Develop Reference

ExpandableListView - show only children elements if each parent has only 1 child

I am using ExpandableListView to show parent-children relationship in Activity. That works fine but because in our case, parent and child information is similar, I would like to be able to hide parent information in cases where each parent has only 1 child.
For example, in screenshot below, my 3 product currently showing all have one child each. Because most of useful information is sufficient on parts (child) views, I would like to hide parents (product) view.
So, instead of showing it like this when each product has only 1 part:
, I would like to show it like this (without parent view):
Is that possible with ExpandableListView?

This is a hacky way but you can check if the children count is 1 and then inflate an empty view for the GroupView.
I'm using a viewHolder pattern but an example that works for me looks something like this.
#Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
ViewHolder viewHolder;
if(convertView == null){
viewHolder = new ViewHolder();
if(getChildrenCount(groupPosition) == 1) {
//INFLATE EMPTY VIEW
convertView = LayoutInflater.from(context).inflate(R.layout.empty_view, parent, false);
} else {
//THE ACTUAL VIEW
convertView = LayoutInflater.from(context).inflate(R.layout.actual_view, parent, false);
viewHolder.displayName = (TextView) convertView.findViewById(R.id.displayName);
}
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
if(getChildrenCount(groupPosition) != 1) {
viewHolder.name.setText("Name");
listView.expandGroup(groupPosition);
}
return convertView;
}
empty_view.xml looks like this
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="0dp"
android:layout_height="0dp">
</LinearLayout>

In my opinion using a recycler view will be easier for what you want to do. Here is a good example: https://www.bignerdranch.com/blog/expand-a-recyclerview-in-four-steps/

(Android GridView) CheckBox of the first item not work when I recycled convertView

I deleted almost all code in my project to find a hiding bug. There was a GridView that containing a frame layout, and the layout contained CheckBox. But I couldn't check the first check box.(others worked)
Finally (I think) I found an answer. But this is so weird. When I deleted lines for recycling convertView, the bug was gone. I changed from :
if(convertView == null) {
layout = (FrameLayout)View.inflate(maincon, R.layout.taste_brand, null);
} else {
layout = (FrameLayout) convertView;
}
to FrameLayout layout = (FrameLayout)View.inflate(maincon, R.layout.taste_brand, null);.
I really have no idea of this stuation. I attach rest codes.
TasteGridAdapter.java:
public class TasteGridAdapter extends BaseAdapter {
Context maincon;
public TasteGridAdapter(Context context) {
maincon = context;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
FrameLayout layout;
if(convertView == null) {
layout = (FrameLayout)View.inflate(maincon, R.layout.taste_brand, null);
} else {
layout = (FrameLayout) convertView;
}
layout.setLayoutParams(new GridView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.MATCH_PARENT));
return layout;
}
#Override
public int getCount() {
return 3;
}
#Override
public Object getItem(int position) {
return position;
}
#Override
public long getItemId(int position) {
return position;
}
}
onCreate of the activity :
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.taste);
TasteGridAdapter adapter = new TasteGridAdapter(this);
GridView grid = (GridView) findViewById(R.id.taste_grid);
grid.setAdapter(adapter);
}
taste.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<GridView
android:layout_weight="1"
android:id="#+id/taste_grid"
android:layout_width="match_parent"
android:layout_height="0dip"
android:columnWidth="87dip"
android:gravity="center"
android:horizontalSpacing="4dip"
android:numColumns="auto_fit"
android:padding="2dip"
android:stretchMode="columnWidth"
android:verticalSpacing="4dip" />
</LinearLayout>
taste_brand.xml:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="87dp"
android:layout_height="58dp">
<CheckBox
android:id="#+id/taste_brand_check"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</FrameLayout>

I encountered similar problem with first item in GridView. To resolve issue, remove 'new' keyword, and change existing views LayoutParams like that:
LayoutParams lp = layout.getLayoutParams();
lp.height = someHeight;
...do something with these LayoutParams. This hack resolves my issues. Conclusion, try to avoid creation of new LayoutParams object through "new".

layout.setLayoutParams(new GridView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.MATCH_PARENT));
put this line in this condition,
if(convertView == null) {
}
I was faced same problem, but i try this and its work for me. I hope it also work for you.

