I'm trying to find any documentation to help me understand and use the leaflet-geopackage plugin. what I want to do is use the full potential of the .gpkg file as a database and query only part of the layer. is that even possible? or do I have to just hide the parts I don't want to show?

Clarification, I'm only talking about feature layers, not tiles.
loaded with the example code from their github:

var rivers = L.geoPackageFeatureLayer([], {
     geoPackageUrl: 'http://ngageoint.github.io/GeoPackage/examples/rivers.gpkg',
     layerName: 'rivers',
     style: {color: 'green'}
  • If you are trying to find documentation, here it is: ngageoint.github.io/geopackage-js/jsdoc/… – Stefan Oct 21 '18 at 16:43
  • that's for gopackage.js and not to the specific leaflet-geopackage. and judging by what's there, you can only query by bounds which is very strange. – Dror Bogin Oct 22 '18 at 3:36

Starting from this: https://github.com/ngageoint/geopackage-js/tree/master/leaflet

I can see that the GeoPackageFeatureLayer extends L.GeoJSON and accepts all options for L.GeoJSON in addition to three other options: geoPackageUrl,layerName,nocache. This would leed me to searching here:https://leafletjs.com/reference-1.3.4.html#geojson

The GeoJson layer has a Filter property that might be called before adding one particular layer:

A Function that will be used to decide whether to include a feature or not. The default is to include all features.

Reading from this note: dynamically changing the filter option will have effect only on newly added data. It will not re-evaluate already included features, I take that you will have to have a mechanism for manually updating the added layers to the map.

Coming back to your example, I would try this, updating the feature.properties.property_1 as necessary from the gpk example:

var rivers = L.geoPackageFeatureLayer([], {
     geoPackageUrl: 'http://ngageoint.github.io/GeoPackage/examples/rivers.gpkg',
     layerName: 'rivers',
     filter:function (feature,layer){
       if (feature.properties.property_1 == 'Danube') {return  'true'}
     style: {color: 'green'}

I have also made a JSFiddle with 2 types of filtering the one above, as well as one where property_0 === '6' https://jsfiddle.net/rususorinvick/9ajqhyb3/

|improve this answer|||||
  • 1
    If this solves your question, you should also award the bounty. :) – Stefan Oct 26 '18 at 20:51
  • thanks Stefan for the support. Got the reward. Glad to help! – Sorin RUSU Oct 29 '18 at 9:26
  • sorry, had to test that it works using a cellphone. took some time to verify. – Dror Bogin Oct 29 '18 at 13:32

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