ImageView setVisibility(0) and null pointer exception - android

I have 2 xml files, a main file where I have a listView and the other where I am making some customisations to my listView.
The second xml is used on my Custom ArrayAdapter.
In the second xml i have a ImageView which I would like to set to visible at one moment but I am getting the null pointer exception because i am never setting with setCurrentView the second xml file where is my ImageView.
I am trying to do this:
ImageView statusOk=(ImageView)findViewById(R.id.statusOkImage);
statusOk.setVisibility(0);
Could you please tell me how to resolve that?
Thank you.
Edit:
Here is more code:
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:id="#+id/ListView01"
android:layout_height="wrap_content"
android:layout_width="fill_parent"/>
</LinearLayout>
Second 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">
<ImageView
android:id="#+id/statusOkImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/status_ok"
android:visibility="invisible"/>
<TextView android:id="#+id/name"
android:textSize="14sp"
android:textStyle="bold"
android:textColor="#FFFF00"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView android:id="#+id/cityState"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView android:id="#+id/phone"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
MainActivity:
public class TestListActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ArrayList<SearchResults> searchResults = GetSearchResults();
final ListView lv1 = (ListView) findViewById(R.id.ListView01);
lv1.setAdapter(new MyCustomBaseAdapter(this, searchResults));
}
private ArrayList<SearchResults> GetSearchResults(){
ArrayList<SearchResults> results = new ArrayList<SearchResults>();
SearchResults sr1 = new SearchResults();
sr1 = new SearchResults();
sr1.setName("Fred Jones");
sr1.setCityState("Las Vegas, NV");
sr1.setPhone("612-555-8214");
results.add(sr1);
return results;
}
}
custom Adapter:
public class MyCustomBaseAdapter extends BaseAdapter {
private static ArrayList<SearchResults> searchArrayList;
private LayoutInflater mInflater;
public MyCustomBaseAdapter(Context context, ArrayList<SearchResults> results) {
searchArrayList = results;
mInflater = LayoutInflater.from(context);
}
public int getCount() {
return searchArrayList.size();
}
public Object getItem(int position) {
return searchArrayList.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.custom_row_view, null);
holder = new ViewHolder();
holder.txtName = (TextView) convertView.findViewById(R.id.name);
holder.txtCityState = (TextView) convertView.findViewById(R.id.cityState);
holder.txtPhone = (TextView) convertView.findViewById(R.id.phone);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
mInflater=(LayoutInflater)getSystemService(LAYOUT_INFLATER_SERVICE);
View view=mInflater.inflate(R.layout.custom_row_view, null);
ImageView statusOk=(ImageView)view.findViewById(R.id.imageView1);
statusOk.setVisibility(View.VISIBLE);
holder.txtName.setText(searchArrayList.get(position).getName());
holder.txtCityState.setText(searchArrayList.get(position).getCityState());
holder.txtPhone.setText(searchArrayList.get(position).getPhone());
return convertView;
}
static class ViewHolder {
TextView txtName;
TextView txtCityState;
TextView txtPhone;
}
}
And finnaly the resource class for the listView
public class SearchResults {
private String name = "";
private String cityState = "";
private String phone = "";
public void setName(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setCityState(String cityState) {
this.cityState = cityState;
}
public String getCityState() {
return cityState;
}
public void setPhone(String phone) {
this.phone = phone;
}
public String getPhone() {
return phone;
}
}

To set visibility view defined in xml, you need to inflate that view in activity, setContentView do it automatically, and as you are not invoking setContentView on second xml, then use:
LayoutInflater inflater=(LayoutInflater)getSystemService(Layout_INFLATER_SERVICE);
View view=inflater.inflate(R.layout.secondxml, null);
and then find your view from that view:
ImageView statusOk=(ImageView)view.findViewById(R.id.statusOkImage);
statusOk.setVisibility(0);
but it will work only for view object, it does not affect original xml.

Change to :
statusOk.setVisibility(View.INVISIBLE);
and check is image is ready to use findViewById, like you call the method and after do setContentView or if it really is ImageView, etc.

Here is the solution for accessing the view from another class.
Note : currentActivity is the context of root class
LayoutInflater inflater = (LayoutInflater)currentActivity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view=inflater.inflate(R.layout.secondxml, null);

Use LayoutInflater.getLayoutInflater() to instantiate layout XML file into its corresponding View objects.

