I use ImageLoader, and display image in ListView, when havent image, server give me String "null", i have check:
if(!image.equals("null")) {
imageLoader.displayImage(image, avatar);
}
If not verified, then there should be an empty area, so all ListView item. But if first item .equals("null") , then first image same pattern as last item image, if onStop and onResume Activity, then image first item empty.
Why is this happening? If image.equals("null") then area must be empty.
Use poistion on getView(), Based on the scrolling
Fetch the value
Check if value exists then set value
else null
use ViewHolder effectively
Related
I just created a spinner and make this spinner read from the database. and display them in the spinner. I already did that. But I want to right down the Id of the selected item.
for example : when I select the first raw called (1, tyat abdullah, sergurey )
I need the Id (1) only to be written down without the full record.
I need the Id (1) only to be written down without the full record.
Then when you are doing labels.add, only put the data you want to see
You can also use doctorsList.get(position) within the selection listener, and set the other text view accordingly.
For example, doctorsList.get(position).getId() seems to get the information you are asking for
simply use this to get the selected item index
int index = spinner.getSelectedItemPosition(); //this will give you the seleected item index
is that what you want ?
leme Know :)
I have a spinner and I'm getting its selected item position by MyOnItemSelectedListener. By the time I'm using an array adapter to load items to the spinner. I have loaded the items and it works perfectly. But I have a small problem. When I doesn't select a value then it shows position 0 but it has got the value of 1st array value. As shown in the below image,
What I want to do is when I haven't select a value then it should get any value from array. And when I select 1st item then only it should get 1st array value.
Array is a created from json response so it is not possible to add a item to array manually.
I have used How to make an Android Spinner with initial text "Select One" (aaronvargas's answer) to add slect option to spinner as 1st selection.
How can I achieve this? Any help will be highly appreciated.
You can use the logic like :
int selectedValue = -1;
if(position<=0){
//Means Item not selected
}else{
selectedValue = array[position-1];
}
I think you can use something like I have shown.
if(position==0){
variable = 0;
}else{
//use ur logic here
}
Okay i have one EditText and one spinner.
My goal is if item 1 on spinner selected the EditText visibility is true, and if item 2 selected EditText visibility is false. what the code for reach that goal ?
i use spiner get selected id like this :
String tipe = spiner.getSelectedItem().toString();
if (tipe=="item2"){
//edittext.visible = false; <-- i don't know how to make/what code this visibility become false
}
Use the below
if (tipe.equals("item2")){ // .equals to compare strings
edittext.setVisibiluty(View.INVISIBLE); //set the visibility
}
Use the below according to your needs
visible 0 Visible on screen; the default value.
invisible 1 Not displayed, but taken into account during layout (space is left for it).
gone 2 Completely hidden, as if the view had not been added.
http://developer.android.com/reference/android/view/View.html#setVisibility(int)
use equals() method for comparing of Two String. It will check the content of the String
String tipe = spiner.getSelectedItem().toString();
if (tipe.equals("item2")){
// do what u want here
}
I have a ListView that uses a custom layout that has 5 child View objects (4 TextView and 1 CheckBox) in the custom layout. Only the TextViews are bound, however - the CheckBox has no corresponding field in the database. The purpose of the CheckBox is simply to identify which of the items being displayed I would like to process in "the next step". I'm using a custom ViewBinder to assign the text values correctly (because some of the values from the DB are dates, etc).
Part of the user interface is three buttons - 'All', 'None', and 'Invert' that I use to toggle the status of each item in the list. For the 'All' button, for example, I do this with the following code (which I now know is NOT correct - I include it to show what I'm trying to do):
ListAdapter la = getListAdapter();
ListView lv = getListView();
int iCount = la.getCount();
for(int i=0; i<iCount; i++)
{
View vv = lv.getChildAt(i);
CheckBox cb = (CheckBox) vv.findViewById(R.id.ledgerItemCheckBox);
cb.setChecked(true);
}
This works fine as long as the number of items in the list doesn't exceed the list size so that all items are always visible. When I exceed that number, though, the 'getChildAt' function sometimes returns null because (if I understand correctly) it isn't meant to return all of the items in the list, only those items that are visible, which results in a NullPointerException.
How can I properly set the CheckBox on all views, even if they aren't visible?
Create a pseudo binding to one of your TextView data, create an ArrayList of Boolean objects as your back end for the checkboxes. Please note an ArrayList may not be the best data structure for your application. Fill the ArrayList with booleans set to the initial value of the corresponding position of your Cursor's data set. When you're binding use the ArrayList as the back end data. When you select all, none, or invert, update the Boolean objects in the ArrayList then call notifyDataSetChanged() on your SimpleCursorAdapter.
Addition ah, the other half of the problem, yes, use the onClickListener for the CheckBoxes but use the same listener, don't create a new object for each. Use the getPositionForView() method to get your position and update the underlying data.
How will i go about saving the state of a listview item during scrolling, so that the recycler does not use it when displaying the next row being. i basically have a listview with 4 textviews and one of the textview is displayed based on a condition, derived from a database. For clarity sake, i will call that dependant textview "A".
my problem is that, simplest case: if "A" is being displayed for only the first item or any other row in the list and its not displayed anywhere else, when scrolling, "A" is displayed on other rows that should not have it. i understand the concept of listview reusing rows, but i can't figure out how to save it on an item, so it doesn't get used in another row. Here is a simplified code with just 2 textview:
holder.viewItemName = (TextView)view.findViewById(R.id.nameId);
holder.viewdescriptionStatus = (TextView)view.findViewById(R.id.viewdescriptionId);
int namecolumn = c.getColumnIndex(DBAdapter.NAME);
String name = c.getString(namecolumn);
holder.viewItemName.setText(name);
int description = c.getColumnIndex(DBAdapter.description);
String descriptionstatus = c.getString(description);
/*problem am having here*/
if(description != null){
holder.viewdescriptionStatus.setText("description available");
holder.viewdescriptionStatus.setTextColor(Color.BLUE);
}
as you can see, am using a viewHolder, but i have come to realise that viewHolder doesn't hold the logic as well. i don't know how to save the state of the holder.viewdescriptionStatus based on that condition. Most of the examples i have seen are based on checkboxes. Please anyone with ideas?.. it will be really appreciated.
P.S : i am using bindView() and newView() since i am using an SQLdatabase and SimpleCursorAdapter. i have the same issue with clicking, but i want to solve the scrolling part first. Thank you for your time.
Try this
holder.viewdescriptionStatus.setText(description != null ? "description available" : "");