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How to handle dynamically created buttons in android?

I am new to android development, in fact its my first application. I have created a dynamic layout in my project based on Json. Each object includes an "id" key and some more string keys. every object in my json should be transformed to a cardview inside a recylcerview and each cardview has a button.
My problem is handling these dynamic buttons. Is it possible to determine which button was clicked?

View.id is an integer, and you shouldn't set arbitrary values to it if the View is generated dinamically, what you can use though is View.tag. So you can assign the id defined in the JSON to tag and then check the tag value when the View is clicked. E.g.
val view1 = View(context)
view1.tag = "id from JSON 1"
view1.setOnClickListener(this::onViewClicked)
val view2 = View(context)
view2.tag = "id from JSON 2"
view2.setOnClickListener(this::onViewClicked)
// ...
private fun onViewClicked(view: View){
val jsonId = view.tag as? String
// ...
}
If your min sdk level at least 17, another option would be to generate ids dinamically with View.generateViewId() and store them in a Map together with your JSON ids

Use a Tag to differentiate the buttons. Add OnClickListener to all Button and set different String tag to button.
button.setOnClickListener(this);
Add ClickListener
#Override
public void onClick(View view){
String tag = (String)view.getTag();
if(tag.equals(tag1)){
// action here
}
//.......
.....
}

Yeah pretty straight, all you have to do is to give them a unique id
I assume you must have a JSON array for dynamic buttons creation.
sample code
public Button createButton(Context context,String text,int buttonNo){
//here set the properties
Button bt = new Button(context);
bt.setText(text);
bt.setId(buttonNo);
bt.setTag(buttonNo);
bt.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View view){
//handle the button click, unique id , you can use to differentiate
int id = view.getId();
}
});
return bt;
}
call this above method in for loop or as many times you want to create.
you can also set a tag as mentioned above to store more information.

Finally I put the OnClickListener in onBindViewHolder event inside my customAdapter class as below:
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> implements View.OnClickListener {
private Context context;
private List<MyData> my_data;
public CustomAdapter(Context context, List<MyData> my_data) {
this.context = context;
this.my_data = my_data;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.card,parent,false);
return new ViewHolder(itemView);
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.match_date.setText(my_data.get(position).getMatch_date());
holder.home_name.setText(my_data.get(position).getHome_name());
holder.away_name.setText(my_data.get(position).getAway_name());
holder.button.setId(my_data.get(position).getId());
holder.button.setTag(my_data.get(position).getStringId());
holder.button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
int intHomeGoals = Integer.parseInt(holder.edtHomeGoals.getText().toString());
int intAwayGoals = Integer.parseInt(holder.edtAwayGoals.getText().toString());
if (intHomeGoals == intAwayGoals)
{
Toast.makeText(context, "00000", Toast.LENGTH_SHORT).show();
}
}
});
Glide.with(context).load(my_data.get(position).getHome_logo()).into(holder.home_logo);
Glide.with(context).load(my_data.get(position).getAway_logo()).into(holder.away_logo);
}

EditText constantly returns Empty - Android

I'm attempting to null check an EditText (which should be simple enough) however each time I enter text into my two ET's - they always return as empty: "" and they should not (if they have text in them).
I've looked over several other SO articles related to this and none of the fixes seem to resolve the issue.
Can anyone spot what I might be doing wrong in this instance?
Source Snippet:
Java class:
...
public void doneClicked(View v) throws JSONException {
LayoutInflater li = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v1 = li.inflate(R.layout.profile_notification_settings_list_edit, null);
final EditText label = (EditText) v1.findViewById(R.id.emaillabel);
final EditText value = (EditText) v1.findViewById(R.id.emailvalue);
String sValue = value.getText().toString();
if (sValue.matches("")) {
Toast.makeText(this, "You did not enter a value", Toast.LENGTH_SHORT).show();
return;
}
String sLabel = label.getText().toString();
if (sLabel.matches("")) {
Toast.makeText(this, "You did not enter a label", Toast.LENGTH_SHORT).show();
return;
}
...
Adapter:
#Override
public View getView(final int i, View view, ViewGroup viewGroup) {
view = inflater.inflate(R.layout.profile_notification_settings_list_edit, null);
EditText value = (EditText) view.findViewById(R.id.emailvalue);
value.setHint("Value");
value.setText(valueList[i]);
EditText label = (EditText) view.findViewById(R.id.emaillabel);
if (labelList != null)
label.setHint("Label");
label.setText(labelList[i]);
Full source:
Java Class:
https://pastebin.com/y1e9J1yE
Adapter:
https://pastebin.com/Zqh3eCAk

