I am using ActionBarSherlock's action bar tabs in my application with each tab populated by a single fragment inside a SherlockActivity Tabs.
One of my Tabs contains a fragment, FragmentHome, with a list of news articles. When an article is selected, FragmentHome is replaced by another fragment, FragmentNews.
FragmentNews just contains a webview to load the selected article. The article is loaded fine. I override the onBackPressed in my activity so that FragmentHome is reattached and FragmentNews is removed.
While there are no errors, the webview inside FragmentHome is never removed from the view and overlaps with other fragments. (See screenshots)
Its weird because the same code works for a another SherlockFragment with ListView in it but is messed up when using a WebView. Here is the code to replace FragmentHome with FragmentNews initially:
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
listNews.setItemChecked(position, true);
Bundle bundle = new Bundle();
bundle.putStringArray("NEWS",
new String[] {
mNews.newsFeed.get(position).getTitle(),
mNews.newsFeed.get(position).getLink()
.toExternalForm() });
FragmentTransaction ft = getSherlockActivity()
.getSupportFragmentManager().beginTransaction();
Fragment frag = SherlockFragment.instantiate(getSherlockActivity(),
FragmentNews.class.getName(), bundle);
ft.detach(getSherlockActivity().getSupportFragmentManager()
.findFragmentById(getId()));
ft.add(android.R.id.content, frag, Tabs.FRAG_NEWS);
ft.commit();
}
Overriden onBackPressed in Tabs:
#Override
public void onBackPressed() {
Fragment frag = getSupportFragmentManager().findFragmentByTag(
FRAG_DETAILS);
if (frag != null && frag.isVisible()) {
FragmentTransaction ft = getSupportFragmentManager()
.beginTransaction();
ft.remove(frag);
Fragment mFragment = getSupportFragmentManager().findFragmentByTag(
TAB_PORTFOLIO);
if (mFragment == null) {
mFragment = SherlockFragment.instantiate(this,
FragmentPortfolioList.class.getName(), null);
ft.add(android.R.id.content, mFragment, TAB_PORTFOLIO);
} else {
ft.attach(mFragment);
}
ft.commit();
} else {
frag = getSupportFragmentManager().findFragmentByTag(FRAG_NEWS);
if (frag != null && !frag.isDetached()) {
Log.e("onBackPressed", "for " + frag.getTag());
FragmentTransaction ft = getSupportFragmentManager()
.beginTransaction();
ft.remove(frag);
Fragment mFragment = getSupportFragmentManager()
.findFragmentByTag(TAB_HOME);
if (mFragment == null) {
mFragment = SherlockFragment.instantiate(this,
FragmentHome.class.getName(), null);
ft.add(android.R.id.content, mFragment, TAB_HOME);
} else {
ft.attach(mFragment);
}
ft.commit();
} else {
Log.e("onBackPressed", "inside else");
super.onBackPressed();
}
}
}
Snippet from FragmentNews
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
arr = getArguments().getStringArray("NEWS");
setRetainInstance(true);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_news, container);
newsView = (WebView) view.findViewById(R.id.news_WV_Brief);
newsView.getSettings()
.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
newsView.getSettings().setGeolocationEnabled(false);
newsView.getSettings().setAllowFileAccess(false);
newsView.setWebViewClient(new WebViewClient() {
#Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
Log.e("override", url);
return true;
}
});
return super.onCreateView(inflater, container, savedInstanceState);
}
#Override
public void onResume() {
super.onResume();
newsView.loadUrl(arr[1]);
}
I have seen posts talking about FlashPlayer causing issues because of SurfaceView cutting a hole but I am just displaying simple webpages without any videos. Help highly appreciated.
I figured out the problem while going over the source code of WebViewFragment. I realized there isn't much going on other than pause/resume of webview.
I had two serious errors in my code:
I never returned the inflated view in onCreatView in
FragmentNews. I was returning super.onCreateView(inflater,
container, savedInstanceState).
