Unten ist mein Code, in den 3 Fragment classes
jeweils die drei Registerkarten eingebettet sind ViewPager
. Ich habe eine Menüoption. Wie in der Abbildung gezeigt onOptionsItemSelected()
, muss ich durch Auswahl einer Option das derzeit sichtbare Fragment aktualisieren. Um dies zu aktualisieren, muss ich eine Methode aufrufen, die sich in der Fragmentklasse befindet. Kann jemand bitte vorschlagen, wie man diese Methode aufruft?
public class MainActivity extends ActionBarActivity {
ViewPager ViewPager;
TabsAdapter TabsAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ViewPager = new ViewPager(this);
ViewPager.setId(R.id.pager);
setContentView(ViewPager);
final ActionBar bar = getSupportActionBar();
bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
//Attaching the Tabs to the fragment classes and setting the tab title.
TabsAdapter = new TabsAdapter(this, ViewPager);
TabsAdapter.addTab(bar.newTab().setText("FragmentClass1"),
FragmentClass1.class, null);
TabsAdapter.addTab(bar.newTab().setText("FragmentClass2"),
FragmentClass2.class, null);
TabsAdapter.addTab(bar.newTab().setText("FragmentClass3"),
FragmentClass3.class, null);
if (savedInstanceState != null) {
bar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0));
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.addText:
**// Here I need to call the method which exists in the currently visible Fragment class**
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt("tab", getSupportActionBar().getSelectedNavigationIndex());
}
public static class TabsAdapter extends FragmentPagerAdapter
implements ActionBar.TabListener, ViewPager.OnPageChangeListener {
private final Context mContext;
private final ActionBar mActionBar;
private final ViewPager mViewPager;
private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();
static final class TabInfo {
private final Class<?> clss;
private final Bundle args;
TabInfo(Class<?> _class, Bundle _args) {
clss = _class;
args = _args;
}
}
public TabsAdapter(ActionBarActivity activity, ViewPager pager) {
super(activity.getSupportFragmentManager());
mContext = activity;
mActionBar = activity.getSupportActionBar();
mViewPager = pager;
mViewPager.setAdapter(this);
mViewPager.setOnPageChangeListener(this);
}
public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
TabInfo info = new TabInfo(clss, args);
tab.setTag(info);
tab.setTabListener(this);
mTabs.add(info);
mActionBar.addTab(tab);
notifyDataSetChanged();
}
@Override
public void onPageScrollStateChanged(int state) {
// TODO Auto-generated method stub
}
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
// TODO Auto-generated method stub
}
@Override
public void onPageSelected(int position) {
// TODO Auto-generated method stub
mActionBar.setSelectedNavigationItem(position);
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// TODO Auto-generated method stub
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
Object tag = tab.getTag();
for (int i=0; i<mTabs.size(); i++) {
if (mTabs.get(i) == tag) {
mViewPager.setCurrentItem(i);
}
}
tabPosition = tab.getPosition();
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
// TODO Auto-generated method stub
}
@Override
public Fragment getItem(int position) {
TabInfo info = mTabs.get(position);
return Fragment.instantiate(mContext, info.clss.getName(), info.args);
}
@Override
public int getCount() {
return mTabs.size();
}
}
}
Angenommen, unten ist die Fragmentklasse mit der Methode, die updateList()
ich aufrufen möchte:
public class FragmentClass1{
ArrayList<String> originalData;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View fragmentView = inflater.inflate(R.layout.frag1, container, false);
originalData = getOriginalDataFromDB();
return fragmentView;
}
public void updateList(String text)
{
originalData.add(text);
//Here I could do other UI part that need to added
}
}