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ArrayAdapter with Json Parsing

i'm doing a system of news feed, so, i've a difficulty for adapter my ArrayAdapter insert value into ListView, with: "username, name, picture, content and others values" i'm newbie in Android Studio.
Searching the internet I found this function
HashMap<String,String> persons = new HashMap<String,String>();
persons.put(TAG_ID,id);
persons.put(TAG_NAME,name);
persons.put(TAG_ADD,address);
personList.add(persons);
}
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, personList, R.layout.list_item,
new String[]{TAG_ID,TAG_NAME,TAG_ADD},
new int[]{R.id.id, R.id.name, R.id.address}
);
list.setAdapter(adapter);
But, i use ArrayList and ArrayAdapter:
ArrayList<Post> postList =
new JsonConverter<Post>().toArrayList(s, Post.class);
ArrayList<String> postador = new ArrayList<String>();
for(Post value: postList){
postador.add(value.id_postador);
postador.add(value.post_legenda);
if(value.post_foto != null) {
postador.add(value.post_foto);
}
postador.add(value.post_data);
postador.add(value.curtidas);
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
MainActivity.this,
android.R.layout.simple_list_item_1, postador
);
lvPost.setAdapter(adapter);
I tried it, but no success.
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
MainActivity.this,
R.layout.list_item, postador, new String[]{TAG_ID,TAG_NAME,TAG_ADD},
new int[]{R.id.id, R.id.name, R.id.address}
);
There a method convert ListAdapter in ArrayAdapter or adapter my ArrayAdapter for ListAdapter?

If you are a newbie to Android, I would like to recommend few things to you.
1). Start Using RecyclerView from the very beginning instead of ListView. It is more advanced, flexible and efficient version of ListView. You can find a sample demo for the RecyclerView here and here
2). If you still want to use ListView. Then you further have two options, either to use BaseAdapter or ArrayAdapter.
a). Base Adapter as the name suggests, is a base class for all the adapters. If you need more flexibility, you can go with it. You can find the demo sample here and here
b). On the other hand, ArrayAdapter is a concrete BaseAdapter that is backed by an array of arbitrary objects. By default this class expects that the provided resource id references a single TextView.If you want to use a more complex layout, use the constructors that also takes a field id. That field id should reference a TextView in the larger layout resource.To use something other than TextViews (like in your case) for the array display, for instance, ImageViews, or to have some of data besides toString() results fill the views, override getView(int, View, ViewGroup) to return the type of view you want. You can find the demo sample here and here.
Hope it will help you in future and also I suppose you will get answer to your question in the specified demo samples. Thanks and have a good day.. :)

Migrating from a single dropdown list spinner to a dependant spinner using mySQL data

I have one spinner that populates with my SQL data. This works well. I now want to make it into a dependant spinner where the spinner I already have becomes the second or dependant spinner. I have added another spinner in my MainActivity.java. and it sucessfully retrieves the required mySQL data
#Override
protected void onPostExecute(Void args) {
// Locate spinner1 in activity_main.xml
Spinner spinner1 = (Spinner) findViewById(R.id.spinner1);
// Spinner adapter
List<String> typesofjobsunique = new ArrayList<>(new LinkedHashSet<>(typesofjobs));
spinner1.setAdapter(new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_spinner_dropdown_item, typesofjobsunique));
Collections.sort(typesofjobsunique);
// Locate my spinner in activity_main.xml
Spinner mySpinner = (Spinner) findViewById(R.id.my_spinner);
// Spinner adapter
mySpinner
.setAdapter(new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_spinner_dropdown_item,
worldlist));
Collections.sort(worldlist);
What is the simplest coding approach to migrate from a single to a dependant spinner given the data retrieval itself works well for both spinners and I just want to make it dependant from the current independant format so
spinner1 typesofjobsunique only displays the
mySpinner worldlist
spinner choices from mySQL corresponding to that particular typeofjobunique.
Most of the questions on here relating to dependant spinners, are where the data is in strings.xml which is not very helpful with remote data.
I'm assuming I will need to split my one adapter into two separate adapters, but I am unclear how to proceeed.

