Android notifyDataSetChange无法从自定义适配器工作

当我重新填充我的

列表视图

时，我从我的

适配器

调用一个特定的方法

问题：

public class ReceiptListAdapter extends BaseAdapter {

    public List<Receipt> receiptlist;
    private Context context;
    private LayoutInflater inflater;
    private DateHelpers dateH;

    public ReceiptListAdapter(Activity activity, Context mcontext, List<Receipt> rl) {
        context = mcontext;
        receiptlist = rl;
        Collections.reverse(receiptlist);
        inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        dateH = new DateHelpers();
    }

    @Override
    public int getCount() {
        try {
            int size = receiptlist.size();
            return size;
        } catch(NullPointerException ex) {
            return 0;
        }
    }

    public void updateReceiptsList(List<Receipt> newlist) {
        receiptlist = newlist;
        this.notifyDataSetChanged();
    }

    @Override
    public Receipt getItem(int i) {
        return receiptlist.get(i);
    }

    @Override
    public long getItemId(int i) {
        return receiptlist.get(i).getReceiptId() ;
    }

    private String getPuntenString(Receipt r) {
        if(r.getPoints().equals("1")) {
            return "1 punt";
        }
        return r.getPoints()+" punten";
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View vi=convertView;

        final Receipt receipt = receiptlist.get(position);
        ReceiptViewHolder receiptviewholder;
        Typeface tf_hn = Typeface.createFromAsset(context.getAssets(), "helveticaneue.ttf");        
        Typeface tf_hn_bold = Typeface.createFromAsset(context.getAssets(), "helveticaneuebd.ttf");

        if (vi == null) { //convertview==null
            receiptviewholder = new ReceiptViewHolder();
            vi = inflater.inflate(R.layout.view_listitem_receipt, null);
            vi.setOnClickListener(null);
            vi.setOnLongClickListener(null);
            vi.setLongClickable(false);
            receiptviewholder.shop = (TextView) vi.findViewById(R.id.tv_listitemreceipt_shop);
            receiptviewholder.date = (TextView) vi.findViewById(R.id.tv_listitemreceipt_date);
            receiptviewholder.price = (TextView) vi.findViewById(R.id.tv_listitemreceipt_price);
            receiptviewholder.points = (TextView) vi.findViewById(R.id.tv_listitemreceipt_points);
            receiptviewholder.shop.setTypeface(tf_hn_bold);
            receiptviewholder.price.setTypeface(tf_hn_bold);
            vi.setTag(receiptviewholder);
        }else{//convertview is not null
            receiptviewholder = (ReceiptViewHolder)vi.getTag();
        }

        receiptviewholder.shop.setText(receipt.getShop());
        receiptviewholder.date.setText(dateH.timestampToDateString(Long.parseLong(receipt.getPurchaseDate())));
        receiptviewholder.price.setText("€ "+receipt.getPrice());
        receiptviewholder.points.setText(getPuntenString(receipt));

        vi.setClickable(false);
        return vi;
    }

    public static class ReceiptViewHolder {
        public TextView shop;
        public TextView date;
        public TextView price;
        public TextView points;
    }

    public Object getFilter() {
        // XXX Auto-generated method stub
        return null;
    }

}

当我从我的

适配器

调用

更新接收列表

时，数据会被刷新，但我的

列表视图

不会反映更改

问题：

public class ReceiptListAdapter extends BaseAdapter {

    public List<Receipt> receiptlist;
    private Context context;
    private LayoutInflater inflater;
    private DateHelpers dateH;

    public ReceiptListAdapter(Activity activity, Context mcontext, List<Receipt> rl) {
        context = mcontext;
        receiptlist = rl;
        Collections.reverse(receiptlist);
        inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        dateH = new DateHelpers();
    }

    @Override
    public int getCount() {
        try {
            int size = receiptlist.size();
            return size;
        } catch(NullPointerException ex) {
            return 0;
        }
    }

    public void updateReceiptsList(List<Receipt> newlist) {
        receiptlist = newlist;
        this.notifyDataSetChanged();
    }

    @Override
    public Receipt getItem(int i) {
        return receiptlist.get(i);
    }

    @Override
    public long getItemId(int i) {
        return receiptlist.get(i).getReceiptId() ;
    }

    private String getPuntenString(Receipt r) {
        if(r.getPoints().equals("1")) {
            return "1 punt";
        }
        return r.getPoints()+" punten";
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View vi=convertView;

        final Receipt receipt = receiptlist.get(position);
        ReceiptViewHolder receiptviewholder;
        Typeface tf_hn = Typeface.createFromAsset(context.getAssets(), "helveticaneue.ttf");        
        Typeface tf_hn_bold = Typeface.createFromAsset(context.getAssets(), "helveticaneuebd.ttf");

