I have a list view which contains a button in each row of the list.
Based upon a field, I want to make this button invisible.
My getView method inside adapter is shown below.
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
Activity activity = (Activity) getContext();
View view = convertView;
if (convertView == null) {
LayoutInflater inflater = activity.getLayoutInflater();
view = inflater.inflate(R.layout.listrow, null);
}
final Details details = getItem(position);
Button btn = (Button) view.findViewById(R.id.btn);
if(details.check()) {
btn.setVisibility(View.INVISIBLE);
}
}
When I load this page the data comes correctly. But when simply scroll through this list, then this button is getting invisible. Whats the reason for this? When I remove that if section, then i will get buttons for all rows, even if i scrolls. Is there any problem giving invisible inside getView(). Please reply. Thanks in advance.
Add the following:
if(details.check()) {
btn.setVisibility(View.INVISIBLE);
}
else {
btn.setVisibility(View.VISIBLE);
}
and...it had better use
LayoutInflater.from(getContext())
instead of activity.getLayoutInflater()
set the clickable property of listview false in xml or like:
getListView().setClickable(false);
Related
What do I want to achieve?
In the below SS, when user touches 'vote' button, these vertical progress bars (custom) will be set according to the voting percentages retrieved from server for that particular row.
What is the obstacle?
I have onClickListener inside getView of the CustomAdapter, and when I manipulate the ProgressBar instance (which is in ViewHolder Class), supposingly I want to see the updated ProgressBar on ONLY the one row of the listview that has triggered that action, but, I see every once 3 rows that I scroll down.
Example: I clicked first row, so first row has updated its progress bar, but 4th, 7th, 10th... rows are also updated EVEN IF I don't touch 'vote button'.
My Guessing
I think this problem is related to recycling the view, the weird number is 3 in this case but when I make rows smaller it goes '4', so that is the only clue I have.
SS & Codes
ScreenShot: bit.ly/sofscreenshot
Code:
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
convertView = mInflater.inflate(layout, null);
holder = new ViewHolder();
//some more initialization
holder.pb1 = (ProgressBar) convertView.findViewById(R.id.leftProgress);
holder.pb2 = (ProgressBar) convertView.findViewById(R.id.rightProgress);
holder.leftVoteButton = (Button) convertView.findViewById(R.id.leftButton);
holder.rightVoteButton = (Button) convertView.findViewById(R.id.rightButton);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.leftVoteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
holder.pb1.setVisibility(View.VISIBLE);
holder.pb2.setVisibility(View.VISIBLE);
/Some codes...
holder.pb1.setProgress(50);
holder.pb2.setProgress(50);
}
});
}
private class ViewHolder {
//some more objects
ProgressBar pb1;
ProgressBar pb2;
Button leftVoteButton;
Button rightVoteButton;
}
All the answers and comments are appreciated, have a great day and thank you.
You're doing it wrong.
The problem is that you need to have a Model somewhere, and change its status. Then the view is updated regarding the model status.
For example, let's say that this is a "StackOverflow" app, and you have a list of answers. The user upvote the second answer. This means that the second element of the List is upvoted.
Now what?
When the adapter is going through your list of object it will "fire" the getView method for that position. Then you have to update that position according to your model. So, if the position is 1, the adapter is trying to show the second Answer, and you have to set the button to "upvoted". Otherwise you have to set it as "normal".
