Populate ListView with ArrayList item on button click

Populate ListView with ArrayList item on button click - android

I have an arraylist List<Cars> myCars = new ArrayList<Cars>(); My MainActivity layout has a listview and a button. There is one more layout
("each_car.xml") and its content is as below:-
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="#+id/tv_carName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView" />
<TextView
android:id="#+id/tv_carMaker"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView" />
</LinearLayout>
</LinearLayout>
My Cars class has two fields,"name" and "manufacturer".
public class Cars{
String name;
String manufacturer;
}
I am populating this list(myCars) through an async-task. After the task is complete i.e. inside onPostExecute(), I am calling a method in my MainActivity
which will populate a listview with the items in the list. Below is the method :-
public void populateListView(List<Cars> data){
ArrayAdapter<Cars> carAdapter = new CarAdapter(MainActivity.this, data);
ListView dataList = (ListView) findViewById(R.id.car_listView);
dataList.setAdapter(carAdapter);
}
Below is my CarAdapter class :-
public class CarAdapter extends ArrayAdapter<Cars>{
private LayoutInflater inflater;
List<Cars> dummyData = new ArrayList<Cars>();
MainActivity host;
public CarAdapter(MainActivity host, List<Cars> data)
{
super(host,R.layout.each_car,data);
inflater = host.getWindow().getLayoutInflater();
dummyData = data;
}
#Override
public View getView(int position, View convertView, ViewGroup parent)
{
View itemView = convertView;
if(itemView == null)
{
itemView = inflater.inflate(R.layout.each_car,parent,false);
}
Cars currentData = dummyData.get(position);
Log.d("Testing Position","Position :- "+position);
TextView carName = (TextView) itemView.findViewById(R.id.tv_carName);
carName.setText(currentData.getName());
TextView carMaker = (TextView) itemView.findViewById(R.id.tv_carMaker);
carMaker.setText(currentData.getManufacturer());
return itemView;
}
}
This is filling out the listview with the entire List (myCars) at once.
Problem :- I want to populate the listView with one item at a time when I click the button.I am not sure how should I modify my code.

Check this link for custom adapterenter link description here. Once the list is populated pass the list into constructor of adapter and don't forget to call notifydatasetchanged. It will update the listview whenever an new item is added or removed from a listview.

This may help you ...
public class car extends AsyncTask<Void, Void, ArrayList<Cars> {
#Override
protected ArrayList<Cars> doInBackground(Void... params) {
... add your list here...
return myCars ;
}
#Override
protected void onPostExecute(ArrayList<Cars> result) {
super.onPostExecute(result);
//as per your requirement
adapter_car = new SimpleAdapter(ExchangeRateActivity.this, result,
R.layout.row, from, to);
list_view.setAdapter(adapter_car);
}

Here is a sample and easy way first you want to give the elements of 0 index element then on the next click you first clear the listview and then call your Adapter class with 2 element and repeat the same thing with some counter that takes the number of click and call you Adapter class with the limit of that Array list May be this Strategy help you..

Here are a couple of tutorials. You need to do some research and follow tutorials if you do not know what to do. link one, link two and link three
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content"></ListView>
</RelativeLayout>
adapter class
public class myListAdapter extends BaseAdapter{
List<String> item_list = new ArrayList<String>();
public myListAdapter(){
}
void add(String item_text){
item_list.add(item_text);
}
#Override
public int getCount() {
// TODO Auto-generated method stub
return item_list.size();
}
#Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
#Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return 0;
}
#Override
public View getView(int position, View arg1, ViewGroup arg2) {
// TODO Auto-generated method stub
LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.list_item, null);
TextView tvText = (TextView)view.findViewById(R.id.list_text);
tvText.setText(item_list.get(position));
return null;
}
}
list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView
android:id="#+id/list_text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
Implementation in onCreate:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myListAdapter adapter = new myListAdapter();
ListView list = (ListView) findViewById(R.id.list);
adapter.add("Some value");
list.setAdapter(adapter);
}

Related

How to create Listview items + Button in each row?

