嗨，这是我的MainActivity For Tab。它有3个片段。
Second Fragment将一些数据添加到数据库，第三个片段可以检查它是否发生了变化。但即使我用第二个片段向数据库添加一些数据，第三个片段也没有变化。
如何只需点击第三个标签即可刷新我的第三个片段 下面是mainActivity，
package com.example.location;
import java.util.Locale;
import com.example.meta.LocationNState;
import android.app.ActionBar;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v13.app.FragmentPagerAdapter;
import android.support.v13.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends Activity implements ActionBar.TabListener {
/**
* The {@link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a {@link FragmentPagerAdapter}
* derivative, which will keep every loaded fragment in memory. If this
* becomes too memory intensive, it may be best to switch to a
* {@link android.support.v13.app.FragmentStatePagerAdapter}.
*/
SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {@link ViewPager} that will host the section contents.
*/
ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.e("Activity : ", "MainActivity");
// Set up the action bar.
final ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Create the adapter that will return a fragment for each of the three
// primary sections of the activity.
mSectionsPagerAdapter = new SectionsPagerAdapter(getFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
// When swiping between different sections, select the corresponding
// tab. We can also use ActionBar.Tab#select() to do this if we have
// a reference to the Tab.
mViewPager
.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
// For each of the sections in the app, add a tab to the action bar.
for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
// Create a tab with text corresponding to the page title defined by
// the adapter. Also specify this Activity object, which implements
// the TabListener interface, as the callback (listener) for when
// this tab is selected.
actionBar.addTab(actionBar.newTab()
.setText(mSectionsPagerAdapter.getPageTitle(i))
.setTabListener(this));
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onTabSelected(ActionBar.Tab tab,
FragmentTransaction fragmentTransaction) {
// When the given tab is selected, switch to the corresponding page in
// the ViewPager.
mViewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(ActionBar.Tab tab,
FragmentTransaction fragmentTransaction) {
}
@Override
public void onTabReselected(ActionBar.Tab tab,
FragmentTransaction fragmentTransaction) {
}
/**
* A {@link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentStatePagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
switch(position){
case 0 :
return new LocationFragment().newInstance(position);
case 1 :
LocationNState location = LocationNState.get();
return new NewLocation().newInstance(location);
case 2 :
return new ShowSavedLocation().newInstance(position);
}
return new LocationFragment().newInstance(0);
}
@Override
public int getCount() {
// Show 3 total pages.
return 3;
}
@Override
public CharSequence getPageTitle(int position) {
Locale l = Locale.getDefault();
switch (position) {
case 0:
return getString(R.string.title_section1).toUpperCase(l);
case 1:
return getString(R.string.title_section2).toUpperCase(l);
case 2:
return getString(R.string.title_section3).toUpperCase(l);
}
return null;
}
}
}
下面是第三个片段。
package com.example.location;
import java.util.ArrayList;
import java.util.List;
import android.app.Fragment;
import android.content.Context;
import android.location.Geocoder;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import com.example.db.MySQLiteHelper;
import com.example.meta.LocationNState;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
public class ShowSavedLocation extends Fragment implements OnItemClickListener{
private GoogleMap map = null;
private MySQLiteHelper db = null;
private Context context = null;
private ListView listView = null;
private Button del_Button = null;
private Geocoder geocoder = null;
private List<LocationNState> locationNStates = null;
private ArrayList<LocationNState> array_locationNStates = null;
private LocationNStateAdapter adapter = null;
public ShowSavedLocation newInstance(int sectionNumber) {
ShowSavedLocation fragment = new ShowSavedLocation();
return fragment;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
context = getActivity();
View rootView = inflater.inflate(R.layout.fragment_showsavedlocation, container, false);
map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map_showSavedLocation)).getMap();
db = new MySQLiteHelper(context);
geocoder = new Geocoder(context);
listView = (ListView) rootView.findViewById(R.id.list_view);
locationNStates = db.getAllLocationNStates();
array_locationNStates = new ArrayList<LocationNState>(locationNStates);
adapter = new LocationNStateAdapter(context, R.layout.listview_locationnstate, array_locationNStates);
listView.setAdapter(adapter);
listView.setOnItemClickListener(this);
setMapSetting(LocationNState.get());
return rootView;
}
@Override
public void onDestroyView() {
super.onDestroyView();
MapFragment f = (MapFragment) getFragmentManager().findFragmentById(R.id.map_showSavedLocation);
if (f != null)
getFragmentManager().beginTransaction().remove(f).commit();
}
public void setMapSetting(LocationNState locationNState){
if(locationNState.getAddress() == null ||
locationNState.getLocation().getLatitude() == 0 ||
locationNState.getLocation().getLongitude() == 0)
return;
map.clear();
map.setMyLocationEnabled(true);
map.setBuildingsEnabled(true);
map.getUiSettings().setCompassEnabled(true);
map.getUiSettings().setZoomControlsEnabled(true);
map.addMarker(new MarkerOptions()
.position(new LatLng(locationNState.getLocation().getLatitude() , locationNState.getLocation().getLongitude()))
.title(locationNState.getAddress())
//.snippet(address_Snippet)
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE)));
map.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(locationNState.getLocation().getLatitude(), locationNState.getLocation().getLongitude()), 17 ));
}
public class LocationNStateAdapter extends ArrayAdapter<LocationNState> {
private ArrayList<LocationNState> LocationNStateArrayList = null;
public LocationNStateAdapter(Context context, int resource,
ArrayList<LocationNState> objects) {
super(context, resource, objects);
// TODO Auto-generated constructor stub
this.LocationNStateArrayList = objects;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View rootView = convertView;
if(rootView == null){
LayoutInflater vi = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
rootView = vi.inflate(R.layout.listview_locationnstate, null);
}
LocationNState locationNState = LocationNStateArrayList.get(position);
if(locationNState != null){
TextView addressTextView = (TextView) rootView.findViewById(R.id.listview_address);
TextView stateTextView = (TextView) rootView.findViewById(R.id.listview_state);
if(addressTextView != null )
addressTextView.setText(" 위치 : " +locationNState.getAddress().toString());
if(stateTextView != null){
int state = locationNState.getState();
String mState = "벨소리";
switch(state){
case 0:
mState = "벨소리";
break;
case 1:
mState = "진동";
break;
case 2:
mState = "무음";
break;
default :
break;
}
stateTextView.setText(" 상태 : " + mState);
}
}
final int index = position;
del_Button = (Button) rootView.findViewById(R.id.listview_del);
del_Button.setOnClickListener(new Button.OnClickListener() {
public void onClick(View v)
{
LocationNState locationNState = (LocationNState)listView.getAdapter().getItem(index);
LocationNStateArrayList.remove(index);
db.deleteLocationNState(locationNState);
refreshListView();
}
});
return rootView;
}
}
@Override
public void onPause(){
refreshListView();
super.onPause();
}
public void refreshListView(){
final ArrayAdapter adapter = ((ArrayAdapter)listView.getAdapter());
adapter.notifyDataSetChanged();
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// TODO Auto-generated method stub
/* View rootView = view;
if(rootView == null){
LayoutInflater vi = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
rootView = vi.inflate(R.layout.listview_locationnstate, null);
}*/
LocationNState locationNState = (LocationNState)listView.getAdapter().getItem(position); //obj 자체가 locationNState네.
setMapSetting(locationNState);
}
}
感谢您的帮助
答案 0 :(得分：0)
第三个片段在refreshListView()而不是onPause()中调用onResume()。