Typ,h)
Do While t<=p
  h=h+1
  t=cvs.MeasureStringHeight(Txt,Typ,h)
Loop
h=h-1
Return h
End Sub

Erel · Aug 20, 2011

You should set the label alignment to TOP. The simplest way to do it is with the visual designer.
Or:

B4X:

lbl.Gravity=Bit.Or(Gravity.TOP, Gravity.LEFT)

boten · Aug 20, 2011

Erel, Even tried to "push" the label way above the top of the panel:

B4X:

....
 h=cvs.MeasureStringHeight(txt,tf,f)
....
....

  lbl.Gravity=Gravity.TOP
  lbl.Top=-h/3

with the similar results. Looks like the actual drawing of the text leaves some (large) extra space above the letters, and also chops the bottom. Any ideas?

Erel · Aug 20, 2011

You can try drawing the text directly with Canvas.DrawText.

klaus · Aug 20, 2011

The code below works:

B4X:

[SIZE=2][FONT=Courier New][COLOR=#0000ff][SIZE=2][FONT=Courier New][COLOR=#0000ff][SIZE=2][FONT=Courier New][COLOR=#0000ff]Sub [/COLOR][/FONT][/SIZE][/COLOR][/FONT][/SIZE][/COLOR][/FONT][/SIZE][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]Globals[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] cvs [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Canvas[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] dum [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Bitmap[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] pnl [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Panel[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] phn [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Phone[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] tf [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Typeface[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] x0, x1 [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]End Sub[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
 
[FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Sub [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]Activity_Create(FirstTime [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Boolean[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2])[/SIZE][/FONT]
[SIZE=2][FONT=Courier New]  tf = [/FONT][/SIZE][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Typeface[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2].CreateNew([/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Typeface[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2].SERIF,[/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Typeface[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2].STYLE_NORMAL)[/SIZE][/FONT]
 
[SIZE=2][FONT=Courier New]  pnl.Initialize([/FONT][/SIZE][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800000][FONT=Courier New][SIZE=2][COLOR=#800000][FONT=Courier New][SIZE=2][COLOR=#800000]""[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2])[/SIZE][/FONT]
[SIZE=2][FONT=Courier New]  activity.AddView(pnl,[/FONT][/SIZE][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]0[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2],[/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]0[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2],[/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]100%x[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2],[/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]100%y[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2])[/SIZE][/FONT]
[SIZE=2][FONT=Courier New]  pnl.Color=[/FONT][/SIZE][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Colors[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2].White[/SIZE][/FONT]
 
[SIZE=2][FONT=Courier New]  cvs.Initialize(pnl)[/FONT][/SIZE]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]End Sub[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
 
[FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Sub [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]Activity_Resume[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] f,h,w [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] txt [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]String[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
[FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
[FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  phn.SetScreenOrientation([/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]0[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]) [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008000][FONT=Courier New][SIZE=2][COLOR=#008000][FONT=Courier New][SIZE=2][COLOR=#008000]' landsape only[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  txt = [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800000][FONT=Courier New][SIZE=2][COLOR=#800000][FONT=Courier New][SIZE=2][COLOR=#800000]"Test"[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  f = Measure(txt,tf) [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008000][FONT=Courier New][SIZE=2][COLOR=#008000][FONT=Courier New][SIZE=2][COLOR=#008000]' find "max" text size to fit in panel's height[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
[SIZE=2][FONT=Courier New][SIZE=2][FONT=Courier New]  w = cvs.MeasureStringWidth(txt,tf,f)[/FONT][/SIZE]
[SIZE=2][FONT=Courier New]  h = cvs.MeasureStringHeight(txt,tf,f)[/FONT][/SIZE]
[SIZE=2][FONT=Courier New]  pnl.Width = w[/FONT][/SIZE]
 
[SIZE=2][FONT=Courier New]  cvs.Initialize(pnl) [/FONT][/SIZE][/FONT][/SIZE][FONT=Courier New][SIZE=2][COLOR=#008000][FONT=Courier New][SIZE=2][COLOR=#008000][FONT=Courier New][SIZE=2][COLOR=#008000]' needed to adapt the canvas to the new dimensions[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  cvs.DrawText(txt, [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]0.5[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] * pnl.Width, (pnl.Height + h)/[/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]2[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2], tf, f, [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Colors[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2].Blue, [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800000][FONT=Courier New][SIZE=2][COLOR=#800000][FONT=Courier New][SIZE=2][COLOR=#800000]"CENTER"[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2])[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]End Sub[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
 
[FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Sub [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]Activity_Touch (Action [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Int[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2], X [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2], Y [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2])[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] x2 [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
[FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT] 
[FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Select[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] Action[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Case[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] Activity.ACTION_DOWN[/SIZE][/FONT]
[SIZE=2][FONT=Courier New]    x0 = pnl.Left[/FONT][/SIZE]
[SIZE=2][FONT=Courier New]    x1 = X[/FONT][/SIZE]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Case[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] Activity.ACTION_MOVE[/SIZE][/FONT]
[SIZE=2][FONT=Courier New]    x2 = X - x1[/FONT][/SIZE]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]    If[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] x2 > [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]0 [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]      x2 = [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]0[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]    Else [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] x2 < -(pnl.Width - [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]100%x[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]) [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Then[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]      x2 = -(pnl.Width - [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]100%x[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2])[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]    End [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]If[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  End [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Select[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  pnl.Left = x2[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]End Sub[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
 
[FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Sub [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]Measure(Txt [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]String[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2],Typ [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]Typeface[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]) [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Dim[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] h,t,p [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][COLOR=#008b8b]Float[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
[FONT=Courier New][SIZE=2][COLOR=#008b8b][FONT=Courier New][SIZE=2][/SIZE][/FONT][/COLOR][/SIZE][/FONT]
[SIZE=2][FONT=Courier New][SIZE=2][FONT=Courier New]  p = pnl.Height * [/FONT][/SIZE][/FONT][/SIZE][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]3[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]/[/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]4[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  h = [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]12[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  t = cvs.MeasureStringHeight(Txt,Typ,h)[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Do [/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]While[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] t <= p[/SIZE][/FONT]
[SIZE=2][FONT=Courier New]    h = h + [/FONT][/SIZE][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]1[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]    t = cvs.MeasureStringHeight(Txt,Typ,h)[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Loop[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2]  h = h - [/SIZE][/FONT][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080][FONT=Courier New][SIZE=2][COLOR=#800080]1[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]  Return[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Courier New][SIZE=2][FONT=Courier New][SIZE=2] h[/SIZE][/FONT]
[/SIZE][/FONT][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff][FONT=Courier New][SIZE=2][COLOR=#0000ff]End Sub[/COLOR][/SIZE][/FONT]
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT]

Best regards.

boten · Aug 20, 2011

Since the Label view did not behave as I thought it should be (height & top "issues") I tried your advice of using DrawText directly on the panel. Two observations:

1) the y position of the drawtext refers to the BOTTOM of the text (and not the "natural" top!) - Took me some frustrated minutes to find that out (Klaus used this in his code above..)

2) I got huge text size, seems that the panel was streched to make the text wider. I even tried getting the measures with one canvas (on a dummy mutable bitmap) and the using a second canvas and redefine its width. And then I saw Klaus's reply. The key stmt is of course:

B4X:

cvs.Initialize(pnl) ' needed to adapt the canvas to the new dimensions

but since I lack any artistic qualities, a canvas pauses some mistery to me . Luckily, Klaus will always have a solution to drawing problems.
Thanks!

boten · Aug 20, 2011

But now there's another problem:

The Sub where the canvas is re-adjusted to the new panel's width is called again and again (setting different parms which must cause the panel to be "re-computed" like changing font, textcolor, size of text, etc....)

and in doing so, the stmt:

B4X:

cvs.Initialize(pnl)

is causing error. Looks like memory error:

B4X:

14708784-byte external allocation too large for this process.
VM won't let us allocate 14708784 bytes
Shutting down VM
threadid=1: thread exiting with uncaught exception (group=0x4001d800)
FATAL EXCEPTION: main


java.lang.OutOfMemoryError: bitmap size exceeds VM budget
   at android.graphics.Bitmap.nativeCreate(Native Method)
   at android.graphics.Bitmap.createBitmap(Bitmap.java:468)
   at anywheresoftware.b4a.objects.drawable.CanvasWrapper.Initialize(CanvasWrapper.java:71)
   at boten.aaa.main._start(main.java:2001)
   at boten.aaa.main._activity_resume(main.java:628)

maybe it's just the emulator's assigned memory, but isn't there some garbage collection to deal with reinitializing a canvas to a view?

klaus · Aug 20, 2011

How often do you call the drawing onto the Panel?