What you're experiencing has to do with the way Android recycles views in ListView, GridView, etc. You mention that your first checkbox is uncheckable, while your others remain working. I think you'll notice that the others only appear to work properly, since you haven't handled the recycling properly.
The reason your line
FrameLayout layout = (FrameLayout)View.inflate(maincon, R.layout.taste_brand, null);
seems to fix the problem is because this now inflates the views again each time they are used. I'll admit, when I started with this, re-inflating the views seemed to be the best solution; it entirely defeats the purpose of recycling, however, and you lose all the performance benefits otherwise gained.
So now to fix your problem:
First, I highly recommend using the ViewHolder pattern in conjunction with your BaseAdapter. More information on that can be found here.
Second, you should probably create a boolean array to match all the items in your GridView, and use it to determine whether or not an item should be clicked. Set the value of the corresponding boolean inside your checkbox listener and use that value inside getView(..) to check or uncheck that particular box.
An overall better solution might be to use an array (or list) of models inside your adapter class, each of these containing a boolean field accessible through isChecked and setChecked(boolean). Again, you would use this inside your getView(..) to display the views properly and change the value inside your checkbox OnCheckedChangeListener.
Hope that helps.

As jonstaff says, it's to do with View recycling.
If you're using a custom Adapter class for your GridView View binding, try modifying its getView() method to always instantiate a new View like:
public View getView(int position, View convertView, ViewGroup parent){
SomeView v = new SomeView(context); // <--- here
...
return v;
}
Instead of the typical:
public View getView(int position, View convertView, ViewGroup parent){
SomeView v;
if (convertView == null)
v = new SomeView (context);
else
v= (SomeView)convertView;
...
return v;
}
This may affect performance, but it solved my problem for a small GridView of Buttons.

Hide items in a listview

I have tried to hide items in a custom list adapter. I can hide the visibility of the text but I cannot hide the whole list item. It still shows the dividers etc. I have tried:
tv.setVisibility(View.INVISIBLE);
tv.setVisibility(View.GONE);
convertView.setVisibility(View.INVISIBLE);
convertView.setVisibility(View.GONE);
When I use the convertView i get a null pointer exception.

You can set ContentView with No Element.
In getView() of Your Custom Adapter.
if(condition)
{
convertView=layoutInflater.inflate(R.layout.row_null,null);
return convertView;
}
else
{
convertView=layoutInflater.inflate(R.layout.row_content,null);
return convertView;
}
your XML row_null.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</LinearLayout>

You have 3 ways to do this:
Remove the items from your list inside or outside the adapter.
Inside the adapter you can do it in the Constructor.
private List<String> list;
public MyAdapter(Context context, List<String> list) {
list.remove(0);
list.remove(1);
list.remove(<whateverPositionYouLike>);
this.list = list;
}
You need to figure out how many items you want to hide and need to build a similar logic.
#Override
public int getCount() {
// In this adapter, we are supposed to hide the first item of the list view
// Returning 0 if no of items are already 0
if(list.size() <=1)
return 0;
// if number of items are more than one, returning one item less
return list.size() - 1;
}
#Override
public Object getItem(int position) {
// skipping the position
return list.get(position + 1);
}
`
#Override
public View getView(final int position, View v, ViewGroup arg2) {
// this is important, as we are supposed to skip the first item of listview
final int localPosition = position +1;
ViewHolderItem holder;
if (v == null) {
holder = new ViewHolderItem();
v = inflater.inflate(R.layout.list_row, null);
v.setTag(holder);
} else {
holder = (ViewHolderItem) v.getTag();
}
return v;
}
`
Answer provided by #hims_3009

You cannot in the way you are trying to, you'll need to use a custom Adapter and implement in there the logic for showing/not showing a line.

If you want to hide a row in a listview, you need to delete data in that position. For example if you use array adapter and want to hide the row on 5. position. You have to delete line from your array and the call notifyDatasetChanged() method.
(You can delete data from array by using tempArray)
or use this way
private List<String> items = new ArrayList<String>();
// make list a new array, clearing out all old values in it.
for(i=0; i<10; i++)
{
if((i != 5) && (i != 6)){
// if k = 5 or 6, dont add those items to the list
items.add(something[i]); /// whatever your list items are.
}
}
ArrayAdapter<String> itemList = new
ArrayAdapter<String>(this,R.layout.itemlistlayout);
setListAdapter(itemlist);