ImageView imgview=(ImageView)findViewById(R.id.imageView1);
imgview.setVisibility(View.INVISIBLE); //for invisibility.
imgview.setVisibility(View.VISIBLE); //make your image visible where ever you want

Related

how to hide/show Imageview on Button Click for Custom Adapter Layout

I have custom adapter for ListView. The ListView is in activity_main.xml and I have a ImageView in CustomAdapter layout which is populated with ListView using CustomAdapter.
My Question is I have to hide/show that image which is in custom layout with a button present in main layout. Like if there is 10 row in my ListView and 10 row have that image. I want to hide only for the particular row.
I hope you understand my question...Thanks in Advance
Here's my ListViewAdapter
public class ListViewAdapter extends ArrayAdapter<FileName> {
Context context;
LayoutInflater inflater;
List<FileName> filenames;
private SparseBooleanArray mSelectedItemsIds;
public ListViewAdapter(Context context,int resource,List<FileName> filenames) {
super(context, resource, filenames);
mSelectedItemsIds = new SparseBooleanArray();
this.context = context;
this.filenames = filenames;
inflater = LayoutInflater.from(context);
}
private class ViewHolder {
TextView filename;
TextView shorttext;
ImageView imageView;
}
public View getView(int position, View view, ViewGroup parent) {
final ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = inflater.inflate(R.layout.listview_item, null);
// Locate the TextViews in listview_item.xml
holder.filename = (TextView) view.findViewById(R.id.item_title);
holder.shorttext = (TextView) view.findViewById(R.id.item_desc);
holder.imageView = (ImageView) view.findViewById(R.id.lock);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
// Capture position and set to the TextViews<br />
holder.filename.setText(filenames.get(position).getName());
holder.shorttext.setText(filenames.get(position).getShorttext());
return view;
}
}
name = filenames.get(position).getName(); //getting the positin from listview
filenames.set(name,FileName.isVisible = true); //getting error on isVisible
I have writen a Sample code and tested
MainActivity
public class MainActivity extends AppCompatActivity {
List<FileName> filenames;
DBhelper dBhelper;dBhelper
SQLiteDatabase sqLiteDatabase;
ListViewAdapter listViewAdapter;
ListView listView;
ImageView lock;
String name;
//temporary button i have added
Button lockBTN;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sample);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
listView = (ListView) findViewById(R.id.lv_filename);
lockBTN = (Button) findViewById(R.id.lock);
filenames = getResult();
listViewAdapter = new ListViewAdapter(this, filenames);
listView.setAdapter(listViewAdapter);
lockBTN.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//giving statically position is 2
int position = 2;
// when you press menu button or any other button
FileName fileName = filenames.get(position);
//here you can set true-Show and false-hide imageview
fileName.setVisible(true);
//and update the list
filenames.set(position, fileName);
listViewAdapter.notifyDataSetChanged();
}
});
}
//temporary data to show on listview
private List<FileName> getResult() {
List<FileName> fileNames = new ArrayList<>();
String[] nameArr = {"Name1", "Name2", "Name3"};
String[] shortTextArr = {"ShortText1", "ShortText2", "ShortText3"};
for(int i=0; i<nameArr.length;i ++){
FileName fileName = new FileName();
fileName.setName(nameArr[i]);
fileName.setShorttext(shortTextArr[i]);
//setting default is hide to imageview
fileName.setVisible(false);
fileNames.add(fileName);
}
return fileNames;
}
}
FileName
public class FileName {
private String name;
private String shorttext;
private boolean visible = true;
public String getName() {
return name;
}
public void setName(String _name) {
this.name = _name;
}
public String getShorttext() {
return shorttext;
}
public void setShorttext(String _shorttext) {
this.shorttext = _shorttext;
}
public boolean isVisible() {
return visible;
}
public void setVisible(boolean visible) {
this.visible = visible;
}
}
ListViewAdapter
public class ListViewAdapter extends BaseAdapter{
Context context;
LayoutInflater inflater;
List<FileName> filenames;
private SparseBooleanArray mSelectedItemsIds;
public ListViewAdapter(Context context, List<FileName> filenames) {
mSelectedItemsIds = new SparseBooleanArray();
this.context = context;
this.filenames = filenames;
