ListView fast scrolling error
I am working on a dictionary app. I have a list with fast scrolling support and an adapter that implements SectionIndexer. When I work with a Chinese dictionary I have a lot more sections, then when you work with Western European languages and have a little problem:
if i stop fast scrolling and while the scrollbars are visible, start using the default scrolling of my "fast scroll scroll" to another position (somewhere at the top) and only when i get almost at the end of the list will it start to move to my higher position too speed.
Is there a reason for this behavior? If there is a way to hide the fast scrollbars when using the default scrolling (but without disabling fast scroll)?
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thought i would post here hoping it is not too late.
Note. This does not use AlphabetIndexer, and I don't think using three collections to manipulate the list is a good idea, although it just explains the concept simply.
Below is a basic example of using callbacks:
public LinkedHashMap<Integer,String> sectionList = new LinkedHashMap<Integer,String>();
public HashMap<Integer,Integer> sectionPositions = new HashMap<Integer, Integer>();
public HashMap<Integer,Integer> positionsForSection = new HashMap<Integer, Integer>();
When you have your array of "locations" (pre-ordered), this will create three hash maps to keep track of things, a really simple implementation, very easy to read:
if( locations != null && locations.size() > 0 ) {
//Iterate through the contacts, take the first letter, uppercase it, and use that as a key to reference the alphabetised list constructed above.
for( int i = 0; i < locations.size(); i++ ) {
String startchar =locations.get(i).getStartCharacterForAlphabet();
if( startchar != null ) {
if( sectionList.containsValue(startchar) == false ) {
sectionList.put(Integer.valueOf(i),startchar);
positionsForSection.put(Integer.valueOf(sectionList.size() - 1), Integer.valueOf(i));
}
}
sectionPositions.put(Integer.valueOf(i), sectionList.size() - 1);
}
}
And here are three callbacks:
@Override
public int getPositionForSection(int section) {
return positionsForSection.get(Integer.valueOf(section)).intValue();
}
@Override
public MyLocation getItem(int position) {
if( locations.size() > position ) {
return locations.get(position);
}
return null;
}
@Override
public int getSectionForPosition(int position) {
return sectionPositions.get(Integer.valueOf(position)).intValue();
}
Hope it helps!
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