Question

Hi I’m kind of beginner to android OS programming, and I got stuck with a problem, I cant figure out how to do a dynamic background, based on timers (say each 10 seconds a background changes to a different one) I have some code but it comes up with error, here’s a sample:

private static final long GET_DATA_INTERVAL = 10000;
int images[] = {R.drawable.smothie1,R.drawable.omletherb1};
int index = 0;
ImageView img;
Handler hand = new Handler();

public void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    this.setContentView(R.layout.main);
    LinearLayout layout= (LinearLayout)findViewById(R.id.LinearView1);
    hand.postDelayed(run, GET_DATA_INTERVAL);
}

Runnable run = new Runnable() {
    public void run() {
        layout.setBackgroundResource(LinearView1).getDrawable(images[index++]);
        if (index == images.length)
            index = 0;
        hand.postDelayed(run, GET_DATA_INTERVAL);

Any help would be greatly apprieciated 😀 thanks

EDIT: The errors I get are on this line:

layout.setBackgroundResource(LinearView1).getDrawable(images[index++]);

It says that:

-layout cannot be resolved

-the method getDrawable(int) is undefined for the type Object

---

This error:

layout.setBackgroundResource(LinearView1).getDrawable(images[index++]);

It says that:

-layout cannot be resolved

-the method getDrawable(int) is undefined for the type Object

Please help 🙂

Answer 1

I have finally worked it out, after removing a few errors I have came up with this (and its working) :

public class CookBookActivity extends Activity {
/** Called when the activity is first created. */

private static final long GET_DATA_INTERVAL = 1000;
int images[] = {R.drawable.omletherb1,R.drawable.smothie1};
int index = 0;
LinearLayout img;
Handler hand = new Handler();
private LinearLayout layout;

public void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    this.setContentView(R.layout.main);
    layout = (LinearLayout)findViewById(R.layout.main);
    hand.postDelayed(run, GET_DATA_INTERVAL);

    Typeface tf2 = Typeface.createFromAsset(getAssets(),
            "fonts/BPreplay.otf");
    TextView tv2 = (TextView) findViewById(R.id.textView2);
    tv2.setTypeface(tf2);


    Typeface tf = Typeface.createFromAsset(getAssets(),
            "fonts/BPreplay.otf");
    TextView tv = (TextView) findViewById(R.id.textView1);
    tv.setTypeface(tf);


    Button mainNext = (Button) findViewById(R.id.nextScreen1);
    mainNext.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
            Intent i = new Intent();
            i.setClassName("com.unKnown.cookbook", "com.unKnown.cookbook.screen1");
            startActivity(i);

        }
    });
}

Runnable run = new Runnable() {
    public void run() {
        layout.setBackgroundDrawable(getDrawable(index++));
        if (index == images.length)
            index = 0;
        hand.postDelayed(run, GET_DATA_INTERVAL);

    }
};

protected Drawable getDrawable(int i) {
    // TODO Auto-generated method stub
    return getResources().getDrawable(images[i%2]);
}

}