How to reuse the Parcelable object in Android? - android

I have the class that implements Parcelable interface. That contain HashMap, this HashMap contains bitmap images. I need this HashMap for all my activities. So I used Parcelable. Look on my Parcelable code.
private HashMap<String, Bitmap> map;
public ParcelFullData() {
map = new HashMap();
}
public ParcelFullData(Parcel in) {
map = new HashMap();
readFromParcel(in);
}
public static final Parcelable.Creator CREATOR = new Parcelable.Creator() {
public ParcelFullData createFromParcel(Parcel in) {
return new ParcelFullData(in);
}
public ParcelFullData[] newArray(int size) {
return new ParcelFullData[size];
}
};
public int describeContents() {
return 0;
}
public void writeToParcel(Parcel dest, int flags) {
dest.writeInt(map.size());
for (String s: map.keySet()) {
dest.writeString(s);
dest.writeValue(map.get(s));
}
}
public void readFromParcel(Parcel in) {
int count = in.readInt();
for (int i = 0; i < count; i++) {
map.put(in.readString(), (Bitmap)in.readValue(Bitmap.class.getClassLoader()));
}
}
public Bitmap get(String key) {
return map.get(key);
}
public String[] getKeys() {
Set<String> mapset = map.keySet();
String[] photoName = new String[mapset.size()];
Iterator<String> itr = mapset.iterator();
int index = 0;
while (itr.hasNext()) {
String name = itr.next();
photoName[index] = name;
index++;
}
return photoName;
}
public void put(String key, Bitmap value) {
map.put(key, value);
}
public HashMap<String, Bitmap> getHashMap() {
return map;
}
This will working fine when i pass the one Activity to another Activity.( For example Activity A to Activity B.) But If I pass this to another Activity( For example Activity B to Activity C.) means that HashMap contains no elements. That size is 0.
In Activity_A,
Intent setIntent = new Intent(activity_a, Activity_B.class);
ParcelFullData parcelData = new ParcelFullData();
Bundle b = new Bundle();
b.putParcelable("parcelData", parcelData);
startActivity(setIntent);
In Activity_B
ParcelFullData parcelData = (ParcelFullData)bundle.getParcelable("parcelData");
Parcel parcel = Parcel.obtain();
parcel.writeParcelable(parcelData , 0);
parcelData.writeToParcel(parcel, 0);
Intent setIntent = new Intent(activity_a, Activity_B.class);
Bundle b = new Bundle();
b.putParcelable("parcelData", parcelData);
startActivity(setIntent);
I'm doing the same in Activity C.
How to use resolve this?

Why do you use bundle? You don't add this bundle to intent. Use Intent.putExtra(String, Parcelable) and everything will be OK. I pass one Parcelable object through all activities in my app and it works fine.
In first activity:
Intent i = new Intent(activity_a, Activity_B.class);
i.putExtra("parcelData", parcelData);
In second activity:
parcelData = getIntent().getParcelableExtra("parcelData");
// ... do anything with parcelData here
Intent i = new Intent(activity_b, Activity_C.class);
i.putExtra("parcelData", parcelData);

Related

Unmarshalling unknown type code XXXXX at offset YYY when using getIntent().getExtras().getInt() [duplicate]

