So for one of my personal projects I want to pass an arraylist of ZipEntry objects from one activity to another but I am unable to do so. I have tried the following things:
Creating Bundle() and passing that bundle using putExtra()
Passing ArrayList directly using putExta()
Creating bundle & passing it using putExtra():
Implementation:
// Add data to intent and launch install activity
val newActIntent = Intent(this, InstallActivity::class.java)
val data = Bundle()
data.putSerializable("x", languageListAdapter.selectedItems)
newActIntent.putExtra("z", data)
this.startActivity(newActIntent)
Error:
java.lang.IllegalArgumentException: Parcel: unknown type for value split_config.en.apk
Passing ArrayList<> directly using putExtra()
Implementation:
val newActIntent = Intent(this, InstallActivity::class.java)
newActIntent.putExtra("x", languageListAdapter.selectedItems)
this.startActivity(newActIntent)
Error:
java.lang.IllegalArgumentException: Parcel: unknown type for value split_config.en.apk
Note: ZipEntry object is java.util.zip.ZipEntry
In order to send an ArrayList<ZipEntry> from one Activity to another you need to make sure that your ZipEntry object is serializable, you can do it by implementing Serializable interface.
You can also use Parcelable as an alternative of Serializable.
If you use Serializable you use getSerializableExtra and if it's Parcelable you use getParcelableArrayListExtra
#Parcelize
data class ZipEntry : Parcelable
Fixed this issue thanks to the comment from #wambada
Implementation:
Created a singleton object to store the ArrayLists
object ZipEntrySingleton {
var aList: ArrayList<ZipEntry>? = null
var lList: ArrayList<ZipEntry>? = null
}
Created the singleton object in activity 1 and passed the data to it.
// Add data to intent and launch install activity
val newActIntent = Intent(this, InstallActivity::class.java)
val x = ZipEntrySingleton
x.aList = xListAdapter.selectedItems
x.lList = yListAdapter.selectedItems
this.startActivity(newActIntent)
Retrieved the data in the new activity by using:
ZipEntrySingleton.aList
Related
I have 2 activities. And I need pass a lot of variables from one activity to another activity:
val intent = Intent(this, SecondActivity::class.java)
intent.putExtra(ACCOUNT1, accoun1)
intent.putExtra(ACCOUNT2, accoun2)
intent.putExtra(ACCOUNT3, accoun3)
intent.putExtra(ACCOUNT4, accoun4)
intent.putExtra(ACCOUNT5, accoun5)
intent.putExtra(ACCOUNT6, accoun6)
intent.putExtra(ACCOUNT7, accoun7)
intent.putExtra(ACCOUNT8, accoun8)
intent.putExtra(ACCOUNT9, accoun9)
and so on. How can I make this transfer easier? Maybe is some other ways to pass multiply values from one activity to another activity?
I recently had a similar case.
How I solved:
I created an entity that kept all the information for me, that way, I just passed an object between activities, but I had everything I needed inside that object.
Hope this can help.
There is a bundleOf function in the Jetpack core-ktx library that works like mapOf.
val intent = Intent(this, SecondActivity::class.java)
val extras = bundleOf(
ACCOUNT1 to accoun1,
ACCOUNT2 to accoun2,
ACCOUNT3 to accoun3,
// etc.
)
intent.putExtras(extras)
But that doesn't save much code compared to just using apply unless you use the same bundle of extras in multiple places in your code:
val intent = Intent(this, SecondActivity::class.java).apply {
putExtra(ACCOUNT1, accoun1)
putExtra(ACCOUNT2, accoun2)
putExtra(ACCOUNT3, accoun3)
//...
}
You could make a parcelable data class that stores all your values and pass that instead. See instructions here for creating the class easily: https://developer.android.com/kotlin/parcelize
#Parcelize
data class AccountInfo(
val account1: String,
val account2: String,
val account3: String,
//...
): Parcelable
Then you can put this into your bundles, and you don't have to create a bunch of the same kinds of variables in both activities, because all the variables are inside one class.
val intent = Intent(this, SecondActivity::class.java).apply {
putExtra(ACCOUNT_INFO, myAccountInfoInstance)
}
if all of your variables has the same type you can add all to list and pass the list to second activity/fragment.
I followed this guide (How to run a certain activity in Android Studio?) to launch another activity aside from my main.
I have a GetUser.xml and ShowUser.xml layouts.
In GetUser.xml, user can enter their name and age.
I have a user class with constructor that takes in name and age inside GetUser.kt. I initialize User object with the values : name, age I got from the input fields in GetUser.
Now when I run the other activity ShowUser, I wish to access this object so I can get the values and display it in ShowUser.xml
My question is how do I access this object from the GetUser.kt and use it in ShowUser.kt ?
As far as I understand, you are looking for extra.
When starting one Activity from another, you can pass data via extra.
Let's say you have a class Person with String name and int age.
There are 2 simple ways to to this.
1. Send data separately
Because Person is a simple class that consists of 2 member fields, we can pass each data separately and combine into Person in started Activity.
We need Intent to do this.
val p = Person(name, age) // Person data
val intent = Intent(this, NewActivity::class.java)
intent.putExtra('name', p.name)
intent.putExtra('age', p.age)
startActivity(intent)
On started NewActivity's onCreate(), you can receive this data and make an object out of it.
val name = intent.getStringExtra('name')
val age = intent.getIntExtra('age')
val combinedPersonData = Person(name, age)
2. Send whole instance
If the class you are trying to send is too big to use method 1, you can try sending it as itself.
