Maybe it's just me, but... On Monday, May 20, 2013 6:39:14 PM UTC+4, MagouyaWare wrote: > > > On Thu, May 16, 2013 at 3:14 AM, Miha <[email protected] > <javascript:>>wrote: > >> One possible solution I see is modifying the backing adapter >> implementation and providing a different view based on the state of the >> item, but that seems like wrong approach -- I would have to update the >> adapter with information on the selected item and call >> notifyDataSetChanged, which would (I suppose) result in an unnecessary >> re-drawing of the whole list. > > > Note though, that it doesn't redraw the ENTIRE list... just the items that > are visible on the screen. So, even if you have 500 items in your list, > you are only going to be redrawing the 10-20 items that are actually > visible to the user. I've used this approach before and it works quite > well. >
Implementing highlight through getView, and with a separate view type seems awfully backwards, since the framework already has mechanisms for doing almost all of it. A custom list item background should let the standard ListView item background show in certain states, e.g. first two states here: <?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android";> <item android:drawable="@android:color/transparent" android:state_pressed="true"/> <item android:drawable="@android:color/transparent" android:state_selected="true"/> <item android:drawable="@color/theme_light_message_list_checked" android:state_checked="true"/> <item android:drawable="@color/theme_light_message_list_read_background"/> </selector> Using ListView.drawSelectorOnTop=true would be even easier, but it can have some visual side effects (or not... depends on list item view... mine don't like this). The third state is what I use to implement "currently selected items" highlight on Android 2.1 - 4.2, by using setChecked on my item layouts. I chose this rather than state_activated, because the latter is API 11 and higher. public class AbsMessageListItemLayout extends RelativeLayout { public void setChecked(boolean isChecked) { if (mIsChecked != isChecked) { mIsChecked = isChecked; refreshDrawableState(); } } private static final int[] STATE_CHECKED = new int[] { android.R.attr.state_checked }; @Override protected int[] onCreateDrawableState(int extraSpace) { int[] baseState = super.onCreateDrawableState(extraSpace + 1); if (mIsChecked) { mergeDrawableStates(baseState, STATE_CHECKED); } return baseState; } } The final state in the above drawable is application specific (read/unread message indication), can be ignored... -- K > Thanks, > Justin Anderson > MagouyaWare Developer > http://sites.google.com/site/magouyaware > -- -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en --- You received this message because you are subscribed to the Google Groups "Android Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