If you want to hide an entire item you need to build some logic into your getView() method to make it skip over various parts of your data.
lets say you have an ArrayAdapter and I want to hide the data that is at index 2. Your getView() method could look something like this.
#Override
public View getView(int pos, View convertView, ViewGroup, parent){
View mView = convertView;
//TODO: Check if convertView was null, and inflate
// or instantiate if needed.
//Now we are going to set the data
mTxt = mView.findViewById(R.id.mTxt);
if(pos >= 2){
//If position is 2 or above, we ignore it and take the next item.
mTxt.setText(this.getItem(pos + 1).toString());
}else{
//If position is below 2 then we take the current item.
mTxt.setText(this.getItem(pos).toString());
}
return mView;
}
Note that this example is generalized, it is not meant to be able to be dropped directly into your project. I had to make assumptions about some things which I don't know the truth on. You can use the same concept as I've shown here though and modify it to your situation to be able to "hide" rows in your ListView.

If you already have a custom list adapter you can just call notifyDataSetChanged() on the adapter and the adapter itself has of course to implement the logic to filter out the views for the rows you want to hide. These are the methods that come to my mind that need to reflect that logic:
#Override
public Object getItem(int position) {
return mItems.get(position);
}
#Override
public int getCount() {
return mItems.size();
}
#Override
public View getView(final int position, final View convertView, final ViewGroup parent) {
// here goes your logic to hide a row
Additionally you might have to change getItemId() as well.

I think I have a much easier / safer solution: you just have to "embed" your item in a Layout, and change the visibility of this parent 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="wrap_content"
android:orientation="horizontal" >
<!-- Embed ListView Item into a "parent" Layout -->
<LinearLayout
android:id="#+id/parentLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<!-- This is the normal content of your ListView Item -->
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="World" />
</LinearLayout>
</LinearLayout>
Then in your code just do:
public View getView(int position, View view, ViewGroup parent) {
if (view == null) {
LayoutInflater li = mActivity.getLayoutInflater();
view = li.inflate(R.layout.my_listview_item, null);
}
LinearLayout parentLayout = (LinearLayout) view.findViewById(R.id.parentLayout);
if (shouldDisplayItem(position)) {
parentLayout.setVisibility(View.VISIBLE);
} else {
parentLayout.setVisibility(View.GONE);
}
return view;
}
This way you always use/reuse the same item, and just hide/show it.

Cannot change the visiblity of an ImageView

I have a ListView using a custom cursoradapter to fill the ListView.
The row.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<LinearLayout
android:orientation="vertical"
android:layout_width="0dip"
android:layout_weight="1"
android:layout_height="fill_parent">
<TextView
android:id="#+id/title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:singleLine="true"
android:gravity="center_vertical"
android:ellipsize="marquee"
android:textSize="24dp" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/artist"
android:singleLine="true"
android:ellipsize="marquee"
android:textSize="14dp" />
</LinearLayout>
<ImageView
android:id="#+id/currentplaying"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_marginLeft="1dip"
android:src="#android:drawable/ic_media_play"
android:contentDescription="#string/now_playing"
android:visibility="gone" />
</LinearLayout>
As you can see, the ImageView's visibility is gone. I want to make it
visible for one particular row. Here is the code I tried but it is not
working...
View view = getListView().getAdapter().getView(0, null, null);
ImageView iv = (ImageView)view.findViewById(R.id.currentplaying);
iv.setVisibility(ImageView.VISIBLE);
Thanks in advance.
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if(convertView==null) {
holder = new ViewHolder();
convertView = inflater.inflate(R.layout.yourlayout, null);
holder.imgViewLogo = (ImageView) convertView.findViewById(R.id.imgViewLogo);
convertView.setTag(holder);
}
else {
holder=(ViewHolder)convertView.getTag();
}
if(position==0) {
holder.imgViewLogo.setVisiblity(View.VISIBLE);
}
return convertView;
}
EDIT:
I got it working. I used this to start the ListView activity.
intent.putExtra("id", c.getInt(c.getColumnIndex(DatabaseHelper._ID)));
startActivity(intent);
In the ListView activity,
currentplayingid = getIntent().getExtras().getInt("id");
Then I added this in bindview()
ImageView imgview = (ImageView)view.findViewById(R.id.currentplaying);
int id = c.getInt(c.getColumnIndex(DatabaseHelper._ID));
if (id == SongsListActivity.this.currentplayingid)
imgview.setVisibility(View.VISIBLE);
else
imgview.setVisibility(View.GONE);

