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android back navigation on child method?

im creating redirect to some view on object method. this method doesn't use the parent view.
it works but when i click back navigation it doesn't showing the previous page (previous page is object oncreate() method itself), it return to the top parent activity. here is my code :
Object method on create :
public class FormDatabase extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.form_database);
method member of object method :
public void showArrayResult(View view)
{
setContentView(R.layout.profile_listview);
how can when i click back navigation i would return to previous object onCreate() method NOT the parent method (MAIN_ACTIVITY).
Hope my description is clear enough. Thanks.

To switch between different views in the same activity, and still maintain the ability to use the back stack (back button), you should probably use Fragments.
If the two views are completely independent then you should consider moving it into its own separate Activity.

You can override the onBackPressed() callback method to interrupt killing the activity and instead SetContentView as you did in onCreate()
EDIT
But Nic is right about moving to a fragment or another activity.
A component such as an activity should manage one task. Otherwise it is considered as bad practice.

Android: How to restart activity?

I made 2 activities.
e.g] MainActivy and MediaActivity.
If user click home button in MediaActivity, App will hide.
I want launch MediaActivty again when screen on.

Open the gmail app, tap on an email to show it's contents. You have now gone from one activity (email list) to another (email details). Press the home button. Now open the gmail app again. Voila! You have returned to the email you selected.
What you ask for is the default behavior of an Android app. Unless you do something like call finish() in your onPause() method in MediaActivity you should return to MediaActivity when you open the app again.
If your app doesn't behave like this I suggest that you post some code.

Try to write your activities the following way :
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Put your own code here.
}
}
public class MediaActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Put your own code here.
}
}

What you're asking is Up Navigation / Ancestral Navigation(if I understood it correct). Refer to this guide: http://developer.android.com/training/implementing-navigation/ancestral.html
Othewise, if you want to have multiple instances of an activity, it's android:launchMode property should be set to standard in manifest. Refer:
http://developer.android.com/guide/topics/manifest/activity-element.html

onCreate not called

I have 2 Activities : First activity user clicks on a button which launches the 2nd activity. The 2nd Activity does all the work.
I launch the 2nd Activity as follows which is inside a onClickListener Inner Class and I have tried explicitly calling it with (FirstActivity.this,Simple.Class) but same thing happens.
Intent test = new Intent(arg0.getContext(),Simple.class);
startActivity(test);
On the emulator, I see the screen move over like its calling the 2nd activity but all I get is a black screen but nothing is loaded from my layout. I looked at logcat and I do see some binder thread failed messages. This is the onCreate function from my 2nd activity but I do not get any results from either the screen or logcat showing me that the Log functions were called:
public void onCreate(Bundle savedState)
{
Log.d("SimpleActivity","OnCreate Started");
super.onCreate(savedState);
setContentView(R.layout.simple);
Log.d("SimpleActivity","OnCreate Ended");
}
Note : I have called the base constructor in OnCreate() with super.onCreate(savedState) in my code above.

What happened to me was I was overriding the wrong onCreate method. I was overriding public void onCreate(Bundle savedInstanceState, PersistableBundle persistentState) when I really needed to override protected void onCreate(#Nullable Bundle savedInstanceState). Maybe this might help someone!

It's possible that onCreate doesn't get called, if the activity has never been destroyed,
if for some reason an activity hangs around, next time its instantiated it is not recreated but resumed instead...
At least that's what im Dealing with right now in my code... Life cycle of Activities seem a good logical explanation.. However 99% of time I do rely on onCreate being called when startingActivity and it doesn't fail me....
Edit: And of course its because I wasn't calling finish() when exiting the activity. Doh.

This is not related to this certain issue, but also this can happen when activity is not declared in manifest file)

Be careful that if your method belongs to AppCompatActivity or Activity .
It is up to what you implemented to your Class
If you want to add lifecycle or any override methods, I recommend you to press
CTRL+O or do Code > Override methodsand there you can see where the method belongs

remove android:launchMode="singleTask" from manifest

you should #Override onCreate and add super.onCreate() in it
#Override
public void onCreate(Bundle savedState)
{
super.onCreate(savedState);
Log.d("SimpleActivity","OnCreate Started");
setContentView(R.layout.simple);
Log.d("SimpleActivity","OnCreate Ended");
}

