I have a RecyclerView. In it, the items have a standard layout - one TextView and one ProgressBar.
Items are added to the recyclerview at runtime.
Whenever an Item is added, an AsyncTask is started which updates the ProgressBar.
The AsynTask holds a reference to the ProgressBar object from the RecyclerView Adapter.
The problem occurs when there are too many items in the recycler view.
I know the RecyclerView recycles any old views and thus want a way around that atleast for the progressbars.
What would be the ideal way to implement this?
Following is an excerpt from the Adapter
public class RecViewAdapter extends
RecyclerView.Adapter<RecViewAdapter.ViewHolder> {
Context mContext;
List<String> mRunns;
static ExecutorService mExec;
static HashSet<Integer> mProcessed = new HashSet<>();
public RecViewAdapter(Context context, List<String> runns) {
mContext = context;
mRunns = runns;
mExec = Executors.newFixedThreadPool(1);
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.runnabel_item, viewGroup,
false);
ViewHolder vh = new ViewHolder(v);
return vh;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
holder.runnName.setText(mRunns.get(position));
if (!mProcessed.contains(position)) {
new ProgressTask(holder.pBar, position).executeOnExecutor(mExec, null);
mProcessed.add(position);
}
}
#Override
public int getItemCount() {
return mRunns.size();
}
public static class ViewHolder extends RecyclerView.ViewHolder {
TextView runnName;
ProgressBar pBar;
public ViewHolder(View view) {
super(view);
runnName = (TextView) view.findViewById(R.id.textView);
pBar = (ProgressBar) view.findViewById(R.id.progressBar);
pBar.setIndeterminate(false);
pBar.setMax(100);
pBar.setProgress(0);
}
}
}
Also, I'm adding items to the RecyclerView using notifydatasetchanged.
You can simply use "findViewHolderForAdapterPosition" method of recycler view and you will get a viewHolder object from that then typecast that viewHolder into your adapter viewholder, so you can directly access your viewholder's views, ( in this case we access progressBar)
following is the sample code for kotlin
/**
* update progress bar in recycler view
* get viewHolder from position and progress bar from that viewHolder
* we are rapidly updating progressbar so we did't use notify method as it always update whole row instead of only progress bar
* #param position : position of list cell
* #param progress : new progress value
*/
private fun updateDownloadProgressBar(position :Int, progress:Int)
{
val viewHolder = recyclerViewDownload.findViewHolderForAdapterPosition(position)
(viewHolder as ViewHolderDownload).progressBarDownload.progress=progress
}
A little late, but I found a way to get it working.
My recyclerview contains a large number viewholders and only one of the viewholders have a progress bar. I have an sqlite database in which I maintain identifiers which I use to sync between my service and activity (to identify which views in the recyclerview need updating).
Depending on your implementation, you will have to find a way to identify which broadcast event corresponds to which adapter item. I have given a simplified version of what I have done below.
Model for Progress Bar:
class ProgressModel{
String progressId;
int progress = 0;
}
public int getProgress(){
return progress;
}
ViewHolder:
public class ProgressViewHolder extends RecyclerView.ViewHolder {
private ProgressBar mProgressBar;
public ProgressViewHolder(View itemView) {
mProgressBar = (ProgressBar) itemView.findViewById(R.id.mProgressBar);
}
public ProgressBar getProgressBar() {
return mProgressBar;
}
}
In the recyclerview adapter,
#Override
public void onBindViewHolder(ProgressViewHolder holder, int position) {
ProgressModel item = mData.get(position);
int progress = item.getProgress();
if (progress > 0) {
ProgressBar downloadProgress = holder.getProgressBar();
if (downloadProgress.isIndeterminate()) {
downloadProgress.setIndeterminate(false);
}
downloadProgress.setProgress(progress);
}
}
public void refresh(position, ProgressModel item){
mData.set(position, item);
notifyItemChanged(position);
}
In the Activity which implements populates the view, create a static instance of itself and pass it to the BroadcastReceiver. It took me quite a while to figure out that the static instance is required, otherwise the view doesn't get changed even though I call notifyItemchanged().
