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Android skip Activity and put it last

I am trying to make a skip button and it have to do what i draw.
i honestly don't know how can i make this happen.
The code actually have to skip the current activity and put it as last.
if the activity's question was answered, there is no skip.here i draw
I have tried a few things but it's beyond my powers.
Intent intent=new Intent(this, c1_2.class);
startActivity(intent);
finish();

you can use arrayList or Queue for keep your activityes, then use it to start Activity.
try this.
final ArrayList<Class> activities = new ArrayList<>();
// add your activity---------------
activities.add(c1_1.class);
activities.add(c1_2.class);
activities.add(c1_3.class);
//----------------------------
butonSkip=findViewById(R.id.skip);
butonSkip.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Class firstActivity = activities.get(0);
startActivity(new Intent(c1_1.this,activities.get(0)));
activities.remove(0);
activities.add(firstActivity);
}
});
//-----------can change activities data
// activities.set(1, c1_3.class);

Returning string from Android Activity started with `startActivityForResult` inside `onClickListener` returns null

I use an Intent in MainActivity to start another Activity called MatchesActivity using startActivityForResult. I put breakpoints at finish() inside the started activity (MatchesActivity) and on the Log statement inside onActivityResult because I got NPE inside onActivityResult.
intent.getStringExtra("TXAMATCHES") contains what it should.
But Intent data comes back null.
Is this likely/possibly because I start the Intent inside an onClick listener?
Or because MatchesActivity calls a method in another class that extends AsyncTask and the data is what that task produces? (But the correct data is found in txaMatches just before it is returned to MainActivity...)
public class MainActivity extends Activity
{
...
btnSearch.setOnClickListener(new View.OnClickListener() {
#Override public void onClick(View v)
{
...
Intent matchesIntent;
matchesIntent = new Intent(MainActivity.this, MatchesActivity.class);
startActivityForResult(matchesIntent, 0);
...
}
...
#Override protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
Log.w("MainActivity","" + onActivityResult " + data.getStringExtra("TXAMATCHES"));
}
}
...
public class MatchesActivity extends Activity implements DatabaseConnector.DatabaseProcessListener
{
...
#Override protected void onDestroy()
{
super.onDestroy();
finishThisAndReturnString();
}
public void finishThisAndReturnString()
{
Intent intent = new Intent();
intent.putExtra("TXAMATCHES",txaMatches.getText().toString());
setResult(RESULT_OK, intent);
finish();
}
(The started Activity is terminated by user pressing back icon.)

You can't finish a activity in the onDestroy method. In this lifecycle phase the activity is already dying.
The call of the finish() method will call the onDestroy, not the other.
Call the finish method when you want to to finish the MatchesActivity.

What you're trying to do is not correct. You're trying to call finish() on the onDestroy() method. onDestroy() gets called when the Activity is about to be killed. So basically calling finish() at that point is wrong.
I assume that you are trying to do some processing in the AsyncTask. I suggest that you call the finish() method on the onPostExecute() method of the AsyncTask.

You are setting the data in the Intent object in onDestroy() method . So in this case, whenever you call setResult() in onDestroy() method, you will always get resultCode in onActivityResult() as '0' which is the value for RESULT_CANCELED and whenever you get RESULT_CANCELED in onActivityResult() you get data object null. That's why you don't get the values you set in Intent .

First try to get the value of
txaMatches.getText().toString()
Check this value in the MatchesActivity Class.
It is possible that it is returning null value due to which u are getting the problem.

The problem is fixed by removing finishThisAndReturnString() from onDestroy, as stated in the first two Answers.

Placement of OnActivityResult with OnClicklistener

I have implemented a 3rd party camera scanning app within a project of mine
I have an adaptor that extends a viewholder so i can have a custom layout
Within a view i have a button
When i create the view i add an OnclickListener to the image which i want to make clickable
i want this OnclickListener to call the camera but i need to call an startActivityForResult
i am confused about the placement of the onActivityResult when calling in this way.
my current attempts have been to create a seperate class(scan_activity) which extends activity but i couldnt get the onclicklistener to start the class
i have then attempted to declare it within the setOnClickListener, which as you can guess also failed.
Im guessing the call to the class is the way forward.im sure its an easy fix, but im not seeing it
please help
thanks in advance
imgCamera.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(context, ScanActivity.class);
intent.putExtra(ScanConstants.OPEN_INTENT_PREFERENCE, 1);
((Activity) context).startActivityForResult(intent,99);
}
}
);
and the class
imgCamera.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
new ScanActivity
}
}
);

