Develop Reference

Starting multiple activities and getting result before starting the next one

I am making a quiz app, my MainActivity(main menu) launches QuestionActivity using startActivityForResult, in QuestionActivity (Question text and answer buttons). After the user has answered the question, I want to send a boolean back a to MainActivity to update the score which then can be pushed into the next intent, in the Question Activity, I display the score in the Actionbar.
The problem is when I answer one question, setResult and Finish Runs but onActivityResult does not, after I answer all questions then OnActivityResult runs 10 times.
How can I get onActivityResult to run after I answer each question, not at the end?
Do I need to use intent flags?
Extra Info
In MainActivity, when the user starts the quiz:
//Called when user clicks quiz
//Creates the list of questions and then asks them.
public void makeQuiz(View view) {
//Pick the questions for the quiz
question[] quiz = new question[10]; //A quiz with 10 questions
for (int i = 0; i < quiz.length; i++) {
quiz[i] = myDBHelper.pickQuestion();
askQuestion(view, quiz[i],i,qscore);
Log.d("Asked question", Integer.toString(i));
}
}
Ask Question is used to start the QuestionActivity:
//Creates a question and then passes it though to the question view.
public boolean askQuestion(View view, question q, int questionNum, int qscore){
question q1 = q;
Log.d("Correct Ans",q.CorrectAns);
Intent question = new Intent(this, QuestionActivity.class);
Bundle extras = new Bundle();
extras.putString("QUESTION", q.QuestionText);
extras.putString("MODULE", q.Module);
extras.putString("CORRECT_ANS",q.CorrectAns);
extras.putString("ANS1", q.WAns[0]);
extras.putString("ANS2", q.WAns[1]);
extras.putString("ANS3", q.WAns[2]);
extras.putInt("qscore",qscore);
question.putExtras(extras); //Passing the question to the QuestionActivity
startActivityForResult(question,1);
return true;
}
In QuestionActivity, When the user answers the question correctly:
//Pass back that we got the correct answer
resultIntent = new Intent();
resultIntent.putExtra("ANSWER",true);
setResult(1, resultIntent);
Log.d("True", "Set result has been called");
finish();
Back in MainActivity:
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data){
super.onActivityResult(requestCode,resultCode,data);
//Check which event we are responding to
Log.d("onActivityResult", "called"); //This never runs
if(resultCode == 1){
//Do something with the intent
//if q is correct, update the score in shared prefrences,
Boolean result = data.getBooleanExtra("ANSWER",false);
Log.d("ANSWER IS ", Boolean.toString(result));
qscore += result ? 1:0; //This updated score is then pushed into the next intent so it can be displayed in the next question activity.
}
}

Alright so this is your problem you start the activity for result with:
startActivityForResult(question,questionNum);
so questionNum is your requestCode
but when you finish the QuestionActivity you finish it like this:
setResult(Activity.RESULT_OK, resultIntent);
so here your request code is the value of Activity.RESULT_OK
you need them to be equal.
Edit:
for your request in the comment look at this:
private static final int REQUEST_CODE = 123131;
private Stack<Intent> intentStack = new Stack<>();
//Called when user clicks quiz
//Creates the list of questions and then asks them.
public void makeQuiz(View view) {
//Pick the questions for the quiz
question[] quiz = new question[10]; //A quiz with 10 questions
for (int i = 0; i < quiz.length; i++) {
quiz[i] = myDBHelper.pickQuestion();
askQuestion(view, quiz[i], i, qscore);
Log.d("Asked question", Integer.toString(i));
}
startActivityForResult(intentStack.pop(), REQUEST_CODE);
}
//Creates a question and then passes it though to the question view.
public boolean askQuestion(View view, question q, int questionNum, int qscore) {
question q1 = q;
Log.d("Correct Ans", q.CorrectAns);
Intent question = new Intent(this, QuestionActivity.class);
Bundle extras = new Bundle();
extras.putString("QUESTION", q.QuestionText);
extras.putString("MODULE", q.Module);
extras.putString("CORRECT_ANS", q.CorrectAns);
extras.putString("ANS1", q.WAns[0]);
extras.putString("ANS2", q.WAns[1]);
extras.putString("ANS3", q.WAns[2]);
extras.putInt("qscore", qscore);
question.putExtras(extras); //Passing the question to the QuestionActivity
intentStack.push(question);
return true;
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
//Check which event we are responding to
if (resultCode == RESULT_OK) {
//Do something with the intent
//if q is correct, update the score in shared prefrences,
Boolean result = data.getBooleanExtra("ANSWER", false);
Log.d("ANSWER IS ", Boolean.toString(result));
qscore += result ? 1 : 0;
if(!intentStack.isEmpty()){
startActivityForResult(intentStack.pop(), REQUEST_CODE);
}
}
}