I am new to android programming and this task is really need for my school project. Please kindly help me.
I've string array List - (retrieved from csv)
list = new ArrayList<>(Arrays.asList("111,222,333,444,555,666".split(",")));
myList.setAdapter(new ArrayAdapter<String>(getActivity(),R.layout.cell,list));
The result is showing only line by line text of arrayList. I want to add button to each generated line by line to delete clicked row.
Please how can I do this. Thank you for understanding my problem.

You have to create a custom layout xml which having a single item then you will add your button to this layout along with any other items.
CustomLayout.Xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/tvContact"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="18sp"
android:textStyle="bold" />
<Button
android:id="#+id/btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Call" />
</RelativeLayout>
Now after creating custom item layout you need listview which holds all items.
MainActivity.xml
.
.
<ListView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent" />
.
.
Now in java file just set adapter with our custom layout xml
.
.
list = new ArrayList<String>(Arrays.asList("111,222,333,444,555,666".split(",")));
listview.setAdapter(new MyCustomAdapter(list, context) );
.
.
Custom adapter Class
public class MyCustomAdapter extends BaseAdapter implements ListAdapter {
private ArrayList<String> list = new ArrayList<String>();
private Context context;
public MyCustomAdapter(ArrayList<String> list, Context context) {
this.list = list;
this.context = context;
}
#Override
public int getCount() {
return list.size();
}
#Override
public Object getItem(int pos) {
return list.get(pos);
}
#Override
public long getItemId(int pos) {
return list.get(pos).getId();
//just return 0 if your list items do not have an Id variable.
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = convertView;
if (view == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.CustomLayout, null);
}
//Handle TextView and display string from your list
TextView tvContact= (TextView)view.findViewById(R.id.tvContact);
tvContact.setText(list.get(position));
//Handle buttons and add onClickListeners
Button callbtn= (Button)view.findViewById(R.id.btn);
callbtn.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
//do something
}
});
addBtn.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
//do something
notifyDataSetChanged();
.
}
});
return view;
}
}

We have need ListviewActivity for listing your data
SchoolAdapter which is custom adapter to inflate each individual row
activity_listview which is layout for ListviewActivity
view_listview_row which is required for each individual row
Now create all file as below
For ListviewActivity,
public class ListviewActivity extends AppCompatActivity {
private ListView mListview;
private ArrayList<String> mArrData;
private SchoolAdapter mAdapter;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_listview);
mListview = (ListView) findViewById(R.id.listSchool);
// Set some data to array list
mArrData = new ArrayList<String>(Arrays.asList("111,222,333,444,555,666".split(",")));
// Initialize adapter and set adapter to list view
mAdapter = new SchoolAdapter(ListviewActivity.this, mArrData);
mListview.setAdapter(mAdapter);
mAdapter.notifyDataSetChanged();
}
For SchoolAdapter,
public class SchoolAdapter extends BaseAdapter {
private Context mContext;
private ArrayList<String> mArrSchoolData;
public SchoolAdapter(Context context, ArrayList arrSchoolData) {
super();
mContext = context;
mArrSchoolData = arrSchoolData;
}
public int getCount() {
// return the number of records
return mArrSchoolData.size();
}
// getView method is called for each item of ListView
public View getView(int position, View view, ViewGroup parent) {
// inflate the layout for each item of listView
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.view_listview_row, parent, false);
// get the reference of textView and button
TextView txtSchoolTitle = (TextView) view.findViewById(R.id.txtSchoolTitle);
Button btnAction = (Button) view.findViewById(R.id.btnAction);
// Set the title and button name
txtSchoolTitle.setText(mArrSchoolData.get(position));
btnAction.setText("Action " + position);
// Click listener of button
btnAction.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// Logic goes here
}
});
return view;
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}}
For activity_listview,
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#D1FFFF"
android:orientation="vertical">
<ListView
android:id="#+id/listSchool"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:divider="#0000CC"
android:dividerHeight="0.1dp"></ListView>
For view_listview_row,
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingBottom="7.5dp"
android:paddingLeft="15dp"
android:paddingRight="15dp"
android:paddingTop="7.5dp">
<TextView
android:id="#+id/txtSchoolTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="2dp"
android:text="TextView"
android:textColor="#android:color/black"
android:textSize="20dp" />
<Button
android:id="#+id/btnAction"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Click Me" />
At last but not least, do not forgot to add your activity in manifest.xml

