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Change text content depending on button clicked within the same class

My problem is exactly like this link but it's not in android.
I have one button on a layout and two buttons on an another one. On my application, ClickScreen activity can be triggered by either FirstCase activity or SecondCase activity.
I tried to make a conditional statement on my ClickScreen for which activity is triggered but couldn't handle it. I don't want to create two more classes to do this since it's not an efficient technique.
private void goTo2ndPage() {
Intent i3 = new Intent(this, ClickScreen.class);
startActivity(i3);
}
public class ClickScreen extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.click_screen);
}
}

As we discussed in comments. It looks like what you really want is to add extra data in your intent so that Started Activity can get it and act accordingly.
Check out this post !

When good time to start another activity

I have an Android Best Practice question. I have to following code, which is working nicely, but I think it is not so elegant. So, my question is: at which point of activity life cycle is nice to start another activity ?
public class LoginActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ParentPreferences parentPreferences = new ParentPreferences(getApplicationContext());
if (parentPreferences.isPassExists()) {
Intent i = new Intent(this, MainActivity.class);
startActivity(i);
} else {
setContentView(R.layout.login);
}
}
}
The task is about: if the parent has already made a password to protect the app, than we don't need to show the LoginActivity. I don't know, is it "healthy" for an Activity to give an intent to launch, when nor the onCreate nor the other lifecycle methods completed.
What are you thoughts guys ?

I think the better way is to create LauncherActivity, and start activitys from them:
For example:
public class LauncherActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ParentPreferences parentPreferences = new ParentPreferences(getApplicationContext());
Intent intent;
if (parentPreferences.isPassExists()) {
intent = new Intent(this, MainActivity.class);
} else {
intent = new Intent(this, LoginActivity.class);
}
intent.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY)
startActivity(i);
}
}
Updated:
Refering to Activity | Android Developer
onCreate is a first lifecycle method, сonsequently better to start activity B when A activity just started and does not inflate any layout

I would have the manifest start your MainActivity or whatever you call it. The MainActivity starts by checking if the user has logged in. If not, it starts your LoginActivity, which comes back in onActivityResult() with the result of the login.
It does depend on the requirement for the user to log in every time they start the app, or just once, or once in a while. If the use has to log in every time, than it's ok to start with LoginActivity. Otherwise, starting LoginActivity every time and passing to MainActivity (or whatever) seems just a waste. "Waste" not in the sense of performance, but of clarity of your app.

I think the best solution for you is to add a SplashScreen or like a "fake" screen.
Here you check if he's logged in already and based on it you start the correct activity.
Maybe the absolutely best way would be to do it with fragments, but you have to change a lot of your app.
About when to call it, the onCreate is perfect :)

Pressing back button stops and destroys my Activity insted of resuming it

I' working on an app with TabGroupActivity.
I'm launching through a tabhost activies so i can have more than one Intents in each tab:
public class MainTabActivity extends TabActivity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_tab);
final TabHost tabHost = getTabHost();
tabHost.addTab(tabHost.newTabSpec("tab2")
.setIndicator("Que")
.setContent(new Intent(this, TabGroup2Activity.class)));
}
TabGroup2Activity class:
public class TabGroup2Activity extends TabGroupActivity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent i = new Intent(getApplicationContext(),QueActivity.class);
startChildActivity("categorias", i);
}
}
I got the TabGroupActivity from this page:
My issue is when i'm clicking on the second tab, i get my QueActivity.class opened. It's basically a listview with items retrieved from a Data Base. When i clic a row i get a new intent opened with information passed by Bundle object.
The problem is when i hit the back button in this intent, i go back to the QueActivity Intent, which was on onPause() event, but it goes to onStop(), onDestroy() and onStart() event insted going to other state (onResume i think) where there is no need to be created again. The issue is the Intent being created again executes SQL querys and things that i don't need to execute anymore.
I'd like to press the go back and retreive the last intent in a way i don't have to create it again.
I hope I've explained myself succesfully.

Make sure that you have closed the CURSOR off DB in your activity wherever you have used it.
stopManagingCursor(c);

Try this:
<activity ... android:launchMode="singleTop" />
In your manifest file.

This thing is device specific, some devices didnt go to onresume, and start life cycle from start, To handle that you can use Savedinstatnce, to save a state .

