About Baseadapter and Simpleadapter

For a long time did not get Android, really unfamiliar. The sudden whims of win10 did not say anything about the trouble for Android studio. Feel the android thing too much to learn, gradual thinking let me search the import is what

A: In simple terms is import, Java has many methods you can use directly, but is encapsulated in each package (class) Inside, you need the pilot package, in order to use the method in this package, such as sort (int[] a) This method is the int[] array in ascending order, descending array of numbers, But you have to import java.util.Arrays first, probably this means, of course, it can be imported into your own package, or you write your own method (similar to include Add header file, in order to use the function inside, you can also customize the header file)

I got simpleadapter and baseadapter this afternoon, let's write these two components.

Baseadapter:

ListView mylist;//Declares a ListView

MyList = (ListView) Findviewbyid (r.id.mylist);//Then identify the component by looking for it with myList to use this component and its class method


There are several classes of methods used by Baseadapter: GetCount (); GetItem (); Getitemid (); GetView ();

public int GetCount ()
{
    The return value of the method controls the number of adapter list items
    return 40;
}

Public Object getItem (int position)
{
    Return null;//Set the contents of the Position list item
}

public long getitemid (int position)
{
    Return position;//value as the ID of the number of list items
}

GetView (int position);//The method determines the list item component position

Override this method, and the view returned by the method will be used as a list box
@Override
Public View GetView (int position
        , View Convertview, ViewGroup parent)
{
    Create a linearlayout and add two components to it
    LinearLayout line = new LinearLayout (mainactivity.this);
    Line.setorientation (0);//Set the horizontal trend here, because the text is on the right side of the picture
    
    ImageView image = new ImageView (mainactivity.this);//New Picture view
    Image.setimageresource (R.drawable.ic_launcher);//OK picture
    
    TextView Text = new TextView (mainactivity.this);//New Text view
    Text.settext ("+" + (position +1) + "list items");//Set display text
    Text.settextsize (20);//Set display text size
    Text.settextcolor (color.red);//Set display text color
    
    Line.addview (image);//Add new two components within the linear layout
    Line.addview (text);
    Returning LinearLayout instances
    return line;
}

Complements LinearLayout linear layout knowledge. Copy

2. Linerlayout Linear layout:
4. This layout means that the control elements inside this are explicitly linear,
6. We can specify how the linear layout is displayed by setorientation (int orientation).
8. The values are: horizontal (0), VERTICAL (1). The default is horizontal. We are associated with it
10. You can also specify it through Android:orientation in the layout file. In the same vein, the values are: horizontal,
12. Vertical
14. LinearLayout is a linear layout control that contains child controls that are arranged in a horizontal or vertical manner.
16. When all widgets or other containers are arranged in a relative position, some controls will be missing or disappear when the boundary is exceeded.
18. cannot be fully displayed. So when you're vertically aligned, there's only one widget or container for each row, no matter how wide they are.
20. , and the horizontal arrangement is that there will be only one row high (height of the highest child control plus border height).
22. LinearLayout keeps the widgets or container between them and aligns with each other.
24. (relative to the right, middle, or left of a control).

Simpleadapter:

About Baseadapter and Simpleadapter