In my activity, I'm calling a second activity from the main activity by startActivityForResult. In my second activity, there are some methods that finish this activity (maybe without a result), however, just one of them returns a result.
For example, from the main activity, I call a second one. In this activity, I'm checking some features of a handset, such as does it have a camera. If it doesn't have then I'll close this activity. Also, during the preparation of MediaRecorder or MediaPlayer if a problem happens then I'll close this activity.
If its device has a camera and recording is done completely, then after recording a video if a user clicks on the done button then I'll send the result (address of the recorded video) back to the main activity.
How do I check the result from the main activity?
From your FirstActivity, call the SecondActivity using the startActivityForResult() method.
For example:
int LAUNCH_SECOND_ACTIVITY = 1
Intent i = new Intent(this, SecondActivity.class);
startActivityForResult(i, LAUNCH_SECOND_ACTIVITY);
In your SecondActivity, set the data which you want to return back to FirstActivity. If you don't want to return back, don't set any.
For example: In SecondActivity if you want to send back data:
Intent returnIntent = new Intent();
returnIntent.putExtra("result",result);
setResult(Activity.RESULT_OK,returnIntent);
finish();
If you don't want to return data:
Intent returnIntent = new Intent();
setResult(Activity.RESULT_CANCELED, returnIntent);
finish();
Now in your FirstActivity class, write the following code for the onActivityResult() method.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == LAUNCH_SECOND_ACTIVITY) {
if(resultCode == Activity.RESULT_OK){
String result=data.getStringExtra("result");
}
if (resultCode == Activity.RESULT_CANCELED) {
// Write your code if there's no result
}
}
} //onActivityResult
To implement passing data between two activities in a much better way in Kotlin, please go through 'A better way to pass data between Activities'.
How to check the result from the main activity?
You need to override Activity.onActivityResult() and then check its parameters:
requestCode identifies which app returned these results. This is defined by you when you call startActivityForResult().
resultCode informs you whether this app succeeded, failed, or something different
data holds any information returned by this app. This may be null.
Example
To see the entire process in context, here is a supplemental answer. See my fuller answer for more explanation.
MainActivity.java
public class MainActivity extends AppCompatActivity {
// Add a different request code for every activity you are starting from here
private static final int SECOND_ACTIVITY_REQUEST_CODE = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
// "Go to Second Activity" button click
public void onButtonClick(View view) {
// Start the SecondActivity
Intent intent = new Intent(this, SecondActivity.class);
startActivityForResult(intent, SECOND_ACTIVITY_REQUEST_CODE);
}
// This method is called when the second activity finishes
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// check that it is the SecondActivity with an OK result
if (requestCode == SECOND_ACTIVITY_REQUEST_CODE) {
if (resultCode == RESULT_OK) { // Activity.RESULT_OK
// get String data from Intent
String returnString = data.getStringExtra("keyName");
// set text view with string
TextView textView = (TextView) findViewById(R.id.textView);
textView.setText(returnString);
}
}
}
}
SecondActivity.java
public class SecondActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
}
// "Send text back" button click
public void onButtonClick(View view) {
// get the text from the EditText
EditText editText = (EditText) findViewById(R.id.editText);
String stringToPassBack = editText.getText().toString();
// put the String to pass back into an Intent and close this activity
Intent intent = new Intent();
intent.putExtra("keyName", stringToPassBack);
setResult(RESULT_OK, intent);
finish();
}
}
Complementing the answer from Nishant, the best way to return the activity result is:
Intent returnIntent = getIntent();
returnIntent.putExtra("result",result);
setResult(RESULT_OK,returnIntent);
finish();
I was having a problem with
new Intent();
Then I found out that the correct way is using
getIntent();
to get the current intent.
startActivityForResult: Deprecated in Android X
For the new way we have registerForActivityResult.
In Java :
// You need to create a launcher variable inside onAttach or onCreate or global, i.e, before the activity is displayed
ActivityResultLauncher<Intent> launchSomeActivity = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
#Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
Intent data = result.getData();
// your operation....
}
}
});
public void openYourActivity() {
Intent intent = new Intent(this, SomeActivity.class);
launchSomeActivity.launch(intent);
}
In Kotlin :
var resultLauncher = registerForActivityResult(StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
val data: Intent? = result.data
// your operation...
