So the getView() method of your custom adapter should contain logic to determine whether the row at a certain position should be coloured red or white, and set the background colour of the TextView accordingly. So when the row View is reused, you set the properties of the ViewHolder elements with the correct data, or properties e.g. Basically, a ViewHolder structure is created, to contain only those elements of the row View which need to change e.g. The user may drag the 'thumb' back and forth to choose the selected option, or we can simply tap to toggle the state of. It is mainly used to display the on and off state of an option, which looks like a simple slider control to the user. You should also consider using the 'Viewholder' pattern, because inflating a View and calling findViewById() is expensive and will slow down your list scrolling performance. In Android Studio Switch is a two-state toggle switch widget that can be used to select between two options. The method getView() is called on your adapter, which should return the correct view for a row. Yes your custom adapter will extend from ArrayAdapter. Take some time to think it over, examples do really help, and there are a lot around. Try looking at some examples, but it's important that you do fully understand what's going on, because this is fundamental. It took me a while to actually properly get this concept, and until I did, I was very confused. So the main purpose of getView() is to set the correct state of the View (including all child Views), according to the position. Because the 'convertView' parameter that gets passed in to this method is one that was used on a different row (now off the screen). So if you're scrolling the list, it will be continually called to get rows as they appear on the screen. The purpose of getView() is to return the row View which is being rendered at any time. The No Truncation field attribute should be used on a description field when the list view needs to display the max available text width. So it only gets called when you do a long click on the row. It's in the setOnLongClickListener() method. The code you quoted above has nothing at all to do with the getView() method. You have a few misunderstandings, and unfortunately it's very difficult to explain in the back and forth manner of a forum.
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