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Thread: problem with @Override in onDraw

  1. #1
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    Default problem with @Override in onDraw

    I can not figure out why I am getting a "The method OnDraw(Canvas) of type DrawStuffActivity.MyView must override or implement a supertype method" error, any help would be greatly appreciated



    import android.app.Activity;
    import android.content.Context;
    import android.graphics.Canvas;
    import android.graphics.Color;
    import android.graphics.Paint;
    import android.graphics.Rect;
    import android.os.Bundle;
    import android.util.DisplayMetrics;
    import android.view.MotionEvent;
    import android.view.View;
    import android.view.View.OnTouchListener;
     
    public class DrawStuffActivity extends Activity implements OnTouchListener
    {
    	MyView myView;
    	int numberOfFingers = 0; 
    	float oldX[] = new float[2],
    			oldY[] = new float[2];
    	Rect rectangle = new Rect(0, 0, 100, 100);
    	DisplayMetrics metrics = new DisplayMetrics();
     
    	@Override
    	protected void onCreate(Bundle savedInstanceState) 
    	{
    		super.onCreate(savedInstanceState);
     
    		myView = new MyView(this);
    		setContentView(myView);
    		myView.setOnTouchListener(this);
     
    		getWindowManager().getDefaultDisplay().getMetrics(metrics);
    	}
     
     
    	@Override
    	public boolean onTouch(View view, MotionEvent event) 
    	{
    		switch (event.getActionMasked() )
    		{
    		case MotionEvent.ACTION_DOWN:
    			numberOfFingers = 1;
    			oldX[0] = event.getX(0);
    			oldY[0] = event.getY(0);
    			break;
    		case MotionEvent.ACTION_POINTER_DOWN:
    			numberOfFingers = 2;
    			oldX[1] = event.getX(1);
    			oldY[1] = event.getY(1);
    			break; 
    		case MotionEvent.ACTION_MOVE:
    			handleMove(event);
    			break;
    		case MotionEvent.ACTION_POINTER_UP:
    		case MotionEvent.ACTION_UP:
    			numberOfFingers--;
    			break;
    		}
     
    		view.invalidate();
    		return true;
    	}
     
     
    	float newX[] = new float[2], newY[] = new float[2];
    	int xChange[] = new int[2], yChange[] = new int[2];
     
    	int diffX, diffY;
    	int newLeft = rectangle.left, 
    			newTop = rectangle.top, 
    			newRight = rectangle.right,
    			newBottom = rectangle.bottom;
     
     
     
     
    	void handleMove(MotionEvent event)
    	{
    		newX[0] = Math.round(event.getX(0) );
    		newY[0] = Math.round(event.getY(0) );
    		xChange[0] = Math.round(newX[0] - oldX[0] );
    		yChange[0] = Math.round(newY[0] - oldY[0] );
    		oldX[0] = newX[0];
    		oldY[0] = newY[0];
     
    		switch (numberOfFingers)
    		{
    		case 1:
    			newLeft = rectangle.left + xChange[0];
    			newTop = rectangle.top + yChange[0];
    			newRight = rectangle.right + xChange[0];
    			newBottom = rectangle.bottom + yChange[0];
     
    			if (newLeft < 0 || newRight > metrics.widthPixels)
    			{
    				newLeft = rectangle.left;
    				newRight = rectangle.right;
    			}
    			if (newTop > 0 || newTop > metrics.heightPixels)
    			{
    				newTop = rectangle.top;
    				newBottom = rectangle.bottom;
    			}
     
    			rectangle = new Rect(newLeft, newTop, newRight, newBottom);
     
    			break;
     
    		case 2:
    			newX[1] = Math.round(event.getX(1) );
    			newY[1] = Math.round(event.getY(1) );
     
    			diffX = Math.abs(Math.round(newX[1] - newX[0])) - Math.abs(Math.round(oldX[1] - oldX[0]));
    			diffY = Math.abs(Math.round(newY[1] - newY[0])) - Math.abs(Math.round(oldY[1] - oldY[0]));
     
    			oldX[1] = newX[1];
    			oldY[1] = newY[1];
     
    			newLeft = rectangle.left - diffX / 2;
    			newTop = rectangle.top - diffY / 2;
    			newRight = rectangle.right - diffX / 2;
    			newBottom = rectangle.bottom - diffY / 2;
    			rectangle = new Rect(newLeft, newTop, newRight, newBottom);
     
    			break;
    		}
     
     
     
    	}
     
    	class MyView extends View
    	{
    		Paint whitePaint = new Paint();
     
    		MyView(Context context)
    		{
    			super(context);
    			whitePaint.setColor(Color.WHITE);
    		}
     
    		@Override
    		public void OnDraw(Canvas canvas) 
    		{
    			canvas.drawRect(rectangle, whitePaint);
    		}
    	}
    }


  2. #2
    Administrator copeg's Avatar
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    Default Re: problem with @Override in onDraw

    Check the API for the correct method signature - hint, java is case sensitive

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