public class MainActivity extends Activity{
private static MainActivity instance;
private MyReceiver mReceiver;
private MyAdapter mAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
instance = this;
mReceiver = new MyReceiver(instance);
//TODO: Initialize adapter with data and set to recyclerview
}
public void update(Intent intent){
ProgressModel model = new ProgressModel ();
//TODO: set progress detail from intent to model and get position from progressId
instance.mAdapter.refresh(position,model);
}
private static class MyReceiver extends BroadcastReceiver {
MainActivity activity;
public DownloadReceiver(MainActivity activity) {
this.activity = activity;
}
#Override
public void onReceive(Context context, Intent intent) {
//pass intent with progress details to activity
activity.update(intent);
}
}
}
Hope this helps.
Those who are new to Android dev and only know java might get confused of above codes given by #Mayank Sharma Which works excellent, I am giving the java version of his answer:
void updateProgress(int position, int progress)
{
MyAdapter.MyHolder mHolder =
(MyAdapter.MyHolder) myRecyclerView.findViewHolderForAdapterPosition(position);
mHolder.customProgress.setProgress(progress);
}
create this above method inside your activity where you have recycler view that contains progress bar and call this method whenever you want some changes in your progress bar.
Related
I have a fragment Users which has 3 other fragments in it (tabs). For one tab ( called Friends2Fragment ) I made a recycler View and made an adapter for it. In each item of RecyclerView I have a button "Add friend" and I want to call it from Friends2Fragment, not to call it from the adapter because I can't use Firestore Database properly.
RecyclerViewInterface:
public interface RecyclerViewInterface {
void onItemClick(int position, String button_pressed);
}
Friends2Fragment.java :
public void onStart(){
super.onStart();
recyclerView = (RecyclerView) v.findViewById(R.id.recycler);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
friendslist = new ArrayList<>();
myAdapter = new MyAdapter(friendslist,v.getContext());
recyclerView.setAdapter(myAdapter);
------ Firestore operations ------
}
#Override
public void onItemClick(int position, String button_pressed) {
switch ( button_pressed ){
case "ADD_FRIEND":
Log.d(TAG, "item clicked: " + friendslist.get(position).username);
}
}
MyAdapter.java :
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.myViewHolder> {
Context context;
public ArrayList<User> userArrayList;
public MyAdapter(ArrayList<User> userArrayList, Context context) {
this.userArrayList = userArrayList;
this.context = context;
}
public Context getContext() {
return context;
}
public ArrayList<User> getUserArrayList() {
return userArrayList;
}
#NonNull
#Override
public MyAdapter.myViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, parent, false);
MyAdapter.myViewHolder myViewHolder = new MyAdapter.myViewHolder(v);
myViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
((Friends2Fragment)context).onItemClick(myViewHolder.getAdapterPosition(),"ADD_FRIEND");
}
});
return myViewHolder;
}
#Override
public void onBindViewHolder(#NonNull MyAdapter.myViewHolder holder, int position) {
User user = userArrayList.get(position);
holder.usernamerecycle.setText(user.username);
}
#Override
public int getItemCount() {
return userArrayList.size();
}
public void filterList(List<User> filteredList){
userArrayList = (ArrayList<User>) filteredList;
notifyDataSetChanged();
}
public class myViewHolder extends RecyclerView.ViewHolder{
TextView usernamerecycle;
Button addbutton;
View rootview;
public myViewHolder(#NonNull View itemView) {
super(itemView);
rootview = itemView;
usernamerecycle = itemView.findViewById(R.id.usernamerecycler);
addbutton = itemView.findViewById(R.id.addfriendbutton);
}
}
}
The problem is at this line : ((Friends2Fragment)context).onItemClick(myViewHolder.getAdapterPosition(),"ADD_FRIEND"); in onCreateViewHolder method in MyAdapter.