This question already has answers here:
java.lang.RuntimeException: Parcel android.os.Parcel: Unmarshalling unknown type code
(2 answers)
Closed 5 years ago.
I'm trying to pass an int value from activity A to activity B.
Activity A:
Intent intent = new Intent(ActivityA.this, ActivityB.class);
intent.putExtra("list_size", list.size());
for (int i = 0; i < list.size(); i++) {
intent.putExtra("account" + i, accountList.get(i));
}
startActivityForResult(intent, 2);
Activity B:
private void init() {
Intent intent = getIntent();
int listSize = intent.getIntExtra("list_size", 0); // Error thrown here
for (int i = 0; i < listSize; i++) {
newList.add((Account) intent.getParcelableExtra("account" + i));
}
}
Account (this is the list item):
public class Account implements Parcelable {
private Long accountId;
private String accountName;
private Set<String> followedAccountsIds = new HashSet<>();
private Set<String> followersAccountsIds = new HashSet<>();
private Set<Integer> likedTagsIds = new HashSet<>();
private Set<Post> postsByAccount = new HashSet<>();
public Account() {
}
public Account(Long accountId, String accountName, Set<String> followedAccountsIds,
Set<String> followersAccountsIds, Set<Integer> likedTagsIds, Set<Post> postsByAccount) {
this.accountId = accountId;
this.accountName = accountName;
this.followedAccountsIds = followedAccountsIds;
this.followersAccountsIds = followersAccountsIds;
this.likedTagsIds = likedTagsIds;
this.postsByAccount = postsByAccount;
}
// Omitted getters and setters for brevity
protected Account(Parcel in) {
if (in.readByte() == 0) {
accountId = null;
} else {
accountId = in.readLong();
}
accountName = in.readString();
}
public static final Creator<Account> CREATOR = new Creator<Account>() {
#Override
public Account createFromParcel(Parcel in) {
return new Account(in);
}
#Override
public Account[] newArray(int size) {
return new Account[size];
}
};
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel parcel, int i) {
parcel.writeLong(accountId);
parcel.writeString(accountName);
}
}
Error that is thrown:
Caused by: java.lang.RuntimeException: Parcel android.os.Parcel#8b4252e: Unmarshalling unknown type code 6357091 at offset 140
at android.os.Parcel.readValue(Parcel.java:2453)
at android.os.Parcel.readArrayMapInternal(Parcel.java:2727)
at android.os.BaseBundle.unparcel(BaseBundle.java:269)
at android.os.BaseBundle.getInt(BaseBundle.java:867)
at android.content.Intent.getIntExtra(Intent.java:6637)
at com.david.songshareandroid.activities.ActivityB.init(ActivityB.java:33)
at com.david.songshareandroid.activities.ActivityB.onCreate(ActivityB.java:28)
at android.app.Activity.performCreate(Activity.java:6912)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1126)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2877)
In ActivityB when intent.getIntExtra("list_size", 0) is invoked, the error above occurs. If I remove the for loop in ActivityA, that is the objects are not getting passed to ActivityB, then the error does not occur anymore.
You are putting something but getting something else.
You are putting an Int
intent.putExtra("list_size", list.size());
Now on Target Activity do this:
Intent intent = getIntent();
int number = intent.getIntExtra("list_size",0);
and your SomeObject class must implement Parceable interface
First you taking Bundle Extras using intent.getExtras() which returns you bundle object which contains key-value pairs, and then you trying to find pair with key list_size which is not in there. So you should use intent.getIntExtra() instead.
UPD
I don't think that your parcel implementation should work because of Sets. Use Set.toArray() method, then in Parcel.writeTypedArray write it to the parcel.

