feat: implement #42

Author: keerl

src/ui-mapbox/layers/layer-factory.android.ts

@@ -34,6 +34,15 @@ export class Layer implements LayerCommon {
     public getFilter(): any[] {
         return FilterParser.toJson(this.instance.getFilter());
     }
+
+    public setProperty(name: string, value: any) {
+        const properties = PropertyParser.parsePropertiesForLayer({ [name]: value });
+        this.instance.setProperties(properties);
+    }
+
+    public getProperty(name: string): any {
+        return PropertyParser.propertyValueFromLayer(this.instance, name);
+    }
 }
 
 export class LayerFactory {

src/ui-mapbox/layers/layer-factory.d.ts

@@ -14,4 +14,6 @@ export declare class Layer implements LayerCommon {
     getNativeInstance(): any;
     setFilter(filter: any[]): void;
     getFilter(): any[];
+    setProperty(name: string, value: any): void;
+    getProperty(name: string): any;
 }

src/ui-mapbox/layers/layer-factory.ios.ts

@@ -90,4 +90,17 @@ export class Layer implements LayerCommon {
     getFilter(): any[] {
         return FilterParser.toJson(this.instance.predicate);
     }
+
+    setProperty(name: string, value: any) {
+        const properties = PropertyParser.parsePropertiesForLayer({ [name]: value });
+        for (const propKey in properties) {
+            if (Object.prototype.hasOwnProperty.call(properties, propKey)) {
+                this.instance[propKey] = properties[propKey];
+            }
+        }
+    }
+
+    getProperty(name: string): any {
+        return PropertyParser.propertyValueFromLayer(this.instance, name);
+    }
 }

src/ui-mapbox/layers/parser/property-parser.android.ts

@@ -4,6 +4,10 @@ function toCamelCase(s) {
     return s.replace(/([-_][a-z])/gi, ($1) => $1.toUpperCase().replace('-', '').replace('_', ''));
 }
 
+function toPascalCase(s) {
+    return s.replace(/(^[a-z]|[-_][a-z])/gi, ($1) => $1.toUpperCase().replace('-', '').replace('_', ''));
+}
+
 const Expression = com.mapbox.mapboxsdk.style.expressions.Expression;
 function transformValue(key, value) {
     let nValue = value;
@@ -36,4 +40,28 @@ export class PropertyParser {
 
         return nProperties;
     }
+
+    static propertyValueFromLayer(layer, key: string): any {
+        const getterMethodName = `get${toPascalCase(key)}`;
+
+        let nValue: com.mapbox.mapboxsdk.style.layers.PropertyValue<any>;
+        try {
+            nValue = layer[getterMethodName]();
+        } catch (e) {
+            // native method seems not exist
+            return null;
+        }
+
+        if (!nValue || nValue.isNull()) {
+            return null;
+        }
+
+        if (nValue.isExpression()) {
+            return JSON.parse(nValue.getExpression().toString());
+        } else if (!!nValue.getColorInt()) {
+            return new Color(nValue.getColorInt().intValue());
+        } else {
+            return nValue.getValue();
+        }
+    }
 }

src/ui-mapbox/layers/parser/property-parser.d.ts

@@ -1,3 +1,4 @@
 export declare class PropertyParser {
     static parsePropertiesForLayer(propertiesObject: any): any;
+    static propertyValueFromLayer(layer, key: string): any;
 }

src/ui-mapbox/layers/parser/property-parser.ios.ts

@@ -78,4 +78,27 @@ export class PropertyParser {
 
         return nProperties;
     }
+
+    static propertyValueFromLayer(layer, key: string): any {
+        const actualKey = keysMap[key] || toCamelCase(key);
+        const nValue: NSExpression = layer[actualKey];
+
+        if (!nValue) {
+            return null;
+        }
+
+        if (nValue.expressionType === NSExpressionType.ConstantValueExpressionType) {
+            if (nValue.constantValue instanceof UIColor) {
+                return Color.fromIosColor(nValue.constantValue);
+            } else {
+                return nValue.constantValue;
+            }
+        } else {
+            const expressionObj = (nValue as any).mgl_jsonExpressionObject;
+            const data = NSJSONSerialization.dataWithJSONObjectOptionsError(expressionObj, 0);
+            const expression: any = NSString.alloc().initWithDataEncoding(data, NSUTF8StringEncoding);
+
+            return JSON.parse(expression);
+        }
+    }
 }