        if (vi == null) { //convertview==null
            receiptviewholder = new ReceiptViewHolder();
            vi = inflater.inflate(R.layout.view_listitem_receipt, null);
            vi.setOnClickListener(null);
            vi.setOnLongClickListener(null);
            vi.setLongClickable(false);
            receiptviewholder.shop = (TextView) vi.findViewById(R.id.tv_listitemreceipt_shop);
            receiptviewholder.date = (TextView) vi.findViewById(R.id.tv_listitemreceipt_date);
            receiptviewholder.price = (TextView) vi.findViewById(R.id.tv_listitemreceipt_price);
            receiptviewholder.points = (TextView) vi.findViewById(R.id.tv_listitemreceipt_points);
            receiptviewholder.shop.setTypeface(tf_hn_bold);
            receiptviewholder.price.setTypeface(tf_hn_bold);
            vi.setTag(receiptviewholder);
        }else{//convertview is not null
            receiptviewholder = (ReceiptViewHolder)vi.getTag();
        }

        receiptviewholder.shop.setText(receipt.getShop());
        receiptviewholder.date.setText(dateH.timestampToDateString(Long.parseLong(receipt.getPurchaseDate())));
        receiptviewholder.price.setText("€ "+receipt.getPrice());
        receiptviewholder.points.setText(getPuntenString(receipt));

        vi.setClickable(false);
        return vi;
    }

    public static class ReceiptViewHolder {
        public TextView shop;
        public TextView date;
        public TextView price;
        public TextView points;
    }

    public Object getFilter() {
        // XXX Auto-generated method stub
        return null;
    }

}

为什么我的

列表视图

在调用

notifyDataSetChanged

时不显示新数据

适配器：

public class ReceiptListAdapter extends BaseAdapter {

    public List<Receipt> receiptlist;
    private Context context;
    private LayoutInflater inflater;
    private DateHelpers dateH;

    public ReceiptListAdapter(Activity activity, Context mcontext, List<Receipt> rl) {
        context = mcontext;
        receiptlist = rl;
        Collections.reverse(receiptlist);
        inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        dateH = new DateHelpers();
    }

    @Override
    public int getCount() {
        try {
            int size = receiptlist.size();
            return size;
        } catch(NullPointerException ex) {
            return 0;
        }
    }

    public void updateReceiptsList(List<Receipt> newlist) {
        receiptlist = newlist;
        this.notifyDataSetChanged();
    }

    @Override
    public Receipt getItem(int i) {
        return receiptlist.get(i);
    }

    @Override
    public long getItemId(int i) {
        return receiptlist.get(i).getReceiptId() ;
    }

    private String getPuntenString(Receipt r) {
        if(r.getPoints().equals("1")) {
            return "1 punt";
        }
        return r.getPoints()+" punten";
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View vi=convertView;

        final Receipt receipt = receiptlist.get(position);
        ReceiptViewHolder receiptviewholder;
        Typeface tf_hn = Typeface.createFromAsset(context.getAssets(), "helveticaneue.ttf");        
        Typeface tf_hn_bold = Typeface.createFromAsset(context.getAssets(), "helveticaneuebd.ttf");

        if (vi == null) { //convertview==null
            receiptviewholder = new ReceiptViewHolder();
            vi = inflater.inflate(R.layout.view_listitem_receipt, null);
            vi.setOnClickListener(null);
            vi.setOnLongClickListener(null);
            vi.setLongClickable(false);
            receiptviewholder.shop = (TextView) vi.findViewById(R.id.tv_listitemreceipt_shop);
            receiptviewholder.date = (TextView) vi.findViewById(R.id.tv_listitemreceipt_date);
            receiptviewholder.price = (TextView) vi.findViewById(R.id.tv_listitemreceipt_price);
            receiptviewholder.points = (TextView) vi.findViewById(R.id.tv_listitemreceipt_points);
            receiptviewholder.shop.setTypeface(tf_hn_bold);
            receiptviewholder.price.setTypeface(tf_hn_bold);
            vi.setTag(receiptviewholder);
        }else{//convertview is not null
            receiptviewholder = (ReceiptViewHolder)vi.getTag();
        }

        receiptviewholder.shop.setText(receipt.getShop());
        receiptviewholder.date.setText(dateH.timestampToDateString(Long.parseLong(receipt.getPurchaseDate())));
        receiptviewholder.price.setText("€ "+receipt.getPrice());
        receiptviewholder.points.setText(getPuntenString(receipt));

        vi.setClickable(false);
        return vi;
    }

    public static class ReceiptViewHolder {
        public TextView shop;
        public TextView date;
        public TextView price;
        public TextView points;
    }

    public Object getFilter() {
        // XXX Auto-generated method stub
        return null;
    }

}

---

工作正常，但不是它应该如何工作。

可能尝试刷新您的列表视图：

receiptsListView.invalidate（）

编辑：另一个想法出现在我的脑海里。仅针对记录，尝试禁用列表视图缓存：

---

将您的方法从

public void updateReceiptsList(List<Receipt> newlist) {
    receiptlist = newlist;
    this.notifyDataSetChanged();
}

public void updateReceiptsList（列表新建列表）{
receiptlist=newlist；
this.notifyDataSetChanged（）；
}