I have this error : Inconvertible types; cannot cast 'android.content.Context' to 'com.example.birthday.Fragments.Friends2Fragment'
Please help me ..
A Fragment isn't a Context (that's not one of its supertypes) so that cast is impossible, that's why you're getting the error.
I think you should organise it like this: your Adapter holds a bunch of User objects, right? It displays those, and you have a click listener on each ViewHolder that knows which index in the User list it's currently displaying, and it wants to inform some listener when it's clicked. That index is an internal detail really, it would make more sense to look up the actual User, and provide that to the listener.
The simplest way is to just provide your fragment as a listener. First store it in your adapter:
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.myViewHolder> {
// store a reference to your fragment
private Friends2Fragment listener;
// add a function to provide that fragment
public void setListener(Friends2Fragment: listener) {
this.listener = listener
}
...
public MyAdapter.myViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
...
myViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (listener != null) {
// look up the actual user
User user = userArrayList.get(myViewHolder.getAdapterPosition());
// call a function on your fragment
listener.onItemClick(user, "ADD_FRIEND");
}
}
});
}
Then add the callback function your adapter uses, and also set your fragment on the adapter as a listener:
// Friends2Fragment
// You should REALLY be doing this in onViewCreated or something, so this setup happens once.
// You're losing all your state by creating a new adapter whenever the user returns to the app
public void onStart(){
...
myAdapter = new MyAdapter(friendslist,v.getContext());
// set the fragment as the listener
myAdapter.setListener(this);
recyclerView.setAdapter(myAdapter);
}
// now add the function the adapter calls
private void onItemClick(User user, String someString) {
// handle the clicked user
}
A better way is to create an interface with all the events that need to be handled, and make your Fragment implement those. It breaks the hard association with the Fragment since you could pass any object that implements those functions, and it's also clearer because the interface kinda documents all the data the adapter produces, and that a listener needs to be able to handle. Something like this:
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.myViewHolder> {
// the listener is now something that implements the Callbacks interface
private Callbacks listener;
...
// nesting it inside MyAdapter makes the path MyAdapter.Callbacks, which makes it clear
// exactly what it is and what it relates to, and kinda gives the Adapter "ownership"
interface Callbacks {
void addFriend(User user)
}
And then you just make the Fragment implement that interface
public class Friends2Fragment() extends Fragment implements MyAdapter.Callbacks {
...
// implement all the callbacks you need to handle
override public void addFriend(User user) {
// do the thing
}
// set it in the same way, since this Fragment implements MyAdapter.Callbacks
myAdapter.setListener(this);
Which is a bit neater and cleaner, I think - but slightly more work. Also if you notice, I renamed the callback function from the generic handleItemClick to the more specific addFriend - so instead of having to pass a String saying what kind of click it is, you just have a function for each event you want to handle, and you can name them appropriately
I am creating an AlertDialog custom class, called ActionDialog, which will contains a RecyclerView containing Buttons. I have a List of Button that I populate in the custom class ActionDialog (for now i just populate with useless Button just to try to use it, except one which I create in another class).
The problem is that when i create the AlertDialog, all buttons are showing empty, they are showed but with no text/no clicklistener (as you can see in the image below).
(I have added a custom ActionListener to a Button in another class and then give it as parameter in ActionDialog class. Will it lose the ActionListener?)
Here is the result.
I will leave here my ActionDialog class code, and the adapter class.
