/**
* 设置路线数据。
*
* @param line 路线数据
*/
public void setData(WalkingRouteLine line) {
    mRouteLine = line;
}

@Override
public final List<OverlayOptions> getOverlayOptions() {
    if (mRouteLine == null) {
        return null;
    }

    List<OverlayOptions> overlayList = new ArrayList<OverlayOptions>();
    if (mRouteLine.getAllStep() != null
            && mRouteLine.getAllStep().size() > 0) {
        for (WalkingRouteLine.WalkingStep step : mRouteLine.getAllStep()) {
            Bundle b = new Bundle();
            b.putInt("index", mRouteLine.getAllStep().indexOf(step));
            if (step.getEntrance() != null) {
                overlayList.add((new MarkerOptions()).position(step.getEntrance().getLocation())
                        .rotate((360 - step.getDirection())).zIndex(10).anchor(0.5f, 0.5f)
                        .extraInfo(b)
                        .icon(BitmapDescriptorFactory.fromAssetWithDpi("Icon_line_node.png")));
            }
            // 最后路段绘制出口点
            if (mRouteLine.getAllStep().indexOf(step) == (mRouteLine
                                                                    .getAllStep().size() - 1)
                    && step.getExit() != null) {
                overlayList.add((new MarkerOptions()).position(step.getExit().getLocation())
                        .anchor(0.5f, 0.5f).zIndex(10)
                        .icon(BitmapDescriptorFactory.fromAssetWithDpi("Icon_line_node.png")));
            }
        }
    }
    // starting
    if (mRouteLine.getStarting() != null) {
        overlayList.add((new MarkerOptions()).position(mRouteLine.getStarting().getLocation())
                .icon(getStartMarker() != null ? getStartMarker()
                        : BitmapDescriptorFactory.fromAssetWithDpi("Icon_start.png"))
                .zIndex(10));
    }
    // terminal
    if (mRouteLine.getTerminal() != null) {
        overlayList
                .add((new MarkerOptions())
                        .position(mRouteLine.getTerminal().getLocation())
                        .icon(getTerminalMarker() != null ? getTerminalMarker() :
                                BitmapDescriptorFactory
                                        .fromAssetWithDpi("Icon_end.png"))
                        .zIndex(10));
    }

    // poly line list
    if (mRouteLine.getAllStep() != null
            && mRouteLine.getAllStep().size() > 0) {
        LatLng lastStepLastPoint = null;
        for (WalkingRouteLine.WalkingStep step : mRouteLine.getAllStep()) {
            List<LatLng> watPoints = step.getWayPoints();
            if (watPoints != null) {
                List<LatLng> points = new ArrayList<LatLng>();
                if (lastStepLastPoint != null) {
                    points.add(lastStepLastPoint);
                }
                points.addAll(watPoints);
                overlayList.add(new PolylineOptions().points(points).width(15).dottedLine(true)
                        .customTexture(getWalkRoadCustomTexture()).zIndex(0));
                lastStepLastPoint = watPoints.get(watPoints.size() - 1);
            }
        }

    }

    return overlayList;
}

public BitmapDescriptor getWalkRoadCustomTexture() {
    return BitmapDescriptorFactory.fromAsset("Icon_road_blue_arrow.png");
}                  
                

/**
* 将步行路线添加到地图上
*/
public final void addToMap() {
    if (mBaiduMap == null) {
        return;
    }

    List<OverlayOptions> overlayOptions = getOverlayOptions();
    if (overlayOptions != null) {
        mOverlayOptionList.addAll(getOverlayOptions());
    }

    for (OverlayOptions option : mOverlayOptionList) {
        mBaiduMap.addOverlay(option)
    }
}
                

/**
* 将步行路线调整到地图显示的最佳视野范围内
*/
public void zoomToSpanPaddingBounds(int paddingLeft, int paddingTop, int paddingRight,
    int paddingBottom) {
    if (mBaiduMap == null) {
        return;
    }
    if (mOverlayList.size() > 0) {
        LatLngBounds.Builder builder = new LatLngBounds.Builder();
        for (Overlay overlay : mOverlayList) {
            // polyline 中的点可能太多，只按marker 缩放
            if (overlay instanceof Marker) {
                builder.include(((Marker) overlay).getPosition());
            }
        }

        mBaiduMap.setMapStatus(MapStatusUpdateFactory
                .newLatLngBounds(builder.build(), paddingLeft, paddingTop, paddingRight,
                        paddingBottom));
    }
}