Parcelable creation from a bundle does not call constructor

I have a class that implements Parcelable.
I safe this object to the bundle in an activites onSaveInstanceState and I try to recreate the object in onCreate. This looks like following:
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
if (savedInstanceState != null)
{
// this line does NOT call my constructor, why not?
// AND I don't get the same object as before => I get an uninitialised object
mStackManager = savedInstanceState.getParcelable(BackstackManager.TAG);
// the list and map in the object are NULL after this...
}
else
{
mStackManager = new BackstackManager();
...
}
}
#Override
public void onSaveInstanceState(Bundle outState)
{
super.onSaveInstanceState(outState);
outState.putParcelable(BackstackManager.TAG, mStackManager);
}
When the Parcelable class is created, it should call the cosntructor of the parcelable class, shouldn't it? My parcelable class is retrieved from the bundle, but it does not look like the object that was saved, it even is not initialised...
My simplified parcelable class looks like following:
public class BackstackManager implements Parcelable
{
public static final String TAG = BackstackManager.class.getName();
private List<List<Pair<Class<?>, Pair<Integer, String>>>> mBackstack;
private Map<String, Fragment.SavedState> mSavedStateMap;
public BackstackManager()
{
init();
}
private void init()
{
mBackstack = new ArrayList<List<Pair<Class<?>, Pair<Integer, String>>>>();
mSavedStateMap = new HashMap<String, Fragment.SavedState>();
}
// ----------------------
// Parcelable
// ----------------------
public static final Parcelable.Creator<BackstackManager> CREATOR =
new Parcelable.Creator<BackstackManager>()
{
#Override
public BackstackManager createFromParcel(Parcel source)
{
return new BackstackManager(source);
}
#Override
public BackstackManager[] newArray(int size)
{
return new BackstackManager[size];
}
};
public BackstackManager(Parcel source)
{
init();
readFromParcel(source);
}
#Override
public int describeContents()
{
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags)
{
dest.writeInt(mBackstack.size());
for (int i = 0; i < mBackstack.size(); i++)
{
List<Pair<Class<?>, Pair<Integer, String>>> data = mBackstack.get(i);
dest.writeInt(data.size());
for (int j = 0; j < data.size(); j++)
{
Class<?> clazz = data.get(j).first;
Integer id = data.get(j).second.first;
String tag = data.get(j).second.second;
Fragment f = mFragmentManager.findFragmentByTag(tag);
// 1) save backstack data
ParcelBundleUtils.writeStringNullSafe(dest, clazz != null ? clazz.getName() : null);
dest.writeInt(id);
dest.writeString(tag);
// 2) save fragment state, if possible
ParcelBundleUtils.writeBoolean(dest, f != null);
if (f != null)
ParcelBundleUtils.writeParcelableNullSafe(dest, mFragmentManager.saveFragmentInstanceState(f), 0);
}
}
}
public void readFromParcel(Parcel source)
{
int backstackSize = source.readInt();
for (int i = 0; i < backstackSize; i++)
{
ArrayList<Pair<Class<?>, Pair<Integer, String>>> data = new ArrayList<Pair<Class<?>, Pair<Integer, String>>>();
int dataSize = source.readInt();
for (int j = 0; j < dataSize; j++)
{
// 1) read backstack data
String clazzName = ParcelBundleUtils.readStringNullSafe(source);
Class<?> clazz = null;
if (clazzName != null)
{
try
{
clazz = Class.forName(clazzName);
}
catch (ClassNotFoundException e)
{
L.e(this, e);
}
}
Integer id = source.readInt();
String tag = source.readString();
// 2) read fragment state if possible
boolean savedStateExists = ParcelBundleUtils.readBoolean(source);
if (savedStateExists)
{
SavedState state = ParcelBundleUtils.readParcelableNullSafe(source, SavedState.class.getClassLoader());
if (state != null)
mSavedStateMap.put(tag, state);
}
data.add(new Pair<Class<?>, Pair<Integer, String>>(clazz, new Pair<Integer, String>(id, tag)));
}
mBackstack.add(data);
}
}
}
My ParcelBundleUtils just write a bit if an object is null or not and dependent on that read/write the actual object...
EDIT
my current workround is to use a read/write function for a bundle that does EXACTLY (I copy and pasted my code and just replaced the read/write functions) the same as the parcel read/write function, but writes the data directly to a bundle... But I really would like to know, why the above is not working as a parcel
EDIT 2
I found following: Android: Parcelable.writeToParcel and Parcelable.Creator.createFromParcel are never called
But if that's the problem, I would not be the only one facing this problem...
You must have the following line as the first line in your onCreate(Bundle) override:
super.onCreate(savedInstanceState);
This is why your state is not working correctly.

How to pass ArrayList<CustomeObject> from one activity to another? [duplicate]

