I have a complex listview. Every item in this listview has three EditTexts and two Checkboxes. Outside the listview is a Button for adding rows to the listview, one for continue and one to go back.
Continue and Back does both call something like:
setContentView(R.layout.stepX);
The problem:
If you press continue and then go back all items from the listview are empty. Is there a easy way to save the input or hold him in ram?
My current workaround is to create a Class for a listitem and if you continue every itemdata is read and saved to an arraylist. If you go back it read the arraylist and rebuild the listitems.
Related
I have created listView with about 20 items.
While navigating through keyboard when it's on last and when user hits down button I'd like it to go to first item.
Just like keyNavigationWraps : bool in QML.
You should not iterate the list views, instead you should keep all that data (price/quantity) in a list and iterate over that if you really need to do that. That list can be used to populate the ListView as well.
I'm new to Android and can't quite figure out the right approach for the problem I'm trying to solve. I have an ExpandableListView with several items. Each item has an EditText, except the last item has a button. The contents of the EditTexts are to be loaded from the database. When the button is clicked or when the activity is navigated away from, I want to save the contents of each EditText to my database.
I'm not sure what to call from the activity's class, what to call from my adapter, and how exactly to access each item appropriately. Code is welcome but not necessary, I'm just looking for guidance on the general approach. Thanks.
I'd recommend putting a method in your adapter called saveAllValues. It iterates through the list of objects in the adapter and saves them to the database. Call this when your button is clicked and in your activity's onStop() method (which is called when the activity is no longer visible).
You should have your activity fetch the values for the item IDs in an AsyncTask in its onCreate method. Then pass the list of id/value pairs to the adapter in its constructor. It should maintain this list so it can go back through it and save the IDs and values to the DB.
Hope my answers in these links help:
Values of counter changes after scrolling ExpendableListView shows how to maintain the list inside the adapter and how to get list from the activity.
Remove the divider view in the expandablelistview last item shows how to make the last child different from the others.
I'm building an android app and I'm trying to replace a list view with another list view if you click a button, like the notifications page on Instagram. On that page, if you click on the top "following" button it will show you a listview of what your followers have liked. If you click on the "you" button it will show you a listview of what people have liked your photos.
Any help would be greatly appreciated!
You can do it by following ways,
1. add Two listviews and can change the visibility as per your requirement.
2. On button click you can load the other data into same list view and can update your adapter in the same list view.
in 1 you have to load two list view at first which will consume more time if data is larger sure you can write a login in asynctask to load list views in background thread.
in 2 you have to update your adapter at the button so you will have to provide some progress bar of dialog for user while you list view is getting update.
You can use either of this whichever suites you best.
Simply , You don't need to switch Listview , you only need to switch adapters .
eg, you can switch to mFollowingAdapter when clicked on Following button and switch to mYouAdapter when you select "You" tab. that's it.
You should write a list, that has a custom adapter. This adapter will be able to display BOTH views you want to display.
If the data to be displayed is the same format (ie. both have an imageview next to a textview), you are in good shape.
When you want to switch to a different list, get the information you would like to display, replace the data in your the collection backing your list, then notify the list that the data has changed, and it should redraw.
So, this might look like:
create ArrayList() with data A
setup List, with this data and display
replace the ArrayList() with data B
call listView.notifyDataSetChanged
You can still do this if the Data A, and Data B have different views, in this case, you would need to handle this logic in your custom adapter.
I want my ListView to work something like the following:
When I press a button (probably from context-menu), I want the user to be able to select more then one item from ListView (probably using check-boxes), but those check-boxes should not be visible before that.
So, the point is, after the user presses a button (let's say "Delete more items"), the listview, should update itself, and appear on every row of the list, a checkbox should appear (allowing me to select the items ID to pass those to server).
How can I achieve that, without having to recreate the list from zero? (how to setVisibility ON, keeping the other content of the ListView as it is, and not doing another request to server).
PS. If you guys, have another better idea, on achieving the Delete More Items, would be much appreciated!
This is just an idea, haven't tried it myself: you build in a checkbox in your listitem layout. Normally, in the getView of your adapter, you set it invisible with
checkBox.setVisibility(8);
When you want to show them, you set some boolean
showBoxes
of your adapter to true, then in the getView oyu don't hide the checkboxes.
Then
notifyDataSetChanged
on the adapter.
Hope it's clear what I mean.
I want to clera the listview item from the screen when pressing the clear all button. So I used the function m_adapter.clear(); It's clearing the items from the screen. But when I again coming back to the app after exit, those views again coming back. I need to clear them permanently. Can anybody help me in this problem?
Code snippet is as follows:
case R.id.deleteAll:{
m_adapter.clear();
}
If you really want to remove and clear your listview permanently your adapter.clear() will not work.
The actual meaning of this method is to clear your listview and not the listview items.
What you actually have to do is to remove all the elements from the array which you are using to populate the listview.
So this is the only way which will ensure you that your listview will not be loaded with data even when come back to your activity and getting out of it.
If not you will have to call your clear() each and every time you enter your activity, thus making it to look like as if there is not data present.
You'll need to clear the source of your listview data, then refresh the listview. That way, when you reopen the activity the data will not be redisplayed as it won't exist anymore.
Eg. If the listview is populated from a database, delete the data from the database, then refresh the listview.