I forgot to set attachToRoot to false in onCreateView when
inflating the XML layout - View view =
inflater.inflate(R.layout.fragment_news, container, **false**)
Therefore, the inflated view was just standing on its own without being attached to the fragment. When the fragment was replaced, it resulted in a mashed up display because the inflated layout containing the WebView was never removed. Unfortunately, this complied without errors.
Related
This question already has answers here:
Start a fragment via Intent within a Fragment
(5 answers)
Closed 6 years ago.
i want to replace activity to a fragment, this code is not working.
Intent intent = new Intent(Activity.this, Fragment.class);
startActivity(intent);
finish();
You cannot switch from an Activity to Fragment, because a Fragment does not have its own existence without an Activity. i.e. a Fragment works inside an Activity.
Basically, Fragments are mainly used to create multi-pane screens.
Inside an Activity if you can replace Fragments (associated with the Activity) as mentioned in the above code examples to change the UI.
Try like this in your activity
#Override
public void replaceFragment(Fragment fragment, boolean addToBackStack) {
FragmentTransaction transaction = getSupportFragmentManager()
.beginTransaction();
if (addToBackStack) {
transaction.addToBackStack(null);
} else {
getSupportFragmentManager().popBackStack(null,
FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
transaction.replace(R.id.flContent, fragment);
transaction.commitAllowingStateLoss();
getSupportFragmentManager().executePendingTransactions();
}
and use like this
YourFragment mYourFrag = new YourFragment ();
replaceFragment(mYourFrag , false);
Create a Fragmen class like
public class FragmentName extends android.support.v4.app.Fragment {}
And then you are able to cast a activity to view like:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View returner = null;
Intent intent = new Intent([CONTEXT],[CLASSNAME.class]);
Bundle args = this.getArguments();
final Window w = [LocalActivityManager].startActivity("Title", intent);
final View wd = w != null ? w.getDecorView() : null;
if (wd != null) {
ViewParent parent = wd.getParent();
if(parent != null) {
ViewGroup v = (ViewGroup)parent;
v.removeView(wd);
}
wd.setVisibility(View.VISIBLE);
wd.setFocusableInTouchMode(true);
if(wd instanceof ViewGroup) {
((ViewGroup) wd).setDescendantFocusability(ViewGroup.FOCUS_AFTER_DESCENDANTS);
}
}
returner = wd;
return returner;
}
I'am trying to make a app with a flexible UI.
I already implemented for handset devices (I have one activity and multiple fragments), and what I done was: The main fragment is a dashboard, and when I click in one button of it, he dashboard is replaced by a new fragment ( the clicked feature). Here is the code:
Dashboard fragment:
public class DashboardFragment extends Fragment {
GridView gridView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
return inflater.inflate(R.layout.activity_dashboard, container, false);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
gridView=(GridView)getView().findViewById(R.id.dashboard_grid);
gridView.setAdapter(new ImageAdapter(getActivity()));
gridView.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
FragmentTransaction transaction = getFragmentManager().beginTransaction();
Fragment fragment = null ;
switch (position) {
case 0:
fragment = new TestFragment();
break;
case 1 :
fragment = new TestFragment();
break;
case 2 :
fragment = new TestFragment();
break;
case 3 :
fragment = new TestFragment();
break;
case 4 :
fragment = new TestFragment();
break;
}
transaction.replace(R.id.container, fragment);
transaction.addToBackStack(null);
transaction.commit();
}
});
}
}
and my Main Activity:
public class MainActivity extends FragmentActivity{
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (findViewById(R.id.container) != null) {
if (savedInstanceState != null) {
return;
}
// Create an instance of ExampleFragment
DashboardFragment firstFragment = new DashboardFragment();
firstFragment.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction().add(R.id.container, firstFragment).commit();
}
}
}
Now, what I want is to adapt this code and use a layout for tablets, with the dashboard on the left and the choosen fragment on the right, like this:
What could I do? I already tried to adapt this example, but I can't because they only update the fragment, they don't replace it.
Check this great article about multi-pane development.
It also includes an example (Sections 10 and 11)
Basically you can check whether there is a fragment element for your "Fragment B" in the current layout. If yes, you just update its content, if no, then start an activity which has it in its layout, or replace one in the current layout.
