Develop Reference

Add Correct answers to Alert Dialog

Please help. I want to display the correct answers in an alert dialog, if i type "rightAnswers" inside "builder.setMessage("Answer : " + rightAnswers);" an alert show "Answer: 1". Number 1 instead of the correct answer. please teach me what to put to be able to display the correct answer. thank you so much.
public class thisactivity extends AppCompatActivity {
Button choice1,choice2;
ImageView images;
List<Model> list;
int turn = 1;
int rightAnswers = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_thisactivity);
images = (ImageView) findViewById(R.id.images);
choice1 = (Button) findViewById(R.id.choice1);
choice2 = (Button) findViewById(R.id.choice2);
list = new ArrayList<>();
for (int i = 0; i < new Signsdatabase().answers.length; i++) {
list.add(new Model(new Signsdatabase().answers[i], new
Signsdatabase().signs[i]));
}
newQuestion(turn);
choice1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String alertTitle;
if(choice1.getText().toString().equalsIgnoreCase(list.get(turn -
1).getName())) {
rightAnswers = rightAnswers + 1;
alertTitle = "Correct!";
if (turn < list.size()) {
turn++;
newQuestion(turn);
} else {
Toast.makeText(thisactivity.this, "You have completed the Quiz!", Toast.LENGTH_SHORT).show();
}
}
AlertDialog.Builder builder = new
AlertDialog.Builder(thisactivity.this)
builder.setTitle(alertTitle);
builder.setMessage("Answer : " + **CORRECT ANSWERS**); <---I WANT TO DISPLAY THE CORRECT ANSWER HERE BUT I DO NOT KNOW HOW------->
builder.setIcon(R.drawable.pic);
builder.setPositiveButton("OK", new
DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int i) {
}
});
}
});
choice2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (choice2.getText().toString().equalsIgnoreCase(list.get(turn - 1).getName())) {
rightAnswers = rightAnswers + 1;
if (turn < list.size()) {
turn++;
newQuestion(turn);
} else {
Toast.makeText(thisactivity.this, "You have completed the Quiz!", Toast.LENGTH_SHORT).show();
getResults();
}
} else {
}
AlertDialog.Builder builder = new
AlertDialog.Builder(Roadsigns.this)
builder.setTitle(alertTitle);
builder.setMessage("Answer : " + **CORRECT ANSWERS**); <---I WANT TO DISPLAY THE CORRECT ANSWER HERE BUT I DO NOT KNOW HOW------->
builder.setIcon(R.drawable.pic);
builder.setPositiveButton("OK", new
DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int i) {
}
});
builder.setCancelable(false);
builder.show();
}
});
}
............
And this is my Signsdatabase
public class Signsdatabase {
Integer[] signs ={
R.drawable.q1,
R.drawable.q2,
R.drawable.q3,
};
String[] answers = {
"Ans1",
"Ans2",
"Ans3",
};
}

Make this change in alter dialog.
make Signsdatabase object or make static in answer array.
builder.setMessage("Answer : " + Signsdatabase.answers[rightAnswers]);

You display the index of the right answer, you need to get the item from the list at the corresponding position:
builder.setMessage("Answer : " + signsdatabase.answers[rightAnswers]);
builder.setMessage("Answer : " + list[rightAnswers]);// it also check.
And you also need to initialize signsdatabase before
signsdatabase = new Signsdatabase();

Suppose you have the correct index of the answer You can do one of the following :
One
Create an object of SignsDatabase :
signsDb = new Signsdatabase();
With index i of correct answer :
builder.setMessage("Answer : "+ signDb.answers[i];
Two
If you do not want to create an instance of SignDatabase, you can declare the answers as static variable so :
public class SignDatabase{
... //some code here
public static String[] answers = ["Abc","xyz"];
}
Then access it directly by calling :
builder.setMessage(SignDatabase.answers[i]);

adding functionality to back key in android to go to previous folder location in a file manager

