Develop Reference

Start activity for result not work, between different activities

I have the main page where the photo is loaded, depending on what the array on the other page contains, in order to synchronize them I used StartActivityForResult();.
It will works like this: MainActivity has a photo, i press showMore button(open showMoreActivity), at showMoreActivity change text and after i finish showMoreActivity, MainActivity load the new photo depends on new text, but real it doesn`t change photo.
Can you help me? Where the mistake is?
buttonShowMore.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(getActivity(), ShowMore.class);
onStop();
getActivity().startActivityForResult(intent, 1);
}
});
onClick button ShowMore Listener
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (data == null) {return;}
String dataStringExtra =data.getStringExtra("name1");
Picasso.get().load( dataStringExtra + ".jpg").into(imageViewFirstOfCurrentList);
}
onActivityResult method
Intent intent = new Intent();
intent.putExtra("name1", List.get(0).toString());
setResult(RESULT_OK, intent);
finish();
when close showMore Activity

try removing call to onStop() in your onClick() method

Passing the selected object to an Another Activity

I have a news activity in which there is a list of news.I want a user to select a news from the list and direct him to the news_details page where I give the details about the selected news, however when the user selects the news, program goes quickly to news_details and comes back again to the news.
News:
public void Listen() {
list.setOnItemClickListener(new AdapterView.OnItemClickListener() { // ana sayfada herhangi bir item seçildiğinde
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
NewsItem selectedNews = (NewsItem) parent.getItemAtPosition(position);
Intent i = new Intent(MainActivity.this, News_Details_Activity.class);
i.putExtra("title", selectedNews.getTitle());
i.putExtra("date", selectedNews.getNewsDate().toString());
i.putExtra("image_id", selectedNews.getImageId());
i.putExtra("text", selectedNews.getText());
setResult(RESULT_OK, i);
startActivity(i);
}
});
}
News_Details:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_news__details);
Intent i = new Intent(this,MainActivity.class);
startActivityForResult(i, GET_NEWS);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == GET_NEWS) { // Check which request we're responding to
if (resultCode == RESULT_OK) { // Make sure the request was successful
title.setText(data.getStringExtra("title"));
date.setText(data.getStringExtra("date"));
news_img.setImageResource(data.getIntExtra("image_id", 0));
news_text.setText(data.getStringExtra("text"));
}
}
}
}

First of all, remove this line:
setResult(RESULT_OK, i);
Also, remove this line from newsdetails activity:
startActivityForResult(i, GET_NEWS);
Make changes as below:
public void Listen() {
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
NewsItem selectedNews = (NewsItem) parent.getItemAtPosition(position);
Intent i = new Intent(MainActivity.this, News_Details_Activity.class);
i.putExtra("title", selectedNews.getTitle());
i.putExtra("date", selectedNews.getNewsDate().toString());
i.putExtra("image_id", selectedNews.getImageId());
i.putExtra("text", selectedNews.getText());
startActivity(i);
}
});
}
Then, in your news details activity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_news__details);
Intent i = getIntent();
String title = i.getStringExtra("title");
String date = i.getStringExtra("date");
int imageId = i.getIntExtra("image_id");
String text = i.getStringExtra("text");
}
OnActivityResult method is not required so simply remove it.
FYI:
startActivity and startActivityForResult both of them start new activities , but startActivityForResult as the name suggests that you are expecting a result from the activity you are starting. And this result shall be obtained in onActivityResult method.
Say for example, you want to start Activity2 from Activity1, and you want to pass some data back to Activity1 while finishing Activity2. You simply set the Result in Activity2 using setResult() method. and while Activity1 resumes again, its onActivityResult() will be invoked, you will override onActivityResult() in Activity1 to receive the Result set by Activity2.
Hope you are now clear on this.

Remove these lines
setResult(RESULT_OK, i);
Intent i = new Intent(this,MainActivity.class);
startActivityForResult(i, GET_NEWS);
Use google Gson for serializing the object.
NewsItem selectedNews = (NewsItem) parent.getItemAtPosition(position);
String strNews = new Gson().toJson(selectedNews);
Intent i = new Intent(MainActivity.this, News_Details_Activity.class);
i.putExtra("news", strNews);
startActivity(i);
On other hand News details onCreate() do this
Bundle bundle = getIntent().getExtras();
String newsStr = bundle.getString("news");
Gson gson = new Gson();
Type type = new TypeToken<NewsItem>() {
}.getType();
NewsItem selectedNews = gson.fromJson(newsStr, type);

to send string value
NewsItem selectedNews = (NewsItem) parent.getItemAtPosition(position);
Intent i=new Intent(MainActivity.this, News_Details_Activity.class);
i.putExtra("title", selectedNews.getTitle());
i.putExtra("date", selectedNews.getNewsDate().toString());
i.putExtra("image_id", selectedNews.getImageId());
i.putExtra("text", selectedNews.getText());
startActivity(i);
to recieve in News_Details_Activity
Intent i = getIntent();
title = i.getStringExtra("title");
date= i.getStringExtra("date");
text= i.getStringExtra("text");