This question already has answers here:
Passing arraylist of objects between activities
(6 answers)
Passing a List from one Activity to another
(6 answers)
Closed 9 years ago.
I want to send Following ArrayList from one activity to another please help.
ContactBean m_objUserDetails = new ContactBean();
ArrayList<ContactBean> ContactLis = new ArrayList<ContactBean>();
I am sending the above arraylist after adding data in it as follows
Intent i = new Intent(this,DisplayContact.class);
i.putExtra("Contact_list", ContactLis);
startActivity(i);
But I am getting problem while recovering it.
ArrayList<ContactBean> l1 = new ArrayList<ContactBean>();
Bundle wrapedReceivedList = getIntent().getExtras();
l1= wrapedReceivedList.getCharSequenceArrayList("Contact_list");
At this point I am getting this error:
Type mismatch: cannot convert from ArrayList<CharSequence> to ArrayList<ContactBean>
My ContactBean class implements Serializable please also tell why we have to implement serializable interface.
In First activity:
ArrayList<ContactBean> fileList = new ArrayList<ContactBean>();
Intent intent = new Intent(MainActivity.this, secondActivity.class);
intent.putExtra("FILES_TO_SEND", fileList);
startActivity(intent);
In receiver activity:
ArrayList<ContactBean> filelist = (ArrayList<ContactBean>)getIntent().getSerializableExtra("FILES_TO_SEND");`
you need implements Parcelable in your ContactBean class, I put one example for you:
public class ContactClass implements Parcelable {
private String id;
private String photo;
private String firstname;
private String lastname;
public ContactClass()
{
}
private ContactClass(Parcel in) {
firstname = in.readString();
lastname = in.readString();
photo = in.readString();
id = in.readString();
}
#Override
public int describeContents() {
// TODO Auto-generated method stub
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(firstname);
dest.writeString(lastname);
dest.writeString(photo);
dest.writeString(id);
}
public static final Parcelable.Creator<ContactClass> CREATOR = new Parcelable.Creator<ContactClass>() {
public ContactClass createFromParcel(Parcel in) {
return new ContactClass(in);
}
public ContactClass[] newArray(int size) {
return new ContactClass[size];
}
};
// all get , set method
}
and this get and set for your code:
Intent intent = new Intent(this,DisplayContact.class);
intent.putExtra("Contact_list", ContactLis);
startActivity(intent);
second class:
ArrayList<ContactClass> myList = getIntent().getParcelableExtra("Contact_list");
Use this code to pass arraylist<customobj> to anthother Activity
firstly serialize our contact bean
public class ContactBean implements Serializable {
//do intialization here
}
Now pass your arraylist
Intent intent = new Intent(this,name of activity.class);
contactBean=(ConactBean)_arraylist.get(position);
intent.putExtra("contactBeanObj",conactBean);
_activity.startActivity(intent);

How to pass ArrayList of Objects from one to another activity using Intent in android?

