How to manage multiples activities under a single tab of TabActivity

Question

Hi all,

Here's the problem. In my app, I have 5 tabs which contains activities. In each of them, I have to show differents screens. For example, the main activity of a tab is a listview, and when I click on one of its item, I want to display a second screen with an other listview, that will display an other screen when the user will select an item etc.

So I knew that activities in tabs are not easy to manage, but I really think that I needed this solution. Indeed, each screen must contain a back button, which will return to the previous screen, with the previous state (the same position in the list).

To start new activities inside the tabs, I used the technique described here http://gamma-point.com/content/android-how-have-multiple-activities-under-single-tab-tabactivity

It works mostly well, but I encounter a problem to go back to the previous activities. My solution at the moment consists in starting the previous activity like it's described on this website, but without any flag.

So here are my two real problems:

• When I try to go back to the first and main activity of the tab, it seems that a new instance is created, even if I use the flag Intent.FLAG_ACTIVITY_CLEAR_TOP. So when I do several roundtrips between this activity and the next one, i obtain a StackErrorOverFlow.

• Because the activities are accessible from differents activities, I have to memorize the parents activities all the time, by giving them in the intents. It's really heavy when I have a succession of 5 or 6 screens, I have to memorize the grand grand parent if the activity... I really appreciate if I just could call the last Activity started by the localActivityManager.

Thanks for your help, and if I'm not understandable, please, let me know !

Answer 1

Ok, the solution (given on the site above), was this :

this.m_backButton.setOnClickListener(new OnClickListener() { 
  @Override 
  public void onClick(View v) {
  Intent intent = new Intent(v.getContext(), Activity1.class);
  Activity1 parentActivity = (Activity1)getParent();  
  parentActivity.replaceContentView("activity1", intent, 
                 Intent.FLAG_ACTIVITY_REORDER_TO_FRONT ); 
  }
});

and take out my main activitity from ActivityGroup. You can see the answer here : http://gamma-point.com/content/android-how-have-multiple-activities-under-single-tab-tabactivity#comment-4

Answer 2

I have still a problem with this code. I don't know how to handle the android back button. I have a graphical button to going back to the last activity with the method shown above, but if I try to add this behavior on the physical back button of the device, it doesn't work. I tried with onKeyPressent with the KEY_BACK event, but it never goes in this code section.

Moreover, with this technique of subactivites, I don't have the sliding animation when I launch a new one. I try to add the animation manually, but I may not use the good technique, because it's laggy :

public void replaceContentView(String id, Intent newIntent, int flag) {
    View view = mLocalActivityManager.startActivity(id, newIntent.addFlags(flag)).getDecorView();   

    Animation animation = AnimationUtils.loadAnimation(this, R.anim.slide_right);
    view.startAnimation(animation); 
    this.setContentView(view); 
}

Thanks

Answer 3

I had this same question I believe I have a pretty good answer with some code examples on this blog article I just wrote. multiple-android-acitivities

Let me know if it is helpful, or needs improvement.