this is my very first question so go easy on me :)
I am new to android, and I am trying to make a simple list. On the first Activity the user can enter data, which should display as a list on the second Activity.
I am using Intents to pass the data from one Activity to another, but I know I am missing something crucial in my ClassB Activity as nothing displays.
Here is my main code:
public class ClassA extends AppCompatActivity {
EditText note;
Button saveNoteB, goToNotesB;
public final static String EXTRA_NOTE = "com.lisa.currys.userlistarray.note";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
saveNoteB = (Button) findViewById(R.id.saveNote);
saveNoteB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(ClassA.this, ClassB.class);
note = (EditText) findViewById(R.id.note);
String userInput = note.getText().toString();
ArrayList<String> arr = new ArrayList<String>();
arr.add(userInput);
i.putStringArrayListExtra("note", arr);
startActivity(i);
}
});
and for my second activity:
public class ClassB extends AppCompatActivity {
public static android.widget.ListView displayNotes;
ArrayList<String> arr = new ArrayList<String>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
arr = getIntent().getExtras().getStringArrayList(ClassA.EXTRA_NOTE);
displayNotes = (ListView)findViewById(R.id.listView);
Intent i = getIntent();
arr = i.getStringArrayListExtra("note");
ArrayAdapter<String> adapter = new ArrayAdapter<String>(ClassB.this, android.R.layout.simple_list_item_1);
displayNotes.setAdapter(adapter);
}
}
Any pointers or advice would be most welcome.
Thank you.
You are never actually adding the elements in arr to the ArrayAdapter. Use the three argument constructor for ArrayAdapter like below which will add the elements:
ArrayAdapter<String> adapter =
new ArrayAdapter<String>(ClassB.this, android.R.layout.simple_list_item_1, arr);
In ClassA try this:
i.putStringArrayListExtra(EXTRA_NOTE, arr);
or in ClassB try this:
arr = getIntent().getExtras().getStringArrayList("note");
You have to use the same key to set and get the values.
By the way, why are you assign values to "arr" two times?
Try this
ArrayAdapter<String> adapter = new ArrayAdapter<String>(ClassB.this, android.R.layout.simple_list_item_1);
Above statement you are pass the context and layout in which your data
display but you are not give the data which is store
in your **arr** arraylist so you not show anything.
replace this statement to
ArrayAdapter<String> adapter =
new ArrayAdapter<String>(ClassB.this, android.R.layout.simple_list_item_1, arr);
Related
so lets just to the point, here is my code, and when i try to use Edittext and an button for saving data to listView, it works fine and all item show up on list view, but with a way that looks like in below, its only show one...
public class History extends Activity {
ListView show;
Button Home, toMap, Next;
EditText listTextMaker;
ArrayList<String> addArray = new ArrayList<String>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_history);
Home = findViewById(R.id.homeBtn);
toMap = findViewById(R.id.backBtn);
Next = findViewById(R.id.nextBtn);
show = findViewById(R.id.textHistory);
listTextMaker = findViewById(R.id.text);
listTextMaker.setVisibility(View.INVISIBLE);
ConstructorBuilder();
}
public void Constructor(){
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
String dataHistory = prefs.getString("History", null );
addArray.add(dataHistory);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(History.this, android.R.layout.simple_expandable_list_item_1, addArray);
show.setAdapter(adapter);
}
public void ConstructorBuilder(){
Constractor();
}
}
you are adding only one data on your list:
String dataHistory = prefs.getString("History", null );
addArray.add(dataHistory);
If you want more than one data then just use below code:
String dataHistory = prefs.getString("History", null );
addArray.add(dataHistory);
addArray.add(dataHistory);
addArray.add(dataHistory);
addArray.add(dataHistory);
addArray.add(dataHistory);
How can i get user inputs from one activity and populate the listView with user data in another activity. I am able to get user input and populate the listView in the same activity. but now i want to get user inputs in one form and populate the list in another activity.
the code that i used to populate the listView by getting user input is as follows
public class MainActivity extends ListActivity {
ArrayList<String> list = new ArrayList<String>();
/** Declaring an ArrayAdapter to set items to ListView */
ArrayAdapter<String> adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = (Button) findViewById(R.id.btnAdd);
/** Defining the ArrayAdapter to set items to ListView */
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list);
/** Defining a click event listener for the button "Add" */
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View v) {
EditText edit = (EditText) findViewById(R.id.txtItem);
String name=edit.getText().toString();
list.add(name);
edit.setText("");
adapter.notifyDataSetChanged();
}
};
/** Setting the event listener for the add button */
btn.setOnClickListener(listener);
you can store your user input / data into a local database; that will allow you to access your data anywhere in the app
(recommended since you are dealing with listview).
you can use shared preferences to store data if your data is relatively small.
