CODEWITHSUNDEEP
javaandroidarraysobject
Intern87
Intern87

Reputation: 479

Loading Array values into classes

I am dynamically creating objects in the program and populating them from an array.xml. In the array.xml I have a series of tools and values and I need to load these into the class values for each item.

Here is what I have in the class;

public class ToolImporter extends Application{

public static Tool[] tools;
private String[] aTool;
private int i;

public ToolImporter() {

    aTool = getResources().getStringArray(R.array.tools); //null pointer?

    // TODO Auto-generated constructor stub
}

and this is my array.xml;

    <array name="tools">
        <item name="SAW">
            <id>1</id>
            <image>R.drawable.image_saw100x60px</image>
            <boxX>100</boxX>
            <boxY>100</boxY>
            <worktopX>200</worktopX>
            <worktopY>200</worktopY>
        </item>
        <item name="SCREWDRIVER">
            <id>2</id>
            <image>R.drawable.image_screwdriver100x60px</image>
            <boxX>150</boxX>
            <boxY>100</boxY>
            <worktopX>250</worktopX>
            <worktopY>200</worktopY>
        </item>
        <item name="HAMMER">
            <id>3</id>
            <image>R.drawable.image_hammer100x60px</image>
            <boxX>200</boxX>
            <boxY>100</boxY>
            <worktopX>300</worktopX>
            <worktopY>200</worktopY>
        </item>
    </array>

However, it throws a null pointer on the "//null pointer?" line. Can anyone offer advice on what i'm doing wrong to import it?

Upvotes: 0

Views: 133

Answers (3)

Vasudev
Vasudev

Reputation: 1996

Make a 'Context' field in ToolImporter class. Pass context from your activity to ToolImporter class in ToolImporter constructor.

Use context field to access getResources()

aTool = context.getResources().getStringArray(R.array.tools);

Upvotes: 0

Sergio
Sergio

Reputation: 655

Create field variables in your Application class and then initialize them inside the onCreate method within your main activity class.

Upvotes: 1

Woot4Moo
Woot4Moo

Reputation: 24326

According to this post:

You shouldn't call getResources() unless onCreate() callback has been triggered.

public class StackStackActivity extends Activity 
{

    String[] myArray = getResources().getStringArray(R.array.glenns); // This returns null

    public StackStackActivity()
    {

        myArray = getResources().getStringArray(R.array.glenns); // This returns null also
    }

    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        myArray = getResources().getStringArray(R.array.glenns); // Returns an array from resources
    }
}

Upvotes: 1

Related Questions