I have the following in code in my onClick() method as
List<Question> mQuestionsList = QuestionBank.getQuestions();
Now I have the intent after this line, as follows :
Intent resultIntent = new Intent(this, ResultActivity.class);
resultIntent.putParcelableArrayListExtra("QuestionsExtra", (ArrayList<? extends Parcelable>) mQuestionsList);
startActivity(resultIntent);
I don't know how to pass this question lists in the intent from one activity to another activity
My Question class
public class Question {
private int[] operands;
private int[] choices;
private int userAnswerIndex;
public Question(int[] operands, int[] choices) {
this.operands = operands;
this.choices = choices;
this.userAnswerIndex = -1;
}
public int[] getChoices() {
return choices;
}
public void setChoices(int[] choices) {
this.choices = choices;
}
public int[] getOperands() {
return operands;
}
public void setOperands(int[] operands) {
this.operands = operands;
}
public int getUserAnswerIndex() {
return userAnswerIndex;
}
public void setUserAnswerIndex(int userAnswerIndex) {
this.userAnswerIndex = userAnswerIndex;
}
public int getAnswer() {
int answer = 0;
for (int operand : operands) {
answer += operand;
}
return answer;
}
public boolean isCorrect() {
return getAnswer() == choices[this.userAnswerIndex];
}
public boolean hasAnswered() {
return userAnswerIndex != -1;
}
#Override
public String toString() {
StringBuilder builder = new StringBuilder();
// Question
builder.append("Question: ");
for(int operand : operands) {
builder.append(String.format("%d ", operand));
}
builder.append(System.getProperty("line.separator"));
// Choices
int answer = getAnswer();
for (int choice : choices) {
if (choice == answer) {
builder.append(String.format("%d (A) ", choice));
} else {
builder.append(String.format("%d ", choice));
}
}
return builder.toString();
}
}
Between Activity: Worked for me
ArrayList<Object> object = new ArrayList<Object>();
Intent intent = new Intent(Current.class, Transfer.class);
Bundle args = new Bundle();
args.putSerializable("ARRAYLIST",(Serializable)object);
intent.putExtra("BUNDLE",args);
startActivity(intent);
In the Transfer.class
Intent intent = getIntent();
Bundle args = intent.getBundleExtra("BUNDLE");
ArrayList<Object> object = (ArrayList<Object>) args.getSerializable("ARRAYLIST");
Hope this help's someone.
Using Parcelable to pass data between Activity
This usually works when you have created DataModel
e.g. Suppose we have a json of type
{
"bird": [{
"id": 1,
"name": "Chicken"
}, {
"id": 2,
"name": "Eagle"
}]
}
Here bird is a List and it contains two elements so
we will create the models using jsonschema2pojo
Now we have the model class Name BirdModel and Bird
BirdModel consist of List of Bird
and Bird contains name and id
Go to the bird class and add interface "implements Parcelable"
add implemets method in android studio by Alt+Enter
Note: A dialog box will appear saying Add implements method
press Enter
The add Parcelable implementation by pressing the Alt + Enter
Note: A dialog box will appear saying Add Parcelable implementation
and Enter again
Now to pass it to the intent.
List<Bird> birds = birdModel.getBird();
Intent intent = new Intent(Current.this, Transfer.class);
Bundle bundle = new Bundle();
bundle.putParcelableArrayList("Birds", birds);
intent.putExtras(bundle);
startActivity(intent);
And on Transfer Activity onCreate
List<Bird> challenge = this.getIntent().getExtras().getParcelableArrayList("Birds");
Thanks
If there is any problem please let me know.
Steps:
Implements your object class to serializable
public class Question implements Serializable`
Put this in your Source Activity
ArrayList<Question> mQuestionList = new ArrayList<Question>;
mQuestionsList = QuestionBank.getQuestions();
mQuestionList.add(new Question(ops1, choices1));
Intent intent = new Intent(SourceActivity.this, TargetActivity.class);
intent.putExtra("QuestionListExtra", mQuestionList);
Put this in your Target Activity
ArrayList<Question> questions = new ArrayList<Question>();
questions = (ArrayList<Questions>) getIntent().getSerializableExtra("QuestionListExtra");
It works well,
public class Question implements Serializable {
private int[] operands;
private int[] choices;
private int userAnswerIndex;
public Question(int[] operands, int[] choices) {
this.operands = operands;
this.choices = choices;
this.userAnswerIndex = -1;
}
public int[] getChoices() {
return choices;
}
public void setChoices(int[] choices) {
this.choices = choices;
}
public int[] getOperands() {
return operands;
}
public void setOperands(int[] operands) {
this.operands = operands;
}
public int getUserAnswerIndex() {
return userAnswerIndex;
}
public void setUserAnswerIndex(int userAnswerIndex) {
this.userAnswerIndex = userAnswerIndex;
}
public int getAnswer() {
int answer = 0;
for (int operand : operands) {
answer += operand;
}
return answer;
}
public boolean isCorrect() {
return getAnswer() == choices[this.userAnswerIndex];
}
public boolean hasAnswered() {
return userAnswerIndex != -1;
}
#Override
public String toString() {
StringBuilder builder = new StringBuilder();
// Question
builder.append("Question: ");
for(int operand : operands) {
builder.append(String.format("%d ", operand));
}
builder.append(System.getProperty("line.separator"));
// Choices
int answer = getAnswer();
for (int choice : choices) {
if (choice == answer) {
builder.append(String.format("%d (A) ", choice));
