本文介绍了滚动ExpendableListView后计数器的值更改的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我有一个Items的ExpandableListView，在清单项目上我有一个TextView，它带有两个按钮，可在单击时增加或减少TextView中的值.每当我尝试滚动列表时，都会出现此问题.如果我增加一项，然后滚动列表，则值会混合(因为ListView不断回收其视图)，而且我不知道如何解决它.
I have an ExpandableListView of items and on list item I have TextView with two buttons to increment or decrements the value in TextView on clicks. The problem occurs every time I try to scroll the list. If I increment one item and then scroll the list the values get mixed (becouse the ListView keeps recycling its views) and I don't know how to fix it.
我已经尝试了很多在这里找到的失误，是的，这可能是重复的，但是我无法用发现的任何方法来解决我的问题.
I have tried many soulutions I have found here, so yes this may be a duplicate, but I wasn't able to solve my problem with any method I have found.
我的ExpandableListAdapter.java
My ExpandableListAdapter.java
import android.content.Context;
import android.graphics.Typeface;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.Button;
import android.widget.TextView;
import java.util.HashMap;
import java.util.List;
public class ExpandableListAdapter extends BaseExpandableListAdapter {
public static class ViewHolder {
TextView childText;
TextView counterText;
Button addItemButton;
Button deleteItemButton;
int quantity = 0;
}
private Context context;
private List<String> listDataHeader;
private HashMap<String, List<String>> listHashMap;
public ExpandableListAdapter(Context context, List<String> listDataHeader, HashMap<String, List<String>> listHashMap) {
this.context = context;
this.listDataHeader = listDataHeader;
this.listHashMap = listHashMap;
}
@Override
public int getGroupCount() {
return listDataHeader.size();
}
@Override
public int getChildrenCount(int groupPosition) {
return listHashMap.get(listDataHeader.get(groupPosition)).size();
}
@Override
public Object getGroup(int groupPosition) {
return listDataHeader.get(groupPosition);
}
@Override
public Object getChild(int groupPosition, int childPosition) {
return listHashMap.get(listDataHeader.get(groupPosition)).get(childPosition);
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
String headerTitle = (String) getGroup(groupPosition);
if(convertView == null) {
LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_group, null);
}
TextView listHeader = (TextView) convertView.findViewById(R.id.list_header);
listHeader.setTypeface(null, Typeface.BOLD);
listHeader.setText(headerTitle);
return convertView;
}
@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
final ViewHolder viewHolder;
if(convertView == null) {
LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_item, null);
TextView textListChild = (TextView) convertView.findViewById(R.id.list_item_header);
TextView itemsCounter = (TextView) convertView.findViewById(R.id.items_counter);
Button addItemButton = (Button) convertView.findViewById(R.id.plus_btn);
viewHolder = new ViewHolder();
viewHolder.childText = textListChild;
viewHolder.counterText = itemsCounter;
viewHolder.addItemButton = addItemButton;
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
final String childText = (String) getChild(groupPosition, childPosition);
viewHolder.childText.setText(childText);
viewHolder.addItemButton.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
//int itemCount = Integer.parseInt((String)viewHolder.counterText.getText());
//itemCount++;
viewHolder.quantity++;
viewHolder.counterText.setText( Integer.toString(viewHolder.quantity));
PutOrderDrinks.addOrder(childText);
}
});
return convertView;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
推荐答案
尝试使用此适配器:
public class ExpandableListAdapter extends BaseExpandableListAdapter {
class ViewHolder {
TextView childText;
TextView counterText;
Button addItemButton;
Button deleteItemButton;
}
class ChildItem{
String name;
int quantity;
ChildItem(String name, int quantity){
this.name = name;
this.quantity = quantity;
}
}
class Pos{
int group;
int child;
Pos(int group, int child){
this.group = group;
this.child = child;
}
}
private Context context;
private List<String> listDataHeader;
//private HashMap<String, List<String>> listHashMap;
private HashMap<String, List<ChildItem>> listChildMap;
public ExpandableListAdapter(Context context, List<String> listDataHeader, HashMap<String, List<String>> listHashMap) {
this.context = context;
this.listDataHeader = listDataHeader;
listChildMap = new HashMap<>();
for(int i=0; i<getGroupCount(); i++){
List<ChildItem> listTemp = new ArrayList<>();
for(int j=0; j<listHashMap.get(listDataHeader.get(i)).size(); j++){
listTemp.add(new ChildItem(listHashMap.get(listDataHeader.get(i)).get(j), 0));
}
listChildMap.put(listDataHeader.get(i), listTemp);
}
}
@Override
public int getGroupCount() {
return listDataHeader.size();
}
@Override
public int getChildrenCount(int groupPosition) {
return listChildMap.get(listDataHeader.get(groupPosition)).size();
}
@Override
public String getGroup(int groupPosition) {
return listDataHeader.get(groupPosition);
}
@Override
public ChildItem getChild(int groupPosition, int childPosition) {
return listChildMap.get(listDataHeader.get(groupPosition)).get(childPosition);
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
String headerTitle = getGroup(groupPosition);
if(convertView == null) {
LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_group, null);
}
TextView listHeader = (TextView) convertView.findViewById(R.id.list_header);
listHeader.setTypeface(null, Typeface.BOLD);
listHeader.setText(headerTitle);
return convertView;
}
@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
ViewHolder viewHolder;
if(convertView == null) {
LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_item, null);
TextView textListChild = (TextView) convertView.findViewById(R.id.list_item_header);
TextView itemsCounter = (TextView) convertView.findViewById(R.id.items_counter);
Button addItemButton = (Button) convertView.findViewById(R.id.plus_btn);
viewHolder = new ViewHolder();
viewHolder.childText = textListChild;
viewHolder.counterText = itemsCounter;
viewHolder.addItemButton = addItemButton;
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
ChildItem child = getChild(groupPosition, childPosition);
viewHolder.childText.setText(child.name);
viewHolder.counterText.setText("" + child.quantity);
viewHolder.addItemButton.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
Pos pos = (Pos)v.getTag();
ChildItem selectedItem = getChild(pos.group, pos.child);
selectedItem.quantity = selectedItem.quantity + 1;
notifyDataSetChanged();
PutOrderDrinks.addOrder(selectedItem.name);
}
});
viewHolder.addItemButton.setTag(new Pos(groupPosition, childPosition));
convertView.setTag(viewHolder);
return convertView;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
这篇关于滚动ExpendableListView后计数器的值更改的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！