This is ActionDialog class:
public class ActionDialog extends AlertDialog{
private RecyclerView mRecyclerView;
private RecyclerView.Adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
private Button actionButtons;
private List<Button> buttons;
private Activity context;
public ActionDialog(#NonNull Activity context, Button actionButtons) {
super(context);
this.context = context;
this.actionButtons = actionButtons;
buttons = new ArrayList<>();
initButton();
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//requestWindowFeature(Window.FEATURE_NO_TITLE);
}
private void initButton(){
initZoneButton();
//TODO init all buttons
Button b1 = new Button(context);
b1.setText("ExampleButton1");
Button b2 = new Button(context);
b2.setText("ExampleButton2");
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String a;
}
});
buttons.add(b1);
buttons.add(b2);
}
private void initZoneButton(){
buttons.add(actionButtons); //this button is created in another class and give as parameter in this class
}
public void createDialog(){
Builder mBuilder = new Builder(context);
View view = context.getLayoutInflater().inflate(R.layout.dialog_actionbuttons_layout, null);
mRecyclerView = view.findViewById(R.id.dialog_actionbuttons_rv);
mRecyclerView.setHasFixedSize(true);
mLayoutManager = new LinearLayoutManager(context);
mRecyclerView.setLayoutManager(mLayoutManager);
mAdapter = new ActionButtonsAdapter(buttons);
mRecyclerView.setAdapter(mAdapter);
mBuilder.setView(view);
mBuilder.create().show();
}
}
Here is the RecyclerView adapter class:
public class ActionButtonsAdapter extends RecyclerView.Adapter<ActionButtonsAdapter.ViewHolder>{
private List<Button> dataButtons;
static class ViewHolder extends RecyclerView.ViewHolder {
Button actionButton;
ViewHolder(View v) {
super(v);
actionButton = v.findViewById(R.id.action_button_rv);
}
}
public ActionButtonsAdapter(List<Button> dataButtons){
this.dataButtons = dataButtons;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
holder.actionButton = dataButtons.get(position);
//i think the problem is here, maybe
}
#Override
public ActionButtonsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_actionbutton_layout, parent, false);
return new ViewHolder(v);
}
#Override
public int getItemCount() {
return dataButtons.size();
}
}
I think in the onBindViewHolder method you should do what ever you want to do with your button.
Also there is no need for the list of buttons here. Make a list the data you need to be held in the Buttons RecyclerView.
I have a RecyclerView that will display Genres for restaurants lets say, So I will create a List of strings to hold these genres names (chickens, meats, etc,..)
Setting its text
holder.actionButton.setText(// Make use of position here);
Or Click Listeners.
Update
You can check google samples for recyclerview here
#Override
public void onBindViewHolder(ViewHolder viewHolder, final int position) {
Log.d(TAG, "Element " + position + " set.");
// Get element from your dataset at this position and replace the contents of the view
// with that element
viewHolder.getTextView().setText(mDataSet[position]);
}
wheres mDataset is Array of Strings.
Actually I am going to ask more than one question here. Don't ban me, please, just read a full story. Let's begin. So I need to create an activity or fragment (it doesn't matter) with to parts (views) inside (top and bottom). Inside the bottom part dynamically loads buttons (sometimes 2, sometimes 30), there is a click listener on them. When a user clicks on a button, the button appears on the top part (view) and disappears on the bottom view. The buttons on the top view also have click listener and if a user clicks on a button it appears on the bottom view and disappears on a top. So this is a task. I thought how to implement it. The simplest solution that I created is: two views are recycler views with two adapters. Mm, probably it is not the best solution, I am pretty sure of it. I could implement two adapters, but I can't implement the click listener for my second adapter. It doesn't work!? I don't like this way for two reasons: 1. both adapters are the same; 2. I can't use click adapter for second adapter. Below you can find my code.
My adapter - standard adapter:
public class KeyboardAdapter extends RecyclerView.Adapter<KeyboardAdapter.KeyboardAdapterViewHolder> {
private List<String> values;
/*
* An on-click handler that we've defined to make it easy for an Activity to interface with
* our RecyclerView
*/
private final KeyboardAdapterOnClickHandler mClickHandler;
/**
* The interface that receives onClick messages.
*/
public interface KeyboardAdapterOnClickHandler {
void onClick(int position, String nameClicked);
}
/**
* Creates a SourceAdapter.
*
* #param clickHandler The on-click handler for this adapter. This single handler is called
* when an item is clicked.