Create a custom list view in another file with the only content of each item in the list.
Then create a Custom Adapter extending BaseAdapter and bind it.
Please refer to this website for example.
https://looksok.wordpress.com/tag/listview-item-with-button/
OR
http://www.androidhive.info/2012/02/android-custom-listview-with-image-and-text/

How to create two different LinearLayout in a same ListView?

i want to combine two LinearLayout, both have different TextView arrangement in them, in a single ListView. so the final look should be like below:
and i run it with my code, but the app wouldn't start. below are my code.
Activity class:
public class MainActivity extends Activity {
// Create list of items
String[] publicModeItems = {
"AAAAA",
"BBBBB"
};
String[] publicModeParameters = {
"YES",
"NO"
};
String[] publicModeResetExe = {
"CCCCC",
"DDDDD"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
populateListView();
}
private void populateListView() {
CustomList adapter1 = new CustomList(this, publicModeItems, publicModeParameters);
// Build adapter
ArrayAdapter<String> adapter2 = new ArrayAdapter<String>(
this, // context for the activity
R.layout.text_view_test, // layout to use (create)
publicModeResetExe); // items to display
// Configure the list view
ListView list = (ListView) findViewById(R.id.PublicModeListView);
list.setAdapter(adapter1);
list.setAdapter(adapter2);
}
private class CustomList extends ArrayAdapter<String> {
private final Activity context;
private final String[] publicModeItems;
private final String[] publicModeParameters;
public CustomList(Activity context,
String[] publicModeItems,
String[] publicModeParameters) {
super(context, R.layout.text_views_1, publicModeItems);
this.context = context;
this.publicModeItems = publicModeItems;
this.publicModeParameters = publicModeParameters;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
LayoutInflater layoutinflater = context.getLayoutInflater();
View rowView = layoutinflater.inflate(R.layout.text_views_1, null, true);
TextView txtPublicModeItems = (TextView) rowView.findViewById(R.id.PublicModeItems);
TextView txtPublicModeParameters = (TextView) rowView.findViewById(R.id.PublicModeParameters);
txtPublicModeItems.setText(publicModeItems[position]);
txtPublicModeParameters.setText(publicModeParameters[position]);
return rowView;
}
}
}
text_views_1 xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/PublicModeLayoutForTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="#+id/PublicModeItems"
android:layout_width="200sp"
android:layout_height="wrap_content"
android:textColor="#drawable/text_color_change" />
<TextView
android:id="#+id/PublicModeOpenBracket"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="["
android:textColor="#drawable/text_color_change" />
<TextView
android:id="#+id/PublicModeParameters"
android:layout_width="100sp"
android:layout_height="wrap_content"
android:gravity="end"
android:textColor="#drawable/text_color_change" />
<TextView
android:id="#+id/PublicModeCloseBracket"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="]"
android:textColor="#drawable/text_color_change" />
</LinearLayout>
text_view_test xml:
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textColor="#drawable/text_color_change" >
</TextView>
activity_main xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/PublicModeListViewLayout01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#color/black"
android:baselineAligned="true"
android:orientation="vertical"
tools:context="com.example.mycalendar.MainActivity" >
<LinearLayout
android:id="#+id/PublicModeListViewLayout02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:background="#drawable/custom_border"
android:padding="5dp" >
<ListView
android:id="#+id/PublicModeListView"
android:layout_width="308dp"
android:layout_height="wrap_content"
android:choiceMode="singleChoice"
android:listSelector="#color/yellow"
android:smoothScrollbar="true" >
</ListView>
</LinearLayout>
</LinearLayout>
Problem : I just run my code just now, and only 'CCCCC' and 'DDDDD' is showing. so do you have any idea on this?

You should inherit your list adapter from BaseAdapter rather than ArrayAdapter.
Rewrite adapter's getView() method to inflate layout according position, like below.
public View getView(int position, View convertView, ViewGroup parent) {
...
View rootView = null;
if (position == 0 || position == 1) {
rootView = layoutinflater.inflate(R.layout.text_views_1, null, true);
} else {
rootView = layoutinflater.inflate(R.layout.text_views, null, true);
}
...
return rootView;
}

You set the list adapter twice
list.setAdapter(adapter1);
list.setAdapter(adapter2);
in this case the current adapter is the second, not them both.
Use ListView with SimpleAdapter or a custom adapter and that will solve all your problems, check out this for SimpleAdapter tutorial to learn a the basics and this tutorial to learn how you can make multiple views instead of just 1. This tutorial is about creating custom adapter
BTW, I have few comments on your code and xml layout
First, there is no need for 2 TextViews for your bracket, you can easily add them programmatically to the String[] or even to YES/NO TextView.
Second, You're not using a ViewHolder in your CustomList adapter and this is not a good practice as every time you scroll your list, it creates new view although it can use already existing one.