}
}
fun openYourActivity() {
val intent = Intent(this, SomeActivity::class.java)
resultLauncher.launch(intent)
}
Advantage:
The new way is reduce complexity which we faced when we call the activity from a fragment or from another activity
Easily ask for any permission and get callback
For those who have problem with wrong requestCode in onActivityResult
If you are calling startActivityForResult() from your Fragment, the requestCode is changed by the Activity that owns the Fragment.
If you want to get the correct resultCode in your activity try this:
Change:
startActivityForResult(intent, 1); To:
getActivity().startActivityForResult(intent, 1);
The ActivityResultRegistry is the recommended approach
ComponentActivity now provides an ActivityResultRegistry that lets you handle the startActivityForResult()+onActivityResult() as well as requestPermissions()+onRequestPermissionsResult() flows without overriding methods in your Activity or Fragment, brings increased type safety via ActivityResultContract, and provides hooks for testing these flows.
It is strongly recommended to use the Activity Result APIs introduced in Android 10 Activity 1.2.0-alpha02 and Fragment 1.3.0-alpha02.
Add this to your build.gradle
def activity_version = "1.2.0-beta01"
// Java language implementation
implementation "androidx.activity:activity:$activity_version"
// Kotlin
implementation "androidx.activity:activity-ktx:$activity_version"
How to use the pre-built contract
This new API has the following pre-built functionalities
TakeVideo
PickContact
GetContent
GetContents
OpenDocument
OpenDocuments
OpenDocumentTree
CreateDocument
Dial
TakePicture
RequestPermission
RequestPermissions
An example that uses the takePicture contract:
private val takePicture = prepareCall(ActivityResultContracts.TakePicture()) { bitmap: Bitmap? ->
// Do something with the Bitmap, if present
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
button.setOnClickListener { takePicture() }
}
So what’s going on here? Let’s break it down slightly. takePicture is just a callback which returns a nullable Bitmap - whether or not it’s null depends on whether or not the onActivityResult process was successful. prepareCall then registers this call into a new feature on ComponentActivity called the ActivityResultRegistry - we’ll come back to this later. ActivityResultContracts.TakePicture() is one of the built-in helpers which Google have created for us, and finally invoking takePicture actually triggers the Intent in the same way that you would previously with Activity.startActivityForResult(intent, REQUEST_CODE).
How to write a custom contract
A simple contract that takes an Int as an input and returns a string that the requested Activity returns in the result Intent.
class MyContract : ActivityResultContract<Int, String>() {
companion object {
const val ACTION = "com.myapp.action.MY_ACTION"
const val INPUT_INT = "input_int"
const val OUTPUT_STRING = "output_string"
}
override fun createIntent(input: Int): Intent {
return Intent(ACTION)
.apply { putExtra(INPUT_INT, input) }
}
override fun parseResult(resultCode: Int, intent: Intent?): String? {
return when (resultCode) {
Activity.RESULT_OK -> intent?.getStringExtra(OUTPUT_STRING)
else -> null
}
}
}
class MyActivity : AppCompatActivity() {
private val myActionCall = prepareCall(MyContract()) { result ->
Log.i("MyActivity", "Obtained result: $result")
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
...
button.setOnClickListener {
myActionCall(500)
}
}
}
Check this official documentation for more information.
If you want to update the user interface with the activity result, you can't to use this.runOnUiThread(new Runnable() {}. Doing this, the UI won't refresh with the new value. Instead, you can do this:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
return;
}
global_lat = data.getDoubleExtra("LATITUDE", 0);
global_lng = data.getDoubleExtra("LONGITUDE", 0);
new_latlng = true;
}
#Override
protected void onResume() {
super.onResume();
if(new_latlng)
{
PhysicalTagProperties.this.setLocation(global_lat, global_lng);
new_latlng=false;
}
}
This seems silly, but it works pretty well.
In Kotlin
Suppose A & B are activities the navigation is from A -> B
We need the result back from A <- B
in A
// calling the Activity B
resultLauncher.launch(Intent(requireContext(), B::class.java))
// we get data in here from B
private var resultLauncher =
registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
when (result.resultCode) {
Activity.RESULT_OK -> {
result.data?.getStringExtra("VALUE")?.let {
// data received here
}
}
Activity.RESULT_CANCELED -> {
// cancel or failure
}
}
}
In B
// Sending result value back to A
if (success) {
setResult(RESULT_OK, Intent().putExtra("VALUE", value))
} else {
setResult(RESULT_CANCELED)
}
It is a very common problem on Android
It can be broken down into three pieces
Start Activity B (happens in Activity A)
Set requested data (happens in activity B)
Receive requested data (happens in activity A)
startActivity B
Intent i = new Intent(A.this, B.class);
startActivity(i);
Set requested data
In this part, you decide whether you want to send data back or not when a particular event occurs.