Cancel/Modify Intent Message

I want to send a confirmation from the second activity to the main activity. If the checkbox is marked then I want to set Intent data and set the Result returned from activity to true.
Otherwise if the checkbox is unmarked then I want to either:
Modify the intent that was set to false
Remove the intent altogether as if it wasn't set
ConfirmCheckBox.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// Is the view now checked?
boolean checked = ((CheckBox) view).isChecked();
if (checked) {
Intent data = new Intent();
data.putExtra(EXTRA_CONFIRM, true);
setResult(RESULT_OK, data);
}
else
{
// Remove or modify to false.
}
}
});
How can I do either of the actions to modify or cancel the Intent message? also, I would like to know what's the best way to handle it?

you can remove the extras using removeExtra() method and replace it using getIntent().replaceExtras()
Remove argument from intent:
getIntent().removeExtra("search");
Replace bundle with new extras:
Bundle extras = new Bundle();
extras.putString("key","Value");
getIntent().replaceExtras(extras);

You can simply use the checkbox value as value for your Intent. There's no need to have this if/else construct.
#Override
public void onClick(View view) {
// Is the view now checked?
boolean checked = ((CheckBox) view).isChecked();
Intent data = new Intent();
data.putExtra(EXTRA_CONFIRM, true);
setResult(RESULT_OK, data);
}
In your MainActivity's onActivityResult you can simply check the Intents Extra for EXTRA_CONFIRM and decide how to react if the value is true/false.
Thats the basic approach to handle data sending between activities.
Further reading:
https://developer.android.com/training/basics/intents/result.html

How to know when Activity is finished in android?

In my android app I want to change the input method. So I start a new Activity which shows the language settings in the device. Then user can change it. However then I want to know that if the user has changed it. So I wrote a function for that also. My code so far is...
Intent enableIME = new Intent(android.provider.Settings.ACTION_INPUT_METHOD_SETTINGS);
startActivityForResult(enableIME,0);
if(isInputMethodEnabled()){
activateshadow.setBackgroundDrawable(getResources().getDrawable(R.drawable.button_pressed));
activateshadow.setText("Deactivate Shadow");
prefs.edit().putBoolean("Activate", false).commit();
}else{
Toast.makeText(MainActivity.this,"You haven't change the input method to simpleIME.In order to activate you must change it.",Toast.LENGTH_SHORT).show();
}
my is inputMethodEnabled function is....
public boolean isInputMethodEnabled() {
boolean isIME ;
String id = Settings.Secure.getString(getApplicationContext().getContentResolver(), Settings.Secure.DEFAULT_INPUT_METHOD);
String [] name = id.split("/.");
// Toast.makeText(MainActivity.this,"s:"+name[1]+":s",Toast.LENGTH_SHORT).show();
if(name[1].contains("SimpleIME") ){
isIME = true ;
}else{
isIME = false;
}
// Toast.makeText(MainActivity.this,"Returning..."+isIME,Toast.LENGTH_SHORT).show();
return isIME;
}
if(isInputMethodEnabled()) always fails because when the new intent(settings) opens and it take some time to change the input method to simpleIME . How to fix this problem?