I already solve this problem. but it seems not so convenient to use this method.
public class PublicModeActivity extends Activity {
// Create list of items
String[] publicModeItems = {
"AAAAA",
"BBBBB"
};
String[] publicModeParameters = {
"YES",
"NO"
String[] publicModeResEx = {
"",
"",
"CCCCC",
"DDDDD"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
populateListView();
}
private void populateListView() {
CustomList adapter = new CustomList(this, publicModeItems, publicModeParameters, publicModeResEx);
// Configure the list view
ListView list = (ListView) findViewById(R.id.PublicModeListView);
list.setAdapter(adapter);
}
private class CustomList extends BaseAdapter {
private final Activity context;
private final String[] publicModeItems;
private final String[] publicModeParameters;
private final String[] publicModeResEx;
public CustomList(Activity context,
String[] publicModeItems,
String[] publicModeParameters,
String[] publicModeResEx) {
super();
this.context = context;
this.publicModeItems = publicModeItems;
this.publicModeParameters = publicModeParameters;
this.publicModeResEx = publicModeResEx;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
LayoutInflater layoutinflater = context.getLayoutInflater();
View rowView = null;
Log.i("PublicModeActivity", "" + position);
if (position < 2) {
rowView = layoutinflater.inflate(R.layout.text_views_1, null, true);
TextView txtPublicModeItems = (TextView) rowView.findViewById(R.id.PublicModeItems);
TextView txtPublicModeParameters = (TextView) rowView.findViewById(R.id.PublicModeParameters);
txtPublicModeItems.setText(publicModeItems[position]);
txtPublicModeParameters.setText(publicModeParameters[position]);
} else {
rowView = layoutinflater.inflate(R.layout.text_view_test, null, true);
TextView txtPublicModeResEx = (TextView) rowView.findViewById(R.id.PublicModeResEx);
txtPublicModeResEx.setText(publicModeResEx[position]);
}
return rowView;
}
#Override
public int getCount() {
return 4;
}
#Override
public Object getItem(int position) {
return position;
}
#Override
public long getItemId(int position) {
return position;
}
}
}
I need to put that blank string "", to match the number of row with the upper layout (text_views_1) even-though those blank string are use in different layout. so it is not so convenient especially when you want to display so many data. If someone here have much simpler method than this. feel free to share with me/us. i'm eager to learn. thank you!

String Array With Custom Adapters

Can we use String array with custom adapter and data should be display in Listview?
I mean something like that
String [] s= {"cars","bike","train"};
Now how this string array will attach with Custom adapter and how data will show in the ListView.
I know this is easy with ArrayList.
But I want to do it with simple String Array.

