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我想用手指在谷歌地图上画一个叠加层。我已经完成了线的绘制..但是地图也用我的手指移动,所以我不能画得很好,因为当地图也移动时,我只能在我的手指周围画一个小圆圈......

如何禁用地图的移动(拖动)并仍然能够用我的手指绘制和显示叠加层?

我当前的代码如下所示:

public class OverlayMap extends Overlay {
    private List<MapGeoLine> geoLines = new ArrayList<MapGeoLine>();
    private List<GeoPoint> geoPoints;
    private boolean isTouched = false;

    @Override
    public boolean onTouchEvent(MotionEvent motionEvent, MapView mapView) {

        if(motionEvent.getAction() == MotionEvent.ACTION_DOWN){ 
            geoPoints = new ArrayList<GeoPoint>();
            geoPoints.add(mapView.getProjection().fromPixels((int)motionEvent.getX(),(int)motionEvent.getY()));
            isTouched = true;
        }

        if(motionEvent.getAction() == MotionEvent.ACTION_MOVE){
            if(isTouched){
                geoPoints.add(mapView.getProjection().fromPixels((int)motionEvent.getX(),(int)motionEvent.getY()));
            }
        }

        if(motionEvent.getAction() == MotionEvent.ACTION_UP){
            if(isTouched){
                geoPoints.add(mapView.getProjection().fromPixels((int)motionEvent.getX(),(int)motionEvent.getY()));
            }           
            isTouched = false;
        }   

        return super.onTouchEvent(motionEvent, mapView);
    }

    @Override
    public void draw(Canvas canvas, MapView mapView, boolean shadow) {  

        if(geoPoints != null && geoPoints.size() > 1 && !isTouched){
            Paint mPaint = new Paint();
            mPaint.setStrokeWidth(2); 
            mPaint.setStyle(Paint.Style.STROKE);
            mPaint.setAntiAlias(true); 

            Projection projection = mapView.getProjection();

            Point from = new Point();   
            Point to = new Point();
            Path p = new Path();

            projection.toPixels(geoPoints.get(0), from);            

            for(int i = 1; i < geoPoints.size(); i++){          
                projection.toPixels(geoPoints.get(i), to);
                p.moveTo(from.x, from.y);
                p.lineTo(to.x, to.y);
                from.set(to.x, to.y);               
            }  

            canvas.drawPath(p, mPaint);
            mapView.invalidate();
        }

        super.draw(canvas, mapView, shadow);
    }

}
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1 回答 1

0

onTouchEvent()您需要从处理时返回 trueMotionEvent并且不希望它被其他任何人处理。

否则,您返回 false,并且该事件将由MapView导致地图移动的结果进行处理。

问候。

于 2012-11-24T18:34:09.477 回答