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{
}
}
Related
This question already has answers here:
Java solution for "startActivityForResult(Intent,int) in Fragment has been deprecated" when opening external URL?
(2 answers)
Closed last month.
'startActivityForResult(android.content.Intent, int)' is deprecated, what can I do? This is the code for my QR code scanner Android app (Java):
package com.example.wfr;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
private static final int REQUEST_CODE = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.qr_scanner_layout);
//Button click event to open QR scanner
findViewById(R.id.camera_button).setOnClickListener(v -> {
Intent intent = new Intent(MainActivity.this, QRCodeScanner.class);
intent.putExtra("SCAN_FORMATS", "QR_CODE");
startActivityForResult(intent, REQUEST_CODE);
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, #Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_CODE && resultCode == RESULT_OK) {
if (data != null) {
String scannedText = data.getStringExtra("com.journeyapps.barcodescanner.CaptureActivity.SCAN_RESULT");
TextView scannedTextView = findViewById(R.id.scanned_text);
scannedTextView.setText(scannedText);
}
}
}
}
A basic training is available at https://developer.android.com/training/basics/intents/result
Here is an example on how to convert the existing code with the new one:
The old way:
public void openSomeActivityForResult() {
Intent intent = new Intent(this, SomeActivity.class);
startActivityForResult(intent, 123);
}
#Override
protected void onActivityResult (int requestCode, int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK && requestCode == 123) {
doSomeOperations();
}
}
The new way (Java):
public void openSomeActivityForResult() {
Intent intent = new Intent(this, SomeActivity.class);
someActivityResultLauncher.launch(intent);
}
// You can do the assignment inside onAttach or onCreate, i.e, before the activity is displayed
ActivityResultLauncher<Intent> someActivityResultLauncher = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
#Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
// There are no request codes
Intent data = result.getData();
doSomeOperations();
}
}
});
This is Your Code
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.qr_scanner_layout);
//Button click event to open QR scanner
findViewById(R.id.camera_button).setOnClickListener(v -> {
Intent intent = new Intent(MainActivity.this, QRCodeScanner.class);
intent.putExtra("SCAN_FORMATS", "QR_CODE");
someActivityResultLauncher.launch(intent);
});
}
// You can do the assignment inside onAttach or onCreate, i.e, before the activity is displayed
ActivityResultLauncher<Intent> someActivityResultLauncher = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
#Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
// There are no request codes
Intent data = result.getData();
if (data != null) {
String scannedText = data.getStringExtra("com.journeyapps.barcodescanner.CaptureActivity.SCAN_RESULT");
TextView scannedTextView = findViewById(R.id.scanned_text);
scannedTextView.setText(scannedText);
}
}
}
});
}
If a function is deprecated, the documentation usually tells you why and what you should use instead:
This function is deprecated.
This method has been deprecated in favor of using the Activity Result API which brings increased type safety via an ActivityResultContract and the prebuilt contracts for common intents available in androidx.activity.result.contract.ActivityResultContracts, provides hooks for testing, and allow receiving results in separate, testable classes independent from your activity. Use registerForActivityResult passing in a StartActivityForResult object for the ActivityResultContract.
The other answer shows you the developer guide for using this stuff and has an example, but it's important to always look at the documentation when you run into deprecated stuff - it's rare a function is removed with no information, and sometimes you won't need to worry about the deprecation anyway (e.g. if it only happened with the newest version of Android, meaning they've just decided it will be removed sometime in the future as the older APIs fall out of use)
I Have an activity A that opens an activity B using startActivityForResult.
Now in activity B it's an activity fragment holder as well it contains an ActionBar with menu items.
Now whenever I press action bar button in activity B it should return data from selected fragment of an activity B not to its holder instead it should return data to activity A because it's the one who did the launch.
So it's basically passing data fragment (inside activity B) to activity B then to Activity A.
I am trying hopelessly to find a way to solve it. Is there any possible way to do it?
Disclaimer there are many ways, this is the one I prefer, not the best ever and not the perfect one, I just like this.
The easiest way, in my opinion, is to pass the data from Fragment inside B to ActivityB, then from ActivityB to ActivityA.
