I have a special class, a custom adapter for my ListView and I need to get some data from another Activity. But my implementation of the method GetIntent()GetExtras() isn't working. What is wrong?
Here is my custom adapter code:
public class CustomAdapter extends ArrayAdapter<String> {
int myColor,myWidth;
private final Context context;
private final String[] values;
public CustomAdapter(Context context, String[] values) {
super(context, R.layout.list_item, values);
this.context = context;
this.values = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// return super.getView(position, convertView, parent);
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView = inflater.inflate(R.layout.list_item, parent, false);
TextView textView = (TextView) rowView.findViewById(R.id.ColorTextButton);
ImageView imageView = (ImageView) rowView.findViewById(R.id.imageViewIcon);
TextView textView1 = (TextView) rowView.findViewById(R.id.HelpButton);
textView.setText(values[position]);
String s = values[position];
System.out.println(s);
if (s.equals("Monday")) {
imageView.setImageResource(R.drawable.arrow2);
textView.setBackgroundColor(Color.YELLOW);
} else if (s.equals("Wednesday")) {
imageView.setImageResource(R.drawable.arrow2);
textView1.setBackgroundColor(Color.GREEN);
} else if (s.equals("Friday")) {
imageView.setImageResource(R.drawable.arrow2);
} else {
imageView.setImageResource(R.drawable.arrow);
}
return rowView;
}
}
If you want the data to be accessable From a few activities you should think about use a singleton data Class. so in stead of trying to get pass the data from your adapter to a second activity both the adaper and the Activity use the same method to get the data class
public class DataProvider {
private static DataProvider instance;
public static DataProvider getInstance()
{
if(null == instance){instance = new DataProvider();}
return instnace;
}
public String[] getObjects(){
return this.myStringArray;
}
// add more methods in here to retrieve and count your data as you need
}
then in your Activity you can
// somewhere
myStingArrayInMyActivity = DataProvider.getInstance().getObjects()
also in you adapter
you can do
public class CustomAdapter extends ArrayAdapter<String> {
int myColor,myWidth;
private final Context context;
private final String[] values;
public CustomAdapter(Context context, String[] values) {
super(context, R.layout.list_item, values);
this.context = context;
this.values = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// your code
textView.setText(DataProvider.getInstance.getObjects[position]);
String s = DataProvider.getInstance.getObjects[position];
/// your code
return rowView;
}
}
Related
im working on a tank-game. in this tank-game i want to display the items which the player can use(shild,firework,atombomb)i want to realise this with a listview and a arraya-dapter. i've made a customized ArrayAdapter like i found it in much answers but it didnt work. The list is not there after i set the adapter. After i debug the project i came to the conclusion that the getView-method in the adapter class isnt called
why?
This is my adapter class
public class Adapter extends ArrayAdapter {
private Context context;
private ArrayList<Item> items;
public Adapter(#NonNull Context context, ArrayList<Item> items) {
super(context, R.layout.listview_item);
this.context = context;
this.items = items;
}
#NonNull
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder = new ViewHolder();
if(convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.listview_item, parent, false);
viewHolder.imageView = convertView.findViewById(R.id.imageView);
convertView.setTag(viewHolder);
}else{
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.imageView.setImageBitmap(items.get(position).getImageView());
return convertView;
}
static class ViewHolder{
ImageView imageView;
}
}
Here i want to set the adapter
public void createList(ListView listView){
Adapter adapter = new Adapter(context,tanks.get(currentTank).getItems());
listView.setAdapter(adapter);
}
public Adapter(#NonNull Context context, ArrayList<Item> items) {
super(context, R.layout.listview_item);
this.context = context;
this.items = items;
}
Instead of this try this :
public MyCustomListAdapter(Context context,int resource, ArrayList<Item> items)
{
super(context,resource,list);
this.context= context;
this.resource=resource;
this.list=list;
}
Also in your main class write this code:
Adapter adapter = new Adapter(context,R.layout.<Thename of your layout>,tanks.get(currentTank).getItems());
I'm doing an app that uses BaseAdapter to see installed app in an Android device.
