求大神帮忙解决android中的编程问题

package mobile.android.first;
import java.util.Random;
import android.graphics.Color;
import android.app.Activity;
import android.os.Bundle;
import mobile.android.first.CircleCanvas.CircleInfo;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
public class main extends Activity {
   
        private CircleCanvas mCircleCanvas;
        @Override
        public void onCreate(Bundle savedInstanceState){
         super.onCreate(savedInstanceState);
         ViewGroup.viewGroup=(ViewGroup)getLayoutInflater().inflate(R.layout.main,null);
         mCircleCanvas=new CircleCanvas(this);
         viewGroup.addView(mCircleCanvas,new LayoutParams(LayoutParams.FILL_PARENT,350));
         setContentView(viewGroup);
        }
        public void onClick_DrawRandomCircle(View view){
         Random random=new Random();
         float randomX=(float)(100+random.nextInt(100));
         float randomY=(float)(100+random.nextInt(100));
         float randomRadius=(float)(20+random.nextInt(40));
         int randomColor=0;
         if(random.nextInt(100)>50){
         randomColor=Color.BLUE;
         }else{
         if(random.nextInt(100)<50){
         randomColor=Color.RED;
         }else{
         randomColor=Color.GREEN;
         }
         CircleInfo circleInfo=new CircleInfo();
         circleInfo.setX(randomX);
         circleInfo.setY(randomY);
         circleInfo.setRadius(randomRadius);
         circleInfo.setColor(randomColor);
         mCircleCanvas.mCircleInfos.add(circleInfo);
         mCircleCanvas.invalidate();
         }
         }
         public void onClick_Clear(View view){
         mCircleCanvas.mCircleInfos.clear();
         mCircleCanvas.invalidate();
         }
        
    }
报错内容:
此行的多个标记
- viewGroup cannot be resolved or is not 
 a field
- 行断点：main [行： 16] - 
 onCreate(Bundle)
- 无法解析 viewGroup，或者它不是字段
如何解决好啊？？？