E.g.: In activity B there is an EditText and two buttons b1, b2.
Clicking on Button b1 sends data back to activity A.
Clicking on Button b2 does not send any data.
Sending data
b1......clickListener
{
Intent resultIntent = new Intent();
resultIntent.putExtra("Your_key", "Your_value");
setResult(RES_CODE_A, resultIntent);
finish();
}
Not sending data
b2......clickListener
{
setResult(RES_CODE_B, new Intent());
finish();
}
The user clicks the back button
By default, the result is set with Activity.RESULT_CANCEL response code
Retrieve result
For that override onActivityResult method
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RES_CODE_A) {
// b1 was clicked
String x = data.getStringExtra("RES_CODE_A");
}
else if(resultCode == RES_CODE_B){
// b2 was clicked
}
else{
// The back button was clicked
}
}
I will post the new "way" with Android X in a short answer (because in some case you does not need custom registry or contract). If you want more information, see: Getting a result from an activity
Important: there is actually a bug with the backward compatibility of Android X so you have to add fragment_version in your Gradle file. Otherwise you will get an exception "New result API error : Can only use lower 16 bits for requestCode".
dependencies {
def activity_version = "1.2.0-beta01"
// Java language implementation
implementation "androidx.activity:activity:$activity_version"
// Kotlin
implementation "androidx.activity:activity-ktx:$activity_version"
def fragment_version = "1.3.0-beta02"
// Java language implementation
implementation "androidx.fragment:fragment:$fragment_version"
// Kotlin
implementation "androidx.fragment:fragment-ktx:$fragment_version"
// Testing Fragments in Isolation
debugImplementation "androidx.fragment:fragment-testing:$fragment_version"
}
Now you just have to add this member variable of your activity. This use a predefined registry and generic contract.
public class MyActivity extends AppCompatActivity{
...
/**
* Activity callback API.
*/
// https://developer.android.com/training/basics/intents/result
private ActivityResultLauncher<Intent> mStartForResult = registerForActivityResult(new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
#Override
public void onActivityResult(ActivityResult result) {
switch (result.getResultCode()) {
case Activity.RESULT_OK:
Intent intent = result.getData();
// Handle the Intent
Toast.makeText(MyActivity.this, "Activity returned ok", Toast.LENGTH_SHORT).show();
break;
case Activity.RESULT_CANCELED:
Toast.makeText(MyActivity.this, "Activity canceled", Toast.LENGTH_SHORT).show();
break;
}
}
});
Before new API you had :
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MyActivity .this, EditActivity.class);
startActivityForResult(intent, Constants.INTENT_EDIT_REQUEST_CODE);
}
});
You may notice that the request code is now generated (and hold) by the Google framework.
Your code becomes:
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MyActivity .this, EditActivity.class);
mStartForResult.launch(intent);
}
});
First you use startActivityForResult() with parameters in the first Activity and if you want to send data from the second Activity to first Activity then pass the value using Intent with the setResult() method and get that data inside the onActivityResult() method in the first Activity.
In your Main Activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
findViewById(R.id.takeCam).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent=new Intent(getApplicationContext(),TakePhotoActivity.class);
intent.putExtra("Mode","Take");
startActivity(intent);
}
});
findViewById(R.id.selectGal).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent=new Intent(getApplicationContext(),TakePhotoActivity.class);
intent.putExtra("Mode","Gallery");
startActivity(intent);
}
});
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
}
In Second Activity to Display
private static final int CAMERA_REQUEST = 1888;
private ImageView imageView;
private static final int MY_CAMERA_PERMISSION_CODE = 100;
private static final int PICK_PHOTO_FOR_AVATAR = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_take_photo);
imageView=findViewById(R.id.imageView);
if(getIntent().getStringExtra("Mode").equals("Gallery"))
{
pickImage();
}
else {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.CAMERA}, MY_CAMERA_PERMISSION_CODE);
} else {
Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_REQUEST);
}
}
}
}
public void pickImage() {
Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
startActivityForResult(intent, PICK_PHOTO_FOR_AVATAR);
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults)
{
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == MY_CAMERA_PERMISSION_CODE)
{
if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
{
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_REQUEST);
}
else
{
Toast.makeText(this, "Camera Permission Denied..", Toast.LENGTH_LONG).show();
}
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == CAMERA_REQUEST && resultCode == Activity.RESULT_OK) {
Bitmap photo = (Bitmap) data.getExtras().get("data");
imageView.setImageBitmap(photo);
}
if (requestCode == PICK_PHOTO_FOR_AVATAR && resultCode == Activity.RESULT_OK) {
if (data == null) {
Log.d("ABC","No Such Image Selected");
return;
}
try {
Uri selectedData=data.getData();
Log.d("ABC","Image Pick-Up");
imageView.setImageURI(selectedData);
InputStream inputStream = getApplicationContext().getContentResolver().openInputStream(selectedData);
Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
Bitmap bmp=MediaStore.Images.Media.getBitmap(getContentResolver(),selectedData);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch(IOException e){
}
}
}
You need to override Activity.onActivityResult():
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CODE_ONE) {
String a = data.getStringExtra("RESULT_CODE_ONE");
}
else if(resultCode == RESULT_CODE_TWO){
// b was clicked
}
else{
}
}
Greetings fellow programmers,
I have been having some issues with understanding why my child's intent doesn't return the proper value to my parent's intent properly.
