My app starts up at Activity A which contains a ListView. The ListView can have items added to it if the user hits "Add" button and goes to Activity B.
In Activity B they fill out some forms and hit "OK" button which takes them back to Activity A where the new item is added to the ListView.
I have a finish() method after going from B to A -- but NOT the other way around.
So if you hit back three times after adding three items. It will just repeat the ListView (Activity A) over 3 times -- less one item that was added.
What is the best way in doing this? I can't put a finish method on the "Add" Button (going from A to B) because if you are in Activity B, it will close the app instead of taking you back to A -- which I do not want. That is, if the user changes his mind and doesn't want to "Add new item" by hitting "OK" while in B. Is a manual Back button the only answer?
Start Activity B by using startActivityForResult() and finish activity B after filling the form.
EDIT
When you startActivityForResult(), you pass 2 parameters, namely intent and requestcode. After you are finished with the new activity(in your case Activity B) you use a function setResult(RESULT_OK) to signify that the operation in Activity B was successful and then you call finish(). After the call to finish() the Activity B will return to Activity A and will call onActivityResult(int requestCode, int resultCode, Intent data). The parameter requestcode helps in identifying which particular activity/request has returned.
Hope this explanation helps you.
Related
How can I preserve data between activities? For instance, I have an edit text and a button in Activity A. I fill in that editText and then click on the button. That button starts a new intent, Activity B. In B there are several buttons, but all of them if clicked on, start activity A again. I want that editText to be still filled in as well as pass specific data to Activity A depending on the button pressed in Activity B.
I know this has to do with onStop() -> onStart(), but couldn't get it to work.
You should start Activity B with startActivityForResult. Then, when u set the result, you should "catch" it in Activity A by overriding onActivityResult().
As for EditText, if you don't call finish() on Activity A - you don't need to override onSaveInstanceState or anything else - system does it for you.
Don't finish the activity in Activity A intent to Activity B. and use startActivityForResult(intent) rather than startActivity(intent) to be able to pass the data back to activity A again. check this answer to how How to manage `startActivityForResult` on Android?.
In my android apps i have four activity A->B->C->D and in every activity i call web service then update the list-view and other element from the server so suppose i did delete some data from the database for Activity A and if user access the Activity B and he press the back button then Activity A should be refreshed. I did override onResume method and check the data is updated or not but didn't worked. I also tried another way but not achieve my goal.
my Activity structure is like a following
Class A Is Fragment which is having two tab and each tab contain listview
Class B Is Activity
Class C Is Activity
Class D Is Activity
I don't understand how to call web service again when press the back button and how to update fragment and activity when user press the back button. Please anybody suggest me some answer.
Thanks in advance
you can override the OnBackPressed-method. check the top-answer on that link!!
Android: Proper Way to use onBackPressed() with Toast
Start activity B from activity A with "startActivityForResult" instead of "startActivity".
In activity B you defaultly return RESULT_CANCELED -> so setResult(RESULT_CANCELED). Only when activity B is finished on purpose you return RESULT_OK.
In activity A you then just need to implement onActivityResult(). Depending on the result returned from activity B you can then do specific stuff in activity A, in your case refresh something.
Here is an example: http://www.vogella.com/articles/AndroidIntent/#usingintents_sub
In my app, whenever calling the finish() method, wherever it was, I am not taken to the previous activity, rather I am directed to mainActivity.
finish();
My aim is, showing the user the activity just before the current activity he is seeing.
Question 1 : How can I make finish() always take me to the activity before ?
Question 2 : Does this work using another workaround other than finish() ?
Question 3 : How to check the stack of activities and decide accordingly which one to go to ?
If you have written finish in each intermediate activity, that means you are removing the activity from the stack, hence on finishing an activity you are taken to the last non-finished activity, hence write finish() in only that activity which you do not want to see until the same workflow is followed and its onCreate() is called
if you start activity c from b and b from a if you use the back button on your phone at activity c it will go to b and back button press in b it will show a. if you use finish in all the 3 activities what happens is a calls b and a is finished and b calls c and b is finished so when you use finish in c it will not have b to show. so you have to tell where you are placing your finish based on some condition or a button click or just before starting a new activity, post your code and we will help you.
I have 3 different activities in a TabGroupActivity. Let's say A - Parent, B - Child 1, C - Child 2.
A --- starts --> B
B --- starts --> C
and I have an alert dialog in C which shows some message. I want to go back to activity A when I press Ok button on dialog.
But the problem is that I can open activity C from other activities too and I want to go back to their parent activities too. So I need to make something which will work no matter which activity opens C. I've tries with this one but didn't work :
Intent intent = new Intent(Synchronization.this,Synchronization.this.getParent().getClass());
but it didn't help me. Any suggestions?
You just have to make use of two Activity methods viz. startActivityForResult() and onActivityResult()
Example : http://www.vogella.de/articles/AndroidIntent/article.html#explicitintents
Here goes the logic :
In ActivityB
Start ActivityC by using startActivityForResult(activityCIntent,INT_CODE);
In ActivityC
Now check if Dialog's OK Button is pressed, if yes then set the result using setResult(RESULT_OK,intent); and then call finish();
Then control will be redirected to ActivityB's onActivityResult() method.
Now inside onActivityMethod() check whether result_code==RESULT_OK and requestCode = INT_CODE. If yes then simply call finish();
In the Activity B start the C Activity as startActivityForResult() so when you finish the C activity it will back to the B with result. As the result you may pass flag with the intent object.
Now when you finish the C activity with ok button then set the result as RESULT_OK into the setResult() if you need to pass the data back to the B activity you may set the data into the Intent add this intent with the setResult() method and then finish the C Activity.
Now in B check the requestcode is from the C then finish this Activity. As you start this C Activity you can also start the B Activity for the A Activity.
And you need to override onActivityResult() in B activity and if you start the B Activity as for result then also you need to define also into A Activity
am having a two activities that interact.
activity A picks input values and sends to activity B for the user to confirm input before submitting. activity B should allow the user to go back to activity A to edit input values if required or submit the values if they are ok. If user submits values, activity A should be finished and if he edits, then he goes back to activity A.
I have used startActivityForResult() and setResult() methods to kill the activity A when the user submits the values that has worked perfectly, but when i click the edit button to return to activity A, it call the activity A using a new Intent, and subsequently, it starts the activity A, yet previously started activity A is still running . what i want is to resume the activity A where it was left with the existing values before activity B started on click of the back button. How do i achieve this?? Your assistance is highly appreciated
Call finish() in Activity B when you need to edit. There is no need to fire an intent that creates new instance of Activity A. It will resume Activity A.