हालांकि सवाल थोड़ा पुराना है, मैं अपना समाधान सुझाऊंगा। परिदृश्य: टैब + स्वाइप और प्रत्येक टैब में खंड नेविगेशन स्टैक होता है। तो कार्रवाई बार शीर्षक न केवल टैब स्विचिंग और स्वाइप करने के माध्यम से बदला जा सकता है लेकिन प्रत्येक टैब में नेविगेशन के साथ। प्रति खंड शीर्षक प्रदान करने के लिए मैंने TitleProvider
इंटरफ़ेस घोषित किया, इसलिए यदि खंड में कस्टम शीर्षक है तो इसे इस इंटरफ़ेस को कार्यान्वित करना होगा।
public interface TitleProvider {
CharSequence getTitle();
}
नीचे वहाँ कस्टम FragmentPagerAdapter
, कि स्विचिंग, स्वाइप, नेविगेशन और शीर्षक अद्यतन संभालती है:
public class TabsAdapter extends FragmentPagerAdapter implements
TabHost.OnTabChangeListener, ViewPager.OnPageChangeListener {
private final FragmentActivity activity;
private final TabHost tabHost;
private final ViewPager viewPager;
private final ArrayList<Fragment> fragments = new ArrayList<Fragment>();
private final Hashtable<Fragment, Stack<Class<?>>> fragmentBackstack = new Hashtable<Fragment, Stack<Class<?>>>();
static class DummyTabFactory implements TabHost.TabContentFactory {
private final Context context;
public DummyTabFactory(Context context) {
this.context = context;
}
@Override
public View createTabContent(String tag) {
View v = new View(context);
v.setMinimumWidth(0);
v.setMinimumHeight(0);
return v;
}
}
public TabsAdapter(FragmentActivity activity, TabHost tabHost,
ViewPager pager) {
super(activity.getSupportFragmentManager());
this.activity = activity;
this.tabHost = tabHost;
viewPager = pager;
tabHost.setOnTabChangedListener(this);
viewPager.setAdapter(this);
viewPager.setOnPageChangeListener(this);
}
public void addTab(String tag, int drawableId, Fragment fragment,
int tabIndicatorId) {
TabSpec tabSpec = tabHost.newTabSpec(tag);
tabSpec.setContent(new DummyTabFactory(activity.getApplicationContext()));
View tabIndicator = LayoutInflater.from(
activity.getApplicationContext()).inflate(tabIndicatorId,
tabHost.getTabWidget(), false);
TextView title = (TextView) tabIndicator.findViewById(R.id.tab_title);
if (fragment instanceof TitleProvider) {
title.setText(((TitleProvider) fragment).getTitle());
}
ImageView icon = (ImageView) tabIndicator.findViewById(R.id.tab_icon);
icon.setImageResource(drawableId);
tabSpec.setIndicator(tabIndicator);
fragments.add(fragment);
tabHost.addTab(tabSpec);
notifyDataSetChanged();
}
@Override
public int getCount() {
return fragments.size();
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getItemPosition(Object object) {
int returnCode;
if (fragments.contains(object)) {
returnCode = POSITION_UNCHANGED;
} else {
returnCode = POSITION_NONE;
}
return returnCode;
}
@Override
public void onTabChanged(String tabId) {
int position = tabHost.getCurrentTab();
viewPager.setCurrentItem(position);
updateTitle();
}
@Override
public void onPageScrolled(int position, float positionOffset,
int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
// Unfortunately when TabHost changes the current tab, it kindly
// also takes care of putting focus on it when not in touch mode.
// The jerk.
// This hack tries to prevent this from pulling focus out of our
// ViewPager.
TabWidget widget = tabHost.getTabWidget();
int oldFocusability = widget.getDescendantFocusability();
widget.setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS);
tabHost.setCurrentTab(position);
widget.setDescendantFocusability(oldFocusability);
}
@Override
public void onPageScrollStateChanged(int state) {
}
public void navigate(Fragment fromFragment, Fragment toFragment) {
startUpdate(viewPager);
FragmentTransaction transaction = activity.getSupportFragmentManager()
.beginTransaction();
transaction.remove(fromFragment);
transaction.commit();
Stack<Class<?>> backstack;
if (fragmentBackstack.containsKey(fromFragment)) {
backstack = fragmentBackstack.get(fromFragment);
fragmentBackstack.remove(fromFragment);
} else {
backstack = new Stack<Class<?>>();
}
backstack.push(fromFragment.getClass());
fragmentBackstack.put(toFragment, backstack);
fragments.set(fragments.indexOf(fromFragment), toFragment);
finishUpdate(viewPager);
notifyDataSetChanged();
updateTitle();
}
public Boolean navigateBack() {
startUpdate(viewPager);
Fragment fromFragment = fragments.get(viewPager.getCurrentItem());
if (!fragmentBackstack.containsKey(fromFragment))
return false;
Stack<Class<?>> backstack = fragmentBackstack.get(fromFragment);
if (backstack.isEmpty())
return false;
fragmentBackstack.remove(fromFragment);
Fragment toFragment = Fragment.instantiate(activity, backstack.pop()
.getName());
fragmentBackstack.put(toFragment, backstack);
fragments.set(fragments.indexOf(fromFragment), toFragment);
FragmentTransaction transaction = activity.getSupportFragmentManager()
.beginTransaction();
transaction.remove(fromFragment);
transaction.commit();
finishUpdate(viewPager);
notifyDataSetChanged();
updateTitle();
return true;
}
protected Fragment getCurrentFragment() {
return fragments.get(viewPager.getCurrentItem());
}
protected void updateTitle() {
Fragment fragment = getCurrentFragment();
if (fragment instanceof TitleProvider) {
activity.setTitle(((TitleProvider) fragment).getTitle());
}
}
}
ग्रेट, धन्यवाद !! – lost17
लवली जवाब! :) –