Develop Reference

Java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY when want to get data into recyclerview

I have a json. I have to get source_url into my recyclerView -
[{
"id":3110,
"date":"2020-05-07T18:33:44",
"date_gmt":"2020-05-07T18:33:44",
"modified":"2020-05-07T18:35:37",
"modified_gmt":"2020-05-07T18:35:37",
"_embedded":{
"wp:featuredmedia":[
{
"id":3111,
"date":"2020-05-07T18:33:08",
"slug":"prof-dr-abul-khair",
"source_url":"https:\/\/www.healthmen.com.bd\/wpcontent\/uploads\/2020\/05\/Prof.-Dr.-Abul-Khair-scaled.jpg"
}]
}
}]
I want to get source_url from this JSON
But, here is an array wp:featuredmedia. So that, I followed this process-
Created a class named FeaturedMedia -
public class FeaturedMedia {
#SerializedName("source_url")
#Expose
private String souceurl;
public String getSourceurl(){
return sourceurl;
}
}
Then, I created another class named MediaDetails where I take the FeaturedMedia as a List-
public class MediaDetails{
#SerializedName("wp:featuredmedia")
List<FeaturedMedia> featureMediaList;
public List<FeaturedMedia> getFeaturedMediaList(){
return featuredMediaList;
}}
Then the Model Class-
public class Model{
#SerializedName("id")
#Expose
int id;
#SerializedName("_embedded")
#Expose
MediaDetalis embedded;
public int getId(){
return id;
}
public MediaDetails getEmbedded(){
return embedded;
}}
After all, I created RecyclerViewAdapter to get the data-
public CustomAdapter extends RecyclerView.Adapter<CustomAdapter.CustomAdapterHolder{
List<Model> modelList;
public void onBindViewHolder(#NonNull CustomAdapterHolder holder, int position){
final Model model=modelList.get(position);
int id= model.getId():
String embedded= String.valurOf(model.getEmbedded.getFeaturedMediaList());
}
But, embedded can not get the source_url value. I completed this CustomAdapter. Here I just presented needed code of that adapter. How can I get the source_url value in this RecyclerView?

Your POJO class will be (Respect to given JSON)
public class Model {
#SerializedName("id")
#Expose
private Integer id;
#SerializedName("date")
#Expose
private String date;
#SerializedName("date_gmt")
#Expose
private String dateGmt;
#SerializedName("modified")
#Expose
private String modified;
#SerializedName("modified_gmt")
#Expose
private String modifiedGmt;
#SerializedName("_embedded")
#Expose
private Embedded embedded;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getDateGmt() {
return dateGmt;
}
public void setDateGmt(String dateGmt) {
this.dateGmt = dateGmt;
}
public String getModified() {
return modified;
}
public void setModified(String modified) {
this.modified = modified;
}
public String getModifiedGmt() {
return modifiedGmt;
}
public void setModifiedGmt(String modifiedGmt) {
this.modifiedGmt = modifiedGmt;
}
public Embedded getEmbedded() {
return embedded;
}
public void setEmbedded(Embedded embedded) {
this.embedded = embedded;
}
}
Then Embedded class
public class Embedded {
#SerializedName("wp:featuredmedia")
#Expose
private List<WpFeaturedmedium> wpFeaturedmedia = null;
public List<WpFeaturedmedium> getWpFeaturedmedia() {
return wpFeaturedmedia;
}
public void setWpFeaturedmedia(List<WpFeaturedmedium> wpFeaturedmedia) {
this.wpFeaturedmedia = wpFeaturedmedia;
}
}
Then WpFeaturedmedium
public class WpFeaturedmedium {
#SerializedName("id")
#Expose
private Integer id;
#SerializedName("date")
#Expose
private String date;
#SerializedName("slug")
#Expose
private String slug;
#SerializedName("source_url")
#Expose
private String sourceUrl;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getSlug() {
return slug;
}
public void setSlug(String slug) {
this.slug = slug;
}
public String getSourceUrl() {
return sourceUrl;
}
public void setSourceUrl(String sourceUrl) {
this.sourceUrl = sourceUrl;
}
}
Check - How to create POJO class

