能够在黑莓地图中显示多个位置，但地图的位置是固定的。我无法放大和缩小

Question

大家好，我尝试使用自定义MapField在地图上显示几个loacations。我可以在地图上显示位置。但无法移动图像，也无法放大和缩小。我尝试使用自定义MapField，但它仍然不适合我.. 这是我的代码

class CustomMapField extends MapField 
{
Bitmap mIcon;
XYRect mDest;
public void moveTo(Coordinates coordinates) 
{
    super.moveTo(coordinates);
    mDest = null;
}
protected void paint(Graphics graphics) 
{
    super.paint(graphics);
    if (null != mIcon) 
    {
        if (null == mDest) 
        {
            XYPoint fieldOut = new XYPoint();
            convertWorldToField(getCoordinates(), fieldOut);
            int imgW = mIcon.getWidth();
            int imgH = mIcon.getHeight();
            mDest = new XYRect(fieldOut.x - imgW / 2,fieldOut.y - imgH, imgW, imgH);
        }
        graphics.drawBitmap(mDest, mIcon, 0, 0);
    }
}
}

Answer 1

放大和缩小我使用了这个 -

 public boolean keyChar(char key, int status, int time) 
{    
    if(key=='i')
    {
        mMapField.setZoom(Math.max(mMapField.getZoom() - 1,mMapField.getMinZoom()));
    }
    else if(key=='o')
    {
        mMapField.setZoom(Math.min(mMapField.getZoom() + 1,mMapField.getMaxZoom()));
    }
    return super.keyChar(key, status, time);
}