In your current Activity (activity contains your button), create a new Intent:
String name = "";
name = edit.getText().toString();
Intent i = new Intent(getApplicationContext(), NewActivity.class);
i.putExtra("keyword",name);
startActivity(i);
Then in the NewActivity (activity contains your Listview), retrieve those values:
Bundle extras = getIntent().getExtras();
if (extras != null) {
String name = extras.getString("keyword");
if(name != ""){
// adapter.notifyDataSetChanged();
}
}
It is simple way, hope this help
Declare a public method in second Activity like
SecondActivity.class
public static ArrayList<String> list = new ArrayList<String>();
/** Declaring an ArrayAdapter to set items to ListView */
ArrayAdapter<String> adapter
onCreate()
{
...
;
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list);
listview.setAdapter(adapter);
...
}
public static void ModifyList()
{
adapter.notifyDataSetChanged();
}
FirstActivity.class
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View v) {
EditText edit = (EditText) findViewById(R.id.txtItem);
String name=edit.getText().toString();
SecondActivity.list.add(name);
edit.setText("");
SecondActivity.ModifyList();
}
};
Send your ArrayList like this from FirstActivity :
Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
intent.putStringArrayListExtra("Datalist",list);
startActivity(intent);
In secondActivity Recieve the list using :
Intent i = getIntent();
list = i.getStringArrayListExtra("Datalist");
Then display it in your SecondActivitys listview
i have two activity files in my code, and the first activity file loads the layout search, and the second file loads layout list. I have a textbox in layout search and enter some text. I want to use this text in my second activity file but i can not reach it since it is in the layout search. How can i do this? Here the first activity file, here there is an EditText item called searchedText, and i want to use it in the second activity file.
public class SearchActivity extends Activity{
public EditText searchedText;
public RadioGroup radioGroup;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.search);
}
public void onStart(){
super.onStart();
searchedText = (EditText) findViewById(R.id.searchText);
Button searchinSearchButton = (Button)findViewById(R.id.searchInSearch);
radioGroup = (RadioGroup) findViewById(R.id.radioGroup1);
searchinSearchButton.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
String searched=searchedText.getText().toString();
Intent myIntent = new Intent(v.getContext(),
SearchListActivity.class);
startActivityForResult(myIntent, 1);
}
});
}
}
And here is the second activity file:
public class SearchListActivity extends Activity{
public DatabaseAdapter db;
public ArrayList<String> myList;
public ListView listview;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.list);
db = new DatabaseAdapter(this);
myList = new ArrayList<String>();
getContacts();
// Example of retrieving tweets of the user "mashable" and adding them to
myList
/*
ArrayList<Tweet> tweets= new ArrayList<Tweet>();
tweets.addAll(Twitter.getTimeline("mashable", 10));
for(Tweet t: tweets){
myList.add(t.username + ": " + t.message + " Tweet id: "+ t.id);
}
*/
printList();
}
public void printList(){
listview = (ListView)findViewById(R.id.contactcListView);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, myList);
listview.setAdapter(adapter);
}
public void getContacts() {
db.open();
Cursor c = db.getContactbyName("y");
if (c.moveToFirst()) {
do {
DisplayContact(c);
} while (c.moveToNext());
}
db.close();
}
public void DisplayContact(Cursor c) {
String entry = "";
// if you add another attribute to your table, you need to change 3 into x
for (int i=1; i<5;i++){
entry += c.getString(i) + "\n";
}
myList.add(entry);
}
}
In this second activity file, you can see the getContacts() method. There, i search by Cursor c = db.getContactbyName("y"); but instead of "y", i want to search whatever user enters the texbox, whic is in the 1st activity file called searchedText. How can i do this?
Thanks
Send the text as an extra in your Intent when you start your second activity.
searchinSearchButton.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
String searched=searchedText.getText().toString();
Intent myIntent = new Intent(v.getContext(),
SearchListActivity.class);
myIntent.putExtra("SEARCH_STRING",searched);
startActivityForResult(myIntent, 1);
}
});
And in your onCreate get the extra. You could use Intent.getStringExtra(String name)
In other words:
mySearched = getIntent().getStringExtra("SEARCH_STRING");
Just make sure to see if anything is null before using it.