} else {
builder.append(String.format("%d ", choice));
}
}
return builder.toString();
}
}
In your Source Activity, use this :
List<Question> mQuestionList = new ArrayList<Question>;
mQuestionsList = QuestionBank.getQuestions();
mQuestionList.add(new Question(ops1, choices1));
Intent intent = new Intent(SourceActivity.this, TargetActivity.class);
intent.putExtra("QuestionListExtra", ArrayList<Question>mQuestionList);
In your Target Activity, use this :
List<Question> questions = new ArrayList<Question>();
questions = (ArrayList<Question>)getIntent().getSerializableExtra("QuestionListExtra");
Your bean or pojo class should implements parcelable interface.
For example:
public class BeanClass implements Parcelable{
String name;
int age;
String sex;
public BeanClass(String name, int age, String sex) {
this.name = name;
this.age = age;
this.sex = sex;
}
public static final Creator<BeanClass> CREATOR = new Creator<BeanClass>() {
#Override
public BeanClass createFromParcel(Parcel in) {
return new BeanClass(in);
}
#Override
public BeanClass[] newArray(int size) {
return new BeanClass[size];
}
};
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(name);
dest.writeInt(age);
dest.writeString(sex);
}
}
Consider a scenario that you want to send the arraylist of beanclass type from Activity1 to Activity2.
Use the following code
Activity1:
ArrayList<BeanClass> list=new ArrayList<BeanClass>();
private ArrayList<BeanClass> getList() {
for(int i=0;i<5;i++) {
list.add(new BeanClass("xyz", 25, "M"));
}
return list;
}
private void gotoNextActivity() {
Intent intent=new Intent(this,Activity2.class);
/* Bundle args = new Bundle();
args.putSerializable("ARRAYLIST",(Serializable)list);
intent.putExtra("BUNDLE",args);*/
Bundle bundle = new Bundle();
bundle.putParcelableArrayList("StudentDetails", list);
intent.putExtras(bundle);
startActivity(intent);
}
Activity2:
ArrayList<BeanClass> listFromActivity1=new ArrayList<>();
listFromActivity1=this.getIntent().getExtras().getParcelableArrayList("StudentDetails");
if (listFromActivity1 != null) {
Log.d("listis",""+listFromActivity1.toString());
}
I think this basic to understand the concept.
Pass your object via Parcelable.
And here is a good tutorial to get you started.
First Question should implements Parcelable like this and add the those lines:
public class Question implements Parcelable{
public Question(Parcel in) {
// put your data using = in.readString();
this.operands = in.readString();;
this.choices = in.readString();;
this.userAnswerIndex = in.readString();;
}
public Question() {
}
#Override
public int describeContents() {
// TODO Auto-generated method stub
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(operands);
dest.writeString(choices);
dest.writeString(userAnswerIndex);
}
public static final Parcelable.Creator<Question> CREATOR = new Parcelable.Creator<Question>() {
#Override
public Question[] newArray(int size) {
return new Question[size];
}
#Override
public Question createFromParcel(Parcel source) {
return new Question(source);
}
};
}
Then pass your data like this:
Question question = new Question();
// put your data
Intent resultIntent = new Intent(this, ResultActivity.class);
resultIntent.putExtra("QuestionsExtra", question);
startActivity(resultIntent);
And get your data like this:
Question question = new Question();
Bundle extras = getIntent().getExtras();
if(extras != null){
question = extras.getParcelable("QuestionsExtra");
}
This will do!
The easiest way to pass ArrayList using intent
Add this line in dependencies block build.gradle.
implementation 'com.google.code.gson:gson:2.2.4'
pass arraylist
ArrayList<String> listPrivate = new ArrayList<>();
Intent intent = new Intent(MainActivity.this, ListActivity.class);
intent.putExtra("private_list", new Gson().toJson(listPrivate));
startActivity(intent);
retrieve list in another activity
ArrayList<String> listPrivate = new ArrayList<>();
Type type = new TypeToken<List<String>>() {
}.getType();
listPrivate = new Gson().fromJson(getIntent().getStringExtra("private_list"), type);
You can use object also instead of String in type
Works for me..
Simple as that !! worked for me
From activity
Intent intent = new Intent(Viewhirings.this, Informaall.class);
intent.putStringArrayListExtra("list",nselectedfromadapter);
startActivity(intent);
TO activity
Bundle bundle = getIntent().getExtras();
nselectedfromadapter= bundle.getStringArrayList("list");
If your class Question contains only primitives, Serializeble or String fields you can implement him Serializable. ArrayList is implement Serializable, that's why you can put it like Bundle.putSerializable(key, value) and send it to another Activity.
IMHO, Parcelable - it's very long way.
I do one of two things in this scenario
Implement a serialize/deserialize system for my objects and pass them as Strings (in JSON format usually, but you can serialize them any way you'd like)
Implement a container that lives outside of the activities so that all my activities can read and write to this container. You can make this container static or use some kind of dependency injection to retrieve the same instance in each activity.
Parcelable works just fine, but I always found it to be an ugly looking pattern and doesn't really add any value that isn't there if you write your own serialization code outside of the model.