From the way that Spinners work, if you want to implement dependence between them, you will need to use the current selection of one (spinner1) as the key for the list source of the other (mySpinner). You should implement an AdapterView.OnItemSelectedListener on spinner1 as recommended in the Spinner guide and set the list in mySpinner. See code below:
// Locate spinner1 in activity_main.xml
Spinner spinner1 = (Spinner) findViewById(R.id.spinner1);
// Locate mySpinner in activity_main.xml
Spinner mySpinner = (Spinner) findViewById(R.id.my_spinner);
// Spinner adapter
List<String> typesofjobsunique = new ArrayList<>(new LinkedHashSet<>(typesofjobs));
spinner1.setAdapter(new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_spinner_dropdown_item, typesofjobsunique));
spinner1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
// **EDIT**
List<String> myWorldList = getWorldListForItem(parent.getItemAtPosition(pos));
Collections.sort(myWorldList);
mySpinner
.setAdapter(new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_spinner_dropdown_item,
myWorldList));
}
public void onNothingSelected(AdapterView<?> parent) {
// Another interface callback
}
});
Collections.sort(typesofjobsunique);
The implementation for getWorldListForItem() should query your database in the desired way. A hash table could also be used.
Hope that this is useful.
EDIT
Based on your comments, the implementation for getWordListForItem() would look something like this:
List<String> getWordListForItem(String s) {
String json = queryMySQLDatabase(s);
List<String> results = parseJSONintoList(json);
return results;
}
Also, the AdapterView.getItemAtPosition(int pos) function returns a Java object of the type passed into the ArrayAdapter (which is a String in this case). Therefore getWordListForItem() takes a String argument.
As for the "Cannot resolve contructor ArrayAdaptor" error, please check the spelling (it's supposed to be ArrayAdapter not ArrayAdaptor). See ArrayAdapter documentation for more details... I've also fixed my implementation above to sort the list properly.

Retrieving ListView to Adaptor across classes

I am trying to add items to a ListView/Adapter from my MainActivity and use it across ListHelper.
I have it declared in Registrant.
public static List<Registrant> searchList = new ArrayList<Registrant>();
And then I add to it from MainActivity..
Registrant.searchList.add(registrant);
Then I try to retrieve this into a listview from the ListHelper.
ListView listView = (ListView) findViewById(R.id.list);
listView.setAdapter(adapter);
adapter = new CustomListAdapter(this, Registrant.searchList);
adapter.notifyDataSetChanged();
But no luck, it is a blank screen?
Any ideas would be helpful.. thank you!

Instead of creating object of CustomListAdapter class for updating data in ListView data-source. create a method in CustomListAdapter class for adding data in List which is used by Adapter as data-source :
In CustomListAdapter class add following method:
public void addItems(){
arrList.addAll(Registrant.searchList);
this.notifyDataSetChanged();
}
Now call addItems method when want to update data in ListView:
listView.setAdapter(adapter);
adapter.addItems();

build list from array and allow list to be clickable

I'm trying to build and Android app:
How can I build a list on screen from an array and have the list be clickable?
with a value of the name to be able to use later stored in a String.
What I have now.
String game_list[] = {"game_0","game_2","game_3","game_3","game_4","game_5"};
for(int i=0; i<game_list.length; i++){
myText = myText + game_list[i] +"\n";
}
myTextView.setText("");
myTextView.append(myText);

Also you can use a spinner and adapter
ArrayAdapter<String> adapter = new ArrayAdapter<String>(context, android.R.layout.simple_spinner_item, game_list); adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(adapter);

Here's a super simple example that I have used: http://www.javacodegeeks.com/2013/06/android-listview-tutorial-and-basic-example.html.
You basically need to make a listview object and add it to whatever view you happen to be using. Then you add "extends ListActivity" to the activity and add your list to the listactivity like so:
ArrayAdapter<String> directoryList = new ArrayAdapter<String>(this,R.layout.file_row, this.directoryEntries);
ListView fileList = (ListView) findViewById(android.R.id.list);
fileList.setAdapter(directoryList);
Call:
protected void onListItemClick(ListView l, View v, int position, long id)
to associate actions with your listview elements

You can build that with ListView control in android and here very good tutorial about it to get more understand how to build it with the array or from any other data source like from database
http://www.vogella.com/tutorials/AndroidListView/article.html
feed be back in any thing not obvious for you

How to get TextView from ListView item?

I have following code for making ListView:
SimpleAdapter adapter=new SimpleAdapter(this, DictionaryDbWrapper.getInstance().getAllWords(),
android.R.layout.simple_list_item_2, new String[]{DictionaryDbHelper.WORD, DictionaryDbHelper.CATEGORY},
new int[]{android.R.id.text1, android.R.id.text2});
mList.setAdapter(adapter);
It works and show me elements, all correct. Also I have OnItemClickListener with following code for clicking by items:
View view=mList.getSelectedView();
if (view==null) {
Toast.makeText(UpdatingWordActivity.this, "1", Toast.LENGTH_LONG).show();
}
But mList.getSelectedView() returns me null also. Why?
UPDATE: why does this cast throw exception:
View v=(View)mList.getItemAtPosition(0);

The call to getSelectedView() is for when you use radio buttons with the listview. See CHOICE_MODE_SINGLE. getItemAtPosition() just calls getItem(position) on the underlying adapter; in your case it's a SimpleAdapter. That casting throws an exception because SimpleAdapter.getItem() isn't returning a view, it's returning (I believe) the Map of data that is at the given position in the adapter. Other adapters return other things for the getItem() method. For instance, the CursorAdapter returns a cursor.
See the answer above for the answer to the first question

Listview OnItemClickListener has View v as parameter, you need to use this parameter to get text.
Here is Android tutorial on this topic .