我的viewpager中每个片段的不同标题
我正在使用viewpager“tabs + swipe”，我想在actionBar中为每个片段设置不同的标题，这样当我切换时，标题会发生变化。
我尝试了几件事没有成功，只有最后一个标题显示……当我切换时它不再改变…
首先，让您的活动实现OnPageChangeListener 。
然后，在创建ViewPager ，可以使用mViewPager.setOnPageChangeListener(this)以便在页面更改时您的活动将收到回调。
最后，您需要实现OnPageChangeListener回调。 你的onPageSelected()方法应该是这样的：
@Override public abstract void onPageSelected(int position) { setTitle(getTitleFromPosition(position)); }
其他两个回调可以为空。
虽然问题有点过时，但我建议我的解决方案。 场景：选项卡+滑动，每个选项卡都有片段导航堆栈。 因此，操作栏标题不仅可以通过切换和滑动选项卡进行更改，还可以在每个选项卡中进行导航。 为每个片段提供标题，我声明了TitleProvider接口，因此如果片段具有自定义标题，则必须实现此接口。
public interface TitleProvider { CharSequence getTitle(); }
下面是自定义FragmentPagerAdapter ，它处理切换，滑动，导航和标题更新：
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 fragments = new ArrayList (); private final Hashtable>> fragmentBackstack = new Hashtable>>(); 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> backstack; if (fragmentBackstack.containsKey(fromFragment)) { backstack = fragmentBackstack.get(fromFragment); fragmentBackstack.remove(fromFragment); } else { backstack = new Stack>(); } 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> 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()); } } }
@Override public void onPageSelected(int position) { tabHost.setSelectedNavigationItem(position); if (position == 0){ setTitle(R.string.where_is_the_bus); } else if (position == 1){ setTitle(R.string.bus_card); } else if (position == 2){ setTitle(R.string.favo); }
你可以这样做“这很容易吗？”