Best regards.

boten · Aug 20, 2011

VERY often!
Every time a menu item is selected, the menu panel (scrollview, or just an about panel) is shown in portrait. The drawing is done in landscape. So I change frequntrly between portarit (menus) and landscape (drawing). Every time orientation is changed (by code) Activity_Create and Activity_Resume are called. I call the drawing routine in Activity_Resume.

klaus · Aug 20, 2011

I just tried my test program, the code I posted, in the Emulator.
I changed about 30 times the orientation without any problem.

Sorry, but I don't know what the problem is.

Best regards.

boten · Aug 20, 2011

Strangly, it happens on the emulator sized 800x480 but not on emulator sized 320x240.

Erel · Aug 20, 2011

You are using a much larger panel on the higher resolution emulator.
There is no reason to call canvas.initialize more than once. Each time you call it you are creating a new bitmap.

boten · Aug 20, 2011

Then how would I increase the size of the panel to accomodate for a different font size?

agraham · Aug 20, 2011

I think it's the classic "large native allocated bitmap is wrapped by a small managed bitmap wrapper and so the VM garbage collector is not collecting the wrapper because it doesn't think it's out of memory yet while the native heap is exhausted" problem. The fact that the larger display causes the problem while the smaller doesn't does tend to confirm this.

My PageTurnView library has a RecycleBitmap function you could use to try freeing a bitmap when you know you don't need it or it's trivial to do it with my Reflection library.

B4X:

   Dim Obj1 As Reflector
   Obj1.Target = bmp ' bmp is the unwanted Bitmap
   Obj1.RunMethod("recycle")

boten · Aug 20, 2011

I'll try that, but can the target be the canvas?

edit:
Nope. Tried

B4X:

 Dim Obj1 As Reflector
   Obj1.Target = cvs.Bitmap 'bmp ' bmp is the unwanted Bitmap
   Obj1.RunMethod("recycle")
   
  Log("---about to init canvas again---- " & pnl.Width)
  cvs.Initialize(pnl)  ' **** re-adjust canvas to panel size !!!!!

same error "canvaswrapper...."

I think I'll go back to label view, although it behaves "strangely" with very big font sizes, as per my earlier posts on this thread.

agraham · Aug 20, 2011

No. You can get the bitmap from a canvas but note that if the canvas is initialised on a view you will need to give that view another drawable or initialize a canvas on it before it is drawn again or you will get a "Canvas: trying to use a recycled bitmap " exception and your app will force close.

B4X:

   Obj1.Target = canv
   Obj1.Target = Obj1.GetField("bw")
   Obj1.Target = Obj1.RunMethod("getObject")
   Obj1.RunMethod("recycle")

Erel · Aug 20, 2011

Then how would I increase the size of the panel to accomodate for a different font size?

Why not set the panel to its maximum possible size?

You can also create a large mutable bitmap and assign it as the panel background (using a BitmapDrawable). This will allow you to reuse the bitmap.

boten · Aug 20, 2011

agraham said:

B4X:

   Obj1.Target = canv
   Obj1.Target = Obj1.GetField("bw")
   Obj1.Target = Obj1.RunMethod("getObject")
   Obj1.RunMethod("recycle")

Sorry agraham, that didn't help either.

B4X:

pnl.Width=w  ' computed from MeasureStringWidth

Dim Obj1 As Reflector
  Obj1.Target = cvs
  Obj1.Target = Obj1.GetField("bw")
  Obj1.Target = Obj1.RunMethod("getObject")
  Obj1.RunMethod("recycle")
   
 Log("about to init canvas " & pnl.Width) ' pnl.Width=4124
  cvs.Initialize(pnl)  ' **** re-adjust canvas to panel size 
  Log("OK canvas again")

boten · Aug 20, 2011

Erel said:
Why not set the panel to its maximum possible size?

The string to be displayed will vary by length (input from user) . Also the MesureStringHeight will be different for "aaa" than for "fyhgtj" even with same fontsize, because of the "ups and downs" of the letters like j & f, not to mention that MesureStringWidth will be different for "iii" than for "WWW"

Erel · Aug 20, 2011

This doesn't mean that you need to resize the panel. Just clear it and draw the text again.

Measuring MeasureStringHeight / Width ?

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