inflater = LayoutInflater.from(context);
}
#Override
public int getCount() {
return filenames.size();
}
#Override
public Object getItem(int position) {
return filenames.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
public View getView(int position, View view, ViewGroup parent) {
final ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = inflater.inflate(R.layout.listview_item, null);
// Locate the TextViews in listview_item.xml
holder.filename = (TextView) view.findViewById(R.id.item_title);
holder.shorttext = (TextView) view.findViewById(R.id.item_desc);
holder.imageView = (ImageView) view.findViewById(R.id.lock);
//holder.filename.setPaintFlags(holder.filename.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
// Capture position and set to the TextViews<br />
holder.filename.setText(filenames.get(position).getName());
holder.shorttext.setText(filenames.get(position).getShorttext());
// check weather image is to show/hide
if (filenames.get(position).isVisible()) {
holder.imageView.setVisibility(View.VISIBLE);
} else {
holder.imageView.setVisibility(View.GONE);
}
return view;
}
private class ViewHolder {
TextView filename;
TextView shorttext;
ImageView imageView;
}
}
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="5dp"
android:orientation="vertical">
<ListView
android:id="#+id/lv_filename"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/lock"/>
<Button
android:id="#+id/lock"
android:layout_alignParentBottom="true"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Lock"/>
</RelativeLayout>
custom_list_item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="1">
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/utilities_notepad_icon" />
<LinearLayout
android:layout_width="232dp"
android:layout_height="match_parent"
android:orientation="vertical"
android:layout_weight="0.77">
<TextView
android:id="#+id/item_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingBottom="1dp"
android:paddingTop="5dp"
android:text="Item Title"
android:textSize="16dp" />
<TextView
android:id="#+id/item_desc"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:maxLength="35"
android:paddingBottom="5dp"
android:paddingTop="1dp"
android:text="Item Description"
android:textColor="#999"
android:textSize="10dp" />
</LinearLayout>
<ImageView
android:id="#+id/lock"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/lo"
android:layout_marginTop="13sp" />
</LinearLayout>
Take a extra variable in your FileName class.
public class FileName {
public String name;
public String shortText;
public boolean visible = true; // Set the default value to true.
}
Now on external button click in your main layout, you might consider updating the list item accordingly. Just set the visible variable to false of that item you want to hide. Then call notifyDataSetChanged() on your adapter to reload the data.
And yes, in your adapter, just check the value of visible attribute and then decide to hide/show the ImageView. So the getView function of your adapter should look like this.
public View getView(int position, View view, ViewGroup parent) {
final ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = inflater.inflate(R.layout.listview_item, null);
// Locate the TextViews in listview_item.xml
holder.filename = (TextView) view.findViewById(R.id.item_title);
holder.shorttext = (TextView) view.findViewById(R.id.item_desc);
holder.imageView = (ImageView) view.findViewById(R.id.lock);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
// Capture position and set to the TextViews<br />
holder.filename.setText(filenames.get(position).getName());
holder.shorttext.setText(filenames.get(position).getShorttext());
// Hide/Show the ImageView
if (filenames.get(position).visible) holder.imageView.setVisibility(View.VISIBLE);
else holder.imageView.setVisibility(View.GONE);
return view;
}
I would suggest you to use RecyclerView instead of ListView. RecyclerView got more performance than the ListView. Now a days all are using RecyclerView instead of old ListView, it is quite easy to use as well.
And for handling your case create a function to remove the file name you wanted to remove in the RecyclerViewAdapter class as below
removeImageView(position){
fileNames.remove(position);
this.notifyItemRemoved(position);
}
notifyItemRemoved call will refresh the position in the recycler view and you will also get a nice view removing animation out of the box.