*/
public KeyboardAdapter(List<String> myDataset, KeyboardAdapterOnClickHandler clickHandler) {
values = myDataset;
mClickHandler = clickHandler;
}
/**
* Cache of the children views for a forecast list item.
*/
public class KeyboardAdapterViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
// each data item is just a string in this case
private Button btnValue;
private String mName;
public View layout;
private int parentId;
private KeyboardAdapterViewHolder(View view) {
super(view);
//layout = view;
btnValue = view.findViewById(R.id.btn);
//parentId = ((View) btnValue.getParent()).getId();
// Call setOnClickListener on the view passed into the constructor (use 'this' as the OnClickListener)
view.setOnClickListener(this);
}
public void setData(String name) {
mName = name;
btnValue.setText(mName);
}
#Override
public void onClick(View view) {
int adapterPosition = getAdapterPosition();
mClickHandler.onClick(adapterPosition, mName);
}
}
#Override
public long getItemId(int position) {
return super.getItemId(position);
}
#Override
#NonNull
public KeyboardAdapterViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_layout, parent, false);
return new KeyboardAdapterViewHolder(v);
}
#Override
public void onBindViewHolder(#NonNull KeyboardAdapterViewHolder viewHolder, final int position) {
viewHolder.setData(values.get(position));
}
#Override
public int getItemCount() {
return values.size();
}
#Override
public int getItemViewType(int position) {
return 0;
}
public void remove(int position) {
values.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, values.size());
}
}
MainActivity:
protected void onCreate(Bundle savedInstanceState) {
...
String s = "test it";
mAdapter = new KeyboardAdapter(virtualKeyboardInit(s), MainActivity.this);
recyclerView1.setAdapter(mAdapter);
// empty list just to init rv
answerList = new ArrayList<>();
mAdapter1 = new KeyboardAdapter1(answerList, MainActivity.this); // doesn't work, error message "KeyboardAdapter1.KeyboardAdapterOnClickHandler cannot be applied to MainActivity"
recyclerView2.setAdapter(mAdapter1);
}
private List<String> virtualKeyboardInit(String s) {
boolean checkBool = true;
// convert string to array and then to list
String [] strArray = s.split("(?!^)");
stringList = new ArrayList<>(Arrays.asList(strArray));
// shuffle letters in the list
long seed = System.nanoTime();
Collections.shuffle(stringList, new Random(seed));
// API 24
// /String[] strArray = Stream.of(cArray).toArray(String[]::new);
return stringList;
}
#Override
public void onClick(int position, String nameClicked) {
mAdapter.remove(position);
}
These are just a fragment of code. So, what can I do in this case? Thank you for attention and help.
I am developing an android application where i am using a RecyclerView to display a list of items.I am getting the list from server as json.So my problem is within this list i am getting another list as item.That is if my main arraylist contain title and materials, the material is another arraylist.So can you please suggest a solution to display a list within recyclerview.
