draw large image on screen and scroll

[vinaykk]

Hi All,

i want to load an image larger than screen resolution(360x640)(nokia 5800) and need to scroll that image to view all parts of image. after that i want to draw something on that image and store back. can anybody help me in this regard.
drawing and saving image is ready, only scrolling and editing is needed.

Thanks in advance,
Vinay.

[kkrish]

Hi,

Check the link migth be helpful to you.

[wizard_hu_]

If you have the image in the memory, a simple "BitBlt(const TPoint &aPoint, const CFbsBitmap *aBitmap, const TRect &aSourceRect)" can scroll it to you: fix aPoint to 0,0, and specify aSourceRect moving aroung in your bitmap.

[vinaykk]

kkrish
u mean i hav to scale image to screen resoluition draw on it and rescale to original size and save?

wizard
can u please explain in detail
now im drawing image by bitblt(tpoint, cfbsbitmap)
furhter wht i need to do achieve scrolling?

[wizard_hu_]

Depending on how it works internally, the simple BitBlt(TPoint,CFbsBitmap) can be efficient too.
Anyway, you obviously need something which triggers scrolling, either modify coordinates and issue DrawNow in your OfferKeyEventL, or use a timer (if you want it to be automatic).

[vinaykk]

im working in S60 5th edition.
Can we create one scrollable container and draw image in that?
any api for creating scrollable container?

[mayankkedia]

Yes you can, try the wiki link below :-

http://wiki.forum.nokia.com/index.ph...ol:_Scrollbars

http://wiki.forum.nokia.com/index.ph...able_Container

[vinaykk]

i tried first link, but scrollbars are not visible.
just adding CEikScrollBarFrame instance in Container::ConstructL()
is enought to get scrollbars?
scrollbars can be visible in container of no controls?

[vinaykk]

by using these lines of code i got horizontal n vertical scrolls in container

iScrollBarFrame = new ( ELeave ) CEikScrollBarFrame( this, this, ETrue );
iScrollBarFrame->CreateDoubleSpanScrollBarsL( ETrue, EFalse );
iScrollBarFrame->SetTypeOfVScrollBar( CEikScrollBarFrame::EDoubleSpan );
iScrollBarFrame->SetScrollBarVisibilityL( CEikScrollBarFrame::EOn,
CEikScrollBarFrame::EOn );
iVDsSbarModel.SetScrollSpan(4);
iVDsSbarModel.SetWindowSize(1);
iVDsSbarModel.SetFocusPosition(0);

iHDsSbarModel.SetScrollSpan(3);
iHDsSbarModel.SetWindowSize(1);
iHDsSbarModel.SetFocusPosition(0);

TEikScrollBarFrameLayout layout;
layout.iTilingMode = TEikScrollBarFrameLayout::EInclusiveRectConstant;
TRect rect = Rect();
iScrollBarFrame->TileL(&iHDsSbarModel,&iVDsSbarModel,rect,rect,layout);
iScrollBarFrame->SetVFocusPosToThumbPos(iVDsSbarModel.FocusPosition());

[gangadhar.bonda]

Hai ,
If you want to draw a large image do the following.
i) Divide the image into some parts
ii) a) For suppose the size of image is 700 units.
b) Divide the image by some constant units i.e by amount you want to scroll for suppose by 20 units
c) Now you will get the number of parts you can scroll i.e 700/20+ 700%20 (reminder part if anything is left).
d) Then assign the values to the scroll bar based on your requirement.
e) You can create an impression to the user that you are scrolling by moving the image to negative y-axis.
f) Initially you can draw the image to particular height i.e 600 units from TPoint(0,0)
So you draw the image to that height using DrawBitmap and you will show only few parts for suppose 30.
Now when you scroll down you want to remove the first part and show the 31st part. To show this draw the image from TPoint(0,-20) i.e negative y-axis so that the first part wont be visible and the 31st part will be visible.
Similarly to show 32nd part move the drawing co-ordinate to TPoint(0,-40).

In this way you can draw a large image. Please let me know for any concerns.