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How to implement a succession of activities within a single tab of a tabhost?

I have implemented a TabHost. In one tab I have Activity1, which calls Activity2 after a button click, which calls Activity3 after a button click, which calls Activity1 after a button click, etc.. No backstack functionality is required, just 1 --> 2 --> 3 --> 1, etc. All three activities have a separate layout file.
Everything works fine, except that after the first transition from 1 --> 2 the activities grab the entire screen and the tabs are invisble forever.
Question: how can I keep these three activities within the confinement of de tab area and the tabs visible? The problem has been recognized here many times before; the solution used to be ActivityGroups, but these are deprecated and Fragments are advised instead. I have seen many examples here, but nothing that could help me.
Can I keep my three activites (Activity1 extends Activity, etc)?
Should I add fragment tags to the layout files?
Do I need to work with transactions?
Should I work with one fragment class or three?
Can you please give me a few hints how I should go about? I woud already be helped if you tell which classes I need to use and of what type they are.
Thanks in advance.

It took me more than half a day, but finally found a solution that works. Unfortunately I am still stuck with deprecated issues (Activity Group and getLocalActivityManager().startActivity(..)).
Again I have a single tab under a TabHost and several activities, all operating within that tab. Navigation from one activity to the next occurs with a buttonclick. Solution:
all Activities operating within the tab need to extend ActivityGroup
All Activity classes need to have a button handler that links to the next activity like this:
public void onBtnClicked(View view) {
Intent intent = new Intent(view.getContext(), NextActivity.class);
replaceContentView("NextActivity", intent);
}
public void replaceContentView(String id, Intent newIntent) {
View view = getLocalActivityManager().startActivity(id, newIntent.
addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)).getDecorView();
this.setContentView(view);
}
By this the tabs remain visible all the time, as desired.
Hope this helps someone.

Remove of switching activity animation on Android

There are two activities.
Activity A has a button that can switch to Activity B.
Activity B also has a button that can switch to Activity A.
here is my code,
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
Log.e("current", context.getClass().toString());
Log.e("changeto", tab.getTag().toString());
if(context.getClass()==tab.getTag())
return;
Intent intent = new Intent(new Intent(context,(Class<?>) tab.getTag()));
intent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
context.startActivity(intent);
}
I want to remove the animation when i switch the activities, but it doesn't work.
However if I remove
intent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
it works perfectly. Why?
Sorry for my bad English.

In the Activity that you're switching to, try using overridePendingTransition(0,0); either in onResume or in onCreate.

If you're calling startActivity in a tab switch, you're doing it wrong. Tabs are for switching views within the current activity, and switching tabs should never create navigation history. Consider switching a fragment or replacing your view hierarchy with the newly selected tab's content instead.
The more you pursue a path of switching activities for tab selection, the more you will find yourself playing whack-a-mole with subtle user experience bugs that make your app simply feel "wrong."
With your proposed implementation above, the Back button will return to the previously selected tab, breaking the, "never creates navigation history" rule. You may think that finish()ing the current Activity as you start the next can solve this, but you'll still have a host of other issues. Users expect subtle elements of state such as scroll position to persist across tabs. As of Android 4.0 there is an expectation that users should be able to swipe horizontally between tabs (http://developer.android.com/design/building-blocks/tabs.html) which you will not be able to accomplish if you are using separate activities for each tab's content.
This is only a small sample, the list just goes on. Tabs should not be used to switch between different Activities.

Android - display a persistent view over all activities

I'd like to recreate a functionality similar to a Swing GlassPane to be able to display animations while the user uses the app "below" normally. I cannot simply create a separate layout and attach it to each activity since the animation state would be lost when switching activities.
Is there a way to keep a persistent view over all the activities of an Android application ?
Thanks.

No its not. Every Activity runs in its own thread and is by design supposed to be runnable standalone.
But you could persist the animation state into the DB or into sharedPreferences and start it over at the new activity.
What you could also do is to use a Spinner or another control instead of seperate activitys. Then you could have a persistent view.