DetailFragment fragment = (DetailFragment) getFragmentManager().findFragmentById(R.id.detail_frag);
if (fragment==null || ! fragment.isInLayout()) {
// start new Activity or replace
}
else {
fragment.update(...);
}
I am using the following code to populate my UI with 2 fragments, the containers are FrameLayout's defined in XML. This first time this code is called i.e. when the app starts, it works fine, and both my fragments are displayed as expected. However after a configuration change(specifically, orientation), only the first fragment in the transaction is shown.
I don't think it's an issue with the fragments themselves, because if I reverse the code so one replace is called before the other or vice versa, that fragment will be displayed. So for example with the snippet from below as a guide, if I swap the mSummary and mDetails replace calls, then mDetails will be displayed and mSummary won't.
It's always the second one in the block that is missing.
// Using tablet layout
} else {
FragmentManager fm = super.getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.summary_container, mSummaryFragment);
ft.replace(R.id.details_container, mDetailsFragment);
ft.commit();
}
I'm saving the fragments in onSaveInstanceState and restoring them from the Bundle savedInstanceState when the activity is recreated. I also tried breaking the transaction into two pieces by calling commit() and then getting another FragmentTransaction object but no joy there.
So for anyone coming across this at a later stage...
I finally manage to fix this by creating a new instance of the fragment and restoring it's state using a Fragment.SavedState object. So:
if (mSummaryFragment.isAdded() && mDetailsFragment.isAdded()) {
Fragment.SavedState sumState = getSupportFragmentManager().saveFragmentInstanceState(mSummaryFragment);
Fragment.SavedState detState = getSupportFragmentManager().saveFragmentInstanceState(mDetailsFragment);
mSummaryFragment = new SummaryFragment();
mSummaryFragment.setInitialSavedState(sumState);
mDetailsFragment = new DetailsFragment();
mDetailsFragment.setInitialSavedState(detState);
}
FragmentTransaction ft = mFragmentManager.beginTransaction();
ft.add(R.id.summary_container, mSummaryFragment);
ft.add(R.id.details_container, mDetailsFragment);
ft.commit();
I do not understand why this works and the old method doesn't, however this may be helpful for someone else.
this should work and orientation change will not affect the fragment., if you face any problem just let me know.
public class MainActivity extends FragmentActivity {
Fragment fragment = new Fragment1();
Fragment fragment2=new Fragment2();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fm = super.getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.frame1, fragment);
ft.replace(R.id.frame2, fragment2);
ft.commit();
}
public void onSaveInstanceState(Bundle outState){
getSupportFragmentManager().putFragment(outState,"fragment1",fragment);
getSupportFragmentManager().putFragment(outState,"fragment2",fragment2);
}
public void onRetoreInstanceState(Bundle inState){
fragment = getSupportFragmentManager().getFragment(inState,"fragment1");
fragment2 = getSupportFragmentManager().getFragment(inState,"fragment2");
}
class Fragment1 extends Fragment{
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
ListView listView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.summary_view,container,false);
return view;
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
class Fragment2 extends Fragment{
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
ListView listView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.detail_view,container,false);
return view;
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
}
I'm using actionbar tabs because I need the navigation elements to be on every page. I'm using ActionBarSherlock for backwards compatibility (minimum API 8, target API 17). My MainActivity extends SherlockFragmentActivity. In my onCreate() for that, I have
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionBar.setDisplayShowTitleEnabled(true);
Tab tab1 = actionBar.newTab().setText("My Pages")
.setTabListener(new MyPagesFragment());
Tab tab2 = actionBar.newTab().setText("Search")
.setTabListener(new SearchFragment());
Tab tab3 = actionBar.newTab().setText("About")
.setTabListener(new AboutFragment());
// Start with the second tab selected.
actionBar.addTab(tab1, 0, false);
actionBar.addTab(tab2, 1, true);
actionBar.addTab(tab3, 2, false);
All the tab fragments are SherlockListFragments that implement ActionBar.TabListener, and do this
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
ft.replace(android.R.id.content, this, "mypages");
}
#Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
ft.remove(this);
}
#Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// Force a complete reload.
