多列listview错误视图
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【中文标题】多列listview错误视图【英文标题】：Multicolumn listview wrong view 【发布时间】：2016-03-14 07:40:46 【问题描述】：我遇到了多列列表视图的问题。问题是当我向上或向下滚动列表时，主题会更改行。 这是我的活动：
ArrayList<HashMap<String, String>> list = new ArrayList<HashMap<String,String>>();
HashMap<String,String> temp = null; //new HashMap<String, String>();
//TRASFERISCO I DATI DAGLI ARRAY ALLA MAPPA
for(int i = 0 ; i < 24 ; i++)
temp = new HashMap<String, String>();
temp.put(FIRST_COLUMN, i + " " + Array_Nome[i]);
temp.put(SECOND_COLUMN, Array_Cognome[i]);
temp.put(THIRD_COLUMN, Array_Cellulare[i]);
temp.put(FOURTH_COLUMN, Array_UUID[i]);
list.add(temp);
ListView listView=(ListView)findViewById(R.id.listView1);
MultiColoumnAdapter adapter=new MultiColoumnAdapter(this, list);
listView.setAdapter(adapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener()
@Override
public void onItemClick(AdapterView<?> parent, final View view, int position, long id)
int pos=position+1;
Toast.makeText(MainActivity.this, Integer.toString(pos)+" Clicked", Toast.LENGTH_SHORT).show();
);
这是适配器：
public class MultiColoumnAdapter extends BaseAdapter
public ArrayList<HashMap<String, String>> list;
Activity activity;
TextView txtFirst;
TextView txtSecond;
TextView txtThird;
TextView txtFourth;
public MultiColoumnAdapter(Activity activity, ArrayList<HashMap<String, String>> list)
super();
this.activity=activity;
this.list=list;
@Override
public int getCount()
// TODO Auto-generated method stub
return list.size();
@Override
public Object getItem(int position)
// TODO Auto-generated method stub
return list.get(position);
@Override
public long getItemId(int position)
// TODO Auto-generated method stub
return 0;
@Override
public View getView(int position, View convertView, ViewGroup parent)
// TODO Auto-generated method stub
LayoutInflater inflater=activity.getLayoutInflater();
if(convertView == null)
convertView=inflater.inflate(R.layout.colmn_row, null);
txtFirst=(TextView) convertView.findViewById(R.id.name);
txtSecond=(TextView) convertView.findViewById(R.id.gender);
txtThird=(TextView) convertView.findViewById(R.id.age);
txtFourth=(TextView) convertView.findViewById(R.id.status);
else
HashMap<String, String> map=list.get(position);
txtFirst.setText(map.get(FIRST_COLUMN));
txtSecond.setText(map.get(SECOND_COLUMN));
txtThird.setText(map.get(THIRD_COLUMN));
txtFourth.setText(map.get(FOURTH_COLUMN));
return convertView;
最后是列行：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_
android:layout_>
<TextView
android:id="@+id/name"
android:layout_
android:layout_
android:layout_weight="1"
android:textStyle="bold"
android:textSize="22sp"/>
<TextView
android:id="@+id/gender"
android:layout_
android:layout_
android:layout_weight="1"
android:textSize="22sp"/>
<TextView
android:id="@+id/age"
android:layout_
android:layout_
android:layout_weight="0.5"
android:textSize="22sp"/>
<TextView
android:id="@+id/status"
android:layout_
android:layout_
android:layout_weight="1"
android:textSize="22sp"/>
结果是这样的：
1 马克·汤姆森 12345678
2 约翰·史密斯 54654879
3 玛丽亚·特朗普 45869958
向上/向下滚动后：
3 玛丽亚·特朗普 45869958
1 马克汤姆森 12345678
2 约翰·史密斯 54654879
【问题讨论】：
尝试更改getItemId：返回位置而不是0 【参考方案1】：您的 if(convertView == null) 块应更改如下，因为您的 else 案例为空。
if(convertView == null)
ViewHolder viewHolder = new ViewHolder();
convertView=inflater.inflate(R.layout.colmn_row, null);
viewHolder.txtFirst=(TextView) convertView.findViewById(R.id.name);
viewHolder.txtSecond=(TextView) convertView.findViewById(R.id.gender);
viewHolder.txtThird=(TextView) convertView.findViewById(R.id.age);
viewHolder.txtFourth=(TextView) convertView.findViewById(R.id.status);
convertView.setTag(viewHolder)
else
ViewHolder viewHolder = convertView.getTag(viewHolder);
ViewHolder 是适配器中的内部类，代码如下
public class ViewHolder
TextView txtFirst,txtSecond,txtThird,txtFourth;
试试看，如果它有效，请告诉我。
这称为视图模式。在此处阅读。https://developer.android.com/training/improving-layouts/smooth-scrolling.html#ViewHolder
【讨论】：
【参考方案2】：感谢大家的建议。 这对我很有用
private class ViewHolder
TextView txtFirst;
TextView txtThird;
TextView txtSecond;
TextView txtFourth;
@Override
public View getView(int position, View convertView, ViewGroup parent)
// TODO Auto-generated method stub
ViewHolder holder;
LayoutInflater inflater=activity.getLayoutInflater();
if(convertView == null)
holder = new ViewHolder();
convertView=inflater.inflate(R.layout.colmn_row, null);
holder.txtFirst=(TextView) convertView.findViewById(R.id.name);
holder.txtSecond=(TextView) convertView.findViewById(R.id.gender);
holder.txtThird=(TextView) convertView.findViewById(R.id.age);
holder.txtFourth=(TextView) convertView.findViewById(R.id.status);
convertView.setTag(holder);
else
holder = (ViewHolder) convertView.getTag();
HashMap<String, String> map=list.get(position);
holder.txtFirst.setText(map.get(FIRST_COLUMN));
holder.txtSecond.setText(map.get(SECOND_COLUMN));
holder.txtThird.setText(map.get(THIRD_COLUMN));
holder.txtFourth.setText(map.get(FOURTH_COLUMN));
return convertView;
【讨论】：
【参考方案3】：在 else 情况下，您的 getView 函数没有设置您的 textView 变量。如果你不这样做，你就会搞砸回收利用。
【讨论】：
【参考方案4】：在你的getView
@Override
public View getView(int position, View convertView, ViewGroup parent)
// TODO Auto-generated method stub
ViewHolder viewHolder;
LayoutInflater inflater=activity.getLayoutInflater();
if(convertView == null)
convertView=inflater.inflate(R.layout.colmn_row, null);
txtFirst=(TextView) convertView.findViewById(R.id.name);
txtSecond=(TextView) convertView.findViewById(R.id.gender);
txtThird=(TextView) convertView.findViewById(R.id.age);
txtFourth=(TextView) convertView.findViewById(R.id.status);
convertView .setTag(viewHolder);
else
viewHolder = (ViewHolder) convertView .getTag();
//And if you want to manipulate them u must use ViewHolder variable
HashMap<String, String> map=list.get(position);
viewHolder.txtFirst.setText(map.get(FIRST_COLUMN));
viewHolder.txtSecond.setText(map.get(SECOND_COLUMN));
viewHolder.txtThird.setText(map.get(THIRD_COLUMN));
viewHolder.txtFourth.setText(map.get(FOURTH_COLUMN));
return convertView;
当然，如果你还没有 ViewHolder 创建一个这样的
/**
* Creating ViewHolder , witch create adapter item elements
*/
static class ViewHolder
public TextView txtFirst;
public TextView txtThird;
public TextView txtSecond;
public TextView txtFourth;
【讨论】：
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