The code below is my adapter
public class CurriculumAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private Context mContext;
private ArrayList<Curriculum> mArrayListCurriculum;
public CurriculumAdapter(Context mContext, ArrayList<Curriculum> mArrayListCurriculum) {
this.mContext = mContext;
this.mArrayListCurriculum = mArrayListCurriculum;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.adapter_key_features, parent,false);
return new KeyFeatureViewHolder(v);
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (holder instanceof KeyFeatureViewHolder) {
((KeyFeatureViewHolder) holder).mTextViewFeatureTitle.setText(mArrayListCurriculum.get(position).getTitle());
}
}
#Override
public int getItemCount() {
return mArrayListCurriculum == null ? 0 : mArrayListCurriculum.size();
}
public static class KeyFeatureViewHolder extends RecyclerView.ViewHolder {
public TextView mTextViewFeatureTitle;
public KeyFeatureViewHolder(View itemView) {
super(itemView);
mTextViewFeatureTitle = (TextView) itemView.findViewById(R.id.txtFeature);
}
}
}
The code below is my fragment with dummy arraylist data
public class CourseCurriculumFragment extends Fragment {
private FragmentInterface mFragmentInterface;
private ArrayList<Curriculum> mArrayListCurriculum;
private ArrayList<Material> mArrayListMaterial;
private RecyclerView mRecyclerViewCurriculum;
private LinearLayoutManager mLinearLayoutManager;
private CurriculumAdapter mCurriculumAdapter;
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_course_curriculum, container, false);
return view;
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
initView(view);
}
private void initView(View view) {
mArrayListMaterial = new ArrayList<>();
mArrayListCurriculum = new ArrayList<>();
populateMaterials();
populateKeyFeatures();
mRecyclerViewCurriculum = (RecyclerView) view.findViewById(R.id.recyclerViewCurriculum);
mCurriculumAdapter = new CurriculumAdapter(getActivity(), mArrayListCurriculum);
mLinearLayoutManager = new LinearLayoutManager(getActivity());
mRecyclerViewCurriculum.setLayoutManager(mLinearLayoutManager);
mRecyclerViewCurriculum.setAdapter(mCurriculumAdapter);
mRecyclerViewCurriculum.setItemAnimator(new DefaultItemAnimator());
}
private void populateMaterials() {
mArrayListMaterial.add(new Material("12:00","pdf","","Sample Text","0"));
mArrayListMaterial.add(new Material("12:00","pdf","","Sample Text","0"));
}
private void populateKeyFeatures() {
mArrayListCurriculum.add(new Curriculum("UNIT 1",mArrayListMaterial));
mArrayListCurriculum.add(new Curriculum("UNIT 2",mArrayListMaterial));
mArrayListCurriculum.add(new Curriculum("UNIT 3",mArrayListMaterial));
}
}
A bind method in a holder is a good way to pass data to it.
In your case this bind method should take in a Curriculum and a Material object as parameters.
Inside the onBindViewHolder method of the adapter, instead of reaching into the variables of the holder, you should call this bind method.
In the implementation of the method inside the you KeyFeatureViewHolder class you should use these passed parameters and display them in the appropriate UI elements.
Lastly, to get the Material object data into adapter, add ArrayList<Material> as a constructor parameter just like you did with Curriculum.
Use RecyclerView with header, title as header and materials as items of that header. Look at this example.
You need to design a custom list for yourself. For example take an object like this.
public class ListItem {
public curriculumName = null;
public materialName = null;
}
Now populate this list after you parse the JSON string. Get your first Curriculum and populate the object like this
private ArrayList<ListItem> mListItemArray = new ArrayList<ListItem> ();
for(curriculum : mArrayListCurriculum) {
ListItem mListItemHead = new ListItem();
mListItemHead.curriculumName = curriculum.getName();
// Set the header here
mListItemArray.add(mListItemHead);
for(material : curriculum.getMaterials()){
ListItem mListItem = new ListItem();
mListItem.materialName = material.getName();
// Add materials here
mListItemArray.add(mListItem);
}
}
Now, you've a list with headers and materials. When the materialName in your mListItemArray is null, it identifies that this is a header and vice versa.
Now the trick is to modify your adapter of your RecyclerView so that you can bind proper view to your items in your list.
You can find an indication from this answer on how you can achieve this desired behaviour.
Basically, the idea is to modify your getItemViewType to pass the proper view in your onBindViewHolder. Your getItemViewType might look like this.
#Override
public int getItemViewType(int position) {
if (mListItemArray.get(position).curriculumName != null) {
// This is where we'll add header.
return HEADER_VIEW;
}
return super.getItemViewType(position);
}
Hi I got frustrated while searching solution for my problem.My problem is that i have a gridview to show all images which i selected from gallery.I want to display progressbar on each images in gridview.and while uploading images to server using multipart i want too update progressbar..
I displayed progressbar on each imageview but i am unable to show progress on each progressbar.