application crashes when trying work with custom list adapter, cant find the error

I'm trying to create simple list of Objects which i created
the objects are ShopListItem, this is the code of the class:
public class ShopListItem {
private String name;
private double price;
public ShopListItem(String name , double price)
{
this.name = name;
this.price = price;
}
public double getPrice() {
return price;
}
public String getName() {
return name;
}
}
this is the ArrayAdatpter class:
public class shopItemAdapter extends ArrayAdapter<ShopListItem> {
public shopItemAdapter(Context context, ArrayList<ShopListItem> items){
super(context, 0, items);
}
public View getView(int position, View convertView, ViewGroup parent) {
ShopListItem item = getItem(position);
if (convertView == null) {
convertView = LayoutInflater.from(getContext()).inflate(R.layout.shop_item_row, parent, false);
}
TextView name = (TextView) convertView.findViewById(R.id.itemName);
TextView price = (TextView) convertView.findViewById(R.id.itemPrice);
name.setText(item.getName());
price.setText(String.valueOf(item.getPrice()));
return convertView;
}
}
and this is my activity which is supposed to display this list:
public class check extends Activity {
ListView items = (ListView)findViewById(R.id.items);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_q);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
ShopListItem item1 = new ShopListItem("milk" , 5.9);
ShopListItem item2 = new ShopListItem("bamba" , 4);
ArrayList<ShopListItem> list = new ArrayList<ShopListItem>();
list.add(item1);
list.add(item2);
shopItemAdapter adapter = new shopItemAdapter(this , list);
items.setAdapter(adapter);
}
}
I open the activity from another activity when user clicks a button, this is the on click method:
public void openList(View view){
Intent intent = new Intent(HomeActivity.this , check.class);
this.startActivity(intent);
}
shop_item_row.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FFF9F9F9"
android:paddingRight="10dp"
android:paddingTop="10dp"
android:paddingBottom="10dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Medium Text"
android:id="#+id/itemName"
android:layout_weight="0.61"
android:layout_margin="5dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="Small Text"
android:id="#+id/itemPrice"
android:layout_margin="5dp" />
</LinearLayout>
and content_check.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
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"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="atoa.roomates.QA"
tools:showIn="#layout/activity_q">
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/items"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
thank you!
You are accessing view ListView items = (ListView)findViewById(R.id.items); before onCreate(). So move that line in onCreate method after setContentView().
initialize your list in setContentView instead of top
like following
ListView items;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_new_demo);
items = (ListView) findViewById(R.id.items);
after change this work fine.
public class shopItemAdapter extends ArrayAdapter<ShopListItem> {
private Context mContext;
private List<ShopListItem> mListShop;
public shopItemAdapter(Context context, int resource, ArrayList<ShopListItem> items){
super(context, resource, items);
this.mContext= context;
this.mListShop = items;
}
#Override
public int getCount() {
return mListShop.size();
}
#Override
public ShopListItem getItem(int position) {
return mListShop.get(position);
}
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
if (view == null) {
LayoutInflater inflater = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.shop_item_row, null);
holder = new ViewHolder();
holder.mTextPrice = (TextView) view.findViewById(R.id.itemPrice);
holder.mTextName = (TextView) view.findViewById(R.id.itemName);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
ShopListItem item = getItem(position);
holder.mTextName.setText(item.getName());
holder.mTextPrice.setText(item.getPrice());
return view;
}
public class ViewHolder {
public TextView mTextPrice;
public TextView mTextName;
}
}
In your Activity
public class check extends Activity {
ListView items;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_q);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
items = (ListView)findViewById(R.id.items);
ShopListItem item1 = new ShopListItem("milk" , 5.9);
ShopListItem item2 = new ShopListItem("bamba" , 4);
ArrayList<ShopListItem> list = new ArrayList<ShopListItem>();
list.add(item1);
list.add(item2);
shopItemAdapter adapter = new shopItemAdapter(this , R.layout.shop_item_row, list);
items.setAdapter(adapter);
}
}
Try it!!!!

