android活动中的多个视图对象实例

Question

我有两个在这样的活动中创建的自定义视图对象。

public class Statistics extends Activity {

   GraphWindow graph1; 
   GraphWindow graph2;

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

       graph1 = (GraphWindow) findViewById(R.id.graph1);
       graph2 = (GraphWindow) findViewById(R.id.graph2);

   ...

}

然而，它们似乎充当一个实例，因此graph1的公共方法也将在图2上执行。我是否需要以某种方式将每个图形视图作为新实例启动？我会在哪里这样做？

修改

这是（浓缩的）GraphWindow类：

public class GraphWindow extends View {

//draw data
public ArrayList<DataPoint> data = new ArrayList<DataPoint>();

//set height
public int graphHeight = 0;

public int indexStart = 0;
public int indexFinish = 0;

public boolean isTouched = false;
public boolean isDraggable = false;

public GraphWindow(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}

public GraphWindow(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public GraphWindow(Context context) {
    super(context);
}

public void setGraphHeight(int graphHeight) {
    this.graphHeight = graphHeight;
}

public void isDraggable(boolean isDraggable) {
    this.isDraggable = isDraggable;
}

public void panBox(MotionEvent event) {
    rectX = (int)event.getX();
    rectW = this.getWidth()/5 + rectX;
    this.postInvalidate();
}

public void clearData() {
    this.data.clear();
}

@Override
public void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    ...
}

@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

    ...

}

}

特别是clear数据方法将在graph1和graph2上运行。