问题
I have 2 fragments which are called from the action bar of an activity. Both are gridviews, the first one displays an application list with a dedicated adapter, and the second one displays a file list with another adapter. My problem is that when I launch a file then when I back to my activity I switch from one fragment to another, when I come back to the previous one, its content disappears. And when I rotate tablet I have the some problem, because my Fragment restart so for this I think that removing fragment give the possibility to create a new Fragment up to date.
How can I manage to update the content of the first fragment while coming back from the second one ? And how to remove fragment after the rotation in order to recreate the Action with new Fragment? the code of my Activity is given by the code below:
public class LaunchActivity extends Activity {
public static Activity LAUNCH;
private PagerAdapter mPagerAdapter;
Menu menu;
public static boolean updated = false;
private static final String TAG = "launchactivity";
public static String Path2;
public static String[] mMenu;
public static String file_name = "seconde";
public static String teacher_file = "teacher";
public static String newString;
public static String SESSIONNAME;
public static ArrayList<String> myList;
private static ArrayList<String> test;
String user = "eleve";
String savedUser;
String mode = "normal";
String savedMode;
private int year;
private int month;
private int day;
static final int DATE_DIALOG_ID = 999;
public static boolean active = false;
////////////////////
// OptionsActivity fi = new OptionsActivity();
private ApplicationManager appManager;
ArrayList<String> files = new ArrayList<String>();
private List<String> listTitle = new ArrayList<String>();
private final BroadcastReceiver mApplicationsReceiver = new ApplicationsIntentReceiver();
private boolean mHomeDown;
private boolean mBackDown;
private ActionBar actionbar ;
File mntFolder = new File("/mnt/");
File[] external = mntFolder.listFiles();
public static boolean pause2=false;
public static String path;
public static File fpath;
private boolean admin = false;
private boolean eleve = false;
private boolean prof = false;
///////////////////////
private static final String TAB_KEY_INDEX = "tab_key";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main1);
LAUNCH = this;
if (savedInstanceState == null) {
Bundle extras = getIntent().getExtras();
if(extras == null) {
newString= null;
} else {
newString= extras.getString(PreferenceConnector.PREF_NAME);
}
} else {
newString= (String) savedInstanceState.getSerializable(PreferenceConnector.PREF_NAME);
}
// Log.i("**----test----saved value**" , newString);
if(newString != null){
newString = newString.substring(1 , (newString.length()-1));
ArrayList<String> sList = new ArrayList<String>(Arrays.asList(newString.split(",")));
myList = new ArrayList<String>(Arrays.asList(newString.split(", ")));
String v = " ";
myList.add(0, v.concat(sList.get(0)));
myList.add(0, sList.get(0).concat(v));
/////// try this in order to get the good size///////////////////////////////
for(int i= 0 ; i< myList.size() ; i++){
Log.i("------> l'element n " + String.valueOf(i),myList.get(i));
}
}
if (savedInstanceState != null) {
savedUser = savedInstanceState.getString("TEXT");
savedMode = savedInstanceState.getString("MODE");
String str;
str = savedInstanceState.getString("ListActivity");
test = savedInstanceState.getStringArrayList("List");
// myList = (ArrayList<String>) Arrays.asList(str.split("\\s*,\\s*"));
} else {
savedUser = "eleve";
savedMode = "normal";
}
//Log.d("savedUser", savedUser);
//Log.d("savedMode", savedMode);
// ActionBar
actionbar = getActionBar();
actionbar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionbar.setDisplayUseLogoEnabled(false);
actionbar.setDisplayShowTitleEnabled(false) ;
// create new tabs and and set up the titles of the tabs
ActionBar.Tab mFindTab = actionbar.newTab().setText(
getString(R.string.ui_tabname_find));
ActionBar.Tab mChatTab = actionbar.newTab().setText(
getString(R.string.ui_tabname_chat));