onResume() not called second time an Activity is launched

During the normal course of development, I noticed that a particular activity appears to have stopped responding the second time it is called.
i.e. menu->(intent)->activity->(back button)->menu->(intent)
There is nothing relevant in logcat.
I don't even know where to start debugging this nor what code to show so here are the onClick and onResume fragments:
if (!dictionary.getClassName().equals("")) {
this.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent i;
i = new Intent(mContext, NVGlobeNavigatorVC.class);
i.putExtra("PAGE_TITLE", title);
i.putExtra("TITLE", _dictionary._title);
mContext.startActivity(i);
});
} else {
findViewById(R.id.greaterthan).setVisibility(View.GONE);
}
and in the Activity being launched:
#Override
protected void onResume() {
super.onResume();
...
Nothing unusual in manifest either:
<activity
android:name=".NVViews.NVGlobeNavigatorVC"
android:theme="#style/WindowTitleBackground"
android:label="GlobeNavigator"/>
For clarity, I put breakpoints on mContext.startActivity(i) and super.onResume(). I click the view with the onClickListener and both breakpoints are hit as expected. I then press the back button which returns me to the menu. onPause() is called as expected.
I touch the view to launch the activity again, and the breakpoint on startActivity is hit but not in onResume() in the target activity. The screen goes black and the only way I can get going again is to restart the app. If I pause the debugger, it pauses in dalvik.system.NativeStart() which implies that the activity is never relaunched.
I don't think it's relevant, but I'm using Intellij IDEA and have deleted all of the output directories, invalidated the caches and done a full rebuild.
Target API is 8. I've tested on 2.3 and 4.0.4.
Any ideas? I'm stumped.
[EDIT]
In onPause, I save some stuff to prefs. The purpose of onResume() is to get them back again:
#Override
protected void onPause() {
super.onPause();
SCPrefs.setGlobeViewViewPoint(globeView.getViewPoint());
SCPrefs.setGlobeViewZoom(globeView.getZoom());
SCPrefs.setGlobeViewScale(globeView.getScale());
}

This code:
i = new Intent(mContext, NVGlobeNavigatorVC.class);
creates a new intent. The intent is of class NVGlobeNavigatorVC.class.
If you call it once, you create a new activity, lets call it "iTheFirst". If you back out of the activity, it executes "on pause". When you run the above code again, you create another new activity of the same class, but a different acitivity. Hence it won't resume your other activity, but make a new one that we could call "iTheSecond". It looks just like iTheFirst but is unique.
If you want to resume the above, after backing out of it, you need to keep a reference to it in your menu. Then in your onClick, look to see if that activity exists, and if not, make a new one and start it, and if it does exist, just resume it.
Here is a sample activity that remembers and restarts an activity:
Intent savedCueCardActivity = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState, R.layout.landing);
}
public void goToNextScreen(View v) {
if (savedCueCardActivity == null) {
savedCueCardActivity = new Intent().setClass(this, CueCardActivity.class);
startActivity(savedCueCardActivity);
// lastActivity.finish();
} else {
savedCueCardActivity.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
startActivity(savedCueCardActivity);
}
overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
}

I found the problem, and it's a bit esoteric.
I have a large static data structure which is loaded in a class static initialiser. There was a bug in that initialiser causing an infinite loop the second time it was called if the data structure was still loaded.
Because that class is referenced in my Activity, the class loader is loading it before onCreate() or onResume() is called.
The loop gave the appearance that the Activity loader had hung.

How to go back from second screen to first screen

How to switch layouts? First, I have a class Main where is onCreate (setContentView(R.layout.main);) and then I call, another class with command:
setContentView(secondClass);
In this class, I draw with Canvas and this work just fine. I also create button to go back in first "class" (R.layout.main), but I don't know how to do it.
Now my program is basic a graph shower. In first class you type your function and them second class draw it. But how to go back in first class to type another function. This "back" button or arrow witch every Android phone have, send me out of program not back on insert part.
In secondClass I can't create onCreate method, but I also tried the following and they didn't work:
Intent abc = new Intent("bla.bla.bla.FIRSTCLASS");
startActivity(abc);
and
Intent abc = new Intent(SecondClass.this,FirstClass.class);
startActivity(greNaPrvoOkno);

If you want to use a custom view (as I understood, you are extending the View class), you can do it in the following way;
Consider you are showing the second class from your Main activity like this;
setContentView(new SecondClass(getApplicationContext(), MainActivity.this));
And you Second class is this (suppose);
// I am using onClickListener to go back to main view. You do whatever you like.
public class SecondClass extends View implements OnClickListener {
// This is needed to switch back to the parent activity
private Activity mParentActivity = null;
public SecondClass(Context context, Activity parentActivity) {
super(context);
mParentActivity = parentActivity;
setOnClickListener(this);
}
#Override
public void onClick(View v) {
// Set the Main view back here.
mParentActivity.setContentView(R.layout.main);
}
}
Disclaimer: This code will do what you have asked for, but may cause other problems.
As advised by #Mudassir, you should use two different activities for two screens. It will give you better control, and your code will be easy to understand and maintain.

On the Onclick event of the button you have to write finish(); that's it..

Both of your classes are Activities yes? IF so then in your second activity you will simply call finish() and your activity will close revealing your first activity again.

When I have used multiple intents in my android application, I have created a new activity through:
Intent abc = new Intent(this, SecondClass.class);
startActivity(abc);
When the button is pressed in your second class, I would then either call finish(); on the class, or create a new intent like so:
Intent abc = new Intent(this, FirstClass.class);
startActivity(abc);
However, this method has the disadvantage that if a user wanted to use the back button, they may have to scroll through many layers of activities.

You should create another activity for your second class but not just set the main activity to a new view setContentView(secondClass).
For an easier modification, You could try to set the view back to setContentView(R.layout.main) first.
You still need to configure the widgets(e.g. TextView) on it when you set it back.
You don't have to startActivity again to go back.
Just call finish() in your second activity when you want to finish the current activity and go back:
e.g. When user press the back button in your second activity
mButtonBack.setOnClickListener(new Button.OnClickListener()
{
public void onClick(View v)
{
finish();
}
}