I know this has been discussed so many times but really I am not able to figure it out. I am so sorry for asking it again. I am making android file manager. I am showing the files and folders in a listview. I want to add functionality to "back" key. Currently pressing back key at any time results in exit from the app. I want it to go to the previous folder if any or otherwise exit the app. I was trying onBackPressed() method but couldn't figure out what should be written there. Please help me.
Here is my MainActivity.java file :
public class MainActivity extends ListActivity {
private ArrayList<String> item = null;
private ArrayList<String> path = null;
private String root="/";
private TextView myPath;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); /**super keyword in java is a reference variable that
is used to refer immediate parent class object. */
setContentView(R.layout.activity_main);
myPath = (TextView)findViewById(R.id.path); /* storing the current path*/
getDir(root);
}
private void getDir(String dirPath)
{
myPath.setText("Location: " + dirPath);
item = new ArrayList<String>();
path = new ArrayList<String>();
File f = new File(dirPath);
File[] files = f.listFiles(); /** files is an array of all the files in a directory. */
if(!dirPath.equals(root))
{
item.add(root);
path.add(root);
item.add("../");
path.add(f.getParent());
}
for(int i=0; i < files.length; i++)
{
File file = files[i];
path.add(file.getPath());
if(file.isDirectory())
item.add(file.getName() + "/");
else
item.add(file.getName());
}
ArrayAdapter<String> fileList = new ArrayAdapter<String>(this, R.layout.row, item);
setListAdapter(fileList);
}
protected void onListItemClick(ListView l, View v, int position, long id) {
File file = new File(path.get(position));
if (file.isDirectory())
{
if(file.canRead())
getDir(path.get(position));
else
{
new AlertDialog.Builder(this)
.setIcon(R.drawable.icon)
.setTitle("[" + file.getName() + "] folder can't be read!")
.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
}).show();
}
}
else
{
new AlertDialog.Builder(this)
.setIcon(R.drawable.icon)
.setTitle("[" + file.getName() + "]")
.setPositiveButton("OK",
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
}).show();
}
}

you can try this:
#Override
protected void onBackPressed(){
//super.onBackPressed(); //remove it if you want control
String previousDir = "build your previous dir here";
if (previousDir != null){ //if deferent root path
Intent activityDir = new Intent(this, MainActivity.class);
activityDir.putExtra("DIR_PATH", previousDir);
startActivity(activityDir);
}//end if
finish(); //close this screen to show new screen above with new path
}
Note: you have to edit onCreate(....) as bellow code:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); /**super keyword in java is a reference variable that
is used to refer immediate parent class object. */
setContentView(R.layout.activity_main);
myPath = (TextView)findViewById(R.id.path); /* storing the current path*/
if(getIntent() != null){
root = getIntent().getStringExtra("DIR_PATH", root); //if is null then get root
}
getDir(root);
}

ArrayIndexOutOfBoundsException / passing arraylist from alertdialog to activity

I have an alertdialog with multiple choices, I store the user's choices on an ArrayList of strings, and I want to pass the stored arraylist to the host activity (I will use the array's elements to query my database)..
When i run my app, i get an ArrayIndexOutOfBoundsException (may be the index is -1..), I'm not sure if it's the loop, or if i did not pass the arraylist correctly from the alertdialog...
can you guys take a look ? here is my function :
public void onOkay(ArrayList<String> selected) {
StringBuilder stringBuilder = new StringBuilder();
if (selected.size() != 0) {
for (int i = 0; i < selected.size(); i++) {
String categories = selected_items_array[selected.indexOf(i)];
stringBuilder = stringBuilder.append(" " + categories);
}
Toast.makeText(this, "You have selected: "
+ stringBuilder.toString(), Toast.LENGTH_SHORT).show();
}
}
logcat :
java.lang.ArrayIndexOutOfBoundsException: length=6; index=-1
at com.hichamridouane.smartshop.MainActivity.onOkay(MainActivity.java:164)
at com.hichamridouane.smartshop.TimelineSettings$2.onClick(TimelineSettings.java:71)
here is my dialogfragment class.
and here is my host activity.(as I said, i'm not sure if i'm passing correctly the arraylist to the host activity)
thanks !

It looks really strange to me, especially in
String categories = selected_items_array[selected.indexOf(i)];
From JavaDocs about indexOf
Returns the index of the first occurrence of the specified element
in this list, or -1 if this list does not contain the element.
More formally, returns the lowest index <tt>i</tt> such that
<tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>,
or -1 if there is no such index.
So, you try to find element in your selected_items_array (not correct name in Java)
in first iteration i == 0, selected_items_array have no such element => indexOf return -1. Array can't have element with index = -1, it starts from 0. So you have your ArrayIndexOutOfBoundsException