ActionBar.Tab mMeetTab = actionbar.newTab().setText(
getString(R.string.ui_tabname_meet));
ActionBar.Tab mPartyTab = actionbar.newTab().setText(
getString(R.string.ui_tabname_find));
// create the fragments
Fragment mMeetFragment = new ApplicatinFragment();
Fragment mFindFragment = new MatFragment();
Fragment mChatFragment = new DocumentFragment1();
Fragment mPartyFragment = new PartyFragment();
// bind the fragments to the tabs - set up tabListeners for each tab
mFindTab.setTabListener(new MyTabsListener(mFindFragment,
getApplicationContext()));
mChatTab.setTabListener(new MyTabsListener(mChatFragment,
getApplicationContext()));
mMeetTab.setTabListener(new MyTabsListener(mMeetFragment,
getApplicationContext()));
// mPartyTab.setTabListener(new MyTabsListener(mPartyFragment,
// getApplicationContext()));
// add the tabs to the action bar
actionbar.addTab(mMeetTab);
actionbar.addTab(mFindTab);
if (savedInstanceState != null) {
// Toast.makeText(getApplicationContext(),
// "tab is " + savedInstanceState.getInt(TAB_KEY_INDEX, 0),
// Toast.LENGTH_SHORT).show();
actionbar.setSelectedNavigationItem(savedInstanceState.getInt(
TAB_KEY_INDEX, 0));
}
}
public void onResume() {
this.stopService(new Intent(this, fr.mi.DetectorService.class));
Intent startService = new Intent(this, fr.mi.DetectorService.class);
this.startService(startService);
if(fr.mi.LockScreenActivity.LOCK != null){
fr.mi.LockScreenActivity.LOCK.finish();
}
Log.i("onResume", "onResume()");
if (AppList.ac != null) {
AppList.ac.finish();
}
//Toast.makeText(this, "onResume()", Toast.LENGTH_LONG).show();
super.onResume();
}
@Override
public void onPause() {
super.onPause(); // Always call the superclass method first
}
public void onDestroy() {
super.onStop();
// tToast("onDestroy.");
}
private class ApplicationsIntentReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(getApplicationContext(), "test" + "this" , Toast.LENGTH_LONG).show();
appManager.loadApplications(false);
}
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
/*
Toast.makeText(
this,
"onSaveInstanceState: tab is"
+ getActionBar().getSelectedNavigationIndex(),
Toast.LENGTH_SHORT).show(); */
outState.putStringArrayList("List",LaunchActivity.myList);
outState.putString("ListActivity", LaunchActivity.myList.toString());
}
private void registerIntentReceivers() {
IntentFilter filter = new IntentFilter(Intent.ACTION_PACKAGE_ADDED);
filter.addAction(Intent.ACTION_PACKAGE_REMOVED);
filter.addAction(Intent.ACTION_PACKAGE_CHANGED);
filter.addDataScheme("package");
registerReceiver(mApplicationsReceiver, filter);
}
}
class MyTabsListener implements ActionBar.TabListener {
public Fragment fragment;
public Context context;
public MyTabsListener(Fragment fragment, Context context) {
this.fragment = fragment;
this.context = context;
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// Toast.makeText(context, "Reselected!", Toast.LENGTH_SHORT).show();
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
//Toast.makeText(context, "Selected!", Toast.LENGTH_SHORT).show();
ft.replace(R.id.fragment_container, fragment);
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
//Toast.makeText(context, "Unselected!", Toast.LENGTH_SHORT).show();
ft.remove(fragment);
}
}
My first Fragment used to view installed application in a gridView. is given by the code below:
public class ApplicatinFragment extends Fragment {
TextView title;
private static ApplicationManager appManager;
Menu menu;
public static boolean updated = false;
private static final String TAG = "launchactivity";
public static String Path;
public static String[] mMenu;
public static String file_name = "seconde";
public static String teacher_file = "teacher";
//private static final String PREF_APPLICATION_LIST = "application_list";
//OptionsActivity fi = new OptionsActivity();
private static final String PREF_SERVICE_ENABLED = "service_enabled";
private static final String PREF_APPLICATION_LIST = "application_list";
private static final String PREF_APPLICATION_LIST1 = "application_list1";
private static final String PREF_APPLICATION_LISTPROF = "application_list_prof";