In this Listview there are more items, but in the adapter there are only two, and from the second (the package name) I get the other ones
I'm searching a way to sort the items of this adapter for an item that is in the listview, but not in the adapter. Here there is my code:
class AppsAdapter extends BaseAdapter{
private Context mContext;
private List<Pair<String, List<String>>> mAppsWithPermission;
AppsAdapter(Context context, List<Pair<String, List<String>>> appsWithPermission) {
mContext = context;
mAppsWithPermission = appsWithPermission;
}
static class ViewHolder {
TextView appName;
TextView appPermissions;
ImageView appIcon;
TextView Lines;
}
#Override
public int getCount() {
return mAppsWithPermission.size();
}
#Override
public Object getItem(int position) {
return mAppsWithPermission.get(position);
}
#Override
public long getItemId(int position) {
return mAppsWithPermission.get(position).hashCode();
}
#RequiresApi(api = Build.VERSION_CODES.N)
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.list_item, parent, false);
holder = new ViewHolder();
holder.appName = convertView.findViewById(R.id.list_item_appname);
holder.appPermissions = convertView.findViewById(R.id.list_item_apppermissions);
holder.appIcon = convertView.findViewById(R.id.list_item_appicon);
holder.Lines = convertView.findViewById(R.id.list_item_lines);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
final Pair<String, List<String>> item = mAppsWithPermission.get(position);
final PackageManager packageManager = mContext.getPackageManager();
String mAppPer = item.second.toString();
int lineCount = holder.appPermissions.getLineCount();
Log.v("LINE_NUMBERS", lineCount+"");
String strI = Integer.toString(lineCount);
holder.Lines.setText(strI);
if (mAppPer.matches("")) {
holder.Lines.setText("0");
}
});
return convertView;
}
}
When you see "item.second" it's the package name.
As you can think, I'm trying to sort the entire adapter for the descendant value of holder.lines (so StrI).
This is a different question from the others that talks about sorting an adapter, because I want to sort the adapter for an external value.
If you need further informations, you've just to ask me.
in my android application I am displaying the contact list of phone in a list view and a check box in each row for selecting contacts. But when I am selecting a particular row about tenth row is also getting selected automatically. I am giving my code below, if any one knows please help..
public class ContactsAdapter extends BaseAdapter
{
private Context context;
private ArrayList<Contact> contacts;
public ContactsAdapter(Context context, ArrayList<Contact> contacts)
{
this.context = context;
this.contacts = contacts;
}
public View getView(final int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View gridView;
final ViewHolder mHolder;
if (convertView == null)
{
// gridView = new View(context);
// get layout from mobile.xml
//gridView = inflater.inflate(R.layout.contact, null);
convertView = inflater.inflate(R.layout.contact, null);
mHolder = new ViewHolder();
mHolder.textName =(TextView) convertView.findViewById(R.id.name);
mHolder.textMobile =(TextView) convertView.findViewById(R.id.mobile);
mHolder.textSelector =(CheckBox) convertView.findViewById(R.id.selected);
convertView.setTag(mHolder);
));
}
else
{
mHolder = (ViewHolder) convertView.getTag();
mHolder.textSelector.setOnCheckedChangeListener(null);
}
mHolder.textMobile.setText(contacts.get(position).getMobile());
mHolder.textName.setText(contacts.get(position).getName());
mHolder.textSelector.setFocusable(false);
return convertView;
}
private class ViewHolder {
private TextView textMobile,textName;
private CheckBox textSelector;
}
#Override
public int getCount() {
return contacts.size();
}
#Override
public Object getItem(int position) {
return null;
}
#Override
public long getItemId(int position) {
return 0;
}
}
Well Thats because ViewHolder will recycle the Views everytime you Scroll
i suggest you to Use onCLick on ListItem instead checkbox
To overcome this Declare a SparseBooleanArray
SparseBooleanArray sba=new SparseBooleanArray();//this should be global
Then set the items checked state as soon as you render it
mHolder.textSelector =(CheckBox) convertView.findViewById(R.id.selected);
mHolder.textSelector.setChecked(sba.get(position));
Then write a onClickListener to you convertView and check it manually
convertView.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
mHolder.textSelector.setChecked(isChecked);
sba.put(position,isChecked); //storing the state
}
}
);