The first option should work. You create an Intent object and you specify activity component as a parameter. Android will create an Activity object for you, so, never do that manually. Android should manage the lifecycle of activity.
By starting activity for result you tell Android that it should call onActivityResult callback with request code 99 on your first activity when ScanActivity will be closed.
Handling onActivityResult in your Activity:
#Override
public void onActivityResult (int requestCode, int resultCode, Intent data) {
if (requestCode == 99) {
// handle your result here
}
}

Making an activity which started itself go back to previous screen with "onBackPressed()"

I have an activity which is repeated "x" times with this piece of code :
//create intent to start itself again with different parameters
Intent intent = getIntent();
intent.putExtra(CATEGORY_ID, temp.getCat_ID());
intent.putExtra(CATEGORY_SHOPID, temp.getShopID());
intent.putExtra(CATEGORY_SITEID, temp.getSiteID());
intent.putExtra(CATEGORY_NAME, temp.getCat_Name());
finish();
startActivity(intent);
My goal is that when the user presses the back button that the same activity gets started as there was before with the same parameters as before and such. I tried saving them in an Activity ArrayList but that doesn't seem to work.

When you call finish, your activity will end.
When you don't call finish, your activity just go to the background. In that case, when you press the backbutton in your new activity, your previous activity comes up.
I think when you just delete finish(), it will work.

It's okay if you save the parameters you've already set earlier, but you need to retrieve all that information from the Intent itself and repopulate your activity with the proper data.
This must be done like this:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String categoryId = getIntent().getStringExtra(CATEGORY_ID);
// retrieve the others and populate your activity
}

in your activity, get event back
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK ) {
// and you have to make a intent to call this activity again with parameter other
finish(); // and call finish() here to close the old activity
}
return super.onKeyDown(keyCode, event);
}
hope this help!

Have you tried overriding the onBackPressed method?

Do I need to include a default Intent in order to return to the previous Activity?

I am working on a To Do List Android application (it happens to be for a class assignment, but that's not what I'm asking about--I've tried to leave out as much code as I could). The main screen displays a list of ToDo items with a button at the bottom to open the Add New ToDo Item screen.
On the Add New ToDo Item screen, there is a Cancel button.
Relevant ToDoManagerActivity.java snippet:
public void onCreate(Bundle savedInstanceState) {
// Init and setup adapter, etc.
footerView.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(ToDoManagerActivity.this, AddToDoActivity.class);
startActivityForResult(intent, ADD_TODO_ITEM_REQUEST);
}
});
// Attach the adapter to this ListActivity's ListView
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
log("Entered onActivityResult()");
// Check result code and request code.
// If user submitted a new ToDoItem
// Create a new ToDoItem from the data Intent
// and then add it to the adapter
}
Relevant AddToDoActivity.java snippet:
protected void onCreate(Bundle savedInstanceState) {
// Initialize default view, handle other events, etc.
final Button cancelButton = (Button) findViewById(R.id.cancelButton);
cancelButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
setResult(RESULT_CANCELED, new Intent());
finish();
}
});
}
The above code works. Previously, I was trying this in the onClick handler for cancelButton:
public void onClick(View v) {
finishActivity(RESULT_CANCELED);
}
When I clicked the Cancel button, I could see that the onActivityResult was being reached in the logs, but the screen was not reverting back to the main ToDo list screen.
Why does the above code not return me to the previous screen, but the following code does return me to the previous screen? What am I misunderstanding about the task backstack/activities?
public void onClick(View v) {
setResult(RESULT_CANCELED, new Intent());
finish();
}

According to the documentation:
public void finish ()
Call this when your activity is done and should be closed. The ActivityResult is propagated back to whoever launched you via
onActivityResult().
and
public void finishActivity (int requestCode)
Force finish another activity that you had previously started with startActivityForResult(Intent, int).
You should call finish() to close the current activity and finishActivity() to close another activity you started using startActivityForResult(Intent intent, int requestCode). Calling finishActivity() on the current activity will not close it.
Also, there's no point in creating a new Intent for setResult() as you are not passing back any data. Doing this would be sufficient:
setResult(RESULT_CANCELED);
finish();

From Android Docs:
public void finishActivity (int requestCode)
Force finish another activity that you had previously started with startActivityForResult(Intent, int).
finishActivity does not finish the current activity but calls finish for an activity called with requestCode

If you look at the documentation for finishActivity() it says that it will force finish an activity started with startActivityForResult(), but you have to pass in the request code that you used to start the other activity. In your case it would be ADD_TODO_ITEM_REQUEST.
This is probably not the API you want to use. Your 2nd method is cleaner in that you don't need to force close the child activity, but let it finish in the normal way.