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Java 如何使用自定义列表适配器检查ListView是否为空_Java_Android_Sqlite_Listview_Baseadapter - Fatal编程技术网

Java 如何使用自定义列表适配器检查ListView是否为空

Java 如何使用自定义列表适配器检查ListView是否为空,java,android,sqlite,listview,baseadapter,Java,Android,Sqlite,Listview,Baseadapter,我在我的应用程序中使用了两个Adpater,一个用于脱机模式,从本地sqlite DB获取数据。第二个适配器从服务器获取数据,并在listview中显示两个适配器共有的项。在列表中没有数据的情况下,我使用空视图显示列表为空。但即使sqlite中有数据,它仍然会显示空列表。我想知道有没有办法检查适配器是否为空。如果它不为null,则表示它应该显示列表中的值 脱机适配器: public class ImageListAdapter extends BaseAdapter { Context

我在我的应用程序中使用了两个Adpater,一个用于脱机模式,从本地sqlite DB获取数据。第二个适配器从服务器获取数据,并在listview中显示两个适配器共有的项。在列表中没有数据的情况下,我使用空视图显示列表为空。但即使sqlite中有数据,它仍然会显示空列表。我想知道有没有办法检查适配器是否为空。如果它不为null,则表示它应该显示列表中的值

脱机适配器:

public class ImageListAdapter extends BaseAdapter {
    Context context;
    ArrayList<ImagelistItems> imageList;

    public ImageListAdapter(Context context, ArrayList<ImagelistItems> list) {

        this.context = context;
        imageList = list;
    }


    @Override
    public int getCount() {

        return imageList.size();
    }

    @Override
    public Object getItem(int position) {

        return imageList.get(position);
    }

    @Override
    public long getItemId(int position) {

        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup arg2) {
        ImagelistItems imagelistItems = imageList.get(position);

        if (convertView == null) {
            LayoutInflater inflater = (LayoutInflater) context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.imagelist_items, null);

        }
        byte[] outImage = imagelistItems.getImage();
        ByteArrayInputStream imageStream = new ByteArrayInputStream(outImage);
        final Bitmap theImage = BitmapFactory.decodeStream(imageStream);
        ImageView img = (ImageView) convertView.findViewById(R.id.imgview);
        img.setImageBitmap(theImage);
        final TextView merchname = (TextView) convertView.findViewById(R.id.lsmerchantname);
        merchname.setText(imagelistItems.getMerchantname());
        final TextView paid = (TextView) convertView.findViewById(R.id.lspaiddate);
        paid.setText(imagelistItems.getPaidon());
        TextView status = (TextView) convertView.findViewById(R.id.lsstatus);
        status.setText(imagelistItems.getStatus());
        final TextView amt = (TextView) convertView.findViewById(R.id.lsamount);
        amt.setText(imagelistItems.getAmount());
        ImageButton oofbutton = (ImageButton) convertView.findViewById(R.id.btnofflinebutton);
        oofbutton.setVisibility(View.INVISIBLE);
        final TextView category = (TextView) convertView.findViewById(R.id.lscategory);
        category.setText(imagelistItems.getCategory());
        final TextView paymode = (TextView) convertView.findViewById(R.id.lspaidwith);
        paymode.setText(imagelistItems.getPaymmode());
        final TextView comment = (TextView) convertView.findViewById(R.id.lscomment);
        comment.setText(imagelistItems.getComment());
        final TextView moneydet = (TextView) convertView.findViewById(R.id.moneydetails);
        final String moen;
        CurrenctSession currenctSession = new CurrenctSession(context);
        if (currenctSession.isLoggedIn()) {
            HashMap<String, String> cur = currenctSession.getUserDetails();
            moen = cur.get(currenctSession.KEY_CURRENCY);
            moneydet.setText(moen);
        } else {
            moneydet.setVisibility(View.INVISIBLE);
        }
        convertView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String am = amt.getText().toString();
                if (am.contains("km") | am.contains("m")) {
                    Intent i = new Intent(context, MapsDetailPage.class);
                    i.putExtra("distance", amt.getText().toString());
                    i.putExtra("origin", merchname.getText().toString());
                    i.putExtra("dest", paymode.getText().toString());
                    i.putExtra("catg", category.getText().toString());
                    i.putExtra("pdate", paid.getText().toString());
                    i.putExtra("comm", comment.getText().toString());
                    context.startActivity(i);
                } else {
                    Intent i = new Intent(context, DetailsPage.class);
                    i.putExtra("bitmap", theImage);
                    i.putExtra("amount", amt.getText().toString());
                    i.putExtra("mername", merchname.getText().toString());
                    i.putExtra("paidon", paid.getText().toString());
                    i.putExtra("catg", category.getText().toString());
                    i.putExtra("paym", paymode.getText().toString());
                    i.putExtra("comm", comment.getText().toString());
                    context.startActivity(i);
                }

            }
        });
        return convertView;