private static final String PREF_AUTO_START = "start_service_after_boot";
private static final String PREF_PASSWORD = "password";
private static final String PREF_UNIVERSEL_PASSWORD = "universelpassword";
public static boolean SBACKSTUCK = false ;
private SharedPreferences mPref;
private boolean mServiceEnabled, mAutoStart;
public static String[] mApplicationList;
private String[] mApplicationList1;
private String[] mApplicationListProf;
public static String mPassword;
private String mUniverselPassword;
private int mRelockTimeout;
private final BroadcastReceiver mApplicationsReceiver = new ApplicationsIntentReceiver();
GridView gridView;
ArrayList<String> files = new ArrayList<String>();
private static GridViewAppInfoAdapter adapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.i("PageAdminFragment", "onCreate");
appManager = new ApplicationManager(getActivity(), getActivity()
.getPackageManager(),LaunchActivity.myList);
appManager.loadApplications(true);
registerIntentReceivers();
adapter = new GridViewAppInfoAdapter(getActivity(),
appManager.getStudentApplicationsCode());
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getActivity());
SharedPreferences.Editor editor = sharedPreferences.edit();
// mApplicationList = mPref.getString(PREF_APPLICATION_LIST, "").split(";");
String combined = "";
combined = combined + "com.android.vending" + ";";
combined = combined + "com.android.settings" + ";";
combined = combined + "com.android.packageinstaller" + ";" ;
//combined = combined + "air.Arbres";
for( int i = 0; i < SessionChoose.ProtectedApplication.size(); i++){
combined = combined + SessionChoose.ProtectedApplication.toString() + ";" ;
}
Log.d("-*-*les applications à proteger-*-*", combined);
//Toast.makeText(getActivity(),"-*-*les applications à proteger-*-*"+ combined,Toast.LENGTH_LONG).show();
// editor.putString(PREF_APPLICATION_LIST, combined).commit();
// LoadPreferences(getActivity());
//Toast.makeText(getApplicationContext(),"PREF_APPLICATION_LIST " + strSavedMem2 , Toast.LENGTH_LONG ).show();
// SaveApplicationPreferences(PREF_APPLICATION_LIST,strSavedMem2 ,ProtectedApplication,getApplicationContext());
//LoadPreferences(getActivity());
//Toast.makeText(getApplicationContext(),"PREF_APPLICATION_LIST " + strSavedMem2 , Toast.LENGTH_LONG ).show();
//LoadPreferences(getActivity());
/**
* Creat file to save session Content
*/
this.getActivity().getApplicationContext().stopService(new Intent(this.getActivity(), fr.mi.DetectorService.class));
//getActivity().stopService(new Intent(this.getActivity(), fr.mi.DetectorService.class));
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//Toast.makeText(getActivity(), "I need the good Adapter", Toast.LENGTH_SHORT).show();
Log.d(TAG, appManager.getStudentApplications().toString());
int display_mode = getResources().getConfiguration().orientation;
View view = null;
/////////////////////////////////////////////////////////////////////////////
if (display_mode == 1) {
view = inflater.inflate(R.layout.main_grid,
container, false);
// this.getWindow().setFlags(
// WindowManager.LayoutParams.FLAG_FULLSCREEN,
// WindowManager.LayoutParams.FLAG_FULLSCREEN);
// this.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
gridView = (GridView) view.findViewById(R.id.gridview);
//mGrid = (GridView) findViewById(R.id.gridview);
gridView.setColumnWidth(95);
// mGrid.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION);
} else {
view = inflater.inflate(R.layout.main_grid_land,
container, false);
// this.getWindow().setFlags(
// WindowManager.LayoutParams.FLAG_FULLSCREEN,
// WindowManager.LayoutParams.FLAG_FULLSCREEN);
//setContentView(R.layout.main_grid_land);
gridView = (GridView) view.findViewById(R.id.gridview1);
gridView.setColumnWidth(95);
Log.d("Mode", "land");
// mGrid.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION);
}
gridView.setAdapter(adapter);
gridView.setSelection(0);
/////////////try this ///////////////////////
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this.getActivity().getApplicationContext());
