我有一个listview并使用BaseAdapter添加了内容。它工作正常，但是当我要从上到下向下滚动项目时，它会自动将所选项目的阶段更改为listview中的默认状态。如何解决这个问题呢。请帮忙。我是新手。
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sub_menu_list);
ActionBar actionBar = getSupportActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
customDialog = new CustomDialog(TakeoutListActivity.this);
Intent intent = getIntent();
Obj = intent.getStringExtra("CateValue");
Log.e("Obj", "" + Obj);
addtocardArr = new ArrayList<HashMap<String, String>>();
listView = (ListView) findViewById(R.id.subcategory_list);
notificationCount = 0;
new AsyncTask<Void, Void, Void>() {
@Override
protected void onPreExecute() {
super.onPreExecute();
customDialog.setContentView(R.layout.cus_dialog);
customDialog.show();
}
@Override
protected Void doInBackground(Void... params) {
if (Obj != null) {
try {
JSONObject jsonObject = new JSONObject(Obj);
JSONArray jsonArray = jsonObject.getJSONArray("Details");
SubCateArrayList = new ArrayList<HashMap<String, String>>();
/*for (int i = 0; i < jsonArray.length(); i++) {
SubCateHashMapList = new HashMap<String, String>();
JSONObject DetailsObj = jsonArray.getJSONObject(i);
SubCateHashMapList.put("ItemName", DetailsObj.optString("ItemName"));
JSONArray AllItemArray = DetailsObj.getJSONArray("Allitems");
//Log.e("AllItemArray", "" + AllItemArray);
SubCateArrayList.add(SubCateHashMapList);
for (int j = 0; j < AllItemArray.length(); j++) {
SubInner = new HashMap<String, String>();
JSONObject AllItemObj = AllItemArray.getJSONObject(j);
SubInner.put("foodid", AllItemObj.getString("foodid"));
SubInner.put("name", AllItemObj.getString("name"));
SubInner.put("Description", AllItemObj.getString("Description"));
SubInner.put("image", AllItemObj.getString("image"));
SubInner.put("price", AllItemObj.getString("price"));
SubInner.put("favorite", AllItemObj.getString("favorite"));
SubCateArrayList.add(SubInner);
Log.e("SubCateArrayList", "" + SubCateArrayList);
}
}
Log.e("SubCateArrayList", "" + SubCateArrayList);*/
SubCateArrayList = new ArrayList<HashMap<String, String>>();
// SubCateArrayList.clear();
// SubCateInnerArrayList = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < jsonArray.length(); i++) {
SubCateHashMapList = new HashMap<String, String>();
JSONObject DetailsObj = jsonArray.getJSONObject(i);
SubCateHashMapList.put("ItemName", DetailsObj.optString("ItemName"));
Log.e("SubCateHashMapList>>>>>>>>>", "" + SubCateHashMapList);
JSONArray AllItemArray = DetailsObj.getJSONArray("Allitems");
//Log.e("AllItemArray", "" + AllItemArray);
//SubCateArrayList.add(SubCateHashMapList);
for (int j=0; j<AllItemArray.length();j++)
{
SubInner = new HashMap<String, String>();
JSONObject AllItemObj = AllItemArray.getJSONObject(j);
SubInner.put("foodid", AllItemObj.getString("foodid"));
SubInner.put("name", AllItemObj.getString("name"));
SubInner.put("Description", AllItemObj.getString("Description"));
SubInner.put("image", AllItemObj.getString("image"));
SubInner.put("price", AllItemObj.getString("price"));
SubInner.put("favorite", AllItemObj.getString("favorite"));
SubCateArrayList.add(SubInner);
Log.d("SubCateInnerArrayList2349587", "" + SubCateArrayList);
}
//SubInner.putAll(SubCateHashMapList);
}
Log.e("SubCateArrayList", "" + SubCateArrayList);
} catch (JSONException e) {
e.printStackTrace();
}
} else {
ErrorMsg = "JSONError";
}
return null;
}
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
customDialog.dismiss();
subCateListAdapter = new SubCateListAdapter(TakeoutListActivity.this, SubCateArrayList);
subCateListAdapter.notifyDataSetInvalidated();
listView.setFadingEdgeLength(0);