Problem solved. Had to use Arraylists of integers in my activity and my dialogfragment.
here is what i did in my DialogFragment class:
public class TimelineSettings extends DialogFragment {
ArrayList<Integer> selected_categories = new ArrayList<Integer>();
boolean[] itemsChecked = {false, false, false, false, false, false};
// this interface to communicate with the host activity.
public interface dialoglistener {
public void onOkay(ArrayList<Integer> selected);
public void onCancel();
}
dialoglistener mlistener;
//this function is to instantiate the dialoglistener
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mlistener = (dialoglistener) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString()
+ " must implement dialogListener");
}
}
My multichoice dialog :
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
for(int i=0;i<itemsChecked.length;i++){
if(selected_categories.contains((String)String.valueOf(i)))
itemsChecked[i]=true;
}
// Set the dialog title
builder.setTitle("Choisissez vos paramètres")
.setMultiChoiceItems(R.array.categories, itemsChecked,
new DialogInterface.OnMultiChoiceClickListener() {
#Override
public void onClick(DialogInterface dialog, int indexselected,
boolean isChecked) {
if (isChecked) {
// If the user checked the item, add it to the selected items
if(!selected_categories.contains(indexselected)){
selected_categories.add(indexselected);
itemsChecked[indexselected]=true;
}
} else if (selected_categories.contains(indexselected)) {
// Else, if the item is already in the array, remove it
selected_categories.remove(indexselected);
itemsChecked[indexselected]=false;
}
}
})
// Set the action buttons
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
mlistener.onOkay(selected_categories);
}
})
.setNegativeButton("Annuler", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
mlistener.onCancel();
}
});
return builder.create();
}
On my host activity, I implemented the fragment's interface :
#Override
public void onCreate(Bundle savedInstanceState) {
/* some fancy stuff */
Resources res = getResources();
selectedArray = res.getStringArray(R.array.categories);
}
Getting the selected items (and show them on a toast, just for testing) :
#Override
public void onOkay(ArrayList<Integer> selected) {
StringBuilder stringBuilder = new StringBuilder();
if (selected.size() != 0) {
for (int i = 0; i < selected.size(); i++) {
String categories = selectedArray[selected.get(i)];
stringBuilder = stringBuilder.append(" " + categories);
}
Toast.makeText(this, "You have selected: "
+ stringBuilder.toString(), Toast.LENGTH_SHORT).show();
}
}

How to sort files using datetimestamp

I am capturing images, then storing into SD Card and showing in a List, but here i need a small change, still i am getting old on top and latest at bottom, so now i want to show latest picture on the top on the basis of datetimestamp using as a part of file name.
UploadActivity.java code:-
String fileName;
static List <String> ImageList;
/*** Get Images from SDCard ***/
ImageList = getSD();
// ListView and imageAdapter
lstView = (ListView) findViewById(R.id.listView1);
lstView.setAdapter(new ImageAdapter(this));
}
public static List <String> getSD()
{
List <String> it = new ArrayList <String>();
String string = "/mnt/sdcard/Pictures/SamCam/";
f = new File (string+ CameraLauncherActivity.folder+ "/");
files = f.listFiles ();
for (int i = 0; i < files.length; i++)
{
file = files[i];
Log.d("Count",file.getPath());
it.add (file.getPath());
}
return it;
}
public class ImageAdapter extends BaseAdapter
{
private Context context;
public ImageAdapter(Context c)
{
// TODO Auto-generated method stub
context = c;
}
Note: I am using date/timestamp while storing my images into SD Card.
so finally it looks like this:
AU_20140328163947_1_4_X-1-4-006.jpg
and still files listing in below format, like below:
AU_20140328163947_1_4_X-1-4-006.jpg
AU_20140328163948_1_4_X-1-4-007.jpg
AU_20140328163949_1_4_X-1-4-008.jpg
but i want to list files in below format:-
AU_20140328163949_1_4_X-1-4-008.jpg
AU_20140328163948_1_4_X-1-4-007.jpg
AU_20140328163947_1_4_X-1-4-006.jpg
Code to Delete Image in a List:--
// btnDelete
final ImageButton btnDelete = (ImageButton) convertView.findViewById(R.id.btnDelete);
btnDelete.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context);
// set title
alertDialogBuilder.setTitle("Delete Image");
// Setting Icon to Dialog
alertDialogBuilder.setIcon(R.drawable.ic_launcher);
// set dialog message
alertDialogBuilder
.setMessage("Are you sure you want to delete this image?")
.setCancelable(false)
.setPositiveButton("Yes",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, close
// current activity
// to get fileName
fileName = ImageList.get(position).toString().substring(strPath.lastIndexOf('/')+1, strPath.length());
// to get SD card path (Folders+fileName)
String fileToDelete = Environment.getExternalStorageDirectory().getPath() +"/Pictures/SamCam/" + CameraLauncherActivity.folder+ "/" + fileName;
Log.d("FileToDelete", fileToDelete);
File myFile = new File(fileToDelete);
// if image exists
if(myFile.exists())
// delete image
myFile.delete();
// get position and delete
ImageList.remove(position);
// to refresh the view
((BaseAdapter) lstView.getAdapter()).notifyDataSetChanged();
dialog.cancel();
}
})
.setNegativeButton("Cancel",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, just close
// the dialog box and do nothing
dialog.cancel();
}
});
// create alert dialog
AlertDialog alertDialog = alertDialogBuilder.create();
// show it
alertDialog.show();
// TODO Auto-generated method stub
}
});
return convertView;
}
}