到

public void updateReceiptsList（列表新建列表）{
receiptlist.clear（）；
receiptlist.addAll（newlist）；
this.notifyDataSetChanged（）；
}

---

因此，在适配器中保留与数据集相同的对象。

我也有同样的问题，我意识到了这一点。当我们创建适配器并将其设置为listview时，listview将指向适配器所在内存中的某个对象，该对象中的数据将显示在listview中

adapter = new CustomAdapter(data);
listview.setadapter(adapter);

如果我们再次使用另一个数据为适配器创建对象，并通知DataSetChanged（）：

这不会影响listview中的数据，因为列表指向不同的对象，该对象不知道适配器中的新对象，notifyDataSetChanged（）不影响任何内容。

---

因此，我们应该更改对象中的数据，避免再次为适配器创建新对象

我在使用

ListAdapter时遇到同样的问题

我让Android Studio为我实现方法，这就是我得到的：

public class CustomAdapter implements ListAdapter {
    ...
    @Override
    public void registerDataSetObserver(DataSetObserver observer) {

    }

    @Override
    public void unregisterDataSetObserver(DataSetObserver observer) {

    }
    ...
}

问题是这些方法不调用

super

实现，因此从不调用

notifyDataSetChange

要么手动删除这些覆盖，要么添加超级调用，它应该会再次工作

@Override
public void registerDataSetObserver(DataSetObserver observer) {
    super.registerDataSetObserver(observer);
}

@Override
public void unregisterDataSetObserver(DataSetObserver observer) {
    super.unregisterDataSetObserver(observer);
}

---

正如我已经解释了这个问题背后的原因，以及如何在不同的回答线程中处理它。我仍然在这里分享解决方案摘要

notifyDataSetChanged（）

不适合您的主要原因之一是

适配器失去了对列表的引用

在

适配器中创建和添加新列表时

。始终遵循以下准则：

在全局声明时初始化

arrayList

直接将列表添加到适配器，而不检查null和empty 价值观直接将适配器设置到列表中（不检查任何 条件）。适配器保证，无论您在何处 对

arrayList的数据进行更改，它将处理该数据，但不会丢失
参考资料

始终修改arrayList本身中的数据（如果您的数据是全新的 然后可以调用

adapter.clear（）

和

arrayList.clear（）

实际将数据添加到列表中），但不要设置适配器，即如果 新数据填充在

arrayList

中，而不仅仅是

adapter.notifyDataSetChanged（）

---

希望这有帮助。

添加此代码

runOnUiThread(new Runnable() { public void run() {
               adapter = new CustomAdapter(anotherdata);
            adapter.notifyDataSetChanged();
            }
        });

---

如果

adapter

设置为

AutoCompleteTextView

则

notifyDataSetChanged（）

不起作用

需要此更新适配器：

myAutoCompleteAdapter = new ArrayAdapter<String>(MainActivity.this, 
        android.R.layout.simple_dropdown_item_1line, myList);

myAutoComplete.setAdapter(myAutoCompleteAdapter);

myAutoCompleteAdapter=new ArrayAdapter（MainActivity.this，
android.R.layout.simple\u下拉列表\u项目\u 1行，myList）；
设置适配器（myAutoCompleteAdapter）；

请参阅：

class StudentAdapter扩展BaseAdapter{
ArrayList学生名单；
私有无效capNhatDuLieu（ArrayList列表）{
this.studentList.clear（）；
this.studentList.addAll（list）；
this.notifyDataSetChanged（）；
}
}

你可以试试。它对我有用我也有同样的问题 但是我刚刚完成了

你应该换成

公共类ReceiptListAdapter扩展了BaseAdapter{
公共列表接收列表；
私人语境；
私人充气机；
私人约会助手dateH；
私有列表receiptviewlist；
public ReceiptListAdapter（活动、上下文mcontext、列表rl）{
上下文=mcontext；
receiptlist=rl；
receiptviewlist=新建ArrayList（）；
receiptviewlist.clear（）；
对于（int i=0；imyAutoCompleteAdapter = new ArrayAdapter<String>(MainActivity.this, 
        android.R.layout.simple_dropdown_item_1line, myList);

myAutoComplete.setAdapter(myAutoCompleteAdapter);

class StudentAdapter extends BaseAdapter {
    ArrayList<LichHocDTO> studentList;

    private void capNhatDuLieu(ArrayList<LichHocDTO> list){
        this.studentList.clear();
        this.studentList.addAll(list);
        this.notifyDataSetChanged();
    }
}

    // Assuume oneOffJobTasksListRVAdapter is declared already 
    recyclerView.setAdapter(oneOffJobTasksListRVAdapter);        
    oneOffJobTasksListRVAdapter = new OneOffJobTasksListRVAdapter();

    oneOffJobTasksListRVAdapter = new OneOffJobTasksListRVAdapter();
    recyclerView.setAdapter(oneOffJobTasksListRVAdapter);