andlabs-ui/wintable/update.h

45 lines
1.8 KiB
C

// 8 january 2015
// Whenever a number of things in the Table changes, the update() function needs to be called to update any metrics and scrolling positions.
// The control font changing is the big one, as that comes with a flag that decides whether or not to redraw everything. We'll need to respect that here.
// TODO actually use redraw here
static void update(struct table *t, BOOL redraw)
{
RECT client;
intptr_t i;
intptr_t height;
// before we do anything we need the client rect
if (GetClientRect(t->hwnd, &client) == 0)
panic("error getting Table client rect in update()");
// the first step is to figure out how wide the whole table is
// TODO count dividers?
t->width = 0;
for (i = 0; i < t->nColumns; i++)
t->width += columnWidth(t, i);
// now we need to figure out how much of the width of the table can be seen at once
t->hpagesize = client.right - client.left;
// this part is critical: if we resize the columns to less than the client area width, then the following hscrollby() will make t->hscrollpos negative, which does very bad things
// we do this regardless of which of the two has changed, just to be safe
if (t->hpagesize > t->width)
t->hpagesize = t->width;
// now we do a dummy horizontal scroll to apply the new width and horizontal page size
// this will also reposition and resize the header (the latter in case the font changed), which will be important for the next step
hscrollby(t, 0);
// now that we have the new height of the header, we can fix up vertical scrolling
// so let's take the header height away from the client area
client.top += t->headerHeight;
// and update our page size appropriately
height = client.bottom - client.top;
t->vpagesize = height / rowht(t);
// and do a dummy vertical scroll to apply that
vscrollby(t, 0);
// TODO invalidate /everything/?
}