Because everytime you click you are creating a new view which has nothing to do with the views currently being displayed on the screen
public void doneClicked(View v) throws JSONException {
// don't inflate new views
LayoutInflater li = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v1 = li.inflate(R.layout.profile_notification_settings_list_edit, null);
final EditText label = (EditText) v1.findViewById(R.id.emaillabel);
final EditText value = (EditText) v1.findViewById(R.id.emailvalue);
// ... code
Note : you cannot directly fetch the data from rowItemVies from ListView , so you need to add method in your adapter class to get the selected position through which you can fetch the rowView using yourListView.getChildAt(position) and further fetch data from children in rowView

use
sValue.trim().equals("") instead of sValue.matches("")

Calling new activity from an item inside a recyclerview row

I need to call a new activity, when a button inside one of my recyclerview row elements is called. Each row item in the list contains 4 buttons, one of which needs to open a new activity which will be used to edit the data in that row.
Here is the code for my button so far:
public void onBindViewHolder(CounterLayoutAdapter.ViewHolder holder, final
int position) {
final Counter counter = counterList.get(position);
//counter is a class which holds the data that will be displayed on one
//row
String comment = counter.getComment();
String name = counter.getCounterName();
int number = counter.getCurrentValue();
//LocalDate modifyDate = counter.getLastModifyDate();
Button up = holder.itemView.findViewById(R.id.buttonUp);
Button down = holder.itemView.findViewById(R.id.buttonDown);
Button reset = holder.itemView.findViewById(R.id.buttonReset);
Button edit = holder.itemView.findViewById(R.id.buttonEdit);
Button delete = holder.itemView.findViewById(R.id.buttonDelete);
// code for 4 other buttons goes here
//
edit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
}
});
Since I need the activity that I open to return user inputted data for me, I am using startActivityForResult. However, as far as I can tell, this will only work inside an actual activity class.
So then I tried passing the mainactivity context to my CounterLayoutAdapter class, where all of my button code is. However, the OnBindViewHolder method still cannot access it there. So I tried to pass the context to OnBindViewHolder, but that doesn't work either, as it won't override the abstract class if i do that..
So, how on earth can I call a new activity here?
Alternatively, if there is some other way to get user input into 4 fields and return that input back to the adapter, without calling an activity, that would work as well.
EDIT: viewholder and layout inflation
public static class ViewHolder extends RecyclerView.ViewHolder implements
View.OnClickListener {
private TextView name;
private TextView comment;
private TextView number;
//private TextView date;
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
comment = itemView.findViewById(R.id.textComment);
name = itemView.findViewById(R.id.textName);
number = itemView.findViewById(R.id.editTextNum);
//date = itemView.findViewById(R.id.textDate);
}
#Override
public void onClick(View view) {}
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View inflatedView =
LayoutInflater.from(parent.getContext()).inflate(R.layout
.row_layout, parent, false);
return new ViewHolder(inflatedView);
}

You can call startActivityForResult() in adapter class.
Get context in adapter like Context context=holder.up.getContext();
then in your button's OnClickListener do this.
edit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent=new Intent(context,ActivityYouWantToStart.class);
//Pass any extras if you want to.
((Activity)context).startActivityForResult(intent,REQUEST_CODE);
}
});
Then in your activity (which contain this recyclerView) override onActivityResult like this
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CODE) {//same REQUEST_CODE you used in adapter
if (resultCode == RESULT_OK) {
//Do your thing and get the data you want.
adapter.onDataReady(Data data);//where adapter is your recycler adapter,
//and data is whatever data you want to pass to adapter
//(Data you got from the activityResult, do not confuse it with onActivityResult's parameter 'Intent data')
}
}
}
Finally in your Recycler Adapter class, define onDataReady() function like
public void onDataReady(Data data){
//Update RecyclerView with new data
}
Hope this helps. I once did this, and it works for me. Let me know if you have any problem.

