Ho un problema molto strano durante l'utilizzo di ListView.ListView non esegue il rendering di tutti gli elementi fino all'interazione con
Solo una parte degli elementi del mio adattatore viene renderizzata in listview sullo schermo ma quando interagisco con il listview (cioè tenta di scorrerlo) tutti gli elementi sono renderizzati correttamente.
Questo fenonemon si verifica solo se ho meno elementi di quanto lo schermo può mostrare. Dai un'occhiata a questi screenshot qui sotto.
Prima di interazione:
Dopo interazione: codice
fonte di attività in cui l'aggiunta di elementi:
String[] jRests = getResources().getStringArray(R.array.j_restaurants);
String[] lRests = getResources().getStringArray(R.array.l_restaurants);
items = new ArrayList<Object>();
items.add(getString(R.string.campus_j));
for(String item : jRests){
String[] val = item.split(",,,");
items.add(new FoodSectionListItem(new Restaurant(val[0], val[1], val[2], "")));
}
items.add(getString(R.string.campus_l));
for(String item : lRests){
String[] val = item.split(",,,");
items.add(new FoodSectionListItem(new Restaurant(val[0], val[1], val[2], "")));
}
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
adapter = new BaseSectionAdapter(this, R.layout.list_item_fragment_header);
if(!isTabletView()){
adapter.setSelectedItem(-1);
}
adapter.setItems(items);
Codice di adattatore:
public class BaseSectionAdapter extends AmazingAdapter {
private LayoutInflater inflater;
private int selectedItem = 0;
private List<Object> items;
private List<SectionItem> sections = new ArrayList<SectionItem>(10);
private List<Class> itemTypes = new ArrayList<Class>();
private List<Integer> sectionPositions = new ArrayList<Integer>();
private int listHeaderLayoutId;
private View headerView;
public static interface ISectionListItem {
public void setProps(View convertView, int position, int selectedItem);
public View getLayout(LayoutInflater inflater);
}
private class SectionItem implements Serializable {
private static final long serialVersionUID = -8930010937740160935L;
String text;
int position;
public SectionItem(String text, int position) {
this.text = text;
this.position = position;
}
}
public BaseSectionAdapter(Context context, int listHeaderLayoutId) {
this.listHeaderLayoutId = listHeaderLayoutId;
init(context);
}
public BaseSectionAdapter(Context context, int listHeaderLayoutId, List<Object> listItems) {
this.listHeaderLayoutId = listHeaderLayoutId;
init(context);
initListItems(listItems);
}
private void init(Context context) {
inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
public void setSelectedItem(int position) {
selectedItem = position;
}
// public List<ListItem> getItems() {
// return items;
// }
private void initListItems(List<Object> itemList) {
int curSection = -1;
//int curPosition = 0;
//curSection = 0;
this.items = itemList;
itemTypes.clear();
sections.clear();
sectionPositions.clear();
int listSize = itemList.size();
for(int i = 0; i < listSize; i++){
Object currentItem = items.get(i);
if(currentItem instanceof String){
sections.add(new SectionItem((String) currentItem,i));
curSection++;
}
if(!itemTypes.contains(currentItem.getClass())){
itemTypes.add(currentItem.getClass());
}
sectionPositions.add(curSection);
}
Log.d("test", "No of items = "+items.size());
Log.d("test", "No of itemtypes = "+itemTypes.size());
Log.d("test", "View type count = "+getViewTypeCount());
}
public void setItems(List<Object> itemList) {
initListItems(itemList);
}
public int getCount() {
return items==null?0:items.size();
}
@Override
public int getViewTypeCount(){
return (itemTypes.size() == 0)?1:itemTypes.size();
}
@Override
public int getItemViewType(int position){
return itemTypes.indexOf(items.get(position).getClass());
}
@Override
public boolean isEnabled(int position){
return !(items.get(position) instanceof String || items.get(position) instanceof EmptySectionListItem);
}
@Override
public Object getItem(int position) {
return items.get(position);
}
public long getItemId(int position) {
return position;
}
@Override
protected void onNextPageRequested(int page) {
// TODO Auto-generated method stub
}
@Override
protected void bindSectionHeader(View view, int position,
boolean displaySectionHeader) {
// TextView lSectionTitle = (TextView) view
// .findViewById(R.id.txt_list_header);
// if (displaySectionHeader) {
// lSectionTitle.setVisibility(View.VISIBLE);
// lSectionTitle
// .setText(getSections()[getSectionForPosition(position)]);
// } else {
// lSectionTitle.setVisibility(View.GONE);
// }
}
@Override
public View getAmazingView(int position, View convertView, ViewGroup parent) {
Object curItemObject = items.get(position);
boolean isHeader = (curItemObject instanceof String);
if(convertView == null){
if(isHeader && headerView != null){
convertView = headerView;
}else if(isHeader){
convertView = inflater.inflate(listHeaderLayoutId, null);
headerView = convertView;
}else{
convertView = ((ISectionListItem) curItemObject).getLayout(inflater);
}
}
if(isHeader){
TextView header = ((TextView)convertView.findViewById(R.id.txt_list_header));
header.setText((String)curItemObject);
}else{
((ISectionListItem)curItemObject).setProps(convertView, position, selectedItem);
}
return convertView;
}
@Override
public void configurePinnedHeader(View header, int position, int alpha) {
TextView textView = ((TextView)header.findViewById(R.id.txt_list_header));
textView.setText(getSections()[getSectionForPosition(position)]);
}
@Override
public int getPositionForSection(int section) {
if(section >= sections.size()){
return 0;
}
return sections.get(section).position;
}
@Override
public int getSectionForPosition(int position) {
return sectionPositions.get(position);
}
@Override
public String[] getSections() {
String[] res = new String[sections.size()];
for (int i = 0; i < res.length; i++) {
res[i] = sections.get(i).text;
}
return res;
}
}
Codice di aspetto:
LinearLayout layout = new LinearLayout(this);
layout.setOrientation(LinearLayout.HORIZONTAL);
FrameLayout listLayout = new FrameLayout(this);
LinearLayout.LayoutParams listParams = new LinearLayout.LayoutParams(0, FrameLayout.LayoutParams.MATCH_PARENT);
listParams.weight = 1;
listLayout.setId(LIST_FRAGMENT_VIEW_ID);
FrameLayout detailLayout = new FrameLayout(this);
LinearLayout.LayoutParams detailParams = new LinearLayout.LayoutParams(0, FrameLayout.LayoutParams.MATCH_PARENT);
detailParams.weight = 2;
detailLayout.setId(DETAIL_FRAGMENT_VIEW_ID);
layout.addView(listLayout, listParams);
layout.addView(detailLayout, detailParams);
if(savedInstanceState == null){
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.add(listLayout.getId(), (Fragment) listFragment, TWO_PANEL_LIST_FRAGMENT_TAG);
ft.add(detailLayout.getId(), detailFragment);
ft.commit();
}
setContentView(layout);
puoi aggiungere qualche codice di adattatore ..? – Kamal
aggiungi il codice sorgente nel punto in cui aggiungi elementi alla fonte di dati di backup della listview e crea la scheda –
anche la sorgente di layout di ListView.:) –