If you getting data in reverse order than you can use reverse loop.
Try below loop
for (int i = files.length-1; i >= 0; i--)
{
file = files[i];
Log.d("Count",file.getPath());
it.add (file.getPath());
}
instead of
for (int i = 0; i < files.length; i++)
{
file = files[i];
Log.d("Count",file.getPath());
it.add (file.getPath());
}
or sort data with particular field
Sort array data before using in for loop and use same loop..
Arrays.sort(files, new Comparator<Object>()
{
public int compare(Object o1, Object o2) {
if (((File)o1).lastModified() > ((File)o2).lastModified()) {
return -1;
} else if (((File)o1).lastModified() < ((File)o2).lastModified()) {
return +1;
} else {
return 0;
}
}
});
for (int i = 0; i < files.length; i++)
{
file = files[i];
Log.d("Count",file.getPath());
it.add (file.getPath());
}

Use MediaStore ContentProvider for this job
Save the image using MediaStore using this method
And you can query the image using this method
Set the order by as MediaStore.Images.Media.DATE_TAKEN

You can use the Collections.sort method in your list adapter to sort the values according to the image file name like:
Collections.sort(ImageList, new Comparator<String>() {
int compare(String obj1, String obj2) {
return obj1.compareTo(obj2);
}
});
compareTo method and also compareToIgnoreCase method, use wichever you think is appropriate, and also, you can experiment with obj1 and obj2, that is, you could swap the condition to:
return obj2.compareTo(obj1);
That way your list will be sorted. Hope that helps!
EDIT:
Since you know that the format is _ and then -.jpg, what you can do is in the comparator split the value from - like:
Collections.sort(ImageList, new Comparator<String>() {
int compare(String obj1, String obj2) {
String[] obj1Arr = obj1.split(-);
String[] obj2Arr = obj2.split(-);
obj1Arr = obj1Arr[1].split("."); // to just get the counter value
obj2Arr = obj2Arr[1].split(".");
return obj1Arr[0].compareTo(obj2Arr[0]);
}
});

How to clear all items in a ListView while using List Adapter onTextChange?