Well, you can use a custom adapter for that. But you could also use the ArrayAdapter class if you just want to show text on your ListView.
But, if for whatever reason you want to create a custom adapter, try the following...
In this particular case I'm subclassing the BaseAdapter class.
This custom adapter will take hold of my data model, and will inflate the data to my ListView rows.
First, I'll create the XML of my custom row. You can see the code below.
item.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Test text"
android:id="#+id/tv"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_centerVertical="true"/>
</RelativeLayout>
Here I've created a row that displays a text.
Now, I'll create my custom adapter to handle this XML. As you can see below.
MyAdapter.java
public class MyAdapter extends BaseAdapter {
private static final String LOG_TAG = MyAdapter.class.getSimpleName();
private Context context_;
private ArrayList<String> items;
public MyAdapter(Context context, ArrayList<String> items) {
this.context_ = context;
this.items = items;
}
#Override
public int getCount() {
return items.size();
}
#Override
public Object getItem(int position) {
return items.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater mInflater = (LayoutInflater)
context_.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
convertView = mInflater.inflate(R.layout.item_mail, null);
}
TextView tv = (TextView) convertView.findViewById(R.id.tv);
String text = items.get(position);
Log.d(LOG_TAG,"Text: " + text);
tv.setText(text);
return convertView;
}
}
Ok. Now we have everything to make this work. In your Activity class, do something like that:
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<TextView
android:text="#string/hello_world"
android:id="#+id/tv_header"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/tv_header">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add item"
android:id="#+id/button"
android:layout_gravity="center" />
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/listView" />
</LinearLayout>
</RelativeLayout>
MainActivity.java
public class MainActivity extends ActionBarActivity {
private int numItem = 1; // Dummy int to create my items with different numbers.
private MyAdapter myAdapter; // Your custom adapter.
private ArrayList<String> items; // This is going to be your data structure, every time you change it, call the notifyDataSetChanged() method.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button bt = (Button) findViewById(R.id.button);
ListView lv = (ListView) findViewById(R.id.listView);
items = new ArrayList<>();
myAdapter = new MyAdapter(this,items);
lv.setAdapter(myAdapter);
bt.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
addItem(); // The method I'm using to insert the item. Look for it below.
}
});
}
private void addItem() {
items.add("Text " + numItem++);
mailAdapter.notifyDataSetChanged(); // Notifying the adapter that my ArrayList was modified.
}
}
This should do the trick.
From what you told me, you want to use a String array instead of a ArrayList<String>. Well, change the adapter to the following.
MyAdapter.java
public class MyAdapter extends BaseAdapter {
private static final String LOG_TAG = MyAdapter.class.getSimpleName();
private Context context_;
private String[] items;
public MyAdapter(Context context, String[] items) {
this.context_ = context;
this.items = items;
}
#Override
public int getCount() {
return items.length;
}
#Override
public Object getItem(int position) {
return items[position];
}
#Override
public long getItemId(int position) {
return position;
}
// Rest of the code... Same as before.
}
MainActivity.java
public class MainActivity extends ActionBarActivity {
private MyAdapter myAdapter; // Your custom adapter.
private String[] items;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button bt = (Button) findViewById(R.id.button);
ListView lv = (ListView) findViewById(R.id.listView);
items = {"Whatever","String","You","Like"};
myAdapter = new MyAdapter(this,items);
lv.setAdapter(myAdapter);
}
}
The problem with this approach: Your adapter will have a fixed size, which will be the size of your String array once you create it. And you won't be able to make it bigger, unless you create another adapter with a different String array.
This question discusses this matter.

Change color of Text inside List view in android

I have to change color of multiple selected items (Text views) in List view. What I am doing here is, when user selects items from list views, color should be change to BLUE and when user deselects items, color should change to by default color (here Black). I have been through few tutorials and implemented one little demo. But I am not getting, how to deal with color change. Below is my code...
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:layout_height="wrap_content"
android:id="#+id/listView2"
android:layout_width="match_parent">
</ListView>
</LinearLayout>
listitem.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="TextView"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
MainActivity.java
public class MainActivity extends Activity
{
/** Called when the activity is first created. */
public View row;
ListView lview;
ListViewAdapter lviewAdapter;
private final static String month[] = {"January","February","March","April","May",
"June","July","August","September","October","November","December"};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lview = (ListView) findViewById(R.id.listView2);
lviewAdapter = new ListViewAdapter(this, month);
lview.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
lview.setAdapter(lviewAdapter);
lview.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// TODO Auto-generated method stub
}
});
}
}
ListViewAdapter.java
public class ListViewAdapter extends BaseAdapter
{
ArrayList<Boolean> saved = new ArrayList<Boolean>();
Activity context;
String title[];
String description[];
public ListViewAdapter(Activity context, String[] title) {
super();
this.context = context;
this.title = title;
}
public int getCount() {
// TODO Auto-generated method stub
return title.length;
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
private class ViewHolder {
TextView txtViewTitle;
}
public View getView(int position, View convertView, ViewGroup parent)
{
// TODO Auto-generated method stub
ViewHolder holder;
LayoutInflater inflater = context.getLayoutInflater();
if (convertView == null)
{
convertView = inflater.inflate(R.layout.listitem_row, null);
holder = new ViewHolder();
holder.txtViewTitle = (TextView) convertView.findViewById(R.id.textView1);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
holder.txtViewTitle.setText(title[position]);
return convertView;
}
}

lview.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
TextView textView1 = (TextView) arg1.findViewById(R.id.textView1);
if(lv.isItemChecked(arg2))
textView1.setTextColor(your selected state color);
else
textView1.setTextColor(your unselected state color);
}
});