SharedPreferences.Editor editor = sharedPreferences.edit();
gridView.setOnItemClickListener((new OnItemClickListener() {
// si on clique sur l'item
@Override
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
ApplicationInfo app = (ApplicationInfo) parent
.getItemAtPosition(position);
startActivity(app.intent);
}
}));
if(ViewPagerActivity.VIEWDOC == true ){
Intent intent = new Intent();
intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
intent.setClass(getActivity(), LaunchActivity.class);
startActivity(intent);
}
Intent startService = new Intent(this.getActivity().getApplicationContext(), fr.mi.DetectorService.class);
getActivity().startService(startService);
ViewPagerActivity.VIEWDOC = false ;
return view;
}
private void bindApplications(LayoutInflater inflater, ViewGroup container) {
View view = inflater.inflate(R.layout.main_grid,
container, false);
if (gridView == null) {
gridView = (GridView) view.findViewById(R.id.gridview);
}
adapter = new GridViewAppInfoAdapter(getActivity(),
appManager.getStudentApplicationsCode());
adapter.notifyDataSetChanged();
gridView.setAdapter(adapter);
gridView.setSelection(0);
}
private void registerIntentReceivers() {
IntentFilter filter = new IntentFilter(Intent.ACTION_PACKAGE_ADDED);
filter.addAction(Intent.ACTION_PACKAGE_REMOVED);
filter.addAction(Intent.ACTION_PACKAGE_CHANGED);
filter.addDataScheme("package");
getActivity().registerReceiver(mApplicationsReceiver, filter);
}
@Override
public void onStop() {
super.onStop();
Log.i(TAG, "Onstop");
}
@Override
public void onDestroy() {
Log.i(TAG, "OnsdESTROY");
super.onDestroy();
}
@Override
public void onResume() {
Log.i(TAG, "OnResume");
super.onResume();
}
private void reloadPreferences() {
mServiceEnabled = mPref.getBoolean(PREF_SERVICE_ENABLED, false);
mApplicationList = mPref.getString(PREF_APPLICATION_LIST, "").split(";");
mApplicationList1 = mPref.getString(PREF_APPLICATION_LIST1, "").split(";");
mApplicationListProf = mPref.getString(PREF_APPLICATION_LISTPROF,"").split(";");
//Log.d("**************La Liste des applications à proteger***********", mApplicationList.toString());
Log.i("+-+-+-+-+- ***Censored***++++++++++", mApplicationList.toString() );
mAutoStart = mPref.getBoolean(PREF_AUTO_START, false);
mPassword = mPref.getString(PREF_PASSWORD, "2492");
mUniverselPassword = mPref.getString(PREF_UNIVERSEL_PASSWORD , "9113");
if (mPref.getBoolean("relock_policy", true)){
try{
mRelockTimeout = Integer.parseInt(mPref.getString("relock_timeout", "-1"));
}catch(Exception e){
mRelockTimeout = -1;
}
}else{
mRelockTimeout = -1;
}
}
/**
* Receives notifications when applications are added/removed.
*/
private class ApplicationsIntentReceiver extends BroadcastReceiver {
LayoutInflater inflater;
ViewGroup container ;
public ApplicationsIntentReceiver(){
}
/* public ApplicationsIntentReceiver(LayoutInflater inflater, ViewGroup container){
this.inflater = inflater ;
this.container = container ;
}*/
@Override
public void onReceive(Context context, Intent intent) {
// appManager = new ApplicationManager(getActivity(), getActivity()
//.getPackageManager(), null);
SBACKSTUCK = true;
appManager.loadApplications(false);
// gridView.setAdapter(null);
//GridViewAppInfoAdapter adapter1 = new GridViewAppInfoAdapter(getActivity(),
// appManager.getStudentApplicationsCode());
//adapter1.setApps((List<ApplicationInfo>) appManager.getStudentApplicationsCode());
//gridView.setAdapter(adapter1);
// Toast.makeText(getActivity(), "la valeur" + LaunchActivity.myList.toString() , Toast.LENGTH_LONG).show();
Log.d("la valeur de la list" ,LaunchActivity.myList.toString() );
//adapter = new GridViewAppInfoAdapter(getActivity(),
// appManager.getStudentApplicationsCode());
bindApplications( inflater , container);
}
}
////implement the bind Application
private void bindApplications(AdapterView<?> parent, int position){
ApplicationInfo app = (ApplicationInfo) parent
.getItemAtPosition(position);
startActivity(app.intent);
}
// ///////////////////////////////////////////////
/**
* Starts the selected activity/application in the grid view.