I have two simple Activities -
Activity1: ListView from an Array
Activity2: EditText for editing the clicked row in Activity1
When I edit the value in Activity2 and returning to Activity1, the ListView doesn't reload the new value.
I want to refresh the ListView when I return from Activity2 or resume Activity1 or something that will update the list.
My code:
static ArrayAdapter<String> dataAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Loading the values to list array
String[][] fulllist = loadArrays();
String[] list = new String[fulllist.length];
for(int i = 0; i<fulllist.length; i++) {
list[i] = fulllist[i][1];
}
// --------------------------------
dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1,
list);
setListAdapter(dataAdapter);
}
#Override
public void onResume() {
super.onResume();
// Loading the values to list array
String[][] fulllist = loadArrays();
String[] list = new String[fulllist.length];
for(int i = 0; i<fulllist.length; i++) {
list[i] = fulllist[i][1];
}
// --------------------------------
dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1,
list);
dataAdapter.notifyDataSetChanged();
}
loadArrays() is just method that converts from SharedPreferences to String Array. Activity2 saves the new data in SharedPreferences and than Activity1 can read it (with the new data).
If I return to the "main activity" (it is not Activity1) and than come back to Activity1 - the new data is shown, but I want this data will be updated when I return from Activity2 immediately.
loadArrays() method: pastebin.com/MHwNC0jK
Thanking you in advance!
On clicking the item in your first Activity, start your second Activity with startActivityForResult()
And then in Second Activity, after entering in EditText, probably there is a button. And in onClick of that button call,
intent.putExtra("edittextvalue", findViewById(R.id.edittext).getText().toString());
setResult(RESULT_OK, intent);
finish();
Now you come back to your first Activity and here you have to implement onActivityResult() callback. You can extract data from that intent's extras and set that respective item in your array and call notifyDataSetChanged().
This is ideally how you should be doing it.
If you want more info on how to use startActivityForResult() try this link - http://manisivapuram.blogspot.in/2011/06/how-to-use-startactivityforresult.html
1) Get reference ListView
mListView = (ListView)findViewById(R.id.auto_listview);
2) Create adapter One more time with changed values
MyAdapter myAdapter = new MyAdapter(getApplicationContext(),
R.layout.locations_list_item_layout,dataArray;
mListView.setAdapter(myAdapter);
setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
public void onItemSelected(AdapterView<?> adapterView,
View view, int i, long l) {
myAdapter = new MyAdapter(getApplicationContext(),
//pass changed values vlues array R.layout.locations_list_item_layout,dataArray;
mListView.setAdapter(myAdapter);
}
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
Declare fulllist as Globle Variable and used static arraylist .
public class Lucenconcept extends Activity {
Button btn1;
EditText mEdit;
String txt2;
public ListAdapter adapter;
private ListView lv;
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
File index = new File("/sdcard/index/");
index.mkdir();
mEdit = (EditText)findViewById(R.id.editText1);
lv=(ListView) findViewById(android.R.id.list);
btn1 = (Button)findViewById(R.id.button1);
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Analyzer analyzer = new StandardAnalyzer();
IndexSearcher indexSearcher;
try {
indexSearcher = new IndexSearcher("/sdcard/index/");
QueryParser parser = new QueryParser("text", analyzer);
Hits hits = indexSearcher.search( parser.parse("("+ "text:" +mEdit.getText().toString() + ")"));
String txt2[] =new String[100];
String txt="";
for (int i = 0; i < hits.length(); i++) {
Document hitDoc = hits.doc(i);
Log.i("TestAndroidLuceneActivity", "Lucene: " +hitDoc.get("title")+ hitDoc.get("path"));
txt=hitDoc.get("title");
txt2[i]=txt;
String location=hitDoc.get("path");
}
lv.setAdapter(new ArrayAdapter
<String>
(Lucenconcept.this,android.R.layout.simple_list_item_1 ,txt2));
indexSearcher.close();
}
});
}
}
I m able show title on list view I want to display path hitDoc.get("path") from this string on item selct in next activity ..
Cud any one plz help meam not able to display url in next activty while I have put all the think manifest and all the I think there is mistake in postion plz help me..
Use Intent for passing data between activities
Refer Intent example