Question

I’m trying to implement a ListView on my app, but i’m trying to understand and learn how to achieve it without using XML files, all with java code.

I’m stuck on the inflater part, the mInflater.inflate(); function needs a resource xml file, so, i didn’t understand how to continue without using XML files

I have a ArrayList of strings, and I simply need a ListView that shows a list with these strings of the Arraylist, and a delete Button on the right of the String. If the user press the Button, the item of the List get’s deleted.

Each item of the ListView has two things, a TextView with the String of the ArrayList and a Button to delete it.

If someone can give me code examples i will be grateful.

Thanks

Answer 1

I totally agree with CommonsWare. But the part that you are stuck is the part that you have to create a row “template” for the ListView rows. The inflater is used so as to make a single View out of a complete layout.xml file. So the basic idea is that you create an xml that represents each row and then inflate it through that piece of code.

In your situation, you need to do that through code. Perhaps add a LinearLayout as a parent with orientation=vertical add some width or height properties and then add 2 TextViews so as to be a title and a subtitle with some additional properties. Then you should add them to the LinearLayout and you there you go.

Your LinearLayout is a pile of Views that are dynamically created and have the same effect as inflating all the above code through an xml file.

But I reaaaaally don’t see the point in creating such a fuss over a much faster, easier, straight forwarded, better implemented and not to mention best practice…

EDIT: Somewhere inside your adapter you have: mInflater.inflate(); with the resource that you mention. As I previously said the resource determines how the “template” for each row would be. So a normal xml file that will determine a list row would be something like this:

<LinearLayout android:layout_width="fill_parent"
   android:layout_height="wrap_content" android:orientation="vertical" >
   <TextView ... /> <! --some properties you want to set -->
   <TextView ... /> <! --some properties you want to set -->
</LinearLayout>

This xml produces a 2 line list row for a ListView. With the layout inflater the above xml file returns a View object that contains all the bundle.

So if you want to create it from code, then the snippet would be:

LinearLayout layout = new LinearLayout(context);
//layout set some properties
TextView title = new TextView(context);
//title set some properties
TextView subtitle = new TextView(context);
//subtitle set some properties
layout.add(title);
layout.add(subtitle);

Now instead of inflating the xml to get the contents into a single View object, you have the layout variable in the code snippet that contains all the logic that was previously inflated through the xml.

If you have created a custom ListView adapter before then you should be familiar with creating a custom list row and how it works.

EDIT: sample code for the adapter of the ListView

this is the standart procedure of getView() method of the adapter by inflating a single layout:

@Override
public View getView(int position, View view, ViewGroup viewgroup) {
ViewHolder holder; //our view holder of the row
if (view == null) {
   view = context.getLayoutInflater().inflate(R.layout.static_layout, null);
   holder = new ViewHolder();
   //set the views of the holder
       view.setTag(holder);
} else {
   holder = (ViewHolder) view.getTag();
}
    //rest of implementation of the View
    return view;
}

dynamic implementation:

@Override
public View getView(int position, View view, ViewGroup viewgroup) {
ViewHolder holder; //our view holder of the row
if (view == null) {
       LinearLayout layout = new LinearLayout(context);
       //layout set some properties
       TextView title = new TextView(context);
       //title set some properties
       TextView subtitle = new TextView(context);
       //subtitle set some properties
       layout.add(title);
       layout.add(subtitle);
   //CREATING THE LAYOUT THROUGH CODE

       view = layout; //INSTEAD OF INFLATING A LAYOUT FOR THE ROW I JUST BINDED IT TO THE RECENTLY CREATED LAYOUT 
   holder = new ViewHolder();
   //bind the views of the holder to the views of the layout
       view.setTag(holder);
} else {
   holder = (ViewHolder) view.getTag();
}
    //rest of implementation of the View
    return view;
}