*/
private class ApplicationLauncher implements
AdapterView.OnItemClickListener {
@Override
public void onItemClick(AdapterView parent, View v, int position,
long id) {
ApplicationInfo app = (ApplicationInfo) parent
.getItemAtPosition(position);
startActivity(app.intent);
}
}
// //////////////////////////////////////////////
public boolean onKeyDown(int k, KeyEvent ev) {
return false;
}
public void onBackPressed() {
Intent intent = new Intent();
intent.setAction(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME)
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
// finish();
}
}
The second fragment is used to view a gridview of file is given by the code below:
public class MatFragment extends Fragment {
private GridViewAjoutFile adapter;
private GridViewAjoutFile ajout = new GridViewAjoutFile();
public static boolean continuer = false;
public static GridviewAdapter mAdapter ;
public static ArrayList<String> listCountry = new ArrayList<String>();
public static ArrayList<Integer> listFlag = new ArrayList<Integer>();
private ArrayList<String> intentType;
private GridView gridView;
private String mStackLevel = " ";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final ArrayList<String> profilTabShortCut;
View view = inflater.inflate(R.layout.maindoc,
container, false);
if (savedInstanceState != null) {
mStackLevel = savedInstanceState.getString("level");
}
prepareList();
mAdapter = new GridviewAdapter(getActivity(),listCountry, listFlag);
//mAdapter.setFile(listCountry , listFlag);
gridView = (GridView) view.findViewById(R.id.gridView2);
//gridView.setAdapter(null);
gridView.setAdapter(mAdapter);
// Implement On Item click listener
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position,
long arg3) { SetIntentType(SessionChoose.listofUrl.get(position),intentType.get(position));
}
});
return view;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putString("level", listCountry.toString());
}
@Override
public void onResume() {
Log.e("DEBUG", "onResume of LoginFragment");
listCountry = removeDuplicate(listCountry);
//listFlag = removeDuplicate1(listFlag);
super.onResume();
}
public static ArrayList<String> removeDuplicate(ArrayList<String> arlList) {
HashSet h = new HashSet(arlList);
arlList.clear();
arlList.addAll(h);
return arlList;
}
public static ArrayList<Integer> removeDuplicate1(ArrayList<Integer> arlList) {
HashSet h = new HashSet(arlList);
arlList.clear();
arlList.addAll(h);
return arlList;
}
public Intent SetIntentType(String url, String intenttype ){
Intent intent = new Intent();
intent.setAction(android.content.Intent.ACTION_VIEW);
return null;
}
public void prepareList()
{ intentType = new ArrayList<String>();
listCountry.clear();
listFlag.clear();
if(SessionChoose.listofDoc.size()>0){
for(int i = 0; i< SessionChoose.listofDoc.size() ; i++){
listCountry.add(SessionChoose.listofDoc.get(i));
String filenameArray[] = SessionChoose.listofDoc.get(i).split("\\.");
String extension = filenameArray[filenameArray.length-1];
}
@Override
public void setUserVisibleHint(boolean isVisibleToUser)
{
super.setUserVisibleHint(isVisibleToUser);
if (isVisibleToUser) {
}
}
private class ApplicationsIntentReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
// appManager.loadApplications(false);
// Intent inte = new Intent(getActivity(),LauncherGridActivity.class);
//startActivity(inte);
}
}
}
回答1:
You can use -
@Override
public void setUserVisibleHint(boolean isVisibleToUser)
{
super.setUserVisibleHint(isVisibleToUser);
if (isVisibleToUser) {
}
}
来源：https://stackoverflow.com/questions/21601578/how-to-remove-fragment-when-i-rotate-my-tablet