Develop Reference

android tablayout - how to use a button instead of tab indicators to trigger click event?

so i have a standard tabLayout that is in a viewpager.
But the very last tab needs to open a new activity. its only purpose is to open a new activity. and when the user returns from the activity by pressing the back button the last tab the user was at should be selected.
my tabs are custom views and there are 4 of them but the last one should be a button to trigger an event. so it will look just like a tab but really will be a button with a onclick listener. how can i acheive this ? i am wondering if a framelayout could be used and activated for the very last tab icon . thats the only way i can see to do it is to get the custom view and set its parent to be clickable that way it absorbs the click event. then i can set a onclick listener on the parent to open the activity. but then how to handle swipping to that tab ? swipping should open that activity as well.

Assuming you're using TabLayout.setupWithViewPager(), you can accomplish what you want by simply adding an extra tab and changing the OnTabSelectedListener.
// normal setup
tabs.setupWithViewPager(pager);
// our extra tab
tabs.addTab(tabs.newTab().setText("extra"));
// remove the `OnTabSelectedListener` created by `setupWithViewPager()`
tabs.clearOnTabSelectedListeners();
// add our own `OnTabSelectedListener`
tabs.addOnTabSelectedListener(new TabLayout.ViewPagerOnTabSelectedListener(pager) {
#Override
public void onTabSelected(TabLayout.Tab tab) {
if (tab.getPosition() == pager.getAdapter().getCount()) {
// special case for the last tab in the list
Intent intent = new Intent(MainActivity.this, OtherActivity.class);
startActivity(intent);
}
else {
// otherwise, handle as normal
super.onTabSelected(tab);
}
}
});

Android: replacing a fragment from a button click within a fragment

I took over this android project from an outsourced developer. I do iOS development so I am still trying to get up to speed with android. The app has a top tab navigation which appears on all views. The home view is a fragment which has icons which when clicked on produce webviews that replace the home view, which the navigation tab still in view. I want to replace one of the webviews with a list view which is a fragment which I already have coded (EHallSchedFragment.java), so that when the icon is clicked on the list view replaces the home view with the navigation tab still in view. See the images below.
HOME VIEW
VIEW I WANT WHEN EXHIBIT HALL SCHEDULE ICON IS CLICKED ON
Here is the code for the onClick event for that button as it exists. It calls a webView:
ivExhall.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
openInternalWebview("http://www.web.org/m/content.aspx?id=7006");
//Need code here to open EhallSchedFragment.java
}
});
SO what I need is the onClick code that will open the fragment in the existing view, leaving the navigation tab in place.

Try this approach: Define an interface inside your fragment, implement it in your activity and then override the method there. Then finally, from your fragment, when a user clicks an item from a list, call the interface method to notify the activity of the event.
From Your Fragment
#Override
public void onClick()
{
//when a user selects an event from your list
switch(position)
{
((OnScheduleSelectedListener) getActivity()).switchFragment(new DetailsFragment());
}
}
public interface OnScheduleSelectedListener
{
void switchFragment(Fragment frag);
}
You can then do the following in your activity:
public class ScheduleAppActivity extends Activity implements OnScheduleSelectedListener
{
.............................
#Override
switchFragment(Fragment frag)
{
//check if fragment is in view here and if,
replaceFragment(fragment)
//else
addFragment(frag);
commit();
}
}
So at this point, the right fragment will be added to view.
I hope this helps you!

Clicking tab not showing Home activity

I have 3 tabs in my sample application with activity group. First tab contains search activity i.e.Home/Root activity and am displaying the results of search in another activity but under same tab i.e Tab1. When I press back button in result activity, it is going to search activity. Everything works fine till here. Now I want to go search activity by pressing tab1 instead of pressing back button. How can achieve this? I tried something like this
public class TabSample extends TabActivity {
public TabHost tabHost;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.tabHost = getTabHost();
tabHost.addTab(tabHost.newTabSpec("tab1").setIndicator("OPT")
.setContent(new Intent(this, TabGroup1Activity.class)));
tabHost.addTab(tabHost.newTabSpec("tab2").setIndicator("EDIT")
.setContent(new Intent(this, TabGroup2Activity.class)));
tabHost.setCurrentTab(1);
tabHost.setOnTabChangedListener(new OnTabChangeListener() {
public void onTabChanged(String arg0) {
if (tabHost.getCurrentTabTag().equals("tab1")) {
//What should I do to display search activity here
} else {
tabHost.setCurrentTab(1);
}
}
});
tabHost.setFocusable(true);
tabHost.requestFocus();
}
}
Can anyone please help let me know how to invoke search activity when tab is pressed? What will go into if part? Because if I use tabHost.setCurrentTab(index), it will display result activity but not search activity.
NOTE: I followed the tutorial given in this link.

