TScrollBar TRect issue

[jordiperezartigues]

This is the TRect i pass to the TListBox constructor, listBox = new TListBox(rectListBox,1,vScrollBar);
TRect rectScrollBar(42, 4, 43, 7);

rectScrollBar.b.y is 7, it shall be 22, and grows a lot when 8 or 10.

What is happening to adjust correctly the TScrollBar to the TListBox?

[magiblot]

Can you share more code? For example, the whole initialization code of your dialog? (except for the TListBox items)

[jordiperezartigues]

TInputLine *editLine = new TInputLine(TRect(maxLengthLabel+4, y, maxLengthLabel+ithem->length+6, y+1),  ithem->length+1);
this->dlg->insert(editLine);

TListBox            *listBox;
TScrollBar         *vScrollBar;
TRect                 rectListBox(maxLengthLabel+4,y,maxLengthLabel + ithem->length+5,y+22 );
TRect                 rectScrollBar(maxLengthLabel + ithem->length+4,y, maxLengthLabel + ithem->length+5,7);

vScrollBar = new TScrollBar(rectScrollBar);
listBox = new TListBox(rectListBox,1,vScrollBar);

            for (ushort i = 0; i < numRows; i++)
            {
                llistaRegs->atInsert(i, newStr(valueLista[i]));
            }
            listBox->newList(llistaRegs);

this->dlg->insert(vScrollBar);
this->dlg->insert(listBox);

[magiblot]

Wouldn't it be simpler to do the following?

TRect rectScrollBar(rectListBox.b.x, rectListBox.a.y, rectListBox.b.x + 1, rectListBox.b.y);

[jordiperezartigues]

yes, this initializes the TRect cleaner.

but the scrollbar keeps growing to much

[magiblot]

I'm sorry, but I am unable to find the cause of this unexpected behaviour just by looking at the code. I could try to create an application that replicates the way you initialize the dialog, but since I'm not sure this is a bug in the Turbo Vision library I don't want to spend time trying to reproduce this issue in vain.

If you could please share the complete source code of a sample application that has just this dialog and reproduces this issue, I would be able to run it with a debugger and quickly find out what's wrong.

[jordiperezartigues]

TurboVisionTest.zip

I atach the code.

The form i was showing is under the menu: llistaEntities->AddEntitie

[magiblot]

Okay. This problem occurs because you use the growTo() function to resize the dialog to its final size, after inserting all the controls.

Unlike other views, TScrollBar has a default growMode that suits the behaviour of a scrollbar that is placed on the right or bottom window margin:

tvision/source/tvision/tscrlbar.cpp

Lines 47 to 56 in 85aaeca

	if( size.x == 1 )
	{
	growMode = gfGrowLoX | gfGrowHiX | gfGrowHiY;
	memcpy( chars, vChars, sizeof(vChars) );
	}
	else
	{
	growMode = gfGrowLoY | gfGrowHiX | gfGrowHiY;
	memcpy( chars, hChars, sizeof(hChars) );
	}

This means that calling growTo() causes the scroll bar to enlarge, regardless of the initial height you specified for it.

The solution is to set an appropiate growMode for your scrollbar. In this case we use 0, which is the same as the other views you are using in the dialog (since it's the default value set in TView's constructor):

--- a/TurboVisionTest/formeditable.cpp
+++ b/TurboVisionTest/formeditable.cpp
@@ -86,6 +86,7 @@ void FormEditable::buildForm(FieldsDlg reg, const char *title)
            // listBox = new TListBox(TRect(maxLengthLabel+4, y, UIlx-3,std::min(y+numRows,desktopLy-8)),2,0);
 
             vScrollBar = new TScrollBar(rectScrollBar);
+            vScrollBar->growMode = 0; // Do not allow the TScrollBar to be enlarged by 'growTo()'.
 
 
             listBox = new TListBox(rectListBox,1,vScrollBar);

Besides this, you should consider using the strwidth() function to measure text width instead of ithem->labeltext.length(), which relies just on the number of bytes:

--- a/TurboVisionTest/formeditable.cpp
+++ b/TurboVisionTest/formeditable.cpp
@@ -35,7 +35,7 @@ void FormEditable::buildForm(FieldsDlg reg, const char *title)
     //get max lengths
     for (const FormArgs *ithem:reg)
     {
-        maxLengthLabel = std::max(maxLengthLabel, (ushort)ithem->labeltext.length());
+        maxLengthLabel = std::max(maxLengthLabel, (ushort)strwidth(ithem->labeltext));
         maxLengthInputLine = std::max(maxLengthInputLine, (ushort)ithem->length);
     }
     const ushort UIlx = maxLengthLabel + maxLengthInputLine + 9;
@@ -46,7 +46,7 @@ void FormEditable::buildForm(FieldsDlg reg, const char *title)
 
     for (FormArgs *ithem:reg)
     {
-        TStaticText *label = new TStaticText(TRect(maxLengthLabel + 2 - ithem->labeltext.length(), y,
+        TStaticText *label = new TStaticText(TRect(maxLengthLabel + 2 - strwidth(ithem->labeltext), y,
                                                    maxLengthLabel + 2, y+1), ithem->labeltext);
 
         this->dlg->insert(label);

[jordiperezartigues]

Thanks to you, setting the growmode to zero on the scrollbar makes it work.