To do this, you need to implement Serializable or Parcelable to your class.
class Person(val name: String, val age: Int): Serializable { ... }
Make sure all of the members in the class are also Serializable or are primitive types.
With this, you can send the person object as serializable object.
val p = Person(name, age) // Person data
val intent = Intent(this, NewActivity::class.java)
intent.putExtra('person', p)
startActivity(intent)
In the receiver's onCreate(),
val p = intent.getSerializableExtra('person') as Person
will receive the while Person data.
I'm trying to pass data from activity A to activity B through intent in Kotlin.
The problem is I have a videos: MutableList<Video> and the intent.putParcelableArrayListExtra("VIDEOS", videos) only accepts ArrayList<out Parcelable> as arguments.
Questions
*. How do I send a mutableList data from activity A to activity B?
*. Or Do I have to convert it to ArrayList<Video> ?
PS: Videoimplements Parcelable
Converting it to an ArrayList (or storing it as one in the first place?) is the easy solution if you want to stick to passing it through an Intent. There's an ArrayList constructor that takes a collection as its parameter:
intent.putParcelableArrayListExtra("VIDEOS", ArrayList(videos))
For those asking how the Parcelable class is created, this is the solution I came up with in Kotlin
The Parcelable Class:
#Parcelize
data class ExampleModel(
var stringOne: String,
var stringTwo: String): Parcelable
Then in Activity A you can create an ArrayList and send it via intent to Activity B
private var exampleMutableList: MutableList<ExampleModel> = arrayListOf()
exampleMutableList.add(ExampleModel("hello", "world"))
intent.putExtra("example", ArrayList(exampleMutableList))
And in Activity B we can receive our ArrayList:
exampleMutableList = intent.getParcelableArrayListExtra<ExampleModel>("example") as ArrayList<ExampleModel>
All the best!
This is on the android platform, i have a list of objects of type (FitItem), and i want pass the list from my activity A to another activity B, and on the activity B i want get the list of objects again
Intent yourIntent = new Intent(activityA.this, activityB.class);
Bundle yourBundle = new Bundle();
yourBundle.putString("name", value);
yourIntent.putExtras(yourBundle);
startActivity(yourIntent);
And you get the value in the next Activity (in your onCreate()):
Bundle yourBundle = getIntent().getExtras();
String s = yourBundle.getString("name");
This example is passing a String, but you should be able to grasp how to use it for other objects.
For custom classes:
You will have to have your FitItem class implements Parcelable.
Then in Activity A, from an Intent object, use putParcelableArrayListExtra to pass the list of FitItem to Activity B and in your Activity B, use getParcelableArrayListExtra to retrieve the list of FitItem
If you want to pass list of String, Integer, Float ..., refer to bschultz post
You must serialize your object.
"Seriawhat?"
Ok, first things first: What is object serialization?
"Got it, but how do I do that?"
You can use Parcelable (more code, but faster) or Serializable (less code, but slower). Parcelable vs Serializable.
"Save me some time, show me the code!"
Ok, if you'll use Parcelable, see this.
And if you'll use Serializable, see this and/or this.
Hope that helps!
If they're if the object is serializable, just add them as extras to the intent. I think something like this:
// in Activity A, when starting Activity B
Intent i = new Intent(this, ActivityB.class);
i.putExra("fitItemList", fitItemList);
startActivity(i);
// in Activity B (onCreate)
ArrayList<FitItem> fitItemList = savedInstanceState.getSerializableExtra("fitItemList");
edit:
Just like bschultz already posted :)
Implements Serializable in model class. Then you can pass model class using bundle/intent.
I have two activities, NewTransferMyOwn.java and FromAccount.java
When I go from NewTransferMyOwn.java to FromAccount.java, I do write code as following
Intent i = new Intent(NewTransferMyOwn.this, FromAccount.class);
startActivityForResult(i, FROM_ACCOUNT);
When I do come back from FromAccount.java to NewTransferMyOwn.java, then I want to pass a complete object of class Statement
I do write code as
Statement st = ItemArray.get(arg2);//ItemArray is ArrayList<Statement>, arg2 is int
Intent intent = new Intent(FromAccount.this,NewTransferMyOwn.class).putExtra("myCustomerObj",st);
I do get error as following on putExtra,
Change to 'getIntExtra'
as I do, there is again casting st to int, what is issue over here, how can I pass Statement object towards back to acitivity?
You can also implement your custom class by Serializable and pass the custom Object,
public class MyCustomClass implements Serializable
{
// getter and setters
}
And then pass the Custom Object with the Intent.
intent.putExtra("myobj",customObj);
To retrieve your Object
Custom custom = (Custom) data.getSerializableExtra("myobj");
UPDATE:
To pass your custom Object to the previous Activity while you are using startActivityForResult
Intent data = new Intent();
Custom value = new Custom();
value.setName("StackOverflow");
data.putExtra("myobj", value);
setResult(Activity.RESULT_OK, data);
finish();
To retrieve the custom Object on the Previous Activity
if(requestCode == MyRequestCode){
if(resultCode == Activity.RESULT_OK){
Custom custom = (Custom) data.getSerializableExtra("myobj");
Log.d("My data", custom.getName()) ;
finish();
}
}
You can't pass arbitrary objects between activities. The only data you can pass as extras/in a bundle are either fundamental types or Parcelable objects.
And Parcelables are basically objects that can be serialized/deserialized to/from a string.
You can also consider passing only the URI refering to the content and re-fetching it in the other activity.