onTabSelected(tab, ft);
}
The search page has an EditText and uses its value in an AsyncTask to fetch data from an API and add it to an SQLite database, before calling
((MainActivity) getActivity()).showDetailView(responseCode);
to show the details, which is a method in my MainActivity as follows:
protected void showDetailView(long codeID) {
SherlockFragment detailFragment = new DetailFragment();
Bundle args = new Bundle();
args.putLong("codeID", codeID);
detailFragment.setArguments(args);
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction ft = manager.beginTransaction();
ft.replace(android.R.id.content, detailFragment);
ft.addToBackStack(null);
ft.commit();
}
DetailFragment is a SherlockFragment that uses getArguments() to retrieve the codeID--
Bundle args = getArguments();
if (null != args) {
codeRowID = args.getLong("codeID");
}
--and reads the matching data from the database to display it. Said data often contains links to more details, clicking which causes showDetailView to be called again with the new codeID.
MyPages is a list of all the cached details pages, and it too calls showDetailView:
#Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
((MainActivity) getActivity()).showDetailView(pages[position].codeId);
}
Going forward, this appears to work fine. However, when I use the back button, sometimes the fragments stick around, so they're still visible behind the restored fragment. How do I stop this happening?
I think the problem is maybe that the tabs are not being added to the backstack? But when I try to do that, they throw an exception telling me they can't be added to the backstack, so I don't understand how you are supposed to handle this. I don't understand why this thing, which it seems to be should be an incredibly basic navigation thing that lots of people want to do -- the back key has been on every android phone and table I've ever seen, physically or software! --apparently has no known solution. Have I just fundamentally misunderstood their use? Are fragments just not supposed to be used in this situation? How else do you do persistent navigation elements without repeating the same code on every page?
Logging - start app -
07-20 23:33:49.521: D/NAVIGATION_TRACE(7425): MAIN - onCreate
07-20 23:33:50.013: D/NAVIGATION_TRACE(7425): SEARCH - onTabSelected
07-20 23:33:50.021: D/NAVIGATION_TRACE(7425): SEARCH - onCreateView
07-20 23:33:50.060: D/NAVIGATION_TRACE(7425): SEARCH - onActivityCreated
07-20 23:33:50.060: D/NAVIGATION_TRACE(7425): MAIN - onResume
Search now visible. Search for an item to bring up detail view -
07-20 23:34:52.123: D/NAVIGATION_TRACE(7425): SEARCH - handleResponseCode
07-20 23:34:52.123: D/NAVIGATION_TRACE(7425): MAIN - showDetailView - 31
Detail now visible; Search gone. Click mypages tab -
07-20 23:35:37.787: D/NAVIGATION_TRACE(7425): SEARCH - onTabUnselected
07-20 23:35:37.787: D/NAVIGATION_TRACE(7425): MYPAGES - onTabSelected
07-20 23:35:37.826: D/NAVIGATION_TRACE(7425): MYPAGES - onCreateView
07-20 23:35:37.873: D/NAVIGATION_TRACE(7425): MYPAGES - onActivityCreated
MyPages now visible; Detail gone. Click back button -
07-20 23:36:12.130: D/NAVIGATION_TRACE(7425): SEARCH - onCreateView
07-20 23:36:12.201: D/NAVIGATION_TRACE(7425): SEARCH - onActivityCreated
Search and MyPages now both showing.