why not think in a TabActivity?
hi! i do this before with a TabActivity, never with an only activity, always with many activitys wich i started, get theirs windows and setting as my TabActivity window´s decor view... i dont tested the code below, since is an idea, but maybe more lately (when i'll be on home) i'll write an example...
So, my idea...
a TabActivity is composed by a TabWidget and a FrameLayout where the activity´s windows is allocated.
the TabWidget can be any view, so, you can put the animated view here.
the most difficult thing is the fact that, if you start an activity from the TabActivity´s child, then the new activity will be on top of the TabActivity. In order to overrides this behavior the TabActivity must know when a nested activity wants to start another activity. When this happens the TabActivity must clear his decor view (with the old window activity) and put the decor view of new one. Something like this:
on the child activity, launch a new activity when we click on a button:
... on click listener...
((MyTabActivity)getParent()).createNewActivity("NewActivity", NewActivity.class);
now, we´re saying the TabActivity that it has to start a new activity, get the new activity decor view and put that view inside the TabActivity decor view... so, the createNewActivity will perform something like this:
public void createNewActivity(String activityId, Class<?> class1) {
Intent intent = new Intent( getIntent().getAction() ).setClass(MyTabActivity.this, class1);
Window wList = getLocalActivityManager().startActivity(activityId, intent);
getWindow().setContentView(wList.getDecorView());
}
hope you understand me.
i'll write an example later

Android tabs event

I stuck with one problem. actually my screen consists of two tabs. under each tab i have 4-4 activity. i m displaying each activity with the help of activity group in single tab.
Suppose i m in 1st tab which is active. Under this tab i m on 2nd activity(e.g first activity is list activity and second activity gives the result from the first activity)
I want when i click on 1st tab again it should show me the first activity again without using back button.?

I had that problem sometime ago... and that happens because people like to emulate the bottom bar of the iPhone. Android apps don't work that way and using Activity Group is always a signal of a poor UI design.
Anyway, this is what I did:
tabHost.setCurrentTabByTag(TAB_ID_MORE);
tabHost.getCurrentTabView().setOnClickListener(new OnClickListener() {
public void onClick(View v) {
if( MoreGroupActivity.self != null ) {
MoreGroupActivity.self.reset();
}
tabHost.setCurrentTabByTag(TAB_ID_MORE);
}
});
tabHost.setCurrentTabByTag(TAB_ID_HOME);
The above code is not generic, but will give you an idea of the workaround I found. Let me explain:
tabHost.setCurrentTabByTag(TAB_ID_MORE); I use this to select a current tab (in my case, the main tab was another tab, so I had to to this and then change back with tabHost.setCurrentTabByTag(TAB_ID_HOME);). I mean, in my case, the only tab with that behavior was the "More" tab.
tabHost.getCurrentTabView().setOnClickListener this allows you to put a listener to the tab. As you may have already noticed, using OnChangeTabListener is not an option in this kind of situation.
MoreGroupActivity.self Inside my group activity, I had a static field referencing the group activity it self. This kind of hacks are common while using this crappy approach.
tabHost.setCurrentTabByTag(TAB_ID_MORE); this reset the tab so that it can change back to your first activity.

When you are adding a new TabHost.TabSpec to the TabHost
use
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP| Intent.FLAG_ACTIVITY_SINGLE_TOP);
to the respective Intent

Android:How to change opened tab dynamically

I have an Android application which has four tabs (I use a main TabActivity with TabHost and TabSpecs).
In one of my sub activity (activity opened in a tab), i need to open a tab not by clicking on the tab title and i don't know how to do this.
For example, i have a button in my activity and when i click on it, it opens a different tab.
For the moment, it is what i do:
Intent intent = new Intent(myActivity.this, myTabActivity.class);
intent.putExtra("ComeFrom", true);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
Then in the TabActivity, if i get true reading the "ComeFrom" extra i open the wished tab but the problem is that it kills all the other activies. So, if someone knows a better (cleaner) way to do that trick, please tell me...

Found an easier (I think) answer:
on the TabActivity declare a public, static and self variable and populate it on the onCreate method. F.e.:
public class TheActivity extends TabActivity {
public static TheActivity self;
...
#Override
public void onCreate(Bundle savedInstanceState) {
self=this;
on any Activity running in a tab, when you want to change the one shown on your app. you can do this:
TabHost tabHost = TheActivity.self.getTabHost();
tabHost.setCurrentTab(0);
Worked ok for me, hope serves someone else!

You have to use TabHost's "setCurrentTab(...)" for that. In one of my projects, I created a static method in the main Activity (the one with the TabHost), named "swtichToTab(int tab)". In my subactivites (those inside the tabs) could then just call "MainActivity.switchToTab()" to trigger switching.
It may not be the cleanest method, I'm sure you can achieve this using broadcast intents too.

You can create a BroadcastReceiver and send a broadcast with the index of the tab as extra

You can use views instead of activities for the content of the tabs. This way, the code is simpler and doesn't use as much memory. Plus, you then can use the setCurrentTab(tabIndex) method to easily switch between views.
I have a simple tutorial here. It has a tab activity with a list and map view. When you you click on an item in the list, the activity dynamically goes to the map view (using the setCurrentTab(tabIndex) method). You can easily modify this to have a button switch views.