listView.setAdapter(subCateListAdapter);
}
}.execute();
}
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.cart_menu,menu);
MenuItem item = menu.findItem(R.id.cart_add);
drawable = (LayerDrawable)item.getIcon();
Log.d("notificationCount", "" + notificationCount);
BadgeHelper.setBadgeCount(this, drawable, notificationCount);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.cart_homeID)
{
Intent homeIntent = new Intent(TakeoutListActivity.this,HomeRestaurant.class);
startActivity(homeIntent);
TakeoutListActivity.this.finish();
}
if (id==R.id.cart_add)
{
if (notificationCount==0)
{
AlertDialog.Builder builder = new AlertDialog.Builder(TakeoutListActivity.this);
builder.setMessage("Please add to cart");
builder.setNegativeButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
builder.show();
}
else
{
Intent nextact = new Intent(TakeoutListActivity.this, AddCartActivity.class);
Bundle bundle = new Bundle();
bundle.putSerializable("Selected", addtocardArr);
nextact.putExtras(bundle);
// nextact.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(nextact);
// Log.d（＆＃34; addtocardmap final＆＃34;，＆＃34; ********＆＃34; + addtocardmap.toString（））;
}
return true;
}
return super.onOptionsItemSelected(item);
}
private class SubCateListAdapter extends BaseAdapter {
LayoutInflater layoutInflater;
Context context;
HashMap<String, String> display = new HashMap<String, String>();
ArrayList<HashMap<String, String>> data;
int count = 0;
String strcount="";
String[] clickedpositions;
int locid;
HashMap<String,String> toaddData;
public SubCateListAdapter(Context subMenuListActivity, ArrayList<HashMap<String, String>> subCateArrayList) {
this.context = subMenuListActivity;
this.data = subCateArrayList;
}
@Override
public int getCount() {
return data.size();
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final TextView menuTitle, subMenuTitle, Price, des, countText, addCart, remove;
ImageView itemImage, FavImage;
ImageButton add, minus;
toaddData = new HashMap<String,String>();
display = data.get(position);
layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view =layoutInflater.inflate(R.layout.takeout_listitem, parent, false);
//menuTitle = (TextView)view.findViewById(R.id.menu_title);
subMenuTitle = (TextView) view.findViewById(R.id.sub_title);
Price = (TextView) view.findViewById(R.id.price);
countText = (TextView) view.findViewById(R.id.count_text);
des = (TextView) view.findViewById(R.id.menu_des);
itemImage = (ImageView) view.findViewById(R.id.menu_Image);
FavImage = (ImageView) view.findViewById(R.id.fav);
addCart = (TextView)view.findViewById(R.id.addToCart);
add = (ImageButton)view.findViewById(R.id.add);
minus = (ImageButton)view.findViewById(R.id.minus);
//menuTitle.setText(display.get("ItemName"));
subMenuTitle.setText(display.get("name"));
des.setText(display.get("Description"));
Price.setText(display.get("price"));
Glide.with(getApplicationContext()).load(display.get("image")).error(R.drawable.list_bg).crossFade(500).into(itemImage);
add.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
textCount = Integer.parseInt(countText.getText().toString());
textCount++;
strcount = String.valueOf(textCount);
countText.setText(strcount);
}
});
minus.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int textCount = Integer.parseInt(countText.getText().toString());
textCount--;
if(textCount<=0) {
strcount = String.valueOf(textCount);
countText.setText("0");
}
else
{
strcount = String.valueOf(textCount);
countText.setText(strcount);
}
}
});
addCart.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