MainActivity:
public class MainActivity extends SherlockFragmentActivity
{
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
Log.d("NAVIGATION_TRACE", "MAIN - onCreate");
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionBar.setDisplayShowTitleEnabled(true);
Tab tab1 = actionBar.newTab().setText("My Pages")
.setTabListener(new TabListener<MyPagesFragment>(
this, "mypages", MyPagesFragment.class));
Tab tab2 = actionBar.newTab().setText("Search")
.setTabListener(new TabListener<SearchFragment>(
this, "search", SearchFragment.class));
Tab tab3 = actionBar.newTab().setText("About")
.setTabListener(new TabListener<AboutFragment>(
this, "about", AboutFragment.class));
// Start with the second tab selected.
actionBar.addTab(tab1, 0, false);
actionBar.addTab(tab2, 1, true);
actionBar.addTab(tab3, 2, false);
}
#Override
public void onBackPressed()
{
FragmentManager fm = getSupportFragmentManager();
if (0 < fm.getBackStackEntryCount())
{
super.onBackPressed();
} else {
// prompt to quit
AlertDialog.Builder alertErrorResponse = new AlertDialog.Builder(this);
alertErrorResponse.setMessage("Close app?");
alertErrorResponse.setNegativeButton("Cancel", null);
alertErrorResponse.setPositiveButton("OK", new DialogInterface.OnClickListener()
{
#Override
public void onClick(DialogInterface dialog, int which)
{
finish();
}
});
alertErrorResponse.show();
}
}
public void showDetailView(long codeID) {
Log.d("NAVIGATION_TRACE", "MAIN - showDetailView - "+String.valueOf(codeID));
lastShownCode = codeID;
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction ft = manager.beginTransaction();
SherlockFragment detailFragment = new DetailFragment();
Bundle args = new Bundle();
args.putLong("codeID", codeID);
detailFragment.setArguments(args);
ft.replace(android.R.id.content, detailFragment, "details");
ft.addToBackStack(null);
ft.commit();
}
public class TabListener<T extends SherlockListFragment> implements ActionBar.TabListener
{
private final SherlockFragmentActivity mActivity;
private final String mTag;
private final Class<T> mClass;
private SherlockListFragment mFragment;
public TabListener (SherlockFragmentActivity activity, String tag, Class<T> clz)
{
Log.d("NAVIGATION_TRACE", "TabListener - "+tag+" - "+clz.getCanonicalName());
mActivity = activity;
mTag = tag;
mClass = clz;
FragmentTransaction ft = mActivity.getSupportFragmentManager().beginTransaction();
mFragment = (SherlockListFragment) mActivity.getSupportFragmentManager().findFragmentByTag(mTag);
if (mFragment != null && !mFragment.isDetached())
{
Log.d("NAVIGATION_TRACE", "DETACH - "+mTag);
removeDetail(ft);
ft.detach(mFragment);
}
ft.commit();
}
public void clearBackStack()
{
Log.d("NAVIGATION_TRACE", "clearBackStack - "+mTag);
FragmentManager fm = mActivity.getSupportFragmentManager();
if (null != fm && 0 < fm.getBackStackEntryCount())
{
fm.popBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
}
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft)
{
Log.d("NAVIGATION_TRACE", "onTabSelected - "+mTag);
clearBackStack();
ft = mActivity.getSupportFragmentManager().beginTransaction();
if (mFragment == null)
{
Log.d("NAVIGATION_TRACE", "ADD/SHOW - "+mClass.getName());
removeDetail(ft);
mFragment = (SherlockListFragment) SherlockListFragment.instantiate(mActivity, mClass.getName());
ft.add(android.R.id.content, mFragment, mTag);
ft.commit();
}
else
{
Log.d("NAVIGATION_TRACE", "ATTACH/SHOW - "+mClass.getName());
removeDetail(ft);
ft.attach(mFragment);
ft.show(mFragment);
ft.commit();
}
}
#Override
public void onTabUnselected(Tab tab, FragmentTransaction ft)
{
Log.d("NAVIGATION_TRACE", "onTabUnselected - "+mTag);
ft = mActivity.getSupportFragmentManager().beginTransaction();
if (null != mFragment)
{
Log.d("NAVIGATION_TRACE", "HIDE/DETACH - "+mTag);
removeDetail(ft);
ft.hide(mFragment);
ft.detach(mFragment);
ft.commitAllowingStateLoss();
}
}
#Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
public void removeDetail(FragmentTransaction ft) {
SherlockFragment detailFragment = (SherlockFragment) mActivity.getSupportFragmentManager().findFragmentByTag("details");
if (null != detailFragment && !detailFragment.isDetached()) {
Log.d("NAVIGATION_TRACE", "DETACH - details");
ft.detach(detailFragment);
}
}
}
}
Example fragment - MyPagesFragment :
public class MyPagesFragment extends SherlockListFragment implements
OnItemClickListener
{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
Log.d("NAVIGATION_TRACE", "MYPAGES - onCreateView");
View view = inflater.inflate(R.layout.mypages, null);