I got it working. I used this to start the list view activity.
intent.putExtra("id", c.getInt(c.getColumnIndex(DatabaseHelper._ID)));
startActivity(intent);
In the listview activity,
currentplayingid = getIntent().getExtras().getInt("id");
Then i added this in bindview()
ImageView imgview = (ImageView)view.findViewById(R.id.currentplaying);
int id = c.getInt(c.getColumnIndex(DatabaseHelper._ID));
if ( id == SongsListActivity.this.currentplayingid )
imgview.setVisibility(View.VISIBLE);
else
imgview.setVisibility(View.GONE);

perhaps you should do it in getView() of your adapter
EDIT:
#Override
public View getView(int position, View convertView, ViewGroup parent)
{
// codes...
if (position == 0)
{
holder.imgViewLogo.setVisibility(ImageView.VISIBLE);
}
else
{
holder.imgViewLogo.setVisibility(ImageView.GONE);
}
// codes...
}

You have to do it like this
iv.setVisibility(View.VISIBLE);

If it is working some time then may be i can help you. What happen that whenever you move you listview it recreates all views again in this case it never save the last state of view. So what you need to do is to save state of your each imageview and in getView() you have to set accordingly.I am posting one of my answer it may help you.
Here is a little code for your help: I will create a boolean arraylist.
private ArrayList imageview_visible = null;
Then I will set states of all imageview as false in my constructor:
for (int i=0; i < no_of_elements.size(); i++) {
imageview_visible.add(i, false);
}
In your getView write this code:
public View getView (int position, View convertView, ViewGroup parent)
{
//WRITE YOUR CODE
if (imageview_visible.get(position) == true)
{
//SET YOUR IMAGE VIEW AS VISIBLE
} else {
// SET IMAGEVIEW AS GONE
}
}
Whenever you unhide or hide your view just save it into imageview_visible.set(true or false) this will save state of you all imageview and set every image view accordingly

Use LayoutInflater to get view object
LayoutInflater inflater = this.getLayoutInflater();
View rowView = inflater.inflate(R.layout.row, null, true);
ImageView iv = (ImageView)view.findViewById(R.id.currentplaying);
iv.setVisibility(ImageView.VISIBLE);

Try the following code as follows,
private class ViewHolder
{
ImageView imgViewLogo;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder holder;
if(convertView==null)
{
holder = new ViewHolder();
convertView = inflater.inflate(R.layout.yourlayout, null);
holder.imgViewLogo = (ImageView) convertView.findViewById(R.id.imgViewLogo);
convertView.setTag(holder);
}
else
{
holder=(ViewHolder)convertView.getTag();
}
if(position==0)
{
holder.imgViewLogo.setVisiblity(View.VISIBLE);
}
return convertView;
}
It Works for me...It may help you.

I ran into similar problems where several widgets would appear for some rows but not for others. The problems were due to view recycling. I'm not exactly sure if that's your issue here, but you should handle it anyway. The trick is to set visibility for every row; instead of just for the row that you want to appear/disappear.
So:
if (position == 0)
{
iv.setVisibility(ImageView.VISIBLE);
}
else
{
iv.setVisibility(ImageView.GONE);
}
Otherwise, you're assuming that for positions other than 0 the visibility is GONE but that might not be the case with view recycling. I do this work in bindView, by the way. Not sure if that's technically correct.

I have the same issue... i solved with a non standar solution, but worked for me...
v.setImageResource(R.color.transparent);
importing R from android
import android.R;

Both iv.setVisibility(View.VISIBLE); and iv.setVisibility(ImageView.VISIBLE); are correcte but It's better to use View instead of ImageView because VISIBLE & GONE are defined in View class.
You most change Both Visibility (VISIBLE or GONE) in that if. like:
if(?)
iv.setVisibility(View.VISIBLE);
else iv.setVisibility(View.GONE);

You can hide or show views using setVisibility(int) .
use iv.setVisibility(View.VISIBLE);