addtocardmap = new HashMap<String, String>();
recid = data.get(position).get("foodid");
pdttitle = data.get(position).get("name");
foodprice = data.get(position).get("price");
notifycount = countText.getText().toString();
poscount +=position;
strposcount += String.valueOf(position) + ",";
Log.e("strposcount", "" + strposcount);
toaddData.put("foodid", recid);
toaddData.put("name", pdttitle);
toaddData.put("notifycount", notifycount);
if(addtocardArr.contains(addtocardmap))
{
String quan = addtocardArr.get(position).get("qunatity");
int intquan = Integer.parseInt(quan)+Integer.parseInt(strcount);
strcount = String.valueOf(intquan);
// addtocardArr.remove(position - 1);
addtocardmap.put("foodid", recid);
addtocardmap.put("name", pdttitle);
addtocardmap.put("price", foodprice);
addtocardmap.put("qunatity", notifycount);
addtocardArr.set(position,addtocardmap);
Log.d("recid", "******" + recid);
Log.d("pdttitle", "******" + pdttitle);
Log.d("Quantity", "******" + notifycount);
Log.d("foodprice", "******" + foodprice);
Log.d("item position", "******" + position);
Log.d("addtocardmap", "********" + addtocardmap);
//addtocardArr.remove(position);
Log.d("After remove duplicates", "********" + addtocardArr);
}
else
{
//in object
addtocardmap.put("foodid", recid);
addtocardmap.put("name", pdttitle);
addtocardmap.put("price", foodprice);
addtocardmap.put("qunatity", notifycount);
//in array
Log.d("recid", "******" + recid);
Log.d("pdttitle", "******" + pdttitle);
Log.d("Quantity", "******" + notifycount);
Log.d("foodprice", "******" + foodprice);
Log.d("item position", "******" + position);
Log.d("addtocardmap", "********" + addtocardmap);
}
//tosendData.add(toaddData);
addtocardArr.add(addtocardmap);
Log.d("to add non-duplicate element", "" + addtocardArr);
// addtocardArr.add(new SelectedItems());
notificationCount++;
updateNotificationCount(String.valueOf(notificationCount));
}
});
return view;
}
}
答案 0 :(得分：1)
查看我的适配器并按照
更改适配器 @Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView;
ViewHolder holder = null;
if (view == null) {
view = LayoutInflater.from(parent.getContext()).inflate(R.layout.food_list_item, null);
holder = new ViewHolder();
holder.title = (TextView) view.findViewById(R.id.tvFoodItemTitle);
holder.desc = (TextView) view.findViewById(R.id.tvFoodItemDesc);
holder.image = (ImageView) view.findViewById(R.id.ivFoodItem);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
holder.title.setText(getItem(position).getName());
holder.desc.setText(getItem(position).getDescription());
String imagePath = "assets://" + getItem(position).getImagePath();
ImageLoader.getInstance().displayImage(imagePath, holder.image);
return view;
}
class ViewHolder {
TextView title;
TextView desc;
ImageView image;
}
答案 1 :(得分：0)
这个例子是使用arraylist来完成的，假设 lstcategory 作为你的列表，你也可以在这里为你的hashmap做类似的事我只是展示一个简单的逻辑来解决这个问题你可以做到这一点如果你得到它这个逻辑
在你的pojo类中添加boolean标志说
Boolean isSelected;
在其中应用getter和setter。 最初设置isSelected = false的所有值，以便不选择任何列表项
现在在onItem点击期间设置当前对象的isSelected为true 像这样
onItemClick中的应用此
OnItemClickListener listViewOnItemClick = new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapter, View arg1, int position, long id) {
for(int i =0;i < lstcategory.size();i++}{
lstcategory.get(i).setIsSelected(false);
}
lstcategory.get(position).setIsSelected(true);
mAdapter.notifyDataSetChanged();
}
};
现在在适配器类的getview中检查列表项是否已检查。
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final View view = View.inflate(context, R.layout.item_list, null);
if (lstcategory.get(position).getIsSelected()) {
// set selected your color
}else{
//set default color
}
return view;
}