You must need to also implement Parcelable interface and must add writeToParcel method to your Questions class with Parcel argument in Constructor in addition to Serializable. otherwise app will crash.
Your arrayList:
ArrayList<String> yourArray = new ArrayList<>();
Write this code from where you want intent:
Intent newIntent = new Intent(this, NextActivity.class);
newIntent.putExtra("name",yourArray);
startActivity(newIntent);
In Next Activity:
ArrayList<String> myArray = new ArrayList<>();
Write this code in onCreate:
myArray =(ArrayList<String>)getIntent().getSerializableExtra("name");
To set the data in kotlin
val offerIds = ArrayList<Offer>()
offerIds.add(Offer(1))
retrunIntent.putExtra(C.OFFER_IDS, offerIds)
To get the data
val offerIds = data.getSerializableExtra(C.OFFER_IDS) as ArrayList<Offer>?
Now access the arraylist
Implements Parcelable and send arraylist as putParcelableArrayListExtra and get it from next activity getParcelableArrayListExtra
example:
Implement parcelable on your custom class -(Alt +enter) Implement its methods
public class Model implements Parcelable {
private String Id;
public Model() {
}
protected Model(Parcel in) {
Id= in.readString();
}
public static final Creator<Model> CREATOR = new Creator<Model>() {
#Override
public ModelcreateFromParcel(Parcel in) {
return new Model(in);
}
#Override
public Model[] newArray(int size) {
return new Model[size];
}
};
public String getId() {
return Id;
}
public void setId(String Id) {
this.Id = Id;
}
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(Id);
}
}
Pass class object from activity 1
Intent intent = new Intent(Activity1.this, Activity2.class);
intent.putParcelableArrayListExtra("model", modelArrayList);
startActivity(intent);
Get extra from Activity2
if (getIntent().hasExtra("model")) {
Intent intent = getIntent();
cartArrayList = intent.getParcelableArrayListExtra("model");
}
Your intent creation seems correct if your Question implements Parcelable.
In the next activity you can retrieve your list of questions like this:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if(getIntent() != null && getIntent().hasExtra("QuestionsExtra")) {
List<Question> mQuestionsList = getIntent().getParcelableArrayListExtra("QuestionsExtra");
}
}
You can pass the arraylist from one activity to another by using bundle with intent.
Use the code below
This is the shortest and most suitable way to pass arraylist
bundle.putStringArrayList("keyword",arraylist);
I found that most of the answers work but with a warning. So I have a tricky way to achieve this without any warning.
ArrayList<Question> questionList = new ArrayList<>();
...
Intent intent = new Intent(CurrentActivity.this, ToOpenActivity.class);
for (int i = 0; i < questionList.size(); i++) {
Question question = questionList.get(i);
intent.putExtra("question" + i, question);
}
startActivity(intent);
And now in Second Activity
ArrayList<Question> questionList = new ArrayList<>();
Intent intent = getIntent();
int i = 0;
while (intent.hasExtra("question" + i)){
Question model = (Question) intent.getSerializableExtra("question" + i);
questionList.add(model);
i++;
}
Note:
implements Serializable in your Question class.
You can use parcelable for object passing which is more efficient than Serializable .
Kindly refer the link which i am share contains complete parcelable sample.
Click download ParcelableSample.zip
You can Pass Arraylist/Pojo using bundle like this ,
Intent intent = new Intent(MainActivity.this, SecondActivity.class);
Bundle args = new Bundle();
args.putSerializable("imageSliders",(Serializable)allStoriesPojo.getImageSliderPojos());
intent.putExtra("BUNDLE",args);
startActivity(intent);
Get those values in SecondActivity like this
Intent intent = getIntent();
Bundle args = intent.getBundleExtra("BUNDLE");
String filter = bundle.getString("imageSliders");
You can try this. I think it will help you.
Don't fotget to Initialize value into ArrayList
ArrayList<String> imageList = new ArrayList<>();
Send data using intent.putStringArrayListExtra()....
Intent intent = new Intent(this, NextActivity.class);
intent.putStringArrayListExtra("IMAGE_LIST", imageList);
startActivity(intent);
Receive data using intent.getStringArrayListExtra()...
ArrayList<String> imageList = new ArrayList<>();
Intent intent = getIntent();
imageList = intent.getStringArrayListExtra("IMAGE_LIST");
As we know getSerializable() is deprecated so we can use other easy way to transfer array between activities or between fragment to activities:
First initialize Array of Cars:
private var carsList = ArrayList<Cars>()
On sending Activity/Fragment side:
val intent = Intent(mContext, SearchActivity::class.java)
intent.putExtra("cars_list", Gson().toJson(carsList))
startActivity(intent)
On Receiving Activity:
val type: Type = object : TypeToken<List<CarsModel?>?>() {}.type
categoryList = Gson().fromJson(intent.getStringExtra("cars_list"), type)
I had the exact same question and while still hassling with the Parcelable, I found out that the static variables are not such a bad idea for the task.
You can simply create a
public static ArrayList<Parliament> myObjects = ..
and use it from elsewhere via MyRefActivity.myObjects
I was not sure about what public static variables imply in the context of an application with activities. If you also have doubts about either this or on performance aspects of this approach, refer to:
What's the best way to share data between activities?
Using static variables in Android
Cheers.