I think what you want to do is this: when the 'tab1' tag is selected, go back to TabGroup1Activity if (and only if) the current activity is not that activity (basically you want to simulate a 'back' press).
If so, what you want is this:
if (getCurrentActivity().getClass() != TabGroup1Activity.class)
getCurrentActivity().finish()

I'm not 100% sure I understand you fully, but let's see :)
In your onTabChanged listener you can switch on which tab have been tabed, and then open the activity as normal inside an activitygroup:
public void onTabChanged(String tabId) {
if (tabId.contentEquals("tab1")) {
Intent intent = new Intent(tabHost.getContext(), TabGroup1Activity.class);
View view = StartGroup.group.getLocalActivityManager().startActivity("tab1", intent).getDecorView();
StartGroup.group.setContentView(view);
}
}
I just reviewed my code and think there's a bit more to explain here. The problem is that you don't stack activities as normal. Instead the workaround is to make a content stack and change these instead. So what I have done is to create a class StartGroup which extends
ButtonHandlerActivityGroup:
public class StartGroup extends ButtonHandlerActivityGroup {
// Keep this in a static variable to make it accessible for all the nested activities, lets them manipulate the view
public static StartGroup group;
// Need to keep track of the history if you want the back-button to work properly,
// don't use this if your activities requires a lot of memory.
private ArrayList<View> history;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.history = new ArrayList<View>();
group = this;
// Start the root activity within the group and get its view
View view = getLocalActivityManager().startActivity("UserList", new Intent(this, UserList.class).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)).getDecorView();
replaceView(view);
}
public void back() {
if (history.size() > 0) {
// pop the last view
history.remove(history.size()-1);
setContentView(history.get(history.size()-1));
} else {
finish();
}
}
}
Then from the TabMaster class or what you call it you can use the StartGroup class to change the content view of an activity group.
This is something I wrote to work on devices from 2.2, so there might be an easier and more androidish way to accomplished it, but this works on almost all devices :)
Here is another thread where the use a similar approach:
Launching activities within a tab in Android
Let me know if I can help more.

There is an ArrayList in your ActivityGroup so override onPause() method in ActivityGroup and remove all the ids from ArrayList except the first one which must be your SearchActivity.
So when you go to other tab then comes back to SearchActivity( or on Tab1 ) Home will be displayed.

Android TabActivity Back Button Functionality with Multiple Child Activities

i have TabActivity in android project which contains some tabs. In each tab i can open various activities, and after open it in a tab i want go back to previous activity in same tab, but default android behavior close my root tab activity. How i can realise behavior that i need?

There are a few ways of doing this. The first involves creating a custom GroupActivity that will keep track of the stack from the LocalActivityManager and then extending that class for each of your tabs. For that, check out this tutorial:
http://ericharlow.blogspot.com/2010/09/experience-multiple-android-activities.html
A simpler approach is to keep an array of your tab's subviews within your initial ActivityGroup class and then override the back button. Here's some sample code:
public void replaceContentView(String id, Intent newIntent) {
View view = getLocalActivityManager()
.startActivity(id, newIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP))
.getDecorView();
viewList.add(view); // Add id to keep track of stack.
this.setContentView(view);
}
public void previousView() {
if(viewList.size() > 0) {
viewList.remove(viewList.size()-1);
if (viewList.size() > 0)
setContentView(viewList.get(viewList.size()-1));
else
initView();
}else {
finish();
}
}
The initView() class holds all of the inflating of the original activity's view. This way, you can call this method to regenerate the original activity if there are no more views in the array.

Start another Activity inside the FrameLayout of TabActivity

I am trying to make an application which have 4 tabs at the bottom of the screen.
All of them contain Activity (Intent).
And I want to navigate any of the Activity to another activity. But want to keep the TabWidget visible.
Let me know as quickly as possible if you know about it.
Shaiful

The problem of error occuring due to the replacement of activities can be solved in the following manner.
First Let us understand the flow:
We have in a Tab host , activity (say a list) from which we need to go to the next Activity (say details for the clicked item) under the same tab. For this we can use the concept of replacing the activity.Also setting the flags for the tab selected and other for knowing that details are being shown now
When we press back we should get the previous activity under the same tab.For this instead of again replacing the activity we can refresh the tab while using the particular flag for tab which was selected. Also if flag for show details is true we'll go the the list in the same tab or else we will go the activity before the tabwidget (normal use of onBackPressed)
The code can be as follows..
For going from list to details...
(This can be in the onClickListener)
private OnClickListener textListener = new OnClickListener() {
#Override
public void onClick(View v) {
Constants.SHOW_DETAILS = true;
Intent intent = new Intent(context, DetailsActivity.class);
replaceContentView("activity3", intent);
}
};
public void replaceContentView(String id, Intent newIntent) {
View view = ((ActivityGroup) context)
.getLocalActivityManager()
.startActivity(id,
newIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP))
.getDecorView();
((Activity) context).setContentView(view);
}
When back pressed is done we override on BackPressed in each of the Activity under the tab to go to the list again from the details screen
#Override
public void onBackPressed() {
// TODO Auto-generated method stub
super.onBackPressed();
if (MathHelper.SHOW_DETAILS) {
Log.e("back", "pressed accepted");
Constants.LIST_ACTIVITY = 1;
Constants.SHOW_DETAILS = false;
Intent intent = new Intent(this, Tab_widget.class);
startActivity(intent);
finish();
}
}
The most important part here is
Constants.LIST_ACTIVITY = 1; it indicates which tab we are in. so the corresponding activities will have its value as 0,1,2...etc
Again to load the correct list (Activty) when the tab activity is refreshed we have to include this in the TabWidget onCreate after the creation of the tabs
tabHost.setCurrentTab(Constants.LIST_ACTIVITY);

This is implemented in Tabs with multiple activities in a single tab.
However when multiple times activities are called StackOverFlow error arises. Tried very hard but unable to solve it.. Please someone tell a method to solve this problem
Also need to Replace an activity in a tab, However from child activity. How is that to be done?

At any one moment there may only be one activity. Docs about this here