You catch when a launched Activity returns in onActivityResult. The requestCode you supplied to startActivityForResult will be a parameter, as will the Activity's result. The Activity may also set other data which you didn't ask about.
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 555) {//555 is the intent ID you gave in startActivityForResult(enableIME,555);
if (resultCode == /*Result1*/)
//Do something
else {
//Do something else
}
}
}
You need a unique id when calling startActivityForResult(enableIME,0);
startActivityForResult(enableIME, 555);
Better still replace 555 with a named variable.

if u look at android life cycle, when activity is finished whole android call onDestroy() method.
so u can call and override this method.
just need write:
#override
protected void onDestroy(){
// code
super.onDestroy();
}
u can manage and override all of life cycle's parts in android
e.g: onResume to get current activity
i hope this help u

Android: Unable to restart an ListActivity

First post, so please go easy.
I have an app with a handful of tabs, the first is opened on running the app.
One of the tabs is 'My Account' (a ListActivity) showing account options. I switch to this and if the user is not logged in, it, in turn, runs a UserLogon activity using the following:
Intent logonActivity = new Intent(getBaseContext(), UserLogon.class);
startActivityForResult(logonActivity, 0);
To catch the result, I use the following code:
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == 0){
MainBlock ta = (MainBlock) this.getParent();
TabHost th = ta.getMyTabHost();
th.setCurrentTab(0);
finish();
}
if (requestCode == 100)
{
showAccountOptions();
}
}
In the UserLogon class, I have the usual fare; TextView's and Button's. The intention is that if the user cancels the login, it will revert to the initial tab, or if login is successful, it will show the Account Options. And this is indeed what does happen.
All good so far.
The problem I'm having is that if I cancel the login and return to the first tab, when I select the Accounts tab again, I'm not presented with the UserLogon activity. I was under the impression that finish() would close the UserLogon activity, and the Accounts activity but it would appear not.
So, my question is simply, how do I, in effect, restart the Accounts activity so that the user would be presented with the option to login once more.

We're good people and all willing to help ;-) I'll give it a shot. Still, I'm not quite sure I get that all right.
Basically you have an TabActivity which you setup and where you do something like that:
myTabHost.setOnTabChangedListener(new OnTabChangeListener(){
#Override
public void onTabChanged(String tabId) {
if (tabId.equals("account") && !loggedIn) {
Intent logonActivity = new Intent(getBaseContext(), UserLogon.class);
startActivityForResult(logonActivity, 0);
}
}});
You're basically saying that the first Activity start of UserLogon works, but the second one doesn't, right? Did you debugged to that point to check whether you reach the code which starts the activity again?
Update based on comment
Your UserLogon should always provide a result information, here's a blueprint:
public class UserLogon extends Activity {
public void onCreate(Bundle bundle) {
// ... do something ...
// if activity is canceled this will be the "last" result
setResult(RESULT_CANCELED);
}
public void checkLoginOrSomethingLikeThat() {
Intent result = new Intent();
// put your results in this intent
setResult(RESULT_OK, intent);
// close activity since we have the information we need
finish();
}
}
The parent activity which is waiting for the result should do it like that:
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// it's good practice to use a constant for 0 like LOGIN_REQUEST
// otherwise you will ask yourself later "What the hell did 0 stand for?"
if(requestCode == 0){
if (resultCode == RESULT_OK) {
// get needed data from data intent and react on that
} else {
// no success, react on that
}
}
// ... I don't know what your resultCode 100 is but handle itwith the same pattern
}

how to add button or Menu in Contacts list?

I am using following code to open Android Contacts
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btnContacts = (Button) findViewById(R.id.btn_contacts);
txtContacts = (TextView) findViewById(R.id.txt_contacts);
btnContacts.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
txtContacts.setText("");
Intent intent = new Intent(Intent.ACTION_PICK, People.CONTENT_URI);
startActivityForResult(intent, PICK_CONTACT);
}
});
}
#Override
public void onActivityResult(int reqCode, int resultCode, Intent data) {
super.onActivityResult(reqCode, resultCode, data);
switch (reqCode) {
case (PICK_CONTACT):
if (resultCode == Activity.RESULT_OK) {
//display picked contact data.
}
}
}
Now I want to put Button at the top of this Contact activity when opened or add my own Menu in this Activity
Can any one guide me? Is this possible or not? If yes then please tell how to achieve this?

I don't believe that is possible as each Activity in Android is working on its own and by starting the Intent, you are basically giving the new Activity the focus (and control).
One way to do something like this would be to build a custom contact list activity that uses the public data providers to access the contacts and simply lists them then. Then you could add as many custom functions as you like or even add Intents for original actions (like viewing a contact's details).