private List<Answer> answers;
public View getView(int position, View convertView, ViewGroup parent) {
// here get your view (or initialize it)
// get the matching answer
Answer answer = answers.get(position);
if(answer.isUpvoted()) {
holder.pb1.setVisibility(View.VISIBLE);
holder.pb2.setVisibility(View.VISIBLE);
} else {
holder.pb1.setVisibility(View.INVISIBLE);
holder.pb2.setVisibility(View.INVISIBLE);
}
holder.leftVoteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
holder.pb1.setVisibility(View.VISIBLE);
holder.pb2.setVisibility(View.VISIBLE);
// not sure on how to get this answer here
// you probably have to go "upper" and manage the click from the ListView
answer.setUpvoted(true);
}
});
}
Im trying to implement instagram like listview , in each row there is like button and also comment box. the question is how can i achieve similar function in listview which means each row is specific and its not repeating for other rows , what i tries is , when a user clicks on button after some item , all other items are clicked! means the clicked item is repeating and its obvious i don't want this! how can i achieve instagram like row
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
viewHolder mHolder;
if(convertView==null){
mHolder = new viewHolder();
convertView = mInflator.inflate(R.layout.row_all_artist, parent, false);
mHolder.mArtistName = (TextView) convertView.findViewById(R.id.artist_name);
mHolder.mFollowers = (TextView) convertView.findViewById(R.id.artist_followers);
mHolder.mFollow = (Button) convertView.findViewById(R.id.artist_follow);
AppLogic.ChangeTextViewFont(mContext, mHolder.mArtistName);
convertView.setTag(mHolder);
} else{
mHolder = (viewHolder) convertView.getTag();
}
mHolder.mArtistName.setText(mItems.get(position).getArtistFullName());
mHolder.mFollowers.setText(mItems.get(position).getArtistFollowers());
mHolder.mFollow.setTag(R.id.artist_follow,mItems.get(position).getArtistID());
mHolder.mFollow.setOnClickListener((OnClickListener) mContext);
return convertView;
}
EDIT
my question is not about touching items or setting unlike listener or like this! the problem is when i click the button i change its background color , but this color is repeating on every 10 item on the list! there is a related question to me here : ListView repeated CheckBox behavior every 10th item erratically
public void onClick(final View v) {
if (!AppLogic.isLoggined(mShared)) {
AppLogic.ToastMaker(getApplicationContext(),
getResources().getString(R.string.msg_loginError));
startActivity(new Intent(FirstTimePage.this, Register.class)
.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP));
} else {
AppLogic.doFollow(FirstTimePage.this, v, mShared);
}
}
Prevent getting focus by the button.
Add this to the top element in your row_all_artist.xml custom view
android:descendantFocusability="blocksDescendants"
Create a new OnClickListener for every row, or check the View given in the argument at your current listener.
You are setting your mContext as the OnClickListener
mHolder.mFollow.setOnClickListener((OnClickListener) mContext);
You should just implement the ListView method setOnItemClickListener and then check for the position of the item that was clicked. Tags are also very helpful here.
Example: Adding an onclicklistener to listview (android)
I have a list with each row having a radio button. I'm using the folowing code to toggle between them(TEMP is a static variable used to keep track of the element which has been selected, so that when listview refreshes the view I'm able to select it again) :
public void onClickRadioButton(View view) {
final int position = listView.getPositionForView(view);
View rowElement = ((View) view.getParent());
// uncheck previous checked button.
if (listRadioButton != null)
listRadioButton.setChecked(false);
// assign to the variable the new one
listRadioButton = (RadioButton) view;
// find if the new one is checked or not, and set "listIndex"
if (listRadioButton.isChecked()) {
listIndex = ((ListView) rowElement.getParent())
.getPositionForView(rowElement);
TEMP = listIndex;
} else {
listRadioButton = null;
listIndex = -1;
TEMP = listIndex;
}
System.out.println("list index : " + listIndex);
}
enter code here
This is the getView method of adapter class:
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView = inflater.inflate(R.layout.manage_parameter_list_element,
parent, false);
TextView textView = (TextView) rowView
.findViewById(R.id.parameter_textView);
textView.setText("something");
TextView textView2 = (TextView) rowView
.findViewById(R.id.parameter_range_textView);
textView2.setText("something more");
if(position == SelectParameterActivity.TEMP)
// SelectParameterActivity is the class whose code I've written above
{
((RadioButton) rowView.findViewById(R.id.parameter_radioButton))
.performClick();
}
return rowView;
}
Under normal conditions the switch between radio buttons is fine
Now the problem is, consider this scenario:
I select option1....move down(so that option1 is not on screen anymore)....move up(option1 is visible again)...select option2(or any other apart from 1st)
Now the 1st option does'nt get deselected..