Just create the selector.xml inside res/drawable like i have created the one below.:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
<item android:state_pressed="true" android:color="#fff"/>
<item android:state_enabled="false" android:color="#cc003300"/>
<item android:color="#cc003300"></item>
</selector>
then assign it to the textview in xml.
android:textColor="#drawable/selector_btn_textcolor_green"
update your code as
<TextView
android:id="#+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="TextView"
android:textColor="#drawable/selector_btn_textcolor_green"
android:textAppearance="?android:attr/textAppearanceLarge" />

for the listitem, you can keep the drawable as an xml resource which you can keep in drawable folder. In that you can handle pressed, focused, normal condition explicitly to different colors.

First of all you should get the selected position of your Item , so you can do this by passing the selected Item to your adapter in your List onItemClickListener :
in your adapter class add :
public void setSelectedPosition(int pos)
{
selectedPos = pos;
}
in your Activity you call this function of your adapter :
public void selectPosition(int position) {
((YourCustomAdapter)getListView().getAdapter()).setSelectedPosition(position);
}
and in your ListItemClick Listener of your List :
YourList.setOnItemClickListener(new OnItemClickListener()
{
#Override public void onItemClick(AdapterView<?> arg0, View arg1,int position, long arg3)
{
selectPosition(position);
}
});
here selectedPos is a global variable which take your Selected Item , so you have the selected Item in your Adapter, then you can use this in getView() function :
if(selectedPos == position)
{
rowView.setBackgroundResource(R.color.listselect_red);
}
else
{
rowView.setBackgroundResource(R.color.listselect_light_grey);
}

Create new layout xml file and copy the entire code from simple_list_item_1.xml in external libraries, then change according to you.
custom_text.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/text1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="#1ca099"
android:textSize="20dp"
android:padding="5dp"
android:gravity="center_vertical"
/>
Then in the activity.java file:
ListView lst=(ListView) findViewById(R.id.listView);
ArrayAdapter<String> adapter=new ArrayAdapter<String>(getApplicationContext(),R.layout.custom_text,cultural);
lst.setAdapter(adapter);

Android: ListView not refreshing on notifyDataSetChanged();

I've got a custom BaseAdapter and an add button in the main activity. The button opens a dialog with a textbox and you can add new elements to the list that way. The problem is that the list is not refreshing. In the onActivityResult() function I print the number of elements in the list and each time I hit OK in the dialog box the number increases, so I know it's just the refreshing that doesn't work. My BaseAdapter and my activity:
class ListaOrase extends BaseAdapter{
private Activity context;
ArrayList<String> orase;
public ListaOrase(Activity context){
this.context=context;
orase=new ArrayList<String>();
}
public void add(String string){
orase.add(string);
this.notifyDataSetChanged();
}
public View getView (int position, View convertView, ViewGroup list) {
View element;
if (convertView == null)
{
LayoutInflater inflater = context.getLayoutInflater();
element = inflater.inflate(R.layout.lista, null);
}
else element = convertView;
TextView elementLista=(TextView)element.findViewById(R.id.elementLista);
elementLista.setText(orase.get(position));
return element;
}
}
public class WeatherAppActivity extends ListActivity {
Button buton;
ListaOrase lista;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
lista=new ListaOrase(this);
buton=(Button)findViewById(R.id.buton);
lista.add("Bucuresti");
lista.add("Sibiu");
setListAdapter(lista);
}
public void add(View view){
Intent intent=new Intent();
intent.setClass(this, Adauga.class);
startActivityForResult(intent, 0);
}
public void onActivityResult (int requestCode, int responseCode, Intent data){
System.out.println("Apelata");
if(responseCode==1){
lista.add(data.getStringExtra("oras")); // e chiar getText()
System.out.println(lista.getCount());
lista.notifyDataSetChanged();
}
}
}
As you can see, I'm trying to refresh (notifyDataSetChanged();) both when adding a new element (in the BaseAdapter extending class) and in method onActivityResult, after the dialog passes the new element to the main Activity. I repeat, the element IS added to the list because the count increases, it just doesn't refresh.
Thanks for your answers!