// code to set up list adapter here
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
Log.d("NAVIGATION_TRACE", "MYPAGES - onActivityCreated");
getListView().setOnItemClickListener(this);
}
#Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id)
{
Log.d("NAVIGATION_TRACE", "MYPAGES - onItemClick");
((MainActivity) getActivity()).showDetailView(pages[position].codeId);
}
}
DetailFragment
public class DetailFragment extends SherlockFragment implements
OnItemClickListener
{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.detail, null);
// bunch of display / list set up code goes here
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
lvLinks.setOnItemClickListener(this);
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
// Details page can open other details pages:
((MainActivity) getActivity()).showDetailView(pages[position].id);
}
}
Note: The changes added were made following an answer by Sheldon (who seems to have, annoyingly, deleted their answer and comments), which is why the TabListener code changed between the original section and the later posted code.
I've currently hacked a solution by emptying the backstack on every tab select, and treating back on a top tab as an exit-the-app request, which is okay, I guess, but I really would like users to be able to keep backing through the tabs if this is at all possible (because that way, eg, if I was five details pages deep and I stopped to quickly search for something which, it turned out, didn't exist, I can back to those detail pages and still go up one or more to follow different detail links.)
Try this..
FragmentManager manager = getSupportFragmentManager();
if (manager.getBackStackEntryCount() > 0)
getSupportFragmentManager().popBackStack();
else
finish();
I'm working on an application where in layout layout-small-portrait I want to launch different fragments contained in a single "container activity", named SingleActivity. I will handle this differnetly in layouts layout-land, layout-large etc. but that is unrelated to my problem.
I have an activity MainActivity which is, as the name indicates, the main activity (launcher) of my application. This will initially contain a ListFragment with different items for the user to press.
Based on the item that the user presses the SingleActivity will launch and its content will correspond to a specific Fragment related to this item. My problem starts here. When the user presses an item I have a reference to the corresponding fragment I want to be displayed in SingleFragment. Illustrated below:
String tag = myFragmentReference.getTag();
Intent i = new Intent(this, SingleActivity.class);
i.putExtra(SingleActivity.CONST_TAG, tag);
startActivity(i);
The activity launches successfully. In SingleActivity I have the following onCreate() method:
...
// Retrieve the fragment tag from the intent
String tag = getIntent().getStringExtra(CONST_TAG);
Fragment fragment = getSupportFragmentManager().findFragmentByTag(tag);
if(fragment == null) {
// always end up here, this is my problem.
}
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.add(R.id.fragmentContainer, fragment);
ft.commit();
...
I suspect that the fact that fragment is always null is because the fragment has not been inflated yet. If I am right what I need to do is define a fragment's tag before it is inflated, so that it can be found by findFragmentByTag(). Is that possible?
If anything is unclear please let me know.
I look forward to hearing some good ideas! If there are better or more clever ways to implement this I would love to hear your thoughts! Thanks :)
Since you are jumping to another activity, it will have its own Fragment BackStack and that fragment will not exist.
You will have to inflate the fragment in the new activity something along these lines:
String tag = intent.getStringExtra(CONST_TAG);
if (getSupportFragmentManager().findFragmentByTag(tag) == null) {
Fragment fragment = Fragment.instantiate(this, tag, extras);
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.add(R.id.fragmentContainer, fragment, tag);
ft.commit();
}
The tag string will need to have the package location of the fragment such as "com.android.myprojectname.myfragment"
First use SlidingMenu library: https://github.com/jfeinstein10/SlidingMenu
This will help you, and your app will be more cool, that´s the only way that I can help you make what you need so, here is the code:
Here is your MainActivity:
I´ll try to explain this sample code and you use for your need.
