在我的应用中，我在listview中显示数据。滚动浏览listview时，我的应用程序崩溃了。我应该做些什么改变？
在错误中给出我的RecipeListFragment.java文件是：
public class RecipeListFragment extends Fragment {
MyDatabase db ;
boolean isfav = false;
Context context;
ListView lvrecipe;
ArrayList<RecipePojo> recipelist = new ArrayList<RecipePojo>();
LinearLayout ll;
ImageView fav_unfav;
DisplayImageOptions options;
private ProgressDialog progress;
ImageLoadingListener animateFirstListener = new AnimateFirstDisplayListener();
int counter=8;
int position;
String recipeid;
int checkcounter = 0;
private Custom_Adapter adapter;
public RecipeListFragment() {
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.activity_recipe_list_actvity, container,false);
context=getActivity();
lvrecipe = (ListView)rootView.findViewById(R.id.lvrecipe);
new getrecipe().execute();
db = new MyDatabase(getActivity());
position = DataManager.selectedposition;
adapter = new Custom_Adapter(getActivity());
adapter.notifyDataSetChanged();
lvrecipe.setAdapter(adapter);
lvrecipe.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,int position, long id) {
DataManager.selectedposition = position;
Intent i = new Intent(getActivity(), RecipeDescription.class);
i.putExtra("cusinename", DataManager.cusinename);
startActivity(i);
getActivity().finish();
}
});
return rootView;
}
@Override
public void onResume() {
super.onResume();
}
public class Custom_Adapter extends BaseAdapter {
private LayoutInflater mInflater;
public Custom_Adapter(Context c) {
mInflater = LayoutInflater.from(c);
}
@Override
public int getCount() {
if(recipelist!=null){
return recipelist.size();
}else{
return 0;
}
}
@Override
public Object getItem(int position) {
if(recipelist!=null){
return recipelist.get(position);
}else{
return 0;
}
}
@Override
public long getItemId(int position) {
if(recipelist!=null){
return position;
}else{
return 0;
}
}
@SuppressWarnings("deprecation")
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.recipelist, null);
holder = new ViewHolder();
holder.txttile = (TextView) convertView.findViewById(R.id.txttile);
holder.imgrecipe = (ImageView) convertView.findViewById(R.id.imgrecipe);
holder.fav_unfav = (ImageView) convertView.findViewById(R.id.fav_unfav);
holder.ratingbar = (RatingBar) convertView.findViewById(R.id.ratingbar);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
if(recipelist!=null){
recipeid = recipelist.get(position).getRecipeid();
checkcounter = db.checkrecipefav(recipeid);
}
if(checkcounter > 0) {
isfav = true;
} else {
isfav = false;
}
db.close();
if(isfav){
holder.fav_unfav.setBackgroundDrawable(getResources().getDrawable(R.drawable.favourite));
}
else{
holder.fav_unfav.setBackgroundDrawable(getResources().getDrawable(R.drawable.favourites));
}
Typeface face1 = Typeface.createFromAsset(getActivity().getAssets(),"sinkin_sans_300_light.ttf");
Typeface face2 = Typeface.createFromAsset(getActivity().getAssets(),"sinkin_sans_400_regular.ttf");
holder.txttile.setTypeface(face2);
// holder.txtduration.setTypeface(face1);
holder.txttile.setText(recipelist.get(position).getRecipename());
try{
String [] prep=recipelist.get(position).getPrep_time().split(" ");
String [] cook=recipelist.get(position).getCooking_time().split(" ");
int totalTime=Integer.parseInt(prep[0])+Integer.parseInt(cook[0]);
}catch(NumberFormatException e){
e.printStackTrace();
}catch (Exception e) {
e.printStackTrace();
}
String url = DataManager.photourl+"recipe/"+recipelist.get(position).getRecipeid()+".jpg";
try {
url = URLDecoder.decode(url, "UTF-8");
url = url.replaceAll(" ", "%20");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}catch (Exception e) {
e.printStackTrace();
}
if(recipelist.get(position).getVideo_link().equals("none"))
{
}
String rating = recipelist.get(position).getRatings();
if(rating!=null && rating.trim().length() > 0)
{
holder.ratingbar.setRating(Float.valueOf(rating));
}
if(holder.imgrecipe!=null){
if (url != null && url.trim().length() > 0)
{
final ImageView imageView = holder.imgrecipe;
//final RelativeLayout imgRL = holder.imageRL;
ImageLoader.getInstance().displayImage(url, holder.imgrecipe,options, new SimpleImageLoadingListener()
{
@Override
public void onLoadingComplete(String imageUri,
View view, Bitmap loadedImage)
{
super.onLoadingComplete(imageUri, view, loadedImage);
imageView.setAdjustViewBounds(true);
}
@Override
public void onLoadingFailed(String imageUri, View view,FailReason failReason) {
