Aw5739 Add ngx openlayers

projects/ngx-openlayers/src/lib/layers/layer.component.ts

@@ -0,0 +1,67 @@
+import { Directive, Input, OnChanges, OnDestroy, OnInit, SimpleChanges } from '@angular/core';
+import { Event } from 'ol/events';
+import { Extent } from 'ol/extent';
+import { MapComponent } from '../map.component';
+import { LayerGroupComponent } from './layergroup.component';
+
+@Directive()
+export abstract class LayerComponent implements OnInit, OnChanges, OnDestroy {
+  @Input()
+  opacity: number;
+  @Input()
+  visible: boolean;
+  @Input()
+  extent: Extent;
+  @Input()
+  zIndex: number;
+  @Input()
+  minResolution: number;
+  @Input()
+  maxResolution: number;
+
+  @Input()
+  prerender: (evt: Event) => void;
+  @Input()
+  postrender: (evt: Event) => void;
+
+  instance: any;
+  componentType = 'layer';
+
+  constructor(protected host: MapComponent | LayerGroupComponent) {}
+
+  ngOnInit() {
+    if (this.prerender !== null && this.prerender !== undefined) {
+      this.instance.on('prerender', this.prerender);
+    }
+    if (this.postrender !== null && this.postrender !== undefined) {
+      this.instance.on('postrender', this.postrender);
+    }
+    this.host.instance.getLayers().push(this.instance);
+  }
+
+  ngOnDestroy() {
+    this.host.instance.getLayers().remove(this.instance);
+  }
+
+  ngOnChanges(changes: SimpleChanges) {
+    const properties: { [index: string]: any } = {};
+    if (!this.instance) {
+      return;
+    }
+    for (const key in changes) {
+      if (changes.hasOwnProperty(key)) {
+        properties[key] = changes[key].currentValue;
+        if (key === 'prerender') {
+          this.instance.un('prerender', changes[key].previousValue);
+          this.instance.on('prerender', changes[key].currentValue);
+        }
+        if (key === 'postrender') {
+          this.instance.un('postrender', changes[key].previousValue);
+          this.instance.on('postrender', changes[key].currentValue);
+        }
+      }
+    }
+    // console.log('changes detected in aol-layer, setting new properties: ', properties);
+    this.instance.setProperties(properties, false);
+  }
+}