I use below code for get data of one row
View vListSortOrder;
vListSortOrder=getListView().getChildAt(MyPositionOfRow);
TextView edit=(TextView)vListSortOrder.findViewById(R.id.MyLabelId);
Toast.makeText(getApplicationContext(), edit.getText(), 1).show();
But My problem is item that not shown in the listView
for Ex: I have 20 item .In MyPhone Screen 10 item of ListView displays.
when MyPositionOfRow set to 0_9 not problem.
when MyPositionOfRow set to 10 or above my program will be crash
How fix it?
Or other way to get data of one row in listView.
You have to use Adapter for interaction with ListView
Your application is crashing, because during UI execution in memory existed only 9 items of ListView.
If you will scroll list to the up - upper item moves to the bottom for memory reducing. And we have to use adapter for correct changing of the item's content.
Really nice article you can find here:
http://www.vogella.com/articles/AndroidListView/article.html
Related
I am having a custom list view. In general it shows some 5-6 data depending to the data. i want a small message in the end of a ListView saying "End of list of results". How to achieve that?
Use addFooterView method of ListView.
I'm using Android Studio, and I have a listView that musts display an important amount of items. showing all of these items have a huge impact on performances. SO I would like to show them 10 by 10, and with a button show the 10 next items. After some researches, I found this android How to limit list items display in ListView and a button show more and this How to limit list items display in ListView by 10 and next 10after clicking next button. But these didn't lead me to a success. The 1st link looks easier but I didn't know where to put the code samples to make it work. Thanks for help !
You dont need to show "Load More" Button always. You can use Android's Recycler View for this. It will load only the data which can be shown on screen. Rest of the data will be loaded as you scroll down. And the view which is scrolled up (Vanishing views) are recycled automatically.
Check this links
https://developer.android.com/training/material/lists-cards.html
https://guides.codepath.com/android/using-the-recyclerview
https://www.binpress.com/tutorial/android-l-recyclerview-and-cardview-tutorial/156
First link question have a simple answer, If you made a custom adapter for populating listview then there will be a getCount() method which will return the number of items you want to show on listview. if you have not getCount() method then simply override it.
Link
there i(variable) have that value which number if items you want to show on listview, on refresh button click increment the value of i(variable) that will again refresh the whole listview and add the total number of items in listview which is the value of i(variable)
I have a situation involving animation of listview's item appearances.
I have a few views in a ScollView , the last of which is the listview. I have attached an appearence animation of the row (a fade in animation).
The problem I have is that when the screen is loaded , the getView() of listview already executes for the initial items , even though the listview is not currently in view.
Hence when a user scroll downs , he sees the list plainly.
I am unsure how to go about this situation . Is there any callback that can be invoked when a row from a listview becomes visible on screen ? .
Yes there is a callback (OnScrollChangeListener), first visible index and last visible index etc. You can achieve what you are trying to using combination of these.
But you need to try that yourself first. No one can simply write a code for you.
You can learn about listview here
EDIT
It's on swedish, but this is what i got with list view.
Every listview item has a empty Linearlayout that i add a view to when i press the down arrow button. the problem is that every fifth item gets this or i can only click on the first 5.
I dont get why they make ListView so complicated. i want to be able to get a child that is in the list without seening it!
The Problem
My way to add the view makes every fifth item to add the view when i only want one position to have this "Mängd" row.
Why Can i only edit listitems when they are visible on the screen.
The child will be static at 5 items even though i got like 20 item....
Is there any way to only say that item 1 will have this and not
position - firstvisibleposition
i think this is the problem with the listview
My code is not understandable at the time because of other things so i hope you get my problem anyways.
This is my main question
It seems like the thing i add to position 0 also happens to 6 and 12 Why is ListView this wierd ?
I have created a custom ListView.. every element of my ListView constructing from a layout.
My layout will have some TextViews and a ToggleButton. My ListView will have some 50 elemnts and my device screen can show 2 elements at a time.
Now if we select ToggleButton on a Item and scroll down my ListView , the selected item will be out of screen and when I come back to the previous selected item I am observinf that selection for that toggle button is gone.
I know that this is a normal behavior in android that It will construct the elements which is currently displaying.
But I want to keep that value.. Is there any way that we preserve selection. or can I tell ListView to donot construct every time.. memory is a not a issue for my application.
Please let me know if there's any good solution for this.
You could store the states of the checkbox in a map with the position as the key. So whenever the list reloads after scroll, it loads based on the hashmap state. You should write this logic in the getView()