android - Api 27 空对象引用
问题描述
此代码适用于 api 23,但在 api 27 中不起作用。它向我显示了这条消息:
Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
有人可以帮忙吗?
我无法解决这个问题。我现在被困了1个多星期。
代码是:
public class AdapterMenuList extends BaseAdapter {
private Activity activity;
public AdapterMenuList(Activity act) {
this.activity = act;
}
public int getCount() {
return ActivityMenuList.Menu_ID.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if(convertView == null){
LayoutInflater inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.lsv_item_menu_list, null);
holder = new ViewHolder();
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
holder.nameProduct = convertView.findViewById(R.id.nameProduct);
holder.price50Text = convertView.findViewById(R.id.price50Text);
holder.price100Text = convertView.findViewById(R.id.price100Text);
holder.imgThumb = convertView.findViewById(R.id.imgThumb);
holder.nameProduct.setText(ActivityMenuList.Menu_name.get(position));
if(ActivityMenuList.Category_ID == 1 ){
holder.price50Text.setText("Pret 50 Tb: "+ActivityMenuList.Menu_price50.get(position)+" "+ActivityMenuList.Currency);
holder.price100Text.setText("Pret 100 Tb: "+ActivityMenuList.Menu_price100.get(position)+" "+ActivityMenuList.Currency);
}else{
holder.price50Text.setText("Pret: "+ActivityMenuList.Menu_price50.get(position)+" "+ActivityMenuList.Currency);
holder.price100Text.setVisibility(View.GONE);
}
Picasso.with(activity).load(Config.ADMIN_PANEL_URL+"/"+ActivityMenuList.Menu_image.get(position)).placeholder(R.drawable.loading).into(holder.imgThumb);
return convertView;
}
static class ViewHolder {
TextView nameProduct, price50Text, price100Text;
ImageView imgThumb;
}
}
解决方案
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