Question

I have a class as follows:

public class Element extends Activity
{
public float mX;
    public float mY;
 public void animate(long elapsedTime) 
    {
        mX += mSpeedX * (elapsedTime / 20f);
        mY += mSpeedY * (elapsedTime / 20f);
        setmX(mX);
        setmY(mY);
        checkBorders();
    }
public void setmX(float mX) 
{
Log.i("this.mX","mY at setmX read is :"+this.mX );      **//Line 1**
        this.mX = mX;
    }
public float getmX() {
        Log.i("mX","mX in getmX read is :"+mX );    **//Line 2**
        return mX;
    }

    public void setmY(float mY) {

        this.mY = mY;
        Log.i("this.mY","mY at setmY read is :"+this.mY );  **//Line 3**
    }

    public float getmY() {
        Log.i("mY","mY in getY read is :"+mY );    **//Line 4**

        return mY;
    }
}

I have another class

public class Panel extends SurfaceView implements SurfaceHolder.Callback
{
int x = 100;
    int y = 0;
public float xval;
    public float yval; 
@Override
    public boolean onTouchEvent(MotionEvent event) 
    {
        Element element = new Element();
        float x = event.getX();
        float y = event.getY();
        Log.i("x","x in panel is :"+x);
        //toast tos = new toast();

        xval = element.getmX();
        Log.i("xval","xval in playactivity obtained is :"+xval );   **//Line 5**
        yval = element.getmY();
        Log.i("yval","yval in playactivity obtained is :"+xval );    **//Line 6**
return super.onTouchEvent(event);
}

Lines 2, 4, 5, and 6 are showing values as zero. Which I don’t want to. Below is the logcat image.

Have I made error in the access Specifiers?

Answer 1

• You should not create an object of Activity class (in you class Element class) in another class. Please go through the Application fundamentals
• Though you are creating an object of Element class in the Panel class, you never called setter method setmX() and setmY() to set the values. You are directly calling the getter methods which returns you the default values.