Develop Reference

Can I pass an Intent extra on finish()?

I'm wondering, is it possible to send information to the activity that I return to after calling finish()?
For example, I have an Activity SendMessageActivity.class which allows the user to post a message to their feed. Once that message has been saved to the server, I call finish(). Should I instead just start my MainActivity.class with a new Intent? Or is it better for life cycle development to just finish SendMessageActivity.class?
I don't see the point of starting a new activity since closing the current one will always bring you back to MainActivity.class. How can I just send a String extra after finishing the current Activity?

Use onActivityResult.
This might help you to understand onActivityResult.
By using startActivityForResult(Intent intent, int requestCode) you can start another Activity and then receive a result from that Activity in the onActivityResult() method.So onActivityResult() is from where you start the another Activity.
onActivityResult(int requestCode, int resultCode, Intent data) check the params here. request code is there to filter from where you got the result. so you can identify different data using their requestCodes!
Example
public class MainActivity extends Activity {
// Use a unique request code for each use case
private static final int REQUEST_CODE_EXAMPLE = 0x9988;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Create an Intent to start AnotherActivity
final Intent intent = new Intent(this, AnotherActivity.class);
// Start AnotherActivity with the request code
startActivityForResult(intent, REQUEST_CODE_EXAMPLE);
}
//-------- When a result is returned from another Activity onActivityResult is called.--------- //
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// First we need to check if the requestCode matches the one we used.
if(requestCode == REQUEST_CODE_EXAMPLE) {
// The resultCode is set by the AnotherActivity
// By convention RESULT_OK means that what ever
// AnotherActivity did was successful
if(resultCode == Activity.RESULT_OK) {
// Get the result from the returned Intent
final String result = data.getStringExtra(AnotherActivity.EXTRA_DATA);
// Use the data - in this case, display it in a Toast.
Toast.makeText(this, "Result: " + result, Toast.LENGTH_LONG).show();
} else {
// AnotherActivity was not successful. No data to retrieve.
}
}
}
}
AnotherActivity <- This the the one we use to send data to MainActivity
public class AnotherActivity extends Activity {
// Constant used to identify data sent between Activities.
public static final String EXTRA_DATA = "EXTRA_DATA";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_another);
final View button = findViewById(R.id.button);
// When this button is clicked we want to return a result
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// Create a new Intent as container for the result
final Intent data = new Intent();
// Add the required data to be returned to the MainActivity
data.putExtra(EXTRA_DATA, "Some interesting data!");
// Set the resultCode to Activity.RESULT_OK to
// indicate a success and attach the Intent
// which contains our result data
setResult(Activity.RESULT_OK, data);
// With finish() we close the AnotherActivity to
// return to MainActivity
finish();
}
});
}
#Override
public void onBackPressed() {
// When the user hits the back button set the resultCode
// to Activity.RESULT_CANCELED to indicate a failure
setResult(Activity.RESULT_CANCELED);
super.onBackPressed();
}
}
Note : Now check in MainActivity you startActivityForResult there you specify a REQUEST_CODE. Let's say you want to call three different Activities to get results.. so there are three startActivityForResult calls with three different REQUEST_CODE's. REQUEST_CODE is nothing but a unique key you specify in your activity to uniquely identify your startActivityForResult calls.
Once you receive data from those Activities you can check what is the REQUEST_CODE, then you know ah ha this result is from this Activity.
It's like you send mails to your lovers with a colorful covers and ask them to reply in the same covers. Then if you get a letter back from them, you know who sent that one for you. awww ;)

You can set result of an activity, which allow you to data into an initent.
In your first activity, call the new one with startActivityForResult() and retrieve data in method onActivityResult. Everything is in documentation.

try this:
in First Activity:
Intent first = new Intent(ActivityA,this, ActivityB.class);
startActivityForResult(first, 1);
Now in Second activity: set Result during finish()
Intent intent = new Intent();
intent.putExtra("result",result); //pass intent extra here
setResult(RESULT_OK,intent);
finish();
First activity Catch the result;
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
// check if the request code is same as what is passed here it is 1
if(requestCode==1)
{
String message=data.getStringExtra("result");
//get the result
}
}

If you call finish() to avoid that the user go back to SendMessageActivity.class, you can set this flags to your intent:
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
This will open the MainActivity and remove the SendMessageActivity from the activities stack.

Custom RecyclerAdapter and startActivityForResult

I have a Fragment that contains a RecyclerView which uses a custom RecyclerAdapter. I have an onClickListener inside my custom RecyclerAdapter - when a position is clicked I want it to start startActivityForResult. So far this works in as such as when it is clicked it starts the Activity as desired. However when I press the back button to go to the Fragment containing the RecyclerView onActivityResult is never called. I have passed in a context to the custom RecyclerAdapter. Is this something that is possible? Or does the Activity/Fragment initiating startActivityForResult be the one that intercepts it? If not I will end up handling the onClick in the Fragment with a gesture detector or something similar, but before that I wanted to give this a fair crack! Note: I have included onActivityResult in the MainActivity which has the Fragment container so the Fragment does receive onActivityResult if startActivityForResult is initiated from the Fragment. My code:
RecyclerAdapter onClickListener:
#Override
public void onClick(View v) {
String titleId = titlesListDataArrayList.get(getLayoutPosition()).getTitle_id();
Intent intent = new Intent(context, CreateItemsActivity.class);
intent.putExtra("TITLE_ID", titleId);
((Activity) context).startActivityForResult(intent, Constants.NEW_ITEMS_REQUEST_CODE);
}
CreateItemsActivity.class - onBackPressed()
#Override
public void onBackPressed() {
Intent intent = new Intent();
setResult(Constants.NEW_ITEMS_REQUEST_CODE, intent);
finish();
}
MyListsFragment.class (contains RecyclerView)
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
Log.e("CALLED", "OnActivity Result");
// if requestCode matches from CreateItemsActivity
if (requestCode == Constants.NEW_ITEMS_REQUEST_CODE) {
Log.e("REQUEST CODE", String.valueOf(requestCode));
populateRecyclerView();
}
}
Also I have this in the MainActivity:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// included to allow fragment to receive onActivityResult
}