Data not showing in static way using listview

I am new to android and i am working on listview. I am trying to show data using listview in xml and adapter in class file. I am working on following 3 files.
First file: 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="com.listpractice.MainActivity" >
<ListView
android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:drawSelectorOnTop="false"
></ListView>
</RelativeLayout>
Second file: row1.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="?android:attr/listPreferredItemHeight" >
<ImageView
android:id="#+id/icon"
android:contentDescription="#string/hello_world"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="10dp"
android:layout_marginEnd="10dp"
android:src="#drawable/ic_launcher"
/>
<TextView
android:id="#+id/firstTextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:layout_toRightOf="#id/icon"
android:layout_toEndOf="#id/icon"
android:textSize="30sp"
android:text="#string/hello_world"
/>
<TextView
android:id="#+id/secondTextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/icon"
android:layout_toEndOf="#id/icon"
android:layout_below="#id/firstTextView"
android:textSize="13sp"
android:text="#string/hello_world"
/>
</RelativeLayout>
Third file: MainActivity.java
package com.listpractice;
import android.app.ListActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
public class MainActivity extends ListActivity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
My Problem : Now i want to show data of row1.xml but i don't have dynamic data. how can i show data using third(.class) file.
check out this link it will help http://androidexample.com/Create_A_Simple_Listview_-_Android_Example/index.php?view=article_discription&aid=65&aaid=90
either you need to create adapter file
public class CustomBaseAdapter extends BaseAdapter{
Context context;
List<RowItem> rowItems;
public CustomBaseAdapter(Context context, List<RowItem> items) {
this.context = context;
this.rowItems = items;
}
/*private view holder class*/
private class ViewHolder {
ImageView imageView;
TextView txtTitle;
//TextView txtDesc;
ImageView imgarrow;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
LayoutInflater mInflater = (LayoutInflater)
context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_item, null);
holder = new ViewHolder();
//holder.txtDesc = (TextView) convertView.findViewById(R.id.desc);
holder.txtTitle = (TextView) convertView.findViewById(R.id.title);
holder.imageView = (ImageView) convertView.findViewById(R.id.icon);
holder.imgarrow=(ImageView)convertView.findViewById(R.id.arrow_icon);
convertView.setTag(holder);
}
else {
holder = (ViewHolder) convertView.getTag();
}
RowItem rowItem = (RowItem) getItem(position);
//holder.txtDesc.setText(rowItem.getDesc());
holder.txtTitle.setText(rowItem.getTitle());
holder.imageView.setImageResource(rowItem.getImageId());
holder.imgarrow.setImageResource(rowItem.getImg());
return convertView;
}
#Override
public int getCount() {
return rowItems.size();
}
#Override
public Object getItem(int position) {
return rowItems.get(position);
}
#Override
public long getItemId(int position) {
return rowItems.indexOf(getItem(position));
}
}
MainActivity
public class MainActivity extends Activity implements OnItemClickListener{
public static final String[] titles = new String[] { "Krish",
"John Cena", "Kane","Roman Reigns"};
public static final Integer[] images = { R.drawable.fourth,R.drawable.second,R.drawable.first,R.drawable.third};
public static final Integer[] imagearow = {R.drawable.arrow,R.drawable.arrow,R.drawable.arrow,R.drawable.arrow };
ListView listView;
List<RowItem> rowItems;
private ImageView btn;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.list_item_home);
//list_travels=(ListView)findViewById(R.id.list_travels);
btn=(ImageView)findViewById(R.id.btnaddhotels);
btn.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View arg0)
{
Intent i=new Intent(HomeScreen.this,Registerhotel_resorts.class);
startActivity(i);
}
});
rowItems = new ArrayList<RowItem>();
for (int i = 0; i < titles.length; i++) {
RowItem item = new RowItem(images[i], titles[i],imagearow[i]);
rowItems.add(item);
}
listView = (ListView) findViewById(R.id.list_hotels);
CustomBaseAdapter adapter = new CustomBaseAdapter(this, rowItems);
listView.setAdapter(adapter);
listView.setOnItemClickListener(this);
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
Toast toast = Toast.makeText(getApplicationContext(),
"Item " + (position + 1) + ": " + rowItems.get(position),
Toast.LENGTH_SHORT);
toast.setGravity(Gravity.BOTTOM|Gravity.CENTER_HORIZONTAL, 0, 0);
toast.show();
Intent i1=new Intent(HomeScreen.this,KrishnaParkResort.class);
startActivity(i1);
}
}
You should read this article on Building Layouts with an Adapter. It has some handy concepts which you will need to get your head around.
The fundamental concept is that you need to link your ListView to an Adapter which populates the rows and adds them to the ListView.
Looking at your row1.xml, it looks like you will need a collection of objects which contain;
An image for icon
String for firstTextView
String for secondTextView
You can build a little snippet to create an array of prepopulated objects for test purposes.
public class YourObject {
private Bitmap icon;
private String text1;
private String text2;
public YourObject(Bitmap icon, String text1, String text2) {
this.icon = icon;
this.text1 = text1;
this.text2 = text2;
}
// GETTERS AND SETTERS
}
Then create a collection of them
List<YourObject> data = new ArrayList<>();
for (int z = 0; z < 5; z++) {
YourObject yourObject = new YourObject(yourIcon, "Text1: " + z, "Text2: " + z);
data.add(yourObject);
}
Once you have this collection, you send it to a your Adapter constructor along with the reference to row1.xml, then follow the guide to populate the rows.

how to insert an image into a listview?