Step 1 to pass data from Fragment to container activity you have many ways; the one I usually use is to use an Interface:
Create interface for ActivityB
public interface IActivityB {
void setDataAAndFinish(whateverType data);
}
Implement interface in your activityB
public class InterventoActivity extends AppCompatActivity implements IInterventoActivity {
#Override
protected void onResume() {
super.onResume();
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
private Bundle dataA = null;
#Override
public void setDataAAndFinish(whateverType data) {
dataA = data;
Intent intent = new Intent();
intent.putExtra("data", data)
setResult(RESULT_OK, intent);
finish();
}
}
Set activityA to request and accept return from ActivityB
first, start activityB for result and not normally
Intent i = new Intent(this, ActivityB.class);
startActivityForResult(i, 1);
Then read result
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1) {
if(resultCode == RESULT_OK) {
whateverType data = data.getStringExtra("data");
}
}
}
Now from fragment
((IActivityB)getActivity()).setDataAAndFinish(myDatas);
You need to declare a function in your ActivityB like the following.
public void sendDataBackToActivityA(String dataToBePassedToActivityA) {
Intent intent = new Intent();
intent.putExtra("data", dataToBePassedToActivityA);
setResult(RESULT_OK, intent);
finish();
}
Now from the Fragment that you launched from ActivityB, just call the method on some action in your Fragment that was launched from ActivityB. So the pseudo implementation of the process in your Fragment should look like the following. Declare this function in your Fragment and invoke the function on some action in your Fragment.
public void sendDataToActivityAFromFragment(String dataToBePassed) {
((ActivityB)getActivity()).sendDataBackToActivityA(dataToBePassed);
}
This will serve your purpose I hope.
You can declare static variables in your A activity and set it from the B activity
Or you can make static class and set variables values from B Activity and get it in A activity
Or you can send the menu value from Activity B to A while you exit Activity B and start activity A by using bundle
this is how you set the data to be passed to activity A in activity B
val resultIntent = Intent()
resultIntent.putExtra(DATA, "closed")
setResult(Activity.RESULT_OK, resultIntent)
finish()
this is how you get data in activity A
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == FILE_UPLOAD_CODE) {
when (resultCode) {
Activity.RESULT_OK -> {
// data here is obtained data of the method paramater
}}}}
In your Activity A.Move from activity A to b like this:-
int YOUR_CODE=101; // it can be whatever you like
Intent i = new Intent(getActivity(), B.class);
startActivityForResult(i,YOUR_CODE);
In your Activity B in its fragment
Intent resultIntent = new Intent();
resultIntent.putExtra("NAME OF THE PARAMETER", valueOfParameter);
...
setResult(Activity.RESULT_OK, resultIntent);
finish();
And in your Activity A's onActivityResult() function do this:-
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (resultCode==YOUR_CODE)
{
String value = (String) data.getExtras().getString("NAME OF THE PARAMETER"); //get Data here
}
}
}
In kotlin: -
In class A
startActivityForResult(Intent(context, B::class.java), 143)
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
if (requestCode == 143) {
if (data!!.extras.get("check").equals("0")) {
childpager.currentItem = 0
}
}
}
In Class B
val intent = Intent()
intent.putExtra("check", "0")
setResult(Activity.RESULT_OK, intent)
I have used the following code to get a picture from the gallery in an app on clicking a button. It works fine but I just wanted to know the meaning of the codes used. Could someone help me in it?
private ImageButton mSelectImage;
public static final int GALLERY_REQUEST =1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_post);
mSelectImage = (ImageButton)findViewById(R.id.imageSelect);
mSelectImage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent galleryIntent = new Intent(Intent.ACTION_GET_CONTENT);
galleryIntent.setType("image/*");
startActivityForResult(galleryIntent, GALLERY_REQUEST);
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == GALLERY_REQUEST && resultCode == RESULT_OK){
Uri imageUri = data.getData();
mSelectImage.setImageURI(imageUri);
}
}
This is the requestCode. It helps you to identify from which Intent you came back. For example if you have two or more intent for camera request and for the Contact request.Whenever the subsequently called finish and need to pass data back to Acivity, now you need to identify in your onActivityResult from which intent call you are returning from and put your handling logic accordingly.
public static final int CAMERA_REQUEST = 101;
public static final int CONTACT_VIEW = 202;
#Override
public void onCreate(Bundle savedState)
{
super.onCreate(savedState);
// For CameraRequest you would most likely do
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_REQUEST);
// For ContactReqeuest you would most likely do
Intent contactIntent = new Intent(ACTION_VIEW, Uri.parse("content://contacts/people/1"));
startActivityForResult(contactIntent, CONTACT_VIEW);
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data)
{
if (resultCode == Activity.RESULT_CANCELED) {
// code to handle cancelled state
}
else if (requestCode == CAMERA_REQUEST) {
// code to handle data from CAMERA_REQUEST
}
else if (requestCode == CONTACT_VIEW) {
// code to handle data from CONTACT_VIEW
}
}
GALLERY_REQUEST is a request code which is used like token, imagine you go into mall with bag, but they can't let you in with the bag so you have to put your bag outside the mall and guy will gives you a token, so when you will come back you give him that token and he will give your bag.
