Android GridView未使用notifyDataSetChanged()刷新
我使用GridView在两列中显示数据列表。现在,当我对列表的数据进行一些更改并调用NotifyDataSetChange时,它并没有直接刷新。当我滚动视图时,它反映了更改。如何找到解决方法?请帮忙Android GridView未使用notifyDataSetChanged()刷新,android,Android,我使用GridView在两列中显示数据列表。现在,当我对列表的数据进行一些更改并调用NotifyDataSetChange时,它并没有直接刷新。当我滚动视图时,它反映了更改。如何找到解决方法?请帮忙 public class MenuGridViewAdapter extends BaseAdapter implements View.OnClickListener { Activity activity; ArrayList mArraylist = new ArrayList()
public class MenuGridViewAdapter extends BaseAdapter implements
View.OnClickListener {
Activity activity;
ArrayList mArraylist = new ArrayList();
private TextView mItemName, mDescription;
private TextView mItemRate;
private TextView mQuantity;
private ImageView mAddItem;
private LinearLayout mInYourCart;
private CardView mContainer;
public MenuGridViewAdapter(Activity activity, ArrayList mArraylist) {
this.activity = activity;
this.mArraylist = new ArrayList();
this.mArraylist.clear();
this.mArraylist.addAll(mArraylist);
notifyDataSetChanged();
}
@Override
public int getCount() {
return mArraylist.size();
}
@Override
public Object getItem(int position) {
return mArraylist.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
convertView = LayoutInflater.from(activity).inflate(R.layout.layout_menu_item, null); // inflate the layout
mContainer = convertView.findViewById(R.id.container);
mQuantity = convertView.findViewById(R.id.quantity);
mDescription = convertView.findViewById(R.id.description);
mInYourCart = convertView.findViewById(R.id.added_to_cart);
mItemName = convertView.findViewById(R.id.item_name);
mAddItem = convertView.findViewById(R.id.add_item);
mItemRate = convertView.findViewById(R.id.price);
MenuItemBean bean = (MenuItemBean) mArraylist.get(position);
// Log.e("getProductName ", bean.getProductName());
mItemName.setText("" + bean.getProductName());
mItemRate.setText("CHF " + bean.getRate());
if (bean.getDescription() != null) {
mDescription.setText(bean.getDescription());
} else {
mDescription.setText("");
}
if (Constants.menuFilter.size() == 0) {
mContainer.setVisibility(View.VISIBLE);
} else {
String filter = "";
if (bean.getIs_spicy() == 1) {
filter = "spicy";
}
if (bean.getIs_veg() == 1) {
filter = "Vegetarian";
}
int flag = 0;
for (int i = 0; i < Constants.menuFilter.size(); i++) {
if (Constants.menuFilter.get(i).equalsIgnoreCase(filter)) {
flag = 1;
break;
}
}
if (flag == 1) {
mContainer.setVisibility(View.VISIBLE);
} else {
mContainer.setVisibility(View.GONE);
}
}
if (!bean.getQuantity().equalsIgnoreCase("0")) {
Log.d("ITEMADAPTER:", "UPDATED ITEMS" + "--" + position + "--VISIBLE");
mInYourCart.setVisibility(View.VISIBLE);
mQuantity.setText("" + bean.getQuantity());
} else {
Log.d("ITEMADAPTER:", "UPDATED ITEMS" + "--" + position + "--GONE");
mInYourCart.setVisibility(View.GONE);
mQuantity.setText("" + bean.getQuantity());
}
mAddItem.setTag(Integer.valueOf(position));
mAddItem.setOnClickListener(this);
return convertView;
}
@Override
public void onClick(View v) {
int pos = (int) v.getTag();
int id = v.getId();
MenuItemBean bean = (MenuItemBean) mArraylist.get(pos);
switch (id) {
case R.id.add_item:
FragmentMenuCard fragmentMenuCard = new FragmentMenuCard();
fragmentMenuCard.showAddItemDialog(activity, bean, mQuantity, mInYourCart);
break;
}
}
我从一个函数调用notifyDataSetChanged,该函数在单击事件后调用,该事件将bean.getQuantity值设置为1,例如:
menuiteAdapter.notifyDataSetChanged 第一件事First notifyDataSetChanged only将与数据集的相同引用一起使用。您已经在适配器的构造函数中创建了一个新列表。所以你从这里什么也不能去。它应该尽可能简单
private ArrayList mArraylist = new ArrayList();
public MenuGridViewAdapter(Activity activity, ArrayList mArraylist) {
this.activity = activity;
this.mArraylist = mArraylist;
}
下面是你犯的一些错误。
1.您已创建dataset的新实例,因此notifyDataSetChanged将无法工作。
2.您已在构造函数中调用notifyDataSetChanged为什么?没用
因此,整个要点是数据集引用应该是相同的。然后,只有在同一列表中进行更改时,notifyDataSetChanged才会起作用
建议:-使用GridLayouManager转到RecyclerView。它为ViewHolder模式提供了更好的方法 在适配器中添加更新方法,该方法将更改ArrayList数据。这里有一个例子
public class MenuGridViewAdapter extends BaseAdapter {
public void update(ArrayList<String> data){
mArraylist = data;
notifyDatasetChanged();
}
}
这样,您就不必每次更新列表时都创建适配器。请先阅读。然后带着一个适当的问题回来。很抱歉这样问@ADM。你能帮帮忙吗?你没听懂!你必须添加你的代码。没有代码,谁也帮不上忙。添加适配器的代码和设置适配器的位置。好的。现在好了吗?你能帮忙吗。如果需要更多的细节,请告诉我。谢谢。我来检查一下。根据此链接进行了第1点和第2点中提到的更改:-[。无论如何,感谢您将应用这些更改并进行检查。感谢@ADM。它与RecyclerView和GridLayoutManager一起工作,但与GridView不一起。不知道为什么。它将与GridView一起工作。尝试一下。不过,您已经使用RecyclerView,这非常好。祝您好运
public class MenuGridViewAdapter extends BaseAdapter {
public void update(ArrayList<String> data){
mArraylist = data;
notifyDatasetChanged();
}
}
adapter.update(updatedList);