Your calling Activities onActivityResult will only be called when the second activity finishes and a setResult has been executed.
Since the user is hitting the back button the 2nd activity is finishing without setResult being called.
You'll need to override onBackPressed so you can execute your setResult code.
I see you have implemented this but I think the crux of the issue is that you need to return Activity.RESULT_OK not your request code.
#Override
public void onBackPressed() {
Intent intent = new Intent();
setResult(RESULT_OK, intent);
super.onBackPressed();
}
In this case you don't need to explicitly return your requestCode of Constants.NEW_ITEMS_REQUEST_CODE because Android will forward that automatically.

OK, so IF by any chance somebody else has this problem here is my
solution. I added this code into the MainActivity onActivityResult (note I have a frame container which is where all fragments are inflated):
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// get current fragment in container
Fragment fragment = getSupportFragmentManager().findFragmentById(R.id.frameContainer);
fragment.onActivityResult(requestCode, resultCode, data);
}
I believe this works as the MainActivity is top in the hierarchy and intercepts the onActivityResult, so basically I just point it where I want it to be used.

Android, Get result from third activity

In first activity, there is empty ListView and Button.
When I press button, it starts second activity that has ListView of categories.
After I click into one of listElements it will start third activity that has ListView with elements that are belong to my chosen category.
When I choose element of third ListView it must send me back to first activity, where my chosen element is added to my empty ListView

Use Intent.FLAG_ACTIVITY_FORWARD_RESULT like this:
FirstActivity should start SecondActivity using startActivityForResult().
SecondActivity should start ThirdActivity using this:
Intent intent = new Intent(this, ThirdActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_FORWARD_RESULT);
startActivity(intent);
finish();
This tells ThirdActivity that it should return a result to FirstActivity.
ThirdActivity should return the result using
setResult(RESULT_OK, data);
finish();
At that point, FirstActivity.onActivityResult() will be called with the data returned from ThirdActivity.

Though I'd implore you to change your architecture design, it is possible to do it like this:
File ActivityOne.java
...
startActivityForResult(new Intent(this, ActivityTwo.class), 2);
...
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if(resultCode == RESULT_OK && data != null) {
//Collect extras from the 'data' object
}
}
...
File ActivityTwo.java
...
startActivityForResult(new Intent(this, ActivityTwo.class), 3);
...
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if(resultCode == RESULT_OK && data != null) {
setResult(resultCode, data);
finish();
}
setResult(RESULT_CANCELLED);
}
...
File ActivityThree.java
...
//Fill the Intent resultData with the data you need in the first activity
setResult(RESULT_OK, resultData);
finish();
...

How to destroy previous activity

So I have 2 activities lets say A and B. A navigates to B, I want the activity A to be killed or make it unusable/unseen when directed from B.
so it should be like when I press the back button on B activity it should not open activity A instead it should go to the app tray.
also activity A should comeback when I clear the application data
thanks.

You could do this in one of two ways. First is finishing ActivityA so that it can't be resumed to later. When starting ActivityB from ActivityA, you'd do something like this:
Intent intent = new Intent(this, ActivityB.class);
startActivity(intent);
this.finish();
Another way is to just finish ActivityA when it gets a result of any sort from ActivityB. This code would also be in ActivityA.
To start ActivityB:
Intent intent = new Intent(this, ActivityB.class);
startActivityForResult(intent, REQUEST_ACTIVITYB);
To make sure ActivityA doesn't resume:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == REQUEST_ACTIVITYB) {
finish();
}
}
REQUEST_ACTIVITYB is just an int of your choosing.

activity not sending result when pressing back button

i am using following code to start my activity
public void onClick(View v) {
Intent myIntent = new Intent(v.getContext(), AddReceipt.class);
startActivityForResult(myIntent, RECEIPT_ADDED);
}
Now i want to get arrays from addreceipt class or data from my child activity
public synchronized void onActivityResult(final int requestCode, int resultCode, final Intent data) {
if (resultCode == Activity.RESULT_OK)
{
if (requestCode == RECEIPT_ADDED)
{
String abc = "abs";
}
}
}
when calling this function, it returns data as null and result code as 0. How can i get my data from my child activity.
BesT Regards

To get results from a sub-activity you need to call the setResult() method inside your sub-activity, passing the result code and possibly any amount of data inside an Intent object. Then you can catch this Intent in the onActivityResult() of your main activity. Hope this helps.

To pass data from child activity to parent activity use the following code:
Intent intent= childActivity.getIntent();
intent.putExtra("key","value");
childActivity.setResult(Activity.RESULT_OK, intent);
childActivity.finish();
if value is an list of object use Serializable .
Now if you press back button , onActivityResult method of parent class will be called and you will get RESULT_CANCEL.