Passing vector of Class<?> objects to other activity - in Android

I'd like to ask what I'm doing wrong if I want to pass such data to other class:
String [] codes = {"code"};
Class<?> [] classes = { TestActivity.class };
Intent i = new Intent();
Pack p = new Pack();
p.eat(classes,codes);
i.putExtra("com.mbar", p);
i.setClass(this, CaptureActivity.class);
startActivity(i);
}
}
Later in other activity I try it to unpack like that:
Bundle b = getIntent().getExtras();
Pack p = (Pack)b.getParcelable("com.mbar");
if(p!=null){
classes = p.getClasses();
codes = p.getNames();
The Pack class which is Parcelable looks like:
package com.mbar;
import android.os.Parcel;
import android.os.Parcelable;
public class Pack implements Parcelable {
Class<?>[] classes;
String [] codes;
public void eat(Class<?>[] classes,String [] codes){
this.classes = classes;
this.codes = codes;
}
public Class<?>[] getClasses(){
return this.classes;
}
public String [] getNames(){
return this.codes;
}
#Override
public int describeContents() {
// TODO Auto-generated method stub
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
}
}
String [] codes = {"code"};
Class<?> [] classes = { TestActivity.class };
Intent i = new Intent();
Pack p = new Pack(classes,codes);
i.putExtra("com.mbar", p);
i.setClass(this, CaptureActivity.class);
startActivity(i)
Pack p = (Pack)getIntent().getParcelableExtra("com.mbar");
if(p!=null){
classes = p.getClasses();
codes = p.getNames();
public static class Pack implements Parcelable {
Class<?>[] classes;
String[] codes;
public Pack(Class<?>[] classes, String[] codes) {
this.classes = classes;
this.codes = codes;
}
public Pack(Parcel in) {
int len = in.readInt();
String[] classnames = new String[len];
in.readStringArray(classnames);
classes = new Class<?>[classnames.length];
for (int i = 0; i < classnames.length; i++) {
try {
classes[i] = Class.forName(classnames[i]);
} catch (ClassNotFoundException e) {
}
}
len = in.readInt();
codes = new String[len];
in.readStringArray(codes);
}
public Class<?>[] getClasses() {
return this.classes;
}
public String[] getNames() {
return this.codes;
}
#Override
public int describeContents() {
return 0;
}
public static final Parcelable.Creator<Pack> CREATOR = new Parcelable.Creator<Pack>() {
public Pack createFromParcel(Parcel in) {
return new Pack(in);
}
public Pack[] newArray(int size) {
return new Pack[size];
}
};
#Override
public void writeToParcel(Parcel dest, int flags) {
String[] classnames = new String[classes.length];
for (int i = 0; i < classes.length; i++) {
classnames[i] = classes[i].getName();
}
dest.writeInt(classnames.length);
dest.writeStringArray(classnames);
dest.writeInt(codes.length);
dest.writeStringArray(codes);
}
}

Categories

Resources