This token is managed just because you are not the only one who came with the bag there may be more, as the rule all person have to put their bag outside mall, but how to identify which bag belongs to which person,they used token.
Just like that request code is used, you may going to several other apps via implicit intent from your activity but when you came back, one method called for all intent: onActivityResult now you have request code to identify that from which activity is user coming from.
I am making a music player application, and I am trying to implement playlists. I have a file chooser in another intent, and I would like the ListView in the mainActivity to update when the file chooser intent closes. how can I call my UpdateListView method when it closes?
start intent:
Intent intent = new Intent(this, FileChooser.class);
startActivity(intent);
Closing intent
public void closeButton(View view){
finish();
}
Any help would be appreciated! thanks!
I assume you are using your own FileChoser class, not a standard Android one:
private static final int FileChooserRequestCode = 666;
Intent intent = new Intent(this, FileChooser.class);
startActivityForResult(intent, FileChooserRequestCode);
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == FillChooserRequestCode) {
if (resultCode == Activity.RESULT_OK) {
// ... file is chosen
String fileName = data.getStringExtra("FileName");
} else {
... dialog is closed
}
}
}
in FileChoser you do
Intent intent = new Intent();
intent.putStringExtra("FileName", fileName);
SetResult(Activity.RESULT_OK, intent);
finish();
and
SetResult(Activity.RESULT_CANCELED);
finish();
You can use startActivityForResult() please refer the link Getting Results From Activity
static final int FILE_CHOOSER_INTENT = 1; // The request code
...
private void chooseFile() {
Intent intent = new Intent(this, FileChooser.class);
startActivityForResult(intent, FILE_CHOOSER_INTENT);
}
Call setResult pass your result data as Intent. for details refer link SetResult function
Override this in your calling activity
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// Check which request we're responding to
if (requestCode == FILE_CHOOSER_INTENT) {
// Make sure the request was successful
if (resultCode == RESULT_OK) {
// The user picked a contact.
// The Intent's data Uri identifies which contact was selected.
// Do something with the contact here (bigger example below)
}
}
}
I have 2 activities in my application, Activity1 and Activity2.When the app launches Acitivity1 is the the one that is called.Clicking on a button in Activity1 should take you to Activity2.
In Acivity2,some data processing is done then i send back data to Activity1 using an intent like this:
Intent in=new Intent(getApplicationContext(), Activity1.class);
in.putExtra("data", data);
startActivity(in);
Then getting back to Activity1 i obtain the intent data:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity1);
String data =(getIntent().getExtras().getString("data"));
The problem here is that the first time the app launches it checks for the intent data and it does not exist so i get the nullpointerexception error.how can i make sure it checks for the intent data when Activity2 is the previous class?
You can check if the intent is existing using:
getIntent().hasExtra("data");
This will return you a boolean.
Also if oyu want to return some datas to the first activity, your should start the second one with startActivityForResult
if (extras != null) {
if (extras.containsKey("data")) {
boolean hasData = extras.getBoolean("data", false);
// TODO: Do something with the value of "data".
}
}
put a check over it
if(getIntent().getExtras()!=null){
String data =(getIntent().getExtras().getString("data"));
}
Follow the following steps
1: from your activity1's button click call as follow
Intent i = new Intent(this, SecondActivity.class);
startActivityForResult(i, 1);
2: In your Activity2 set the data which you want to return back to Activity1 as follow and if you don't want to return back don't set anything.
Intent returnIntent = new Intent();
returnIntent.putExtra("result",result);
setResult(RESULT_OK,returnIntent);
finish();
if you don't want to return data:
Intent returnIntent = new Intent();
setResult(RESULT_CANCELED, returnIntent);
finish();
3: now again in your Activity1 handle the return data as follow
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1) {
if(resultCode == RESULT_OK){
String result=data.getStringExtra("result");
}
if (resultCode == RESULT_CANCELED) {
//Write your code if there's no result
}
}
}
EDIT:
and if you strictly want to use your own method as in your question try this:
in your Activity1 you obtain the intent data as:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity1);
String data ="default value";
try{
data =(getIntent().getExtras().getString("data"));
}catch(Exception e){
}
}
use ActvityForResult.
replace these codes.
in ACTVITY1:
put this after onCreate:
#Override
protected void onActivityResult(int requestCode ,int resultCode ,Intent data ) {
super.onActivityResult(requestCode, resultCode, data);
String name =data.getStringExtra("data");
if(resultCode == RESULT_OK){
switch(requestCode){
case 2:
if(resultCode == RESULT_OK){
Toast.makeText(this, name, Toast.LENGTH_LONG).show();
}
}
}
in ACTIVITY2:
Intent intent=new Intent();
intent.putExtra("data",data);
setResult(2,intent);
finish();