To deselect option1 I have to click on it twice.
FYI I've tried the performClick() method which does not work due to IllegalSateException.
Every time getView() is called you inflate a new View. This method gets called a lot! You cannot rely on the state of your radio button being stored/saved in the view. When the user clicks on a radio button, you need to save this information as part of your data, not in the view. Then, in getView() you need to set the state of the radio button based on the information that you have saved in the data.
I have a List view with a custom adapter (imageviews), in the same activity I have a header and footer, the listView is between those.
What I want is to add a button as the last item of the list view so when you arrive to the last item it appear, i cant add the button outside because it wont scroll
Sorry about my english
Regards
use ListView.addFooterView() to add view as a footer which is visible only in the end of the list:
http://developer.android.com/reference/android/widget/ListView.html#addFooterView(android.view.View)
If you already have a custom adapter class implemented, the solution is rather simple. Based on an xml layout implemented for your list-view rows which contains both a Button and an ImageView, you can hide/display them in the adapter's getView() method based on the index. This is a code sample, which I currently don't have the chance to test and might not be the most efficient solution, but it should give you an idea:
class CustomAdapter extends SimpleAdapter {
[...]
#Override
public int getCount() {
// number of images to be displayed + 1 for the button
return images.length + 1;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
final View row = inflater.inflate(R.layout.row, parent, false);
final ImageView imageView = (ImageView) row.findViewById(R.id.image);
final Button button = (Button) row.findViewById(R.id.button);
if (position == getCount() - 1) {
// The last element
imageView.setVisibility(View.GONE);
// set an OnClickListener on the button or whatever...
} else {
button.setVisibility(View.GONE);
// do your regular ImageView handling...
}
return row;
}
}
Hallo all,
I have a ListView which contains a Button in each line. The following code is part of the getView() Method
public View getView(final int position, View convertView, ViewGroup parent) {
View row = convertView;
TextView tv;
Button saveA_button;
EditText edittext;
FITB_ViewWrapper wrapper;
if (row == null) {
LayoutInflater li = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if (ChooseMode_Act.modeInfo.equalsIgnoreCase("Training")) {
row = li.inflate(R.layout.exercise_for_training_fitb,parent, false);
}else {
row = li.inflate(R.layout.exercise_for_exam_fitb,parent, false);
}
wrapper=new FITB_ViewWrapper(row);
row.setTag(wrapper);
if (ChooseMode_Act.modeInfo.equalsIgnoreCase("Exam")) {
saveA_button=wrapper.getSaveAnswer_Button();
OnClickListener l=new OnClickListener() {
#Override
public void onClick(View v) {
Integer mp=(Integer)v.getTag();
Log.i("mp","my Position is: "+mp);
}
};
saveA_button.setOnClickListener(l);
}
}else {
wrapper=(FITB_ViewWrapper) row.getTag();
}
For my App i need to known to which item the Button belongs to, so i try to detect it. The code
Log.i("mp","my Position is: "+mp);
puts out a message: mp myPosition is: null
I can't understand, why do i get a "null" but not an Integer? How can i find out the Position of an Item in a ListView?
Thanks a lot.
Log.i("mp","my Position is: "+position);
you have the position already !
public View getView(final int position, View convertView, ViewGroup parent) {
The Views in a ListView are reused as you scroll up and down. Thus, setting values in getView often has unintented consequences, like the image that you meant to set for item number 5 appearing in item number 10, 15 and 20 also.
To avoid this, if you want to set properties in getView you need to make sure you set or unset them for each view.
I'm not sure what exactly you are trying to accomplish with your code, but it might help to move the setTag outside of the if statement, to make sure you are setting it each time that a view is used.