private static final int REQUEST_CODE_CHEAT = 0;
Now here is how I call my explicit intent
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
boolean isTrue = mStatements[mStatementIndex].isAnswerTrue();
Intent intent = SubActivity.newIntent(MainActivity.this, isTrue);
startActivityForResult(intent, REQUEST_CODE_CHEAT);
}
});
This is the code for the SubActivity that creates the interfacing Intent
public static Intent newIntent(Context packageContext, boolean answerIsTrue){
Intent intent = new Intent(packageContext, SubActivity.class);
intent.putExtra(EXTRA_ANSWER_SHOWN, answerIsTrue);
return intent;
}
Also, have the following keys to keep track of what goes where
private static final String EXTRA_ANSWER_IS_TRUE = "com.tsourtzis.android.test.answer_is_true";
private static final String EXTRA_ANSWER_SHOWN = "com.tsourtzis.android.test.answer_shown";
Finally some methods to be certain what values are passed
private void setAnswerShownResult(boolean isAnswerShown){
Intent data = new Intent();
data.putExtra(EXTRA_ANSWER_IS_TRUE, isAnswerShown);
setResult(RESULT_OK, data);
}
Here I'm sending back the intent to the MainActivity with setResult();
public static boolean wasAnswerShown(Intent result){
return result.getBooleanExtra(EXTRA_ANSWER_SHOWN, false);
}
Moreover, I have this method here to evaluate the result, but checking first if the user has created it.
public void evaluateStatement(boolean userChoice){
boolean statementValue = mStatements[mStatementIndex].isAnswerTrue();
int textResId = 0;
if(mBoolResult){
textResId = R.string.judgment_toast;
}else{
if(userChoice == statementValue){
textResId = R.string.correct_toast;
}else{
textResId = R.string.incorrect_toast;
}
}
Toast.makeText(this, textResId, Toast.LENGTH_SHORT).show();
}
Notice, I have stated the following my MainActivity after using setResult(...) and a field value for keeping the boolean result from the Sub activity.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
if(resultCode != Activity.RESULT_OK){
return;
}
if(requestCode == REQUEST_CODE_CHEAT){
if(data == null){
return;
}
mBoolResult = SubActivity.wasAnswerShown(data);
}
}
Finally just to be clear, here is the field that I have in MainActivity.
private boolean mBoolResult;
I'm not looking for any code answer, I just want to understand why it doesn't work. Thank you!
Do you finish() your SubActivity ?
Seeing that the Toast should be shown any time the method evaluateStatement is called, I guess onActivityResult doesn't dispatch the call to it.
Can you explicit where is the onActivityResult you show last? It's unclear since it's calling CheatActivity#wasAnswerShown() as if it is not in CheatActivity (MainActivity?)
So I have 3 activities: MainActivity, AddEntryActivity, and CategoryActivity. I want to use startActivityForResult from Main -> AddEntry, and then AddEntry -> Category and have the data from Category passed back to AddEntry where it's used as a field in the Entry object result I'm sending back to Main. The problem is, when I call finish() in AddEntryActivity (after returning from CategoryActivity), CategoryActivity opens again. I think it may be a problem with the intents/contexts but I'm new to android dev so I can't figure out what the problem is. Any help would be appreciated!