    }
}
公共类ImageListAdapter扩展了BaseAdapter{
语境;
ArrayList图像列表;
公共ImageListAdapter(上下文,ArrayList列表){
this.context=上下文;
imageList=列表;
}
@凌驾
public int getCount(){
返回imageList.size();
}
@凌驾
公共对象getItem(int位置){
返回imageList.get(位置);
}
@凌驾
公共长getItemId(int位置){
返回位置;
}
@凌驾
公共视图getView(int位置、视图转换视图、视图组arg2){
ImagelistItems ImagelistItems=imageList.get(位置);
if(convertView==null){
LayoutFlater充气器=(LayoutFlater)上下文
.getSystemService(上下文布局\充气机\服务);
convertView=充气机。充气(R.layout.imagelist_项,空);
}
字节[]outImage=imagelistItems.getImage();
ByteArrayInputStream imageStream=新的ByteArrayInputStream(outImage);
最终位图theImage=BitmapFactory.decodeStream(图像流);
ImageView img=(ImageView)convertView.findViewById(R.id.imgview);
设置图像位图(图像);
final TextView merchname=(TextView)convertView.findViewById(R.id.lsmerchantname);
merchname.setText(imagelistItems.getMerchantname());
final TextView paid=(TextView)convertView.findViewById(R.id.lspaiddate);
paid.setText(imagelistItems.getPaidon());
TextView状态=(TextView)convertView.findViewById(R.id.lsstatus);
status.setText(imagelistItems.getStatus());
最终文本视图金额=(文本视图)convertView.findViewById(R.id.lsamount);
amt.setText(imagelistItems.getAmount());
ImageButton oofbutton=(ImageButton)convertView.findViewById(R.id.btnofflinebutton);
oofbutton.setVisibility(View.INVISIBLE);
最终TextView类别=(TextView)convertView.findViewById(R.id.lscategory);
category.setText(imagelistItems.getCategory());
final TextView paymode=(TextView)convertView.findViewById(R.id.lspaidwith);
setText(imagelistItems.getPaymmode());
最终文本视图注释=(文本视图)convertView.findViewById(R.id.lscomment);
setText(imagelistItems.getComment());
final TextView moneydet=(TextView)convertView.findViewById(R.id.moneydetails);
最后一串moen;
CurrenctSession CurrenctSession=新的CurrenctSession(上下文);
if(currenctSession.isLoggedIn()){
HashMap cur=currenctSession.getUserDetails();
moen=当前获取(currenctSession.KEY\u CURRENCY);
moneydet.setText(moen);
}否则{
moneydet.setVisibility(视图不可见);
}
convertView.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图){
字符串am=amt.getText().toString();
如果(上午包含(“km”)|上午包含(“m”)){
意图i=新意图(上下文,MapsDetailPage.class);
i、 putExtra(“距离”,amt.getText().toString());
i、 putExtra(“origin”,merchname.getText().toString());
i、 putExtra(“dest”,paymode.getText().toString());
i、 putExtra(“catg”,category.getText().toString());
i、 putExtra(“pdate”,paid.getText().toString());
i、 putExtra(“comm”,comment.getText().toString());
背景。起始触觉(i);
}否则{
意图i=新意图(上下文,DetailsPage.class);
i、 putExtra(“位图”,图像);
i、 putExtra(“金额”,amt.getText().toString());
i、 putExtra(“mername”,merchname.getText().toString());
i、 putExtra(“paidon”,paid.getText().toString());
i、 putExtra(“catg”,category.getText().toString());
i、 putExtra(“paym”,paymode.getText().toString());
i、 putExtra(“comm”,comment.getText().toString());
背景。起始触觉(i);
}
}
});
返回视图;
}
}
联机适配器:

public class CustomlistJsonadapter extends BaseAdapter {

    private Activity activity;
    private LayoutInflater inflater;
    private List<ReceiptMov> movieItems;


    public CustomlistJsonadapter(Activity activity, List<ReceiptMov> movieItems) {
        this.activity = activity;
        this.movieItems = movieItems;
    }

    @Override
    public int getCount() {
        return movieItems.size();
    }

    @Override
    public Object getItem(int location) {
        return movieItems.get(location);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

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

        if (inflater == null)
            inflater = (LayoutInflater) activity
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (convertView == null)
            convertView = inflater.inflate(R.layout.onlineimagelist_items, null);

        final TextView merchantname = (TextView) convertView.findViewById(R.id.olsmerchantname);
        final TextView paiddate = (TextView) convertView.findViewById(R.id.olspaiddate);
        final TextView amounts = (TextView) convertView.findViewById(R.id.olsamount);
        final TextView paidwith = (TextView) convertView.findViewById(R.id.olspaidwith);
        final TextView categ = (TextView) convertView.findViewById(R.id.olscategory);
        final TextView comment = (TextView) convertView.findViewById(R.id.olscomment);
        final TextView stast = (TextView) convertView.findViewById(R.id.olsstatus);

        ImageView imgview = (ImageView) convertView.findViewById(R.id.oimgview);
        ReceiptMov m = movieItems.get(position);


        // Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
        byte[] s = m.getMimage();
        ByteArrayInputStream imageStream = new ByteArrayInputStream(s);
        final Bitmap theImage = BitmapFactory.decodeStream(imageStream);
        // Bitmap bm = BitmapFactory.decodeByteArray(s, 0 ,s.length);

        imgview.setImageBitmap(theImage);
        merchantname.setText(m.getMerchantname());
        paiddate.setText("Paid on:" + m.getMerdate());
        amounts.setText(m.getMeramount());
        paidwith.setText(m.getMerpaid());
        categ.setText(m.getMercategory());
        comment.setText(m.getMecomment());
        stast.setText("Status: " + "Uploaded");
        final TextView moneydet = (TextView) convertView.findViewById(R.id.omoneydetails);
        final String moen;
        CurrenctSession currenctSession = new CurrenctSession(activity);
        if (currenctSession.isLoggedIn()) {
            HashMap<String, String> cur = currenctSession.getUserDetails();
            moen = cur.get(currenctSession.KEY_CURRENCY);
            moneydet.setText(moen);
        } else {
            moneydet.setVisibility(View.INVISIBLE);
        }
        convertView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String am = amounts.getText().toString();
                if (am.contains("km") | am.contains("m")) {
                    Intent i = new Intent(activity, MapsDetailPage.class);
                    i.putExtra("distance", amounts.getText().toString());
                    i.putExtra("origin", merchantname.getText().toString());
                    i.putExtra("dest", paidwith.getText().toString());
                    i.putExtra("catg", categ.getText().toString());
                    i.putExtra("pdate", paiddate.getText().toString());
                    i.putExtra("comm", comment.getText().toString());
                    activity.startActivity(i);
                } else {
                    Intent i = new Intent(activity, DetailsPage.class);
                    i.putExtra("bitmap", theImage);
                    i.putExtra("amount", amounts.getText().toString());
                    i.putExtra("mername", merchantname.getText().toString());
                    i.putExtra("paidon", paiddate.getText().toString());
                    i.putExtra("catg", categ.getText().toString());
                    i.putExtra("paym", paidwith.getText().toString());
                    i.putExtra("comm", comment.getText().toString());
                    activity.startActivity(i);
                }

            }
        });

        return convertView;
    }
}
公共类CustomlistJsonadapter扩展了BaseAdapter{
私人活动;
私人充气机;
私人电影项目清单;
公共CustomlistJsonadapter(活动,列出电影项目){
这个。活动=活动;
this.movieItems=movieItems;
}
@凌驾
public int getCount(){
返回movieItems.size();
}
@凌驾
公共对象getItem(int位置){
返回电影项目。获取(位置);
}
@凌驾
公共长getItemId(int位置){
返回位置;
}
@凌驾
公共视图getView(int位置、视图转换视图、视图组父视图){
如果(充气器==null)
充气器=(充气器)活动
.getSystemService(上下文布局\充气机\服务);
if(convertView==null)
convertView=充气机。充气(R.layout.onlineimagelist_项,空);
最终文本视图商品名称=(文本视图)convertView.findViewById(R.id.ol
if(imageListAdapter!=null){
        DatabaseHandler db = new DatabaseHandler(getApplicationContext());

        // Spinner Drop down elements
        //  List<String> lables = db.getAllLabels();
        ArrayList<ImagelistItems> list = new ArrayList<ImagelistItems>();
        list = db.getAllLabels();
        imageListAdapter = new ImageListAdapter(
                ListMode.this, list);
        if (loginSession.isLoggedIn()) {
            loginSession.checkLogin();
            listView.setAdapter(imageListAdapter);
           // listView.setEmptyView(findViewById(R.id.empty));

            Toast.makeText(getApplicationContext(), db.getSyncStatus(), Toast.LENGTH_LONG).show();
        } else {
            Intent i = new Intent(ListMode.this, LoginPAge.class);
            startActivity(i);
            ListMode.this.finish();
        }

    }else{
        listView.setEmptyView(findViewById(R.id.empty));
    }
if(adapter.getCount()>0)
{
//some rows of listview
}
else
{
//listview is empty
}
    ImageListAdapter imageListAdapter= new ImageListAdapter();
    listviewObject.setAdapter(imageListAdapter);

    if (imageListAdapter!= null)
        if (imageListAdapter.getCount() > 0){
            // implement your work
        }else {
            // do whatever you want on empty list adapter 
        }
if (adapter!=null) {
    if (adapter.getCount() > 0) {
        // listView not empty
    } else {
        // listView  empty
    }
}
TextView empty = (TextView) findViewById(android.R.id.empty);
listView.setEmptyView(empty);
listView.setAdapter(adapter);
list_view.setAdapter(adapter);
if (adapter.getCount() > 0) {

} else {
  Toast.makeText(getApplicationContext(), "NO Data Available..", Toast.LENGTH_SHORT).show();
}
 if(mAdapter.getItemCount()==0)
            {
                Toast.makeText(UpdatePorder.this, "list is filled", Toast.LENGTH_SHORT).show();
            }
            else
            {
               Toast.makeText(UpdatePorder.this, "List is empty", Toast.LENGTH_SHORT).show();
            }