This is the ListFragment of your BehindContent (SlidingMenu):
public class ColorMenuFragment extends ListFragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.list, null);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
String[] colors = getResources().getStringArray(R.array.color_names);
ArrayAdapter<String> colorAdapter = new ArrayAdapter<String>(getActivity(),
android.R.layout.simple_list_item_1, android.R.id.text1, colors);
setListAdapter(colorAdapter);
//This array is only to fill SlidingMenu with a Simple String Color.
//I used MergeAdapter from Commonsware to create a very nice SlidingMenu.
}
#Override
public void onListItemClick(ListView lv, View v, int position, long id) {
//This switch case is a listener to select wish item user have been selected, so it Call
//ColorFragment, you can change to Task1Fragment, Task2Fragment, Task3Fragment.
Fragment newContent = null;
switch (position) {
case 0:
newContent = new ColorFragment(R.color.red);
break;
case 1:
newContent = new ColorFragment(R.color.green);
break;
case 2:
newContent = new ColorFragment(R.color.blue);
break;
case 3:
newContent = new ColorFragment(android.R.color.white);
break;
case 4:
newContent = new ColorFragment(android.R.color.black);
break;
}
if (newContent != null)
switchFragment(newContent);
}
// the meat of switching the above fragment
private void switchFragment(Fragment fragment) {
if (getActivity() == null)
return;
if (getActivity() instanceof FragmentChangeActivity) {
FragmentChangeActivity fca = (FragmentChangeActivity) getActivity();
fca.switchContent(fragment);
} else if (getActivity() instanceof ResponsiveUIActivity) {
ResponsiveUIActivity ra = (ResponsiveUIActivity) getActivity();
ra.switchContent(fragment);
}
}
}
Here is your BaseActivity Class:
It dont have swipe, as I could understand, you don't need this.
public class FragmentChangeActivity extends BaseActivity {
private Fragment mContent;
public FragmentChangeActivity() {
super(R.string.changing_fragments);
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// set the Above View
if (savedInstanceState != null)
mContent = getSupportFragmentManager().getFragment(savedInstanceState, "mContent");
if (mContent == null)
mContent = new ColorFragment(R.color.red);
// set the Above View
//This will be the first AboveView
setContentView(R.layout.content_frame);
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.content_frame, mContent)
.commit();
// set the Behind View
//This is the SlidingMenu
setBehindContentView(R.layout.menu_frame);
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.menu_frame, new ColorMenuFragment())
.commit();
// customize the SlidingMenu
//This is opcional
getSlidingMenu().setTouchModeAbove(SlidingMenu.TOUCHMODE_FULLSCREEN);
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
getSupportFragmentManager().putFragment(outState, "mContent", mContent);
}
public void switchContent(Fragment fragment) {
// the meat of switching fragment
mContent = fragment;
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.content_frame, fragment)
.commit();
getSlidingMenu().showContent();
}
}
Ok, So If you want to change the ColorFragment to anything else, do this:
First, choice the item that you want to use:
case 0:
newContent = new ColorFragment(R.color.red);
break;
to:
case 0:
newContent = new ArrayListFragment();
break;
I have made just a arraylist, it is just a simple example, you can do a lot of thing, then you can read about Fragment to learn how to do different things.
public class ArrayListFragment extends ListFragment {
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setListAdapter(new ArrayAdapter<String>(getActivity(),
android.R.layout.simple_list_item_1, Listnames.TITLES));
//Listnames is a class with String[] TITLES;
}
#Override
public void onListItemClick(ListView l, View v, int position, long id) {
Log.i("FragmentList2", "Item clicked: " + id);
String item = (String) getListAdapter().getItem(position);
Toast.makeText(getActivity(), item, Toast.LENGTH_LONG).show();
}
}
As you see, it can display a different fragment based on which item in the ListFragment (MainActivity) the user presses.
Well, if you misunderstood something, just tell me.