add object into GSON array android studio

hey guys im using android's gson library to parse my JSON. everything is working fine in that I have that selected goal array sometimes it is full of values and sometimes it is an empty array. when array is empty I want to push an object init when I try to add its index
selected_goal.add(INDEX,VALUE)
I want to push an object at the place of value please help me how can I do it…
this is my pojo:
public class SelectedGoal {
#SerializedName("id")
#Expose
private String id;
#SerializedName("goal_name")
#Expose
private String goalName;
#SerializedName("image")
#Expose
private String image;
#SerializedName("position")
#Expose
private String position;
#SerializedName("athlete_id")
#Expose
private String athleteId;
#SerializedName("coach_id")
#Expose
private String coachId;
#SerializedName("current_goal_id")
#Expose
private String currentGoalId;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getGoalName() {
return goalName;
}
public void setGoalName(String goalName) {
this.goalName = goalName;
}
public String getImage() {
return image;
}
public void setImage(String image) {
this.image = image;
}
public String getPosition() {
return position;
}
public void setPosition(String position) {
this.position = position;
}
public String getAthleteId() {
return athleteId;
}
public void setAthleteId(String athleteId) {
this.athleteId = athleteId;
}
public String getCoachId() {
return coachId;
}
public void setCoachId(String coachId) {
this.coachId = coachId;
}
public String getCurrentGoalId() {
return currentGoalId;
}
public void setCurrentGoalId(String currentGoalId) {
this.currentGoalId = currentGoalId;
}
}

selected_goal.add(INDEX,new SelectedGoal());
EDIT- To set values, make constuctor in your SelectedGoal class like.
public SelectedGoal(String id, String goalName, String image, String
position, String athleteId, String coachId, String currentGoalId) {
this.id = id;
this.goalName = goalName;
this.image = image;
this.position = position;
this.athleteId = athleteId;
this.coachId = coachId;
this.currentGoalId = currentGoalId;
}
finally add your object into list like..
selected_goal.add(INDEX,new SelectedGoal(id,goalName,image,position,athleteId,coachId,currentGoalId));

How to retrieve a value from list android

I have a list specialties having 75 items that has two values id and name.
private List specialties;
I would like to get the name without using a loop something like below
specialties.get(0).name;
I get an error saying can't resolve name. Is there any way to retrieve name from the values list.
Thanks.

Create a class (Model) to get and set the ID and Name property:-
public class ClassName {
private String id;
private String name;
public ClassName(String mId, String mName){
this.id=mId;
this.name=mName;
}
public String getName() {
return name;
}
public void setName(String sName) {
this.name = sName;
}
public String getId() {
return id;
}
public void setId(String sId) {
this.id = sId;
}
}
In your Activity:-
Define a List having the ClassName type of objects.
List<ClassName> mList = new ArrayList<>();
Now access the property name like this:-
mList.get(0).getName();
mList.get(0).getId();

try the following:
public class Clone {
private int Id;
private String name;
public int getId() {
return Id;
}
public String getName() {
return name;
}
public void setId(int id) {
Id = id;
}
public void setName(String name) {
this.name = name;
}
}
and use
private List<Clone> arrayList = new ArrayList();
for (int i = 0; i < 10; i++) {
Clone helloItem = new Clone();
helloItem.setId(i);
helloItem.setName("I'm Clone no - " + i);
arrayList.add(helloItem);
}
Log.d("check", "get item - " + arrayList.get(0).getName());
hope it help.

I want to suggest you. You should declare name with public access. If it is not public, use public getter and setter method.Call getName() method.
public class YourClass{
private int id;
private String name;
public YourClass(int id, String name) {
this.id = id;
this.name = name;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
private List<YourClass> specialties = new ArrayList<YourClass>;
...//add data into list...
specialties.add(new YourClass( 1 , "John"));
...// retrieve data
specialties.get(position).getName();

You have declared your list as private List specialties; you can not access it like this specialties.get(0).name;
You need declare your list like this private List<YourModelClass> specialties;
SAMPLE DEMO
If you want add model class in your list than than check this example
create model class like this
public class User {
String name, email;
public User(String name, String email) {
this.name = name;
this.email = email;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
}
Now use like this in your list
List<User> userArrayList= new ArrayList<>();
To add data inside list like this
userArrayList.add(new User("Nilesh","abc#gmail.com"));
To get data from your list use like this
userArrayList.get(0).getEmail();
userArrayList.get(0).getEmail();
or
for (int i=0;i<userArrayList.size();i++){
userArrayList.get(i).getName();
userArrayList.get(i).getEmail();
}