SO please help me to show how to show progress bar and their respective process on each imageview.
thanks in advance
Create a interface for an observer:
interface ProgressListener {
void onProgressUpdate(String imagePath, int progress);
}
Let the view holder implement that observer and know the image path:
public class ViewHolder implements ProgressListener {
ImageView imgQueue;
ProgressBar pb;
TextView tv;
String imagePath; //set this in getView!
void onProgressUpdate(String imagePath, int progress) {
if (!this.imagePath.equals(imagePath)) {
//was not for this view
return;
}
pb.post(new Runnable() {
pb.setProgress(progress);
});
}
//your other code
}
The adapter shall hold an map of observers for a particular image path/uri whatever and have an method that is called by the upload/download task. Also add methods to add and remove observer:
public class SelectedAdapter_Test extends BaseAdapter {
private Map<String, ProgressListener> mProgressListener = new HashMap<>();
//your other code
synchronized void addProgressObserver(String imagePath, ProgressListener listener) {
this.mListener.put(imagePath, listener);
}
synchronized void removeProgressObserver(String imagePath) {
this.mListener.remove(imagePath);
}
synchronized void updateProgress(String imagePath, int progress) {
ProgressListener l = this.mListener.get(imagePath);
if (l != null) {
l.onProgressUpdate(imagePath, progress);
}
}
//other code
}
In getView of the adapter register the view holder as an observer:
public View getView(final int i, View convertView, ViewGroup viewGroup) {
//other code
holder.imagePath = data.get(i).getSdcardPath();
this.addProgressObserver(holder.imagePath, holder);
return convertView;
}
The problem right now is, that we register the observer but don't unregister. So let the adapter implement the View.addOnAttachStateChangeListener:
public class SelectedAdapter_Test extends BaseAdapter implements View.addOnAttachStateChangeListener {
//other code
void onViewAttachedToWindow(View v) {
//We ignore this
}
void onViewDetachedFromWindow(View v) {
//View is not visible anymore unregister observer
ViewHolder holder = (ViewHolder) v.getTag();
this.removeProgressObserver(holder.imagePath);
}
//other code
}
Register that observer when you return the view.
public View getView(final int i, View convertView, ViewGroup viewGroup) {
//other code
convertView.addOnAttachStateChangeListener(this);
return convertView;
}
Finally you are able to tell the views what the progress is:
#Override
public void transferred(long num) {
int progress = (int) ((num / (float) totalSize) * 100);
selectedAdapter.onProgressUpdate(listOfPhotos.get(i).getSdcardPath(), progress);
}
One final problem remains, what if the activity is gone while the upload is in progress? You need to check if the activity is still alive. Maybe setting a flag in the adapter to true in onCreate and to false in onDestroy would do the trick. Then the last code fragment could check that flag and not notify the adapter on changes anymore.
So thats basically the idea of how to solve this. Does it work? I don't know I wrote it from scratch without any testing. And even if it does, you still have to manage the states when the progress is 0 or 100. But I leave that to you. Also you might want to change the BaseAdapter for an recyclerView so that we can get rid of the View.addOnAttachStateChangeListener.
add boolean in adapter class
public SelectedAdapter_Test(Context c, ArrayList<CustomGallery> data, boolean showProgress) {
mContext = c;
inflater = (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
this.data = data;
this.showProgress = showProgress;
}
changes in Adapter class getView
holder.pb = (ProgressBar) convertView.findViewById(R.id.progressbar);
if (showProgress)
holder.pb.setVisibility(View.VISIBLE);
else
holder.pb.setVisibility(View.GONE);
make changes in doFileUpload
private void doFileUpload(View v) {
View vi = v;
for (i = 0; i < listOfPhotos.size(); i++) {
<--your task-->
}
//**important**
SelectedAdapter_Test mTest = new SelectedAdapter_Test(context,data,false);
// set above adapter object respectively;
mList.setadapter(mTest);
}
FYI. pass showProgress value as true for the first time when you set adapter.