I am currently calling startActivityForResult() from MainActivity (on button press) to get to AddEntry.
case R.id.addEntryButton:
Intent in = new Intent(this, AddEntryActivity.class);
startActivityForResult(in, 111);
break;
Then from AddEntryActivity, I call another startActivityForResult to get to CategoryActivity (on button press again).
case R.id.chooseCategory:
Intent catAct = new Intent(this, CategoryActivity.class);
startActivityForResult(catAct, 222);
break;
From CategoryActivity, the user can choose a category and it's sent back to AddEntryActivity (I've checked that this works).
In CategoryActivity:
#Override
public void onListItemClick(ListView l, View v, int position, long id) {
Intent i = getIntent();
String category = (String) getListAdapter().getItem(position);
i.putExtra("Category", category);
setResult(RESULT_OK, i);
finish();
}
In AddEntryActivity:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 222 && resultCode == RESULT_OK) {
String cat = data.getStringExtra("Category");
category.setText(cat);
categoryString = cat;
}
}
Then, in AddEntryActivity, when the confirm button is pressed I want to return to MainActivity with a new Entry object containing the category field that was returned from CategoryActivity. So I have this:
case R.id.confirmEntryButton:
Entry entry = new Entry(descString, amountString, date.getText().toString(), categoryString);
Intent main = new Intent(this, MainActivity.class);
main.putExtra("newEntry", entry);
setResult(RESULT_OK, main);
finish();
The problem is, when the confirm button is pressed, the CategoryActivity screen pops up again. The weird thing is, the onActivityResult method in MainActivity (below) actually runs as when you close the CategoryActivity screen via the back button, you can see that the entry object has been added so I can't seem to figure out what's causing the category screen to pop up.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 111 && resultCode == RESULT_OK) {
Entry entry = data.getParcelableExtra("newEntry");
entries.add(entry);
entryListView.setAdapter(eAdapter);
}
}
Check your switch case statement to make sure it isn't missing a break and falling through to the next part.
This is the function which is used to send data to the Main activity.
public void sendData(){
String name = Bookname.getText().toString();
String number = Integer.parseInt(Bookpage.getText().toString());
String description = Booknote.getText().toString();
Intent back = new Intent(getApplicationContext(),MainActivity.class);
back.putExtra("Bookname",name);
back.putExtra("Booknote",description);
back.putExtra("number",number);
setResult(RESULT_OK, back);
finish();
}
This is where I used the function.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if(item.getItemId() == R.id.Color_picker){
Toast.makeText(this, "ColoRS", Toast.LENGTH_SHORT).show();
}
if(item.getItemId() == R.id.Check_icon){
sendData();
}
return true;
}
}
This is how I get the strings in the Main Activity
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1 && resultCode == RESULT_OK) {
Ref c1 = new Ref(data.getStringExtra("Bookname"), data.getStringExtra("Booknote"),data.getIntExtra("number",0),data.getIntExtra("color", Color.RED));
adapter.add(c1);
}
}
My problem is that the data are only written once and when the function should be sending different data it sends the same data as the first entered data.
If you send your activityOnResult with 1 as REQUEST_CODE is OK
The only problem I guess you are having (I do not have much more information) is since I see and adapter, I guess you should call adapter.notifyDataSetChanged() to see changes on your "list"?
Also you can "clear" the intent, to avoid duplicated stuff, every time you go to onActivityResult() you can do this getIntent().removeExtra("key"); to ensure, next time will come different data.
If you do this, you have to do the other logic good to work with this...
my app always crashes when i send an object to the main activity. I want it so the main activity displays a String from my class but everytime I press the row in the second activity and go back to the main activity the app crashes can someone please help me to fix this, thanks.
my class below
public class Ship implements Serializable {
public String test()
{
String s = "Hello Android!";
return s;
}
}
Second Activity
hangarList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
Intent sendListEvents = new Intent();
if(position == 1)
{
Ship test = new Ship();
sendListEvents.putExtra("ship1", test);
}
//insert position events ^^^
setResult(RESULT_OK, sendListEvents);
}
});
Main Activity below
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == result) {
if (resultCode == RESULT_OK) {
Intent getData = getIntent();
Ship ship1 = (Ship) getData.getSerializableExtra("ship1");
String s = ship1.test();
test.setText(s);
}
}
}
Try replacing this:
Intent getData = getIntent();
Ship ship1 = (Ship) getData.getSerializableExtra("Ship1");
With this:
Ship ship1 = (Ship) data.getSerializableExtra("ship1");
Also, I recommend making "ship1" a final static constant value to avoid typos when trying to reference it. If you need to know the position in the list that was clicked, you can pass that as another intent extra.