As you see , you do not have to findViewById in onBindViewHolder.
public void onBindViewHolder(CounterLayoutAdapter.ViewHolder holder, final
int position) {
final Counter counter = counterList.get(position);
//counter is a class which holds the data that will be displayed on one
//row
String comment = counter.getComment();
String name = counter.getCounterName();
int number = counter.getCurrentValue();
//LocalDate modifyDate = counter.getLastModifyDate();
holder.edit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
}
});
Then you should init edit in ViewHolder constructor.
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
comment = itemView.findViewById(R.id.textComment);
name = itemView.findViewById(R.id.textName);
number = itemView.findViewById(R.id.editTextNum);
//date = itemView.findViewById(R.id.textDate);
// init four button
edit = itemView.findViewById(R.id.buttonEdit)
}

how to get textview text

In my android app, I have a activity that contain a listview. And within the each row of the listview, i have another listview let called it lv. Inside this lv, it contain some textview. My question is how can i get the text from the listview (A)?
I know that if there is only one listview and in order to get the text of each row when i click on a button, i can use the following code
textview.getText().toString();
However, when i try with this code to get the text in lv, it always give me the last value (n row) in lv. I am not able to get the text of 1st row to n-1 row of lv.
UPDATE:
The follow are the code where i want to get the text, the ordered[] is passed from a custom adapter to another custom adapter (which is the following code)
public View getView(int position,View view,ViewGroup parent) {
LayoutInflater inflater=((Activity) context).getLayoutInflater();
View rowView=inflater.inflate(layoutResourceId, null,true);
txt1 = (TextView)rowView.findViewById(R.id.textView1);
txt2 = (TextView)rowView.findViewById(R.id.textView2);
txt3 = (TextView)rowView.findViewById(R.id.textView3);
txt4 = (TextView)rowView.findViewById(R.id.textView4);
txt5 = (TextView)rowView.findViewById(R.id.textView5);
txt6 = (TextView)rowView.findViewById(R.id.textView6);
txtoid = (TextView)rowView.findViewById(R.id.textView7);
final Button btnGet = (Button)rowView.findViewById(R.id.btnGet);
tmp = position;
String tmp2 = String.valueOf(ordered[position]);
txtoid.setText(tmp2);
btnGet.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(btnconfirm.getText().toString().equals("Get")){
String tmp1 = txtq.getText().toString();
System.out.println("tmp1: "+tmp1);
}
}
});
....
Anyone help will be nice!
Thanks

rowView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View rootView) {
// TODO Auto-generated method stub
TextView myText = (TextView)rootView.findViewById(R.id.textView7);
Log.d("","myText:" + myText.getText()); //you can get each row values.
}
});

Add the values on ArrayList in Android [closed]

