PROSAGA码农传奇-时空索引-在ArcGIS Runtime for Android中清除MapView图层

<div class =“post-text”itemprop =“text”>
  <P>
    <a href="https://developers.arcgis.com/android/10-2/api-reference/reference/com/esri/android/map/MapView.html#removeAll()" rel="nofollow noreferrer">
       <code>
        MapView.removeAll()
      </code>
    </A>
     从地图中删除所有图层。那不是你想要的。
  </p>
  <P>
    相反，尝试循环遍历
     <code>
      MapView
    </code>
    的图层和每个类型的图层
     <code>
      GraphicsLayer
    </code>
     （但不是类型
     <code>
      ArcGISFeatureLayer
    </code>
    ），删除图层或从图层中删除图形。做这样的事情：
  </p>
   <pre>
    <code>
      private void somewhereInYourExistingCode() {
    ...
    for (Layer layer : map.getLayers()) {
        clearGraphics(layer);
    }
    ...
}

private void clearGraphics(Layer layer) {
    /**
     * ArcGISFeatureLayer extends GraphicsLayer, but what you're
     * probably looking for is GraphicsLayer objects that are
     * not of type ArcGISFeatureLayer.
     */
    if (layer instanceof GraphicsLayer && !(layer instanceof ArcGISFeatureLayer)) {
        // You can call map.removeLayer(layer), or...
        ((GraphicsLayer) layer).removeAll();
    } else if (layer instanceof GroupLayer) {
        GroupLayer groupLayer = (GroupLayer) layer;
        for (Layer sublayer : groupLayer.getLayers()) {
            // Recursive call
            clearGraphics(sublayer);
        }
    }
}

</code>
  </pre>
</DIV>