In normal programs this isn't directly possible either; the listview control (in report mode) simply doesn't directly support this.
However, it is always done by displaying an editbox control (or combobox control or whatever else is needed as 'input' control) over the field you want to edit and filling this editbox with the value of the field. After you've done editing the editbox control is removed (hidden).
But as you can guess this requires some calls to the listview to get the exact column and row position (to be able to know where to display the editbox), and some callbacks.
The stuff you need for this isn't completely supported by Plus!, unfortunatly. There are some workarounds, but they are dodgy and have other disadvantages/shortcommings.
It would be very cool if Patchou could make it directly supported in Plus! of course. Even just adding the ability to use proper callbacks would solve it from what I remember from my trials with this (but then you still need to do the job yourself of course; but it would make it possible).
PS: in the mean time you can always use the listview to display your stuff, and for editing it make a (fixed) row of several editboxes below the listview. Each time the user clicks on a field in the listview, the row of editboxes is filled with the values of that listview row. And the user can then edit the values it in that way.
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EDIT: Vikke's suggestion is exactly the same as mine. The only difference is that his suggestion involves an extra window, whereas I said you can add it below your listview in the very same window (=more user friendly IMHO):
+-------+-------+-------+-------+-------+
| title1| title2| title3| title4| title5| <== listview control
+-------+-------+-------+-------+-------+
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
+-------+-------+-------+-------+-------+
.+-----+ +-----+ +-----+ +-----+ +-----+.
.| | | | | | | | | |. <== editboxes, one per column
.+-----+ +-----+ +-----+ +-----+ +-----+.
When the user highlights a line in the listview, the cells are filled in in the editbox. When the user clicks in an editbox the row in the listview stays highlighted (this is a property of the listview which you can set) and he can edit the value. As soon as the focus is lost from a specific editbox, that value is copied back to the proper cell in the listview. In this way: no need for an extra window with the same labels, more buttons, etc. It enables quicker editing (if that is what you want of course).
It is just a matter of design, of where to place the editboxes. The method is exactly the same: using a row of editboxes. In both cases you don't need any scrollbars though. PS: you can move controls on windows on the fly. This means that you can even make your editboxes grow or shrink according to the column widths of the listview in case you have dynamic column widths.
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