**Well Now the sba has list items checked and you can use that for further Actions**
# Jocheved... edit your code like this...
public class ContactsAdapter extends BaseAdapter
{
private Context context;
private ArrayList<Contact> contacts;
SparseBooleanArray sba=new SparseBooleanArray();
public ContactsAdapter(Context context, ArrayList<Contact> contacts)
{
this.context = context;
this.contacts = contacts;
}
public View getView(final int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
final ViewHolder mHolder;
if (convertView == null)
{
convertView = inflater.inflate(R.layout.contact, null);
mHolder = new ViewHolder();
mHolder.textName =(TextView) convertView.findViewById(R.id.name);
mHolder.textMobile =(TextView) convertView.findViewById(R.id.mobile);
mHolder.textSelector =(CheckBox) convertView.findViewById(R.id.selected);
convertView.setTag(mHolder);
}
else
{
mHolder = (ViewHolder) convertView.getTag();
}
mHolder.textMobile.setText(contacts.get(position).getMobile());
mHolder.textName.setText(contacts.get(position).getName());
mHolder.textName.setSelected(true);
mHolder.textSelector.setChecked(sba.get(position));
mHolder.textSelector.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v) {
if(mHolder.textSelector.isChecked())
{
sba.put(position, true);
}
else
{
sba.put(position, false);
}
}
});
return convertView;
}
private class ViewHolder
{
private TextView textMobile,textName;
private CheckBox textSelector;
}
#Override
public int getCount() {
return contacts.size();
}
#Override
public Object getItem(int position) {
return null;
}
#Override
public long getItemId(int position) {
return 0;
}
}
The current project I have includes a ListView with a Custom Adapter. However, I am now interested in adding multiple types of views to my ListView but after several attempts I have been unable to add the two sources of code together to successfully integrate them.
Article on ListView with multiple views: ListView Article for multiple views
The custom adapter in my current code retrieves the data from another class called getData which is referenced by "data".
Code from article (ListView with multiple views):
public class MultipleItemsList extends ListActivity {
private MyCustomAdapter mAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mAdapter = new MyCustomAdapter();
for (int i = 1; i < 50; i++) {
mAdapter.addItem("item " + i);
if (i % 4 == 0) {
mAdapter.addSeparatorItem("separator " + i);
}
}
setListAdapter(mAdapter);
}
private class MyCustomAdapter extends BaseAdapter {
private static final int TYPE_ITEM = 0;
private static final int TYPE_SEPARATOR = 1;
private static final int TYPE_MAX_COUNT = TYPE_SEPARATOR + 1;
private ArrayList mData = new ArrayList();
private LayoutInflater mInflater;
private TreeSet mSeparatorsSet = new TreeSet();
public MyCustomAdapter() {
mInflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
public void addItem(final String item) {
mData.add(item);
notifyDataSetChanged();
}
public void addSeparatorItem(final String item) {
mData.add(item);
// save separator position
mSeparatorsSet.add(mData.size() - 1);
notifyDataSetChanged();
}
#Override
public int getItemViewType(int position) {
return mSeparatorsSet.contains(position) ? TYPE_SEPARATOR : TYPE_ITEM;
}
#Override
public int getViewTypeCount() {
return TYPE_MAX_COUNT;
}
#Override
public int getCount() {
return mData.size();
}
#Override
public String getItem(int position) {
return mData.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
int type = getItemViewType(position);
System.out.println("getView " + position + " " + convertView + " type = " + type);
if (convertView == null) {
holder = new ViewHolder();
switch (type) {
case TYPE_ITEM:
convertView = mInflater.inflate(R.layout.item1, null);
holder.textView = (TextView)convertView.findViewById(R.id.text);
break;
case TYPE_SEPARATOR:
convertView = mInflater.inflate(R.layout.item2, null);
holder.textView = (TextView)convertView.findViewById(R.id.textSeparator);
break;
}
convertView.setTag(holder);
} else {
holder = (ViewHolder)convertView.getTag();
}
holder.textView.setText(mData.get(position));
return convertView;
}
}
public static class ViewHolder {
public TextView textView;
}
}
Current code (ListView with custom adapter):
FragmentA.java
package com.example.newsapp;
public class FragmentA extends Fragment{
getData data = getData.getMyData();
public Integer ArticleID;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View V = inflater.inflate(R.layout.fragment_a, container, false);
ListView listView = (ListView)V.findViewById(R.id.list)
CustomList adapter = new
CustomList(getActivity(), data.Headline.toArray(new String[data.Headline.size()]), data.Description.toArray(new String[data.Description.size()]), data.BitmapList.toArray(new Bitmap[data.BitmapList.size()]), data.ArticleID.toArray(new Integer[data.ArticleID.size()]));
listView.setAdapter(adapter);
listView.setOnItemClickListener(this); //Removed on click item event code.