Professional way to handle model classes when using GSON and SQLight Android app

In My application I get data from a web service and display those data in recycler view. After that I'm planing to add those data in to local sqlite database and display those data when user open application without internet connection.
Here's a simple model class I'm using to pars JSON result using GSON
public class Repo implements Parcelable {
#SerializedName("id")
#Expose
private Integer id;
#SerializedName("name")
#Expose
private String name;
#SerializedName("url")
#Expose
private String url;
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeValue(this.id);
dest.writeString(this.name);
dest.writeString(this.url);
}
public Repo() {
}
protected Repo(Parcel in) {
this.id = (Integer) in.readValue(Integer.class.getClassLoader());
this.name = in.readString();
this.url = in.readString();
}
public Integer getId() {
return id;
}
public String getName() {
return name;
}
public String getUrl() {
return url;
}
public void setId(Integer id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setUrl(String url) {
this.url = url;
}
public static final Creator<Repo> CREATOR = new Creator<Repo>() {
#Override
public Repo createFromParcel(Parcel source) {
return new Repo(source);
}
#Override
public Repo[] newArray(int size) {
return new Repo[size];
}
};
}
I can create a almost identical model class to represent SQLite data. In here I'm using ORMlite. But this is very similar situation for other ORMs.
#DatabaseTable(tableName = Repo.TABLE_NAME)
public class Repo {
public static final String TABLE_NAME = "repo";
#DatabaseField(columnName = "repo_id")
private long repoId;
#DatabaseField(columnName = "name")
private String name;
public long getRepoId() {
return repoId;
}
public String getName() {
return name;
}
public void setRepoId(long repoId) {
this.repoId = repoId;
}
public void setName(String name) {
this.name = name;
}
}
But by the time I'm trying to save these data in to SQLite database I already have data objects set in GSON model classes. It's kind a redundant thing copy object from GSON model and setting that values in to SQLite model. So I came up with below solution by trying to use single model class to represent both.
#DatabaseTable(tableName = Repo.TABLE_NAME)
public class Repo implements Parcelable {
public static final String TABLE_NAME = "repo";
#DatabaseField(columnName = "repo_id")
#SerializedName("id")
#Expose
private Integer id;
#DatabaseField(columnName = "name")
#SerializedName("name")
#Expose
private String name;
#SerializedName("url")
#Expose
private String url;
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeValue(this.id);
dest.writeString(this.name);
dest.writeString(this.url);
}
public Repo() {
}
protected Repo(Parcel in) {
this.id = (Integer) in.readValue(Integer.class.getClassLoader());
this.name = in.readString();
this.url = in.readString();
}
public Integer getId() {
return id;
}
public String getName() {
return name;
}
public String getUrl() {
return url;
}
public void setId(Integer id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setUrl(String url) {
this.url = url;
}
public static final Creator<Repo> CREATOR = new Creator<Repo>() {
#Override
public Repo createFromParcel(Parcel source) {
return new Repo(source);
}
#Override
public Repo[] newArray(int size) {
return new Repo[size];
}
};
}
I have try this with different type of model class where it only had String type fields. Since GSON uses types like Integer,Boolean That stopping me from using same model for SQLite because database does not identify Integer as a type, in order to work it need to be int.
So what is the professional way to handle this ? Don't I have any other option other than going back to the method of creating two separate model class to represent SQLite and GSON.

Yout approach is absolutely correct, but i think you are putting too much effort reinventing the wheel
You can easily achieve the described task using Room

How to be with identical in content classes using by Realm

I need to create many identical in content classes like the class below
public abstract class AbstractListModel extends RealmObject {
#PrimaryKey
private String id;
private String name;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
If I will extend this class in another, it seems I'll have a lot of empty classes, 'cause they have only 2 fields (id and name) wich contains in the mother-class.
public class LectureHallListModel extends AbstractListModel {
//#PrimaryKey
//private String id;
//private String name;
//public String getId() {
// return id;
//}
//public void setId(String id) {
// this.id = id;
//}
//public String getName() {
// return name;
//}
//public void setName(String name) {
// this.name = name;
//}
}
Are the any way to add to a DB several identical in content tables without creation empty classes?Thank you!

Inheritance of fields (technically from any class that is not directly RealmObject) is not supported by Realm.
You would need the following setup:
public interface AbstractListModel {
String getId();
void setId(String id);
String getName();
void setName(String name);
}
And
public class LectureHallListModel extends RealmObject implements AbstractListModel {
#PrimaryKey
private String id;
private String name;
#Override
public String getId() {
return id;
}
#Override
public void setId(String id) {
this.id = id;
}
#Override
public String getName() {
return name;
}
#Override
public void setName(String name) {
this.name = name;
}
}