super.onLoadingFailed(imageUri, view, failReason);
}
@Override
public void onLoadingStarted(String imageUri, View view) {
super.onLoadingStarted(imageUri, view);
}
});
} else {}
}
return convertView;
}
class ViewHolder {
TextView txttile;
ImageView imgrecipe;
ImageView fav_unfav;
RatingBar ratingbar;
}
}
public class getrecipe extends AsyncTask<String, Void, String> {
boolean response = false;
@Override
protected void onPreExecute() {
//progress = ProgressDialog.show(context, "Getting Data...","Please wait....");
progress = new ProgressDialog(getActivity());
progress.setMessage("Please wait....");
progress.show();
}
@Override
protected String doInBackground(String... params) {
response = APIManager.getrecipebycusine(DataManager.CUISINE_ID);
return "";
}
@Override
protected void onPostExecute(String result) {
progress.cancel();
if (response) {
if (DataManager.status.equalsIgnoreCase("1")) {
recipelist = DataManager.recipelist;
adapter.notifyDataSetChanged();
//Intent i = new Intent(getActivity(),RecipeListActvity.class);
//startActivity(i);
} else {
connectionerror();
}
} else {
connectionerror();
}
}
@Override
protected void onProgressUpdate(Void... values) {
}
}
public void alert() {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(getActivity());
alertDialog.setTitle("No Recipe!");
alertDialog.setMessage("No Recipe for this Cusine");
alertDialog.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
}
});
alertDialog.show();
}
private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {
static final List<String> displayedImages = Collections.synchronizedList(new LinkedList<String>());
@Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
if (loadedImage != null) {
ImageView imageView = (ImageView) view;
boolean firstDisplay = !displayedImages.contains(imageUri);
if (firstDisplay) {
FadeInBitmapDisplayer.animate(imageView, 500);
displayedImages.add(imageUri);
}
}
}
}
public void connectionerror() {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(getActivity());
alertDialog.setTitle("Error!");
alertDialog.setMessage("Connection Lost ! Try Again");
alertDialog.setPositiveButton("Retry",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
new getrecipe().execute();
}
});
alertDialog.show();
}
}
Crashlytics中显示的错误是：
Fatal Exception: java.lang.NumberFormatException: Invalid float: ""
at java.lang.StringToReal.invalidReal(StringToReal.java:63)
at java.lang.StringToReal.initialParse(StringToReal.java:176)
at java.lang.StringToReal.parseFloat(StringToReal.java:323)
at java.lang.Float.parseFloat(Float.java:306)
at java.lang.Float.valueOf(Float.java:343)
at com.raccoonfinger.glutenfree.RecipeListFragment$Custom_Adapter.getView(Unknown Source)
at android.widget.AbsListView.obtainView(AbsListView.java:2344)
at android.widget.ListView.makeAndAddView(ListView.java:1864)
at android.widget.ListView.fillDown(ListView.java:698)
at android.widget.ListView.fillGap(ListView.java:662)
at android.widget.AbsListView.trackMotionScroll(AbsListView.java:4968)
at android.widget.AbsListView$FlingRunnable.run(AbsListView.java:4512)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
at android.view.Choreographer.doCallbacks(Choreographer.java:580)
at android.view.Choreographer.doFrame(Choreographer.java:549)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5312)
at java.lang.reflect.Method.invoke(Method.java)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:901)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:696)
答案 0 :(得分：2)
我认为你在Line下面会收到错误。
holder.ratingbar.setRating(Float.valueOf(rating));
这意味着“评级”中的值是字符串，请检查。
答案 1 :(得分：0)
设置评级采用浮点值，例如，ur值为String：
holder.ratingbar.setRating(Float.parseFloat(rating));
答案 2 :(得分：0)
使用parseFloat()
holder.ratingbar.setRating(Float.parseFloat(rating));
取代
holder.ratingbar.setRating(Float.valueOf(rating));
答案 3 :(得分：0)
我不知道你在哪里获得评级的价值。但是它试图将字符串的值解析为抛出错误的Float。
String rating = recipelist.get(position).getRatings();
同时检查字符串是否为空。
// if(rating!=null && rating.trim().length() > 0)
if(rating!=null && !rating.isEmpty() && rating.trim().length() > 0)
{
try{
holder.ratingbar.setRating(Float.valueOf(rating));
}
catch (NumberFormatException e){
// TO DO
}
}
首先检查评级的价值（记录它），如果你在那里得到一个浮动，我建议看一下this answer：
float f = Float.valueOf("> 12.4N-m/kg.".replaceAll("[^\\d.]+|\\.(?!\\d)", ""));
答案 4 :(得分：0)
这个方法的响应应该是float String rating = recipelist.get(position).getRatings();或者要在String中获取它，你必须使用toString();将它转换为String，这就是为什么你得到NumberFormatException