return V;
}
CustomList.java
package com.example.newsapp;
public class CustomList extends ArrayAdapter<String>{
private final Activity context;
private final String[] titleId;
private final String[] descriptionId;
private final Bitmap[] pictureid;
public CustomList(Activity context,
String[] Headline, String[] Description, Bitmap[] BitmapList, Integer[] ArticleID) {
super(context, R.layout.single_row, Headline);
this.context = context;
this.titleId = Headline;
this.descriptionId = Description;
this.pictureid = BitmapList;
}
#Override
public View getView(int position, View view, ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
View rowView= inflater.inflate(R.layout.single_row, null, true);
TextView txtTitle = (TextView) rowView.findViewById(R.id.tvTitle);
TextView txtDescription = (TextView) rowView.findViewById(R.id.tvDescription);
ImageView imageView = (ImageView) rowView.findViewById(R.id.ivIcon);
txtTitle.setText(titleId[position]);
txtDescription.setText(descriptionId[position]);
imageView.setImageBitmap(pictureid[position]);
return rowView;
}
}
Edit:
public class CustomList extends ArrayAdapter<String>{
private final Activity context;
private final String[] titleId;
private final String[] descriptionId;
private final Bitmap[] pictureid;
public CustomList(Activity context,
String[] Headline, String[] Description, Bitmap[] BitmapList, Integer[] ArticleID) {
super(context, R.layout.single_row, Headline);
this.context = context;
this.titleId = Headline;
this.descriptionId = Description;
this.pictureid = BitmapList;
}
#Override
public View getView(int position, View view, ViewGroup parent) {
int viewType = getItemViewType(position);
View rowView = null;
switch(viewType) {
case 0:
LayoutInflater inflater = context.getLayoutInflater();
rowView= inflater.inflate(R.layout.single_row, null, true);
TextView txtTitle = (TextView) rowView.findViewById(R.id.tvTitle);
TextView txtDescription = (TextView) rowView.findViewById(R.id.tvDescription);
ImageView imageView = (ImageView) rowView.findViewById(R.id.ivIcon);
txtTitle.setText(titleId[position]);
txtDescription.setText(descriptionId[position]);
imageView.setImageBitmap(pictureid[position]);
case 1:
LayoutInflater inflater2 = context.getLayoutInflater();
rowView= inflater2.inflate(R.layout.single_row_loadmore, null, true);
}
return rowView;
}
#Override
public int getViewTypeCount() {
return 2; // TODO make this a static final
}
#Override
public int getItemViewType(int position) {
return position % 2; // 0 or 1
}
}
First, a bit of an aside: you should create a class that encapsulates a headline, description, etc. and use an array/collection of those objects to back your adapter. It will be far easier than managing many disparate arrays of things, especially if one day you decide you need another attribute of an Article (its category, for example).
class Article {
int id;
String headline;
String description;
Bitmap picture;
}
With regard to your ListView, the magic happens in the methods getItemViewType() and getViewTypeCount(). In getViewTypeCount() you return the maximum number of row types -- the article you posted uses two row types and so returns 2. In getItemViewType() you return a value between zero and (viewTypeCount - 1) -- in the article, his implementation can return 0 or 1 because his viewTypeCount is 2.
How you decide which row type applies to each item is entirely up to you. If, for example, you wanted to simply alternate view types on every row, you can do this:
#Override
public int getViewTypeCount() {
return 2; // TODO make this a static final
}
#Override
public int getItemViewType(int position) {
return position % 2; // 0 or 1
}
In other applications you would probably inspect the item at the given position to help you determine what should be returned in getItemViewtype().
The reason this functionality exists is that getView() provides a parameter (called convertView) that is a row which has been recycled. In order to give you an appropriate convertView, ListView needs to first know what row type it was. When you want to implement getView() for an adapter with multiple row types, it generally looks something like this:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
int viewType = getItemViewType(position);
switch(viewType) {
case 0:
return setUpOneViewType(position, convertView, parent);
case 1:
return setUpAnotherViewType(position, convertView, parent);
}
}
Note the cases for the switch statement correspond to the possible values that can be returned from getItemViewType(). These could be static final members.
I highly suggest watching The World of ListView. That video covers this topic as well as how to properly use convertView in your adapter implementation.
why in every example i see that extends the class ArrayAdapter it overrides the constructor that accepts T[] objects and references its own private variable to that and uses the referenced variable in the override of getView?
how can this be dynamic adding of objects?
will values be updated when a new item is added to the ArrayAdapter using add method?
can i instead of implementing my own adapter just use addheaderview in listview?
public class MySimpleArrayAdapter extends ArrayAdapter<String> {
private final Context context;
private final String[] values;
public MySimpleArrayAdapter(Context context, String[] values) {
super(context, R.layout.rowlayout, values);
this.context = context;
this.values = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView = inflater.inflate(R.layout.rowlayout, parent, false);
TextView textView = (TextView) rowView.findViewById(R.id.label);
ImageView imageView = (ImageView) rowView.findViewById(R.id.icon);
textView.setText(values[position]);
// change the icon for Windows and iPhone
String s = values[position];
if (s.startsWith("iPhone")) {
imageView.setImageResource(R.drawable.no);
} else {
imageView.setImageResource(R.drawable.ok);
}
return rowView;
}
}