I would like to insert a small image to the right of each item in a listview
basically my app should do so as soon as the user clicks on an item in the list view, the image becomes visible, otherwise it must remain invisible.
below is my activity with its XML
Activity
public class EpisodiActivity extends Activity {
public class ViewModel {
private String url;
private String name;
public ViewModel(String url, String name) {
this.url = url;
this.name = name;
}
public String getUrl() {
return this.url;
}
public void setUrl(String url) {
this.url = url;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public String toString() {
return this.name;
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//creazione fullscreen activity
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.episodi_activity);
String[] episodi = getIntent().getStringArrayExtra("Product");
String[] urls = getIntent().getStringArrayExtra("urls");
ListView mylist = (ListView) findViewById(R.id.listView1);
// And in this loop we create the ViewModel instances from
// the name and url and add them all to a List
List<ViewModel> models = new ArrayList<ViewModel>();
for (int i = 0; i < episodi.length; i++) {
String name = episodi[i];
String url = "No value";
if (i < urls.length) {
url = urls[i];
}
ViewModel model = new ViewModel(url, name);
models.add(model);
}
// Here we create the ArrayAdapter and assign it to the ListView
// We pass the List of ViewModel instances into the ArrayAdapter
final ArrayAdapter<ViewModel> adapter = new ArrayAdapter<ViewModel>(this, android.R.layout.simple_list_item_1, models);
mylist.setAdapter(adapter);
mylist.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View v, int position, long id) {
// Here we get the ViewModel at the given position
ViewModel model = (ViewModel) arg0.getItemAtPosition(position);
// And the url from the ViewModel
String url = model.getUrl();
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
}
});
}
XML
RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ListView
android:id="#+id/listView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_above="#id/pubblicita"
android:cacheColorHint="#ffd700"
android:background="#drawable/sfondobottone" />
I think you want this kind of output in listview
text with image in listview
You can use custom listview . Make a class which extends BaseAdapter class
here is the exmaple that i am using
Your BaseAdapter
import java.util.ArrayList;
import android.content.Context;
import android.graphics.Bitmap;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class FrontListBaseAdapter extends BaseAdapter {
private static ArrayList<FrontDetails> itemDetailsrrayList;
private LayoutInflater l_Inflater;
public FrontListBaseAdapter(Context context, ArrayList<FrontDetails> results) {
itemDetailsrrayList = results;
l_Inflater = LayoutInflater.from(context);
}
public int getCount() {
return itemDetailsrrayList.size();
}
public Object getItem(int position) {
return itemDetailsrrayList.get(position);
}
public long getItemId(int position) {
return position;
}
// get the views in frontview xml file where you have
// define multiple views that will appear in listview each row
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = l_Inflater.inflate(R.layout.frontview, null);
holder = new ViewHolder();
holder.Image = (ImageView) convertView.findViewById(R.id.adminpic1);
holder.MsgType = (TextView) convertView.findViewById(R.id.msgtype1);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.Image.setImageResource(R.drawable.mainlogo); // you can set your setter here
holder.MsgType.setText(itemDetailsrrayList.get(position).getMsgType());
return convertView;
}
// holder view for views
static class ViewHolder {
ImageView Image;
TextView MsgType;
}
}
your FrontDetails class where you will make getters and setters and this class will be used in final ArrayList resultse = new ArrayList();
import android.graphics.Bitmap;
public class FrontDetails {
public int getImage() {
return image;
}
public void setImage(int imageN) {
this.image = imageN;
}
public String getMsgType() {
return MsgType;
}
public void setMsgType(String text) {
this.MsgType = text;
}
private int image;
private String MsgType;
}
your frontview.XML where you put your multiple views that will be in each row or your layout
<?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="100dp"
android:orientation="vertical"
android:layout_margin="10dp" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="80dp" >
<ImageView
android:id="#+id/adminpic1"
android:layout_width="60dp"
android:layout_height="60dp"
android:src="#drawable/ic_launcher" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/msgtype1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="5dp"
android:layout_marginTop="4dp"
android:textSize="1sp"