OnItemClickListener Not Triggered on Android GridView

I have a Gridview filled by an Adapter which returns LinearLayouts each contains an ImageButton and TextView.
In the adapter I am binding an onClick and onLongClick event to the ImageButton.
I am trying to bind OnItemClickListener to the gridview but I don't know why that the onItemclicked never fired up.
It's my 6th hour without anything.
By the way;
OnItemSelectListener working perfectly on the Grid.
I am checking if some piece of code accidentally handles the onItemClicked but couldn't catch yet.
I need help guys.
gridView = (GridView) layoutInflater.inflate(R.layout.gridview, null);
gridView.setOnItemClickListener(new ItemClickListener());
.
.
.
//inner handler class
class ItemClickListener implements AdapterView.OnItemClickListener {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Toast.makeText(mainActivity.getApplicationContext(),view + " clicked at pos " +
i,Toast.LENGTH_SHORT).show();
}
}

Do not use clickable objects in the grid. In that case Android cannot handle the click event of GridView.
Instead, use something to show a similar user interface view. Then handle that object's click actions.
Don't: put Button in the GridView to perform some click actions.
Do: put an ImageView instead of ImageButton and handle ImageView's click events.

If you wants to use Button or ImageButton then you need to write these attributes in your xml code of the widgets.
android:focusable="false"
android:focusableInTouchMode="false"
Its works for me.
But in GridView, Try to avoid use of these widgets. You can use any other widgets in place of these (Like ImageView or any other).

Also make sure, that your ListAdpter returns true for
public boolean isEnabled(int _position)
for the position you want to click.

Hey guyz finally got a solution...
what we were doing is directly accessing the Layout inside the GridView, so the onItemClickListener finds it confusing to access the item.
So the solution is to apply the onClickListener inside the Adapter (i.e. normally ArrayAdapter)
so what i m trying to say is:
public View getView(int position, View convertView, ViewGroup parent) {
//Here row is a view and we can set OnClickListener on this
final View row;
ViewHolder holder = null;
if (convertView == null) {
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
//Here we inflate the layout to view (linear in my case)
row = inflater.inflate(layoutResourceId, parent, false);
holder = new ViewHolder();
holder.imageTitle = (TextView) row.findViewById(R.id.text);
holder.image = (ImageView) row.findViewById(R.id.image);
row.setTag(holder);
} else {
row = convertView;
holder = (ViewHolder) row.getTag();
}
ImageItem item = data.get(position);
holder.imageTitle.setText(item.getTitle());
holder.image.setImageBitmap(item.getImage());
//Now get the id or whatever needed
row.setId(position);
// Now set the onClickListener
row.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(context, "Clicked" + row.getId() + "!!",
Toast.LENGTH_SHORT).show();
}
});
return row;
}

Try to set
android:clickable="false"
android:focusable="false"

I meet same problem too, because of several reasons.
So, here's my tips:
Extend BaseAdapter for your adapter;
Use OnClickListener inside the getView in adapter instead setting OnItemClickListener for GridView;
Avoid setting LayoutParams multiple times;
Check if position = 0, don't use convertView, inflate new View;
Set OnClickListener not only for parent View, but for any child View, if any;
Make all your Views clickable.
I just tested it on 4 devices, and this solution works as expected. Hope, it will help in your case.
Correct me, if I made something wrong.
Layout code XML:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="100dp"
android:layout_height="100dp"
android:background="#273238"
android:clickable="true"
android:focusable="true"
android:focusableInTouchMode="true"
android:padding="1dp">
<ImageView
android:id="#+id/open_image_item_imageview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/loh"
android:clickable="true"
android:focusable="false"
android:focusableInTouchMode="false"
android:scaleType="centerCrop"/>
<TextView
android:id="#+id/open_image_item_textview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:focusable="false"
android:focusableInTouchMode="false"
android:layout_gravity="bottom"
android:padding="4dp"
android:textSize="10sp"
android:ellipsize="start"
android:background="#55000000"
android:textColor="#FFFFFF"
android:text="image name"/>
</FrameLayout>
Adapter code Java:
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = null;
if(convertView != null && position != 0)
view = convertView;
else{
view = LayoutInflater.from(getContext()).inflate(R.layout.open_image_item_layout, null, false);
view.setLayoutParams(new GridView.LayoutParams(GridView.AUTO_FIT, size));
}
TextView textView = (TextView)view.findViewById(R.id.open_image_item_textview);
ImageView imageView = (ImageView)view.findViewById(R.id.open_image_item_imageview);
...
View.OnClickListener onClickListener = getOnClickListener(files[position]);
view.setOnClickListener(onClickListener);
textView.setOnClickListener(onClickListener);
imageView.setOnClickListener(onClickListener);
return view;
}