Develop Reference

How to pass data from 2nd Activity to first on the click button?

I want to make a app quite similar to contacts app. In the first activity, I want to show my contact list and I have done this. First Activity consists of add new button in which on the click of that button, I want that user enter first and last name and upload an image for the same. I don't know how to navigate between activities so that i get the required answer. Can anyone please help me..??
See the first Activity at: http://postimg.org/image/996iwj5dp/9c92bd46/
and Second Activity at: http://postimg.org/image/wuscpv1tx/fe6f13c4/
on Second activity there is also a button which will make user able to choose a picture from Gallery and thats acts as 3rd Activity. I get confused in getting data from these activities.

You need to implement startActivityforResult() method in first activity.
Follow below steps to perform the operation:
1) On click of the Add new button in your First activity, instead of calling startActivity(), call startActivityforResult() using a unique activity code:
i.e: public static final int FIRST_ACTIVITY_CODE = 0;
In OnClickListener, you need to implement,
Intent m_data = (FirstActivity.this,SecondActivity.class);
m_data.putextra(//any extra data);
startActivityforResult(FIRST_ACTIVITY_CODE,data);
2) Now when you have added another user from the second activity and you want to pass some data from SecondActivity to FirstActivity, then follow below procedure:
Before you finish the SecondActivity after saving the data,
Intent m_data = getIntent();
m_data.putExtra(//data to pass in FirstActivty);
m_data.putExtra(//data to pass in FirstActivty);
.
.
.
setResult(RESULT_OK,m_data);
finish();
3) In the onActivtyResult() of the FirstActivty, do below procedure:
#Override
protected void onActivityResult(int p_requestCode, int p_resultCode, Intent p_data)
{
if(p_requestCode == FIRST_ACTIVITY_CODE && p_resultCode == RESULT_OK)
{
NewData = p_data.getExtras().get(//your data);
// update data
}
super.onActivityResult(p_requestCode, p_resultCode, p_data);
}
Hope this helps you.

Android: Passing data from one activity to another activity in ListView

I am making a Grocery list app.
In my first Activity I have a ListView and in my second activity I can add the new grocery details. I want to show those details in the first Activity's ListView. Now how can I pass data from second Activity to the first Activity in ListView.
In second activity i passed data with fooling code:
EditText editName = (EditText) findViewById(R.id.txtName);
EditText editQty=(EditText) findViewById(R.id.txtqty);
String name= editName.getText().toString();
String quantity=editQty.getText().toString();
Intent returnIntent = new Intent();
returnIntent.putExtra("name",name);
returnIntent.putExtra("quantity",quantity);
setResult(RESULT_OK,returnIntent);
finish();
And in first activity i used that Intent as follows:
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1) {
if(resultCode == RESULT_OK){
Bundle b = data.getExtras();
if ( b!= null ){
String strName=data.getStringExtra("name");
String strQty=data.getStringExtra("quantity");
System.out.println(strName);
System.out.println(strQty);
}
}
if (resultCode == RESULT_CANCELED) {
//Write your code if there's no result
}
}
Please help me solve this. Thanks in advance.

I suggest you to use SQLite for your issue, when you insert new grocery details, just create one table and insert that details in database table. Now , when you want to display that newely added details, just run "select" query and set your ListView Adapter.
If everytime you do not want to set your adapter, then just maintain one boolean static variable like isGroceryAdded. If grocery details added successfully, at that time make that boolean variable "true". And check in your first activity that is that variable is true, then run query again and set your adapter again, after setting the adapter, just make that variable false again.

Without having some code, my suggestion would be to create a model class that implements serializable, put that in the intent as a result and pass it back to the first Activity (note for this to work, the second activity has to be started with startActivityForResult()).
For a similar question, please have a look at https://stackoverflow.com/a/14333555/1082942

This is a general overview of one solution that should work in most cases. Considering you didn't provide code specific to your situation this may or may not be what you need.
1) To resume the first activity, send an intent from the second activity to the first activity containing the grocery details as intent extras (key-value pairs).
2) Override the first activity's onResume() method to handle the incoming intent to pull out the data you want.
3) Then you need to update the data used by your adapter with this intent extra information.
4) Then you need to call notifyDataSetChanged() on your adapter so it will recreate its views with the updated info
Hope you find this helpful.