I have been trying to find answers, but it has been hard to find a solution that works.
I tried setting the adapter to null, clearing the actual list but neither seems to work.
I am using a ListView with a ListAdapter and am trying to make it clear on a change of search Text when text is changed.
list.clear(); works but it does not occur on text change.
Here is my code:
private EditText search_input;
private Button search_button;
// progress bar for search results
private ProgressDialog search_loading;
private ListView wordSearchList;
private ListAdapter adapter;
// no result layout
private LinearLayout no_res;
// create list for adapter
ArrayList<HashMap<String, String>> list;
// database helper
private DatabaseHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dictionary_search);
search_input = (EditText) findViewById(R.id.search_dictionary);
search_button = (Button) findViewById(R.id.search_button);
search_button.setOnClickListener(this);
// linear layout for no results
no_res = (LinearLayout) findViewById(R.id.search_result_ll);
// create hashmap list
list = new ArrayList<HashMap<String, String>>();
// remove views if they exist
search_input.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence s, int start, int before,
int count) {
// REMOVE LIST VIEW AND ADAPTER
// list.clear();
if (no_res.getChildCount() > 0) {
no_res.removeAllViews();
}
}
#Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
#Override
public void afterTextChanged(Editable s) {
}
});
}
#Override
public void onClick(View v) {
if (v == search_button) {
// clear list for fresh start
list.clear();
no_res.removeAllViews();
// validate input and that something was entered
if (search_input.getText().toString().length() < 1) {
// missing required info (null was this but lets see)
Toast.makeText(getApplicationContext(),
"Please search for something!", Toast.LENGTH_LONG)
.show();
} else {
String search_data;
search_data = search_input.getText().toString();
// remove any current views on search again
// REMOVE THE LIST VIEW
// execute the query search
List<DatabaseWordsFTS> search_results = db
.getSingleWordSearch(search_data);
// if no search results returned
if (search_results.size() <= 0) {
TextView no_results_tv = new TextView(this);
no_results_tv.setText("No results found.");
no_res.addView(no_results_tv);
}
// setup listview
wordSearchList = (ListView) findViewById(R.id.wordSearchList);
for (DatabaseWordsFTS word_found : search_results) {
// have to create hashmap in loop
HashMap<String, String> map = new HashMap<String, String>();
// convert d id to long
Integer dictionary_id_convert = (int) (long) word_found._dictionaryId;
// extract dictionary from d-id - since it is not a list and
// just a variable
DatabaseDictionary dictionary_found = db
.getDictionary(dictionary_id_convert);
// extract languages to send below
Integer dln_1 = (int) dictionary_found._language1Id;
Integer dln_2 = (int) dictionary_found._language2Id;
Integer dln_3 = (int) dictionary_found._language3Id;
Integer dln_4 = (int) dictionary_found._language4Id;
// get languages for the words based on ids passed in
List<DatabaseLanguages> LanguagesForD = db
.getAllLanguagesWithId(dln_1, dln_2, dln_3, dln_4);
// add name to hashmap and rest of the data as strings
map.put("w_1", word_found.get_word1_fts());
map.put("l_1", LanguagesForD.get(0)._language_name);
map.put("d_id", String.valueOf(dictionary_id_convert));
map.put("w_id", String.valueOf(word_found.get_id()));
if (word_found.get_word2_fts() != null) {
map.put("w_2", word_found.get_word2_fts());
map.put("l_2", LanguagesForD.get(1)._language_name);
}
if (word_found.get_word3_fts() != null) {
map.put("w_3", word_found.get_word3_fts());
map.put("l_3", LanguagesForD.get(2)._language_name);
}
if (word_found.get_word4_fts() != null) {
map.put("w_4", word_found.get_word4_fts());
map.put("l_4", LanguagesForD.get(3)._language_name);
}
list.add(map);
// used to dismiss progress bar for searching
search_loading.dismiss();
}
String[] from = { "w_1", "w_2", "w_3", "w_4" }; // , "word3",
// "word4"
int[] to = { R.id.textName, R.id.textLanguage };
adapter = new SimpleAdapter(this, list,
R.layout.dictionary_row, from, to);
wordSearchList.setAdapter(adapter);
wordSearchList
.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent,
View view, int position, long id) {
// ListView Clicked item index
int itemPosition = position;
// ListView Clicked item value
HashMap itemValue = (HashMap) wordSearchList
.getItemAtPosition(position);
String w_id = (String) itemValue.get("w_id");
String d_id = (String) itemValue.get("d_id");
String l_1 = (String) itemValue.get("l_1");
String l_2 = (String) itemValue.get("l_2");
String l_3 = (String) itemValue.get("l_3");
String l_4 = (String) itemValue.get("l_4");
String w_1 = (String) itemValue.get("w_1");
String w_2 = (String) itemValue.get("w_2");
String w_3 = (String) itemValue.get("w_3");
String w_4 = (String) itemValue.get("w_4");
// Show Alert
Toast.makeText(
getApplicationContext(),
"Position :" + itemPosition
+ " ListItem : " + w_id,
Toast.LENGTH_LONG).show();
// creating bundle
Bundle d_data = new Bundle();
// add to bundle
d_data.putString("w_id", w_id);
d_data.putString("wd_id", d_id);
d_data.putString("w_1", w_1);
d_data.putString("l_1", l_1);
// get tags only if it exists
if (w_2 != null) {
d_data.putString("w_2", w_2);
d_data.putString("l_2", l_2);
}
if (w_3 != null) {
d_data.putString("w_3", w_3);
d_data.putString("l_3", l_3);
}
if (w_4 != null) {
d_data.putString("w_4", w_4);
d_data.putString("l_4", l_4);
}
// start new intent based on the tag -
Intent single_word_view = new Intent(
DictionaryWordSearch.this,
DictionarySingleWordView.class);
// call extras
single_word_view.putExtras(d_data);
// new_dictionary_view.putExtra("d_id",
// WhatAmISupposeToPassInHere);
startActivity(single_word_view);
}
});
}
EDIT: (Below worked for me)
Changed ListAdapter to SimpleAdapter
if(adapter != null){list.clear(); adapter.notifyDataSetChanged();}
Added the above code in onTextChange

Look if you want the TextView with no result you can implement this code
listView.setEmptyView(emptyView)
and pass your TextView to this method ,
for clearing the ListView you can clear your collection and call notifyChangeDataSet or set adapter with null try both and feed me back