you can do it using Serializable by following way
public class News implements Serializable{
String title;
String desc;
String time,imageUrl;
}
Then News List activity
Intent i = new Intent(MainActivity.this, News_Details_Activity.class);
i.putExtra("news",newsObject);
and get it onCreate of NewsDetail
News news=(News) getIntent().getExtras().getSerializable("news");
and user it like title.setText(news.getTitle());

make News class that implements Serialazable
Create new Object of News class , and put into intent as putSerialazable();
in your second activity just getIntent().getSerialazable("key") and set your data to views.

TWO ways data binding between activities

I've 2 activities, and need the main Activity to send some data to the second Activity then the second activity analyze this data and send response back, so I've the below 2 codes:
Main Activity:
import static tk.zillion.mobile.SecondActivity.EXTRA_STUFF;
public class MainActivity extends Activity {
private static int PICK_CONTACT_REQUEST = 0;
private static final int SECOND_ACTIVITY_RESULT_CODE = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Start the SecondActivity
Intent intent = new Intent(MainActivity.this, SecondActivity.class);
intent.putExtra(Intent.EXTRA_TEXT, "my text");
startActivityForResult(intent, SECOND_ACTIVITY_RESULT_CODE);
finish();
}
// This method is called when the second activity finishes
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
Toast.makeText(this, "I'm the Main activity", Toast.LENGTH_SHORT).show();
// check that it is the SecondActivity with an OK result
if (requestCode == SECOND_ACTIVITY_RESULT_CODE) {
if (resultCode == RESULT_OK) {
// get String data from Intent
String returnString = data.getStringExtra(EXTRA_STUFF);
// set text view with string
Toast.makeText(this, "I'm the Main activity", Toast.LENGTH_SHORT).show();
}
}
}
and the Second Activity is as below:
public class SecondActivity extends Activity {
static final String EXTRA_STUFF = "tk.zillion.mobile.EXTRA_STUFF";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = new Intent();
String s = getIntent().getStringExtra(Intent.EXTRA_TEXT);
Toast.makeText(this, "I'm the second activity " + s , Toast.LENGTH_SHORT).show();
Bundle basket =new Bundle();
basket.putString(EXTRA_STUFF, s);
intent.putExtras(basket);
setResult(RESULT_OK, intent);
finish();
}
}
The second activity is fired correctly, and receive the data from the main one, but once the data is sent back the onActivityResult is not fired!!
How can I solve it? thanks

Remove the finish() call that comes after startActivityForResult(). You prevent the oncoming activity to give a result back, because you remove your MainActivity with finish() from the back task.

Dont call finish() after startActivityForResult otherwise that instance of MainActivity that started the second one will be destroyed

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.

How to start an activity which calls a method from a different class?

I have an activity which transfer a string datatype to another activity which then uses that string and calls a method from another class which returns a string. I want to use that method to display the string in the current activity.
So visually it goes (activity 1) -- string--> (activity 2). Activity 2 uses that string to call a method in a different java class which returns a type string which i want to display on the screen along with a few buttons.
So some pseudo code:
say The method in a different java class is:
public static String getStringexample(String n) {
return "hello" + " " + n;
}
and my activity class is:
public class manage extends Activity {
protected void onCreate(bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContainerView(R.layout.activity_manage);
Intent intent = getIntent();
String example = intent.getExtras().getString("intentid");
i'm lost after this..not sure how to use what i got from the intent to display it on the screen in java code.

Information between activities is passed in 'extras'. That is just a collection of string keys and values.
Both sides need to use the same keys, so define static final strings with they keys that your destination activity expects.
Then read the values from the extras using the key and go from there:
public class DestinationActivity extends Activity {
// let your callers know how to pass you the information you need
public static final String EXTRA_N = "n";
private TextView resultText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_destination);
resultText = (TextView) findViewById(R.id.resultText);
// get the information you was passed
Intent intent = getIntent();
String n = intent.getStringExtra(EXTRA_N);
// do your transformation using the other class
String example = DifferentClass.getStringexample(n);
// display the transformed string
resultText.setText(example);
}
// ...
}
The calling activity sends the information like this:
Intent intent = new Intent(this, DestinationActivity.class);
intent.putExtra(DestinationActivity.EXTRA_N, "foo");
startActivity(intent);
Good luck

You can start activity as
Intent i = new Intent(this, SecondActivity.class);
startActivityForResult(i, 1);
Then return to first activity from second activity
Intent returnIntent = new Intent();
returnIntent.putExtra("result",yourdata);
setResult(RESULT_OK,returnIntent);
finish();
In your first activity you will get result by using below code
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
}
}
}