It's normal that it doesn't refresh, you are adding an item to "lista" but the adapter keeps its own copy of that list, so or you set again the list in the adapter and then you call notifyDataChanged or you add the new item to the adapter.
Anyway I see couple of weird things, I thing you could semplify everything using an array adapter, you don't need to implement add,etc. I wrote some code simplyfing yours:
public class WeatherAppActivity extends ListActivity {
Button buton;
ItemsAdapter lista;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
List<String> initialList = new ArrayList<String>();
initialList.add("Bucuresti");
initialList.add("Sibiu");
lista=new ItemsAdapter(this, initialList);
buton=(Button)findViewById(R.id.button1);
buton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
lista.add(""+System.currentTimeMillis()); // e chiar getText()
lista.notifyDataSetChanged();
}
});
setListAdapter(lista);
}
class ItemsAdapter extends ArrayAdapter<String> {
public ItemsAdapter(Context context, List<String> list) {
super(context, R.layout.lista, list);
}
#Override
public View getView(final int position, View row, final ViewGroup parent) {
final String item = getItem(position);
ItemWrapper wrapper = null;
if (row == null) {
row = getLayoutInflater().inflate(R.layout.lista, parent, false);
wrapper = new ItemWrapper(row);
row.setTag(wrapper);
} else {
wrapper = (ItemWrapper) row.getTag();
}
wrapper.refreshData(item);
return row;
}
class ItemWrapper {
TextView text;
public ItemWrapper(View row) {
text = (TextView) row.findViewById(R.id.elementLista);
}
public void refreshData(String item) {
text.setText(item);
}
}
}
}
These are the xml that I have used:
main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="63dp"
android:text="Button" />
<ListView
android:id="#id/android:list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" >
</ListView>
</RelativeLayout>
lista.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/elementLista"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Medium Text"
android:textAppearance="?android:attr/textAppearanceMedium" />
</LinearLayout>
This is the version of the adapter using a baseadapter:
class ItemsBaseAdapter extends BaseAdapter {
private List<String> items;
private Context mContext;
public ItemsBaseAdapter(Context context, List<String> list) {
items = list;
mContext = context;
}
public void addItem(String str) {
items.add(str);
}
#Override
public View getView(final int position, View row, final ViewGroup parent) {
final String item = (String) getItem(position);
ItemWrapper wrapper = null;
if (row == null) {
row = getLayoutInflater().inflate(R.layout.lista, parent, false);
wrapper = new ItemWrapper(row);
row.setTag(wrapper);
} else {
wrapper = (ItemWrapper) row.getTag();
}
wrapper.refreshData(item);
return row;
}
class ItemWrapper {
TextView text;
public ItemWrapper(View row) {
text = (TextView) row.findViewById(R.id.elementLista);
}
public void refreshData(String item) {
text.setText(item);
}
}
#Override
public int getCount() {
return items.size();
}
#Override
public Object getItem(int position) {
return items.get(position);
}
#Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
}
And this is the version of the list item wich also include an imageview on the left:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<ImageView
android:layout_height="wrap_content"
android:src="#android:drawable/btn_star_big_on"
android:scaleType="fitCenter"
android:layout_width="wrap_content"
/>
<TextView
android:id="#+id/elementLista"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Medium Text"
android:textAppearance="?android:attr/textAppearanceMedium"
/>
</LinearLayout>

Develop Reference

The Android operating system is a mobile operating system that was developed by Google (GOOGL?) to be primarily used for touchscreen devices, cell phones, and tablets.

Populate ListView with ArrayList item on button click - android

Check this link for custom adapterenter link description here. Once the list is populated pass the list into constructor of adapter and don't forget to call notifydatasetchanged. It will update the listview whenever an new item is added or removed from a listview.

Related

How to create Listview items + Button in each row?

How to create two different LinearLayout in a same ListView?

String Array With Custom Adapters

Change color of Text inside List view in android

Android: ListView not refreshing on notifyDataSetChanged();

Categories

Resources