android:text="MsgType" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
and your listview in xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="#+id/sync"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Sync" />
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="10dp" >
</ListView>
</LinearLayout>
now in your main activity
final ArrayList<FrontDetails> resultse = new ArrayList<FrontDetails>();
FrontListBaseAdapter asdf = new FrontListBaseAdapter(context, resultse);
lv1.setAdapter(new FrontListBaseAdapter(Front.this, resultse));
lv1.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1,
int position, long arg3) {
Object o = lv1.getItemAtPosition(position);
FrontDetails obj_itemDetails = (FrontDetails)o;
Toast.makeText(context, "You have chosen " + ' ' + obj_itemDetails.getMsgType(), Toast.LENGTH_LONG).show();
}
});
EDIT:
From here i learned Custom Listview its a simple exmaple with image
http://www.javasrilankansupport.com/2012/05/android-listview-example-with-image-and.html
http://www.javacodegeeks.com/2012/10/android-listview-example-with-image-and.html
Use custom listview with BaseAdapter
Your Adapter
public class CustomBaseAdapter extends BaseAdapter {
Context context;
List<RowItem> rowItems;
public CustomBaseAdapter(Context context, List<RowItem> items) {
this.context = context;
this.rowItems = items;
}
/*private view holder class*/
private class ViewHolder {
ImageView imageView;
TextView txtTitle;
TextView txtDesc;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
LayoutInflater mInflater = (LayoutInflater)
context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_item, null);
holder = new ViewHolder();
holder.txtDesc = (TextView) convertView.findViewById(R.id.desc);
holder.txtTitle = (TextView) convertView.findViewById(R.id.title);
holder.imageView = (ImageView) convertView.findViewById(R.id.icon);
convertView.setTag(holder);
}
else {
holder = (ViewHolder) convertView.getTag();
}
RowItem rowItem = (RowItem) getItem(position);
holder.txtDesc.setText(rowItem.getDesc());
holder.txtTitle.setText(rowItem.getTitle());
holder.imageView.setImageResource(rowItem.getImageId());
return convertView;
}
#Override
public int getCount() {
return rowItems.size();
}
#Override
public Object getItem(int position) {
return rowItems.get(position);
}
#Override
public long getItemId(int position) {
return rowItems.indexOf(getItem(position));
}
}
Your list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ImageView
android:id="#+id/icon"
android:layout_width="80dp"
android:layout_height="80dp"
android:contentDescription="#string/image"
android:paddingLeft="10dp"
android:paddingRight="10dp" />
<TextView
android:id="#+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#+id/icon"
android:paddingBottom="10dp"
android:textColor="#CC0033"
android:textSize="16dp" />
<TextView
android:id="#+id/desc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/title"
android:layout_toRightOf="#+id/icon"
android:paddingLeft="10dp"
android:textColor="#3399FF"
android:textSize="14dp" />
</RelativeLayout>
Your Single Row item class
public class RowItem {
private int imageId;
private String title;
private String desc;
public RowItem(int imageId, String title, String desc) {
this.imageId = imageId;
this.title = title;
this.desc = desc;
}
public int getImageId() {
return imageId;
}
public void setImageId(int imageId) {
this.imageId = imageId;
}
public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
#Override
public String toString() {
return title + "\n" + desc;
}
}
List view implementation
listView = (ListView) findViewById(R.id.list);
CustomBaseAdapter adapter = new CustomBaseAdapter(this, rowItems);
listView.setAdapter(adapter);
I can give some tips ,but unfortunately couldn't help you by example..
First of all create one custom adapter(extends BaseAdapter) followed by one custom layout..
Here the custom layout contains the textview and one image view(by default invisible) at the right.
Just customize your list view with your adapter and put text inside TextView through get view()..
At last in your listItemClickListener make the image visible by its position.
You can set here on xml like this
android:visibility="visible"
or
android:visibility="invisible"
or
android:visibility="gone"
Java program:
ImageView imgView = (ImageView)findViewById(R.id.custom);
set your ImageView like this
imgView .setVisibility(View.VISIBLE);
imgView .setVisibility(View.INVISIBLE);
imgView .setVisibility(View.GONE);
Difference between INVISIBLE and GONE.
INVISIBLE - The widget will be invisible but space for the widget will be show.
GONE - Both space and widget is invisible.
Now you can hook your setOnItemClickListener()
listview.setOnItemClickListener(new OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> arg0, View arg1,int position, long arg3)
{
imgView .setVisibility(View.VISIBLE);
}
});