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I have develop one application. Here i have to add the value on ArrayList. if i have to click Button means that value have to add on that ArrayList. I have to click another Button means that added list is displaying. How can i do? Please give me solution.
These are my values:
product_id = getIntent().getStringExtra("id");
product_title = getIntent().getStringExtra("title");
product_image = getIntent().getStringExtra("image");
product_price = getIntent().getStringExtra("price");
product_desc = getIntent().getStringExtra("description");
arrayList = new ArrayList<String>();
arrayList.add(product_title);
arrayList.add(product_price);
arrayList.add(product_id);
arrayList.add(product_image);
arrayList.add(product_desc);
I have to add these values on ArrayList while clicking the Button:
valueaddlist = (Button) findViewById(R.id.valueaddlist);
valueaddlist.setOnClickListener(new OnClickListener() {
public void onClick(View v){
Intent intent = new Intent(this,AddedListProducts.class);
intent.putExtra("WishListProducts", arrayList);
startActivity(intent);
}
In the AddedListProducts have to displaying all added products list.
How can i do ?
please give me solution for these ?
EDIT:
This is my AddedListProducts class code:
wishlist_products = (ListView) findViewById(R.id.wishlist_products);
if(getIntent().getExtras() !=null){
WishListProducts = (ArrayList<String>) getIntent().getExtras().getSerializable("WishListProducts");
System.out.println(WishListProducts);
wishlistproductsAdapter = new WishListAdapter(this,WishListProducts);
wishlist_products.setAdapter(wishlistproductsAdapter);
}
In these arraylist am getting values.how can i set the value on adapter file and UI.
This is my adapter file code:
public class WishListAdapter extends BaseAdapter{
WishListAdapter mListViewAdapter;
private Activity mActivity;
private ArrayList<String> mwishlistProducts;
public ImageLoader mImageLoader;
private static LayoutInflater inflater=null;
public WishListAdapter(Activity activity, ArrayList<String> products) {
mActivity = activity;
this.mwishlistProducts=products;
inflater = (LayoutInflater)mActivity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
class ViewHolder{
private ImageView productImageView;
private TextView productTitleView;
private TextView productPriceView;
private TextView productDescView;
public ViewHolder(ImageView productImageView, TextView productTitleView,TextView productPriceView,TextView productDescView) {
super();
this.productImageView = productImageView;
this.productTitleView = productTitleView;
this.productPriceView = productPriceView;
this.productDescView = productDescView;
}
} // ViewHolder-class
public int getCount() {
return mwishlistProducts.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
ViewHolder holder;
final String wishlistproductList = mwishlistProducts.get(position);
if( convertView == null )
{
convertView = inflater.inflate(R.layout.list_product, null);
ImageView productImage=(ImageView)convertView.findViewById(R.id.productimage);
TextView productTitle = (TextView)convertView.findViewById(R.id.producttitle);
TextView productPrice = (TextView)convertView.findViewById(R.id.productprice);
TextView productDesc = (TextView)convertView.findViewById(R.id.productdescription);
holder = new ViewHolder(productImage,productTitle,productPrice,productDesc);
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
convertView.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
holder.productTitleView.setText();
holder.productPriceView.setText();
holder.productDescView.setText();
mImageLoader=new ImageLoader();
mImageLoader.DisplayImage();
return convertView;
}
}
In these holder file what i have to set ????
How can i set that arraylist value here.please help me yaar..
EDIT:
More products is displaying on one listview.
Now i have to click one list item means its go to detail description page.here i have to click button means that product detail value is adding and have to display on AddedListProducts Page.
now i ll go to back and click another product means click button means that product detail also added and have to display on AddedListProducts page with that old added products...
i have to add products from that listview and go to next page and clicking button means have to display that all added products on AddedListProducts page.how can i do ???
Above code ly displaying last added product ly.I want to display all added products on that list.

After getting value from intent:
ArrayList<String> arrayList = new ArrayList<String>();
valueaddlist = (Button) findViewById(R.id.valueaddlist);
valueaddlist.setOnClickListener(new OnClickListener() {
public void onClick(View v){
arrayList.add(product_id);
arrayList.add(product_title);
arrayList.add(product_image);
arrayList.add(product_price);
arrayList.add(product_desc);
}
valuedisplaylist = (Button) findViewById(R.id.valuedisplaylist);
valuedisplaylist.setOnClickListener(new OnClickListener() {
public void onClick(View v){
Intent intent = new Intent(this,AddedListProducts.class);
intent.putStringArrayListExtra("arrayList", (ArrayList<String>) arrayList);
startActivity(intent);
}
May be this will help you.
In your second activity get the arraylist like :
ArrayList<String> ar1=getIntent().getExtras().getStringArrayList("arrayList"); ArrayAdapter<String> arrayAdapter =
new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, ar1);
lv.setAdapter(arrayAdapter);
Then have a look at this question to display arraylist: Populating a ListView using an ArrayList?

ArrayList<Integer> arrayList = new ArrayList<>();
arrayList.add(5);