Using Views with Pickers
Picker views use a basic view-reuse scheme, caching the views supplied to it for possible reuse. When the final parameter for the pickerView:viewForRow:forComponent:reusingView:
method is not nil
, you can reuse the passed view by updating its settings or contents. Check for the view and allocate a new one only if one has not been supplied.
The height need not match the actual view. Implement pickerView:rowHeightForComponent:
to set the row height used by each component. Recipe 9-8 uses a row height of 120 points, providing plenty of room for each image and laying the groundwork for the illusion that the picker could be continuous rather than having a starting point and an ending point.
Notice the high number of components: ...
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