Send data to activity which is running in background

Having trouble passing data between activities.
ListActivity is collecting data and when back button is pressed returns to MainActivity and then want to get that data via onResume method but I don't get anything.
How can this problem be solved?
ListActivity.java
#Override
public void finish() {
i = new Intent(ArrayListActivity.this, MainActivity.class);
i.putParcelableArrayListExtra(Constants.TAG_SELECTED_PRODUCT_LIST, selected_list);
super.finish();
}
MainActivity.java
#Override
protected void onResume() {
super.onResume();
Bundle extras = getIntent().getExtras().getBundle(Constants.TAG_SELECTED_PRODUCT_LIST);
if(extras != null) {
selected_list = extras.getParcelableArrayList(Constants.TAG_SELECTED_PRODUCT_LIST);
myListView.setAdapter(new ProductAdapter(MainActivity.this,
R.layout.array_lisviewt_item_row, selected_list));
}
}

You probably want to start your second activity from the first one via the startActivityForResult(...) method.
This method allows you to transport results from a launched activity back to it's launching activity.
From the documentation:
Launch an activity for which you would like a result when it finished.
When this activity exits, your onActivityResult() method will be
called with the given requestCode. Using a negative requestCode is the
same as calling startActivity(Intent) (the activity is not launched as
a sub-activity).

You'll want to start the activity with startActivityForResult() and override onActivityResult() to handle the data you return from the second Activity.
Check out this article on the Android developers site for more info.

Perhaps you should
Call your ListActivity with startActivityForResult(), from your MainActivity.
Once you finished working on the ListActivity, you call setResult() to set the data, followed by finish().
This will bring you back to your previous MainActivity. So how do you retrieve the data set by your ListActivity?
In MainActivity, override onActivityResult().
There's a brief explanation of this mechanism in Starting Activities and Getting Results.

Interaction between activities

I start an activity from the main one using a Intent:
Intent i = new Intent(getApplicationContext(), InfoChiamata.class);
i.putExtra("codice_cliente", codice_cliente[tv_clicked_id]);
i.putExtra("descrizione_chiamata", descrizione_chiamata[tv_clicked_id]);
startActivity(i);
How can I edit the main activity ui from the activity started whit Intent?
How can I know when i return back from the second activity to the main one? I tried to Override the onResume and onStart method but the application doesn't even start. I tryed to override onRestart method when it get called the application crash.
#Override
protected void onRestart() {
if(call_back == 1)
Toast.makeText(getApplicationContext(), "asd", Toast.LENGTH_LONG).show();
}
call_back variable is set to 1 from the secondary activity, when it is launched.
Thanks, Mattia

try startActivityForResult instead which gives you a callback to your first activity. also don't use the application context, unless absolutely necessary, use the activity context instead. Also when you call certain methods from the activity class and override them like onRestart or onStop or onResume you have to do super.onResume() inside the method first, making sure that the app life cycle is not broken.

Try starting your new Activity with
startActivityForResult(i, 1);
Then, in your main activity, use this code to catch when the user leaves the second activity and returns to the first one:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
//your request code will be 1 since you started the
//activity with result 1. Your result code will be detemined
//by if the activity ended properly.
}

It sounds like maybe you want to use startActivityForResult(Context, Intent) to call your second activity. When you do this, your second activity can return a value to the activity that called it, and you can decide what to do from there. When the second activity is finished your first activity will receive a callback. This tells your first activity that the second one is finished and it is passed the result of what happened in the second activity.
It is explained in the Android docs here: http://developer.android.com/reference/android/app/Activity.html#startActivityForResult(android.content.Intent,%20int)

Custom View calling startActivityForResult

I created custom compound view where I incorporate functionality to take pictures.
I'm calling it like this (from view):
Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
((Activity)mContext).startActivityForResult(intent, index);
This part works good. What I don't know how to do is how do I implement onActivityResult inside my custom view?
Or should I catch this inside Activity and than re-route into my view? Doesn't look like very nice solution..