Can't find TextView in recursive custom Listview adapter

I created this class called GeoArea, which is suppose to store "Geographical Area" that have children Geographical Areas, this is fairly strait foward:
public class GeoArea {
public String id;
public String name;
public List<GeoArea> subGeoAreas;
public GeoArea parentGeoArea;
public GeoArea(String id) {
this.id = id;
name = id;
subGeoAreas = new LinkedList<GeoArea>();
}
#Override
public String toString() {
return name;
}
}
I have created the following Layout to render it on Android, the idea here is to for each GeoArea to recursively render it self and then it's children GeoArea in a listView:
//layout_geo_area.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/txtGeoAreaName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:gravity="left"
android:text="Geo Area Name"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ListView
android:id="#+id/listViewChildGeoAreas"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/txtGeoAreaName"
android:gravity="left" >
</ListView>
</RelativeLayout>
This is my adapter I created for GeoArea to be displayed in a listView:
public class AdapterGeoArea extends ArrayAdapter<GeoArea>{
private ArrayList<GeoArea> _myGeoArea;
private Context _myContext;
LayoutInflater _inflater;
public AdapterGeoArea(Context context, ArrayList<GeoArea> myGeoArea) {
super(context, 0, myGeoArea);
_myGeoArea = myGeoArea;
_inflater = LayoutInflater.from(context);
_myContext = context;
}
public int getCount() {
return _myGeoArea.size();
}
public View getView(int position, View convertView, ViewGroup parent) {
GeoAreaLayoutHolder holder;
if (convertView == null) {
convertView = _inflater.inflate(R.layout.layout_geo_area,parent,false);
holder = new GeoAreaLayoutHolder();
holder.txtGeoAreaName = (TextView)convertView.findViewById(R.id.txtGeoAreaName);
holder.txtGeoAreaName.setTag(convertView);
holder.listViewChildGeoAreas = (ListView)convertView.findViewById(R.id.listViewChildGeoAreas);
holder.listViewChildGeoAreas.setTag(convertView);
} else {
holder = (GeoAreaLayoutHolder) convertView.getTag();
}
GeoArea curGeoArea = _myGeoArea.get(position);
holder.txtGeoAreaName.setText(curGeoArea.name);
if(curGeoArea.subGeoAreas.size()>0){
ArrayList<GeoArea> testList = new ArrayList<GeoArea>();
AdapterGeoArea adapter = new AdapterGeoArea(_myContext, testList);
for(GeoArea childGeoArea:curGeoArea.subGeoAreas){
testList.add(childGeoArea);
}
holder.listViewChildGeoAreas.setAdapter(adapter);
}
return convertView;
}
static class GeoAreaLayoutHolder {
public TextView txtGeoAreaName;
public ListView listViewChildGeoAreas;
}
}
And here is my Activity that I am using to set it all up:
public class ActivityGeoAreas extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_geo_area);
GeoArea.searchTerm = "Bar & Grill";
GeoArea torontoArea = new GeoArea("cityOfToronto");
ArrayList<GeoArea> testList = new ArrayList<GeoArea>();
testList.add(torontoArea);
AdapterGeoArea adapter = new AdapterGeoArea(this, testList);
ListView lv = (ListView) findViewById(R.id.listViewChildGeoAreas);
lv.setAdapter(adapter);
}
}
When I try to run it, I get the error nullPointerException on the line:
holder.txtGeoAreaName.setText(curGeoArea.name);
What am I doing wrong?
You may want to check ExpandableListView may suit your needs better
http://developer.android.com/reference/android/widget/ExpandableListView.html
An example # http://www.androidhive.info/2013/07/android-expandable-list-view-tutorial/
Continuing from my previous answer to your question ( i though that solved your problem)
To display just name in your listview
list_row.xml // this is the layout with textview to be inflated in getView.
Each row will have textview
<?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/textGeoArea"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="14dp"
android:text="Choose Area"
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>
layout_geo_area.xml // with only listview no textview
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ListView
android:id="#+id/listViewChildGeoAreas"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:gravity="left" >
</ListView>
</RelativeLayout>
Now your adapter class
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.list_row,parent,false);
// inflate list_row.xml with textview
holder = new ViewHolder();
holder.tv = (TextView)convertView.findViewById(R.id.textGeoArea);
holder.setTag(convertView);
}
else {
holder = (ViewHolder) convertView.getTag();
}
GeoArea curGeoArea = _myGeoArea.get(position);
holder.tv.setText(curGeoArea.name);
return convertView;
}
static class ViewHolder // use a view holder for smooth scrolling an performance
{
TextView tv;
}
You have a custom adapter.
public class AdapterGeoArea extends ArrayAdapter<GeoArea>{
Now you set the adapter to listview like below
AdapterGeoArea adapter = new AdapterGeoArea(this, testList);
ListView lv = (ListView) findViewById(R.id.listViewChildGeoAreas);
lv.setAdapter(adapter);
So why do you need the below. remove these
if(curGeoArea.subGeoAreas.size()>0){
ArrayList<GeoArea> testList = new ArrayList<GeoArea>();
AdapterGeoArea adapter = new AdapterGeoArea(_myContext, testList);
for(GeoArea childGeoArea:curGeoArea.subGeoAreas){
testList.add(childGeoArea);
}
holder.listViewChildGeoAreas.setAdapter(adapter);

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