74 lines
2.0 KiB
JavaScript
74 lines
2.0 KiB
JavaScript
import _ol_Map_ from '../src/ol/Map.js';
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import _ol_View_ from '../src/ol/View.js';
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import _ol_events_condition_ from '../src/ol/events/condition.js';
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import GeoJSON from '../src/ol/format/GeoJSON.js';
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import DragBox from '../src/ol/interaction/DragBox.js';
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import _ol_interaction_Select_ from '../src/ol/interaction/Select.js';
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import TileLayer from '../src/ol/layer/Tile.js';
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import _ol_layer_Vector_ from '../src/ol/layer/Vector.js';
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import _ol_source_OSM_ from '../src/ol/source/OSM.js';
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import _ol_source_Vector_ from '../src/ol/source/Vector.js';
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var vectorSource = new _ol_source_Vector_({
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url: 'data/geojson/countries.geojson',
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format: new GeoJSON()
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});
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var map = new _ol_Map_({
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layers: [
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new TileLayer({
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source: new _ol_source_OSM_()
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}),
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new _ol_layer_Vector_({
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source: vectorSource
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})
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],
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target: 'map',
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view: new _ol_View_({
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center: [0, 0],
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zoom: 2
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})
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});
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// a normal select interaction to handle click
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var select = new _ol_interaction_Select_();
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map.addInteraction(select);
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var selectedFeatures = select.getFeatures();
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// a DragBox interaction used to select features by drawing boxes
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var dragBox = new DragBox({
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condition: _ol_events_condition_.platformModifierKeyOnly
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});
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map.addInteraction(dragBox);
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dragBox.on('boxend', function() {
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// features that intersect the box are added to the collection of
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// selected features
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var extent = dragBox.getGeometry().getExtent();
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vectorSource.forEachFeatureIntersectingExtent(extent, function(feature) {
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selectedFeatures.push(feature);
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});
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});
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// clear selection when drawing a new box and when clicking on the map
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dragBox.on('boxstart', function() {
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selectedFeatures.clear();
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});
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var infoBox = document.getElementById('info');
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selectedFeatures.on(['add', 'remove'], function() {
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var names = selectedFeatures.getArray().map(function(feature) {
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return feature.get('name');
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});
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if (names.length > 0) {
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infoBox.innerHTML = names.join(', ');
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} else {
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infoBox.innerHTML = 'No countries selected';
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}
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});
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