You actually can do it like this:
#Override
public void onClick(View v) {
final FragmentManager fm = ((FragmentActivity) getContext()).getSupportFragmentManager();
Fragment auxiliary = new Fragment() {
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
//DO WHATEVER YOU NEED
super.onActivityResult(requestCode, resultCode, data);
fm.beginTransaction().remove(this).commit();
}
};
fm.beginTransaction().add(auxiliary, "FRAGMENT_TAG").commit();
fm.executePendingTransactions();
auxiliary.startActivityForResult(new Intent(getContext(), ToStartActivity.class), 3333);
}
The trick is using an auxiliary temp fragment.

I'm having the same issue, as the initial question. I know that you all posted working solution, BUT, all the solutions lack one thing: encapsulation. What do I mean - If in one activity I have 10 views that should (on some event) start another activity it should be NORMAL to be able to start that new activity from the view that needs that activity. You all are trying to convince that is better to handle all new possible activites from the initial one - than why we added different logic in each view. We may want to RE-USE code, and create one custom view that can work INDEPENDENT to where we use it (work may include showing another activity to select something for example).
I know that this is not possible (or not yet), and is a clear proof that Android SDK is not ready yet to handle real big applications.
If you want an example:in any real business app that has for example, customer list (that should be a view) ,the view should be able to launch by itself addcustomer activity, edit customer activity and so on, independent from where you put that customer list view (control) - because in big apps you need to RE-use components (you may need to show the customer list control in a order product activity, in a timesheet activity and so on.).
One possible solution could be:
- start the new activity (using the view context (normally should be the parent activity).
- on the new activity closing event, either call directly a method in the calling view (depending on the case, and posibilities: either static that is handling the code that you normally would run on activityresult, either try to pass the instance of the calling view to the new activity, and do the same. In this way, you can handle your new activity, without letting the containing activity to know anything about it.

You need to catch this from your activity. The startActivityForResult is called on your activity, so it'll be the one launching the Intent and getting the result. I'd say that it's overall bad to launch it directly from the view's code. A better solution would be with a clickListener (or checkChangeListener, or whatever you want), set by your activity, and calling a method like "openImageCapture".
When the Intent returns, your activity will take care of the result and update your views as needed.
Views are there just for displaying stuff on the screen and getting user input, the activity is there to do the actual work.

Here's a static function to implementing #riwnodennyk's solution, while overcoming the Fragment must be static and not in anonymous class error:
public static void myStartActivityForResult(FragmentActivity act, Intent in, int requestCode, OnActivityResult cb) {
Fragment aux = new FragmentForResult(cb);
FragmentManager fm = act.getSupportFragmentManager();
fm.beginTransaction().add(aux, "FRAGMENT_TAG").commit();
fm.executePendingTransactions();
aux.startActivityForResult(in, requestCode);
}
public interface OnActivityResult {
void onActivityResult(int requestCode, int resultCode, Intent data);
}
#SuppressLint("ValidFragment")
public static class FragmentForResult extends Fragment {
private OnActivityResult cb;
public FragmentForResult(OnActivityResult cb) {
this.cb = cb;
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (cb != null)
cb.onActivityResult(requestCode, resultCode, data);
super.onActivityResult(requestCode, resultCode, data);
getActivity().getSupportFragmentManager().beginTransaction().remove(this).commit();
}
}
Usage example:
Intent inPhonebook = new Intent(Intent.ACTION_PICK, ContactsContract.CommonDataKinds.Phone.CONTENT_URI);
myStartActivityForResult((FragmentActivity) getContext(),
inPhonebook, REQUEST_CODE_PICK_CONTACT, this::onContacts);

There is no way to catch onActivityResult from your view, only from Activity.
And its not safe to assume that's Context object is Activity. In general you should not rely on this fact. Even if it seems reasonable in case with views, you still should use only methods available trough Context interface. That's because your can't predict all side-effects on the Activity, when you're calling Activity specific functions.

Just make the same method inside your custom view
And inside the activitys onActivityResult call yourView.onActivityResult(...) and process the result inside your view..
Also as guys mentioned you must not always end up with Context being of Activity class. Usually when it is from inflated view.
But if you construct your view only in code and always use the activity instance you are good.