从上到下滚动时如何自动停止对项目的列表视图取消选择？
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【中文标题】从上到下滚动时如何自动停止对项目的列表视图取消选择？【英文标题】：how to stop listview deselection on items automatically when scrolling top to bottom? 【发布时间】：2016-04-09 07:48:47 【问题描述】：我有一个列表视图并使用 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列表视图中的默认状态。如何解决这个问题呢。请帮忙。我是安卓新手。
@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("addtocardmap final", "********" + 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;
【问题讨论】：
使用视图持有者，请分享代码以供审核 这是我的代码，我也使用了视图支架。它不工作。 【参考方案1】：查看我的适配器并像这样更改您的适配器
@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;
【讨论】：
【参考方案2】：这个例子是使用数组列表来完成的这个逻辑
在你的 pojo 类中添加布尔标志说
Boolean isSelected;
在其中应用 getter 和 setter。 最初设置 isSelected = false 的所有值，以便不选择列表项
现在在 onItem 单击期间将当前对象的 isSelected 设置为 true 像这样
在 onItemClick 内应用这个
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();
;
现在在您的适配器类的 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;
【讨论】：
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