Introduce background shorthand property (#5053)

* Introduce background shorthand style property

* Add text property in parser for BackgroundPosition value

reason: prevent parsing of background position (pass it as sample string)

* Introduce background-shorthand test page

* Modify parser unit tests to respect the new BackgroundPosition 'text' property

tns-core-modules/ui/core/view/view-common.ts

@@ -254,6 +254,13 @@ export abstract class ViewCommon extends ViewBase implements ViewDefinition {
         this.style.color = value;
     }
 
+    get background(): string {
+        return this.style.background;
+    }
+    set background(value: string) {
+        this.style.background = value;
+    }
+
     get backgroundColor(): Color {
         return this.style.backgroundColor;
     }

tns-core-modules/ui/core/view/view.d.ts

@@ -163,6 +163,11 @@ export abstract class View extends ViewBase {
      */
     color: Color;
 
+    /**
+     * Gets or sets the background style property.
+     */
+    background: string;
+
     /**
      * Gets or sets the background color of the view.
      */

tns-core-modules/ui/styling/style-properties.d.ts

@@ -54,6 +54,7 @@ export function transformConverter(text: string): TransformFunctionsInfo;
 export const clipPathProperty: CssProperty<Style, string>;
 export const colorProperty: InheritedCssProperty<Style, Color>;
 
+export const backgroundProperty: ShorthandProperty<Style, string>;
 export const backgroundColorProperty: CssAnimationProperty<Style, Color>;
 export const backgroundImageProperty: CssProperty<Style, string>;
 export const backgroundRepeatProperty: CssProperty<Style, BackgroundRepeat>;

tns-core-modules/ui/styling/style-properties.ts

@@ -26,6 +26,8 @@ import {
     multiplyAffine2d,
 } from "../../matrix";
 
+import * as parser from "../../css/parser";
+
 export type LengthDipUnit = { readonly unit: "dip", readonly value: dip };
 export type LengthPxUnit = { readonly unit: "px", readonly value: px };
 export type LengthPercentUnit = { readonly unit: "%", readonly value: percent };
@@ -544,6 +546,15 @@ function convertTransformValue(property: string, stringValue: string)
 }
 
 // Background properties.
+const backgroundProperty = new ShorthandProperty<Style, string | Color>({
+    name: "background", cssName: "background",
+    getter: function (this: Style) {
+        return `${this.backgroundColor} ${this.backgroundImage} ${this.backgroundRepeat} ${this.backgroundPosition}`;
+    },
+    converter: convertToBackgrounds
+});
+backgroundProperty.register(Style);
+
 export const backgroundInternalProperty = new CssProperty<Style, Background>({
     name: "backgroundInternal",
     cssName: "_backgroundInternal",
@@ -603,6 +614,30 @@ export const backgroundPositionProperty = new CssProperty<Style, string>({
 });
 backgroundPositionProperty.register(Style);
 
+function convertToBackgrounds(this: void, value: string): [CssProperty<any, any>, any][] {
+    if (typeof value === "string") {
+        const backgrounds = parser.parseBackground(value).value;
+        const backgroundColor = backgrounds.color ? new Color(backgrounds.color) : unsetValue;
+        const backgroundImage = backgrounds.image || unsetValue;
+        const backgroundRepeat = backgrounds.repeat || unsetValue;
+        const backgroundPosition = backgrounds.position ? backgrounds.position.text : unsetValue;
+
+        return [
+            [backgroundColorProperty, backgroundColor],
+            [backgroundImageProperty, backgroundImage],
+            [backgroundRepeatProperty, backgroundRepeat],
+            [backgroundPositionProperty, backgroundPosition]
+        ];
+    } else {
+        return [
+            [backgroundColorProperty, unsetValue],
+            [backgroundImageProperty, unsetValue],
+            [backgroundRepeatProperty, unsetValue],
+            [backgroundPositionProperty, unsetValue]
+        ];
+    }
+}
+
 function parseBorderColor(value: string): { top: Color, right: Color, bottom: Color, left: Color } {
     let result: { top: Color, right: Color, bottom: Color, left: Color } = { top: undefined, right: undefined, bottom: undefined, left: undefined };
     if (value.indexOf("rgb") === 0) {

tns-core-modules/ui/styling/style/style.d.ts

@@ -62,7 +62,7 @@ export class Style extends Observable {
     public tintColor: Color;
     public placeholderColor: Color;
 
-    public background: string | Color;
+    public background: string;
     public backgroundColor: Color;
     public backgroundImage: string;
     public backgroundRepeat: BackgroundRepeat;

tns-core-modules/ui/styling/style/style.ts

@@ -35,7 +35,7 @@ export class Style extends Observable implements StyleDefinition {
     public tintColor: Color;
     public placeholderColor: Color;
 
-    public background: string | Color;
+    public background: string;
     public backgroundColor: Color;
     public backgroundImage: string;
     public backgroundRepeat: BackgroundRepeat;