my case
(1) mainActivity -> (2) open Adaptor - startActivity -> (3) mainActivity onCreate() doesn't get to triggered.
I resolved this by adding finish();. in mainActivity.
follow the below steps to check your application.
1.did you override the right method? if not overriding the below method, this method will be triggered, when you startActivity.
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
2.Make sure that you registered the activity in manifest.xml
2.1 is your activity has android:launchMode="singleInstance" ?
(if your application doesn't need to be singleinstance, consider to remove.
but my case I need singleinstance. hence i moved to the next step)
use finish()
public void openSearch(View view) {
Intent intent = new Intent(this, BookInfoActivity.class);
intent.putExtra(...);
startActivity(intent);
finish(); // add like this.}
why do we need to use "finish()"?
Screen A -> click button on A -> Screen B -> click button on B -> screen A with some new data that you get from Screen B
if you don't call finish() method(in A button) , that means the A is still in your background
even you are seeing the screen B.
hence, when you trigger startActivity on screen B, it just simply shows the running A screen.
however if you use finish() method (in A button), when you go to B Screen,
it destroys the A screen, so when you go back to A screen by clicking B method( 'StartActivity') it creates A screen and trigger onCreate() Method .

You need to call the super.onCreate(savedState) method. Take a look at Activity doc.
public void onCreate(Bundle savedState)
{
super.onCreate(savedState);
}

How do I create common code for parts of Android activities?

In my application there are 14 activities. Out of that 9 activity contains custom title bar and tab pane. so here I need to write this common code at one place instead of redundant code in each activity that contain custom title bar and tab pane code (i.e layout and it's activity specific code)
What are the possible ways to do this?

The common way is:
Create a super class called, for instance, CommonActivity which extends Activity
Put the boilerplate code inside that class
Then make your activities extend CommonActivity instead of Activity:
Here a simple example:
public class CommonActivity extends Activity{
public void onCreate(Bundle b){
super.onCreate(b);
// code that is repeated
}
protected void moreRepeatitiveCode(){
}
}
And your current activities:
public class AnActivity extends CommonActivity{
public void onCreate(Bundle b){
super.onCreate(b);
// specific code
}
}

Hmm.. Common code doesn't always need to be in Activity class but just regular class. Than we could call those methods according to our needs referring to the common code class.
Am I right with this example?
Of course in case we need it like Activity, above proposal would work perfectly if we take care of Activity lifecycle and we don't forget to add it to manifest file.
In general Activities should just create UI, handle events occurrences and delegate business logic and/or other actions to the other components in our App.
Cheers

Going Home Screen of app in android?

I want to go to homePage of my application on clicking button where i was in inner page.
Can any one tell me how to do that ?
Thanking you ,
Srinivas

I suggest creating an Application class. In that class have a boolean field that is false by default. Every Activity should check if that field is true in onResume() and call finish() if it is true (except for the main activity that always sets the field to false in onResume()). You can even create a custom Activity that does this and then have all activities extend that activity.
Resources:
http://d.android.com/resources/faq/framework.html#3
The android.app.Application class
The android.app.Application is a base class for those who need to maintain global application state. It can be accessed via getApplication() from any Activity or Service. It has a couple of life-cycle methods and will be instantiated by Android automatically if your register it in AndroidManifest.xml.
Reference: http://d.android.com/reference/android/app/Application.html
Stripped-down example:
MyApp
public class MyApp extends Application { public boolean goBack = false; }
MyActivity
public class MyActivity extends Activity {
protected void onResume() {
if ( ((MyApp) getApplication()).goBack ) finish();
}
}
SomeActivity
public class SomeActivity extends MyActivity {
// nothing special here, it's all been implemented in MyActivity!
}
MainActivity
public class MainActivity extends Activity {
protected void onResume() {
((MyApp) getApplication()).goBack = false;
}
}
AndroidManifest.xml
[...] <application android:name=".MyApp" [...]> [...]
Note: You don't need to declare MyActivity in AndroidManifest.xml because it will never be launched directly (it will only be extended).

On your button click event add the following lines of code
moveTaskToBack(true);

There are probably two ways of doing that (general concepts):
The first one would be to simply launch the home actvity again, if you don't mind having it re-created again, unless that activity is a "singleTask" or "singleInstance" activity.
The second one would be to close the top activity in the stack as long as it is not your home activity. I don't see an easy way to achieve that, maybe by finishing the current activity with a specific result that gets checked by the launching activity, who will in turn close and send the result until the home activity is reached.