feat(list): add selected property to the list-item component

CHANGELOG.md

@@ -1,6 +1,11 @@
 # Ignite UI for Angular Change Log
 
 All notable changes for each version of this project will be documented in this file.
+## 19.1.1
+### New Features
+- IgxListItem
+  - Added a new `selected` input property, making it easier to indicate when a list item is selected by applying styling responsible for that state.
+
 ## 19.1.0
 ### General
 - `IgxCarousel`

package.json

@@ -74,7 +74,7 @@
     "@types/source-map": "0.5.2",
     "express": "^4.21.1",
     "fflate": "^0.8.1",
-    "igniteui-theming": "^15.0.0",
+    "igniteui-theming": "^15.1.1",
     "igniteui-trial-watermark": "^3.0.2",
     "lodash-es": "^4.17.21",
     "rxjs": "^7.8.0",

projects/igniteui-angular/package.json

@@ -73,7 +73,7 @@
         "tslib": "^2.3.0",
         "igniteui-trial-watermark": "^3.0.2",
         "lodash-es": "^4.17.21",
-        "igniteui-theming": "^15.0.0",
+        "igniteui-theming": "^15.1.1",
         "@igniteui/material-icons-extended": "^3.1.0"
     },
     "peerDependencies": {

projects/igniteui-angular/src/lib/core/styles/components/list/_list-component.scss

@@ -28,6 +28,11 @@
             @extend %igx-list-item-base--active !optional;
         }
 
+        // css class `igx-list__item-base--selected
+        @include e(item-base, $m: selected) {
+            @extend %igx-list-item-base--selected !optional;
+        }
+
         // css class 'igx-list__item-right' applied to the panning container shown when the list item is panned left
         @include e(item-right) {
             @extend %igx-list-item-pan !optional;

projects/igniteui-angular/src/lib/core/styles/components/list/_list-theme.scss

@@ -19,21 +19,27 @@
 /// @param {Color} $item-background [null] - The list item background color.
 /// @param {Color} $item-background-hover [null] - The list item hover background color.
 /// @param {Color} $item-background-active [null] - The active list item background color.
+/// @param {Color} $item-background-selected [null] - The selected list item background color.
 /// @param {Color} $item-text-color [null] - The list item text color.
 /// @param {Color} $item-text-color-hover [null] - The list item hover text color.
 /// @param {Color} $item-text-color-active [null] - The active list item text color.
+/// @param {Color} $item-text-color-selected [null] - The selected list item text color.
 /// @param {Color} $item-title-color [null] - The list item title color.
 /// @param {Color} $item-title-color-hover [null] - The list item hover title color.
 /// @param {Color} $item-title-color-active [null] - The active list item title color.
+/// @param {Color} $item-title-color-selected [null] - The selected list item title color.
 /// @param {Color} $item-subtitle-color [null] - The list item subtitle color.
 /// @param {Color} $item-subtitle-color-hover [null] - The list item hover subtitle color.
 /// @param {Color} $item-subtitle-color-active [null] - The active list item subtitle color.
+/// @param {Color} $item-subtitle-color-selected [null] - The selected list item subtitle color.
 /// @param {Color} $item-action-color [null] - The list item action color.
 /// @param {Color} $item-action-color-hover [null] - The list item hover action color.
 /// @param {Color} $item-action-color-active [null] - The active list item action color.
+/// @param {Color} $item-action-color-selected [null] - The selected list item action color.
 /// @param {Color} $item-thumbnail-color [null] - The list item thumbnail color.
 /// @param {Color} $item-thumbnail-color-hover [null] - The list item hover thumbnail color.
 /// @param {Color} $item-thumbnail-color-active [null] - The active list item thumbnail color.
+/// @param {Color} $item-thumbnail-color-selected [null] - The selected list item thumbnail color.
 /// @param {List} $border-radius [null] - The border radius used for list component.
 /// @param {List} $item-border-radius [null] - The border radius used for list item.
 /// @param {Color} $border-width [null] - The list border width.
@@ -54,21 +60,27 @@
     $item-background: null,
     $item-background-hover: null,
     $item-background-active: null,
+    $item-background-selected: null,
     $item-text-color: null,
     $item-text-color-hover: null,
     $item-text-color-active: null,
+    $item-text-color-selected: null,
     $item-title-color: null,
     $item-title-color-hover: null,
     $item-title-color-active: null,
+    $item-title-color-selected: null,
     $item-subtitle-color: null,
     $item-subtitle-color-hover: null,
     $item-subtitle-color-active: null,
+    $item-subtitle-color-selected: null,
     $item-action-color: null,
     $item-action-color-hover: null,
     $item-action-color-active: null,
+    $item-action-color-selected: null,
     $item-thumbnail-color: null,
     $item-thumbnail-color-hover: null,
     $item-thumbnail-color-active: null,
+    $item-thumbnail-color-selected: null,
     $border-color: null,
     $border-width: null,
 ) {
@@ -120,6 +132,16 @@
         }
     }
 
+    @if not($item-background-selected) and $item-background {
+        @if meta.type-of($item-background) == 'color' {
+            @if luminance($item-background) < .5 {
+                $item-background-selected: color.scale($item-background, $lightness: 8%);
+            } @else {
+                $item-background-selected: color.scale($item-background, $lightness: -8%);
+            }
+        }
+    }
+
     @if not($header-text-color) and $header-background {
         $header-text-color: text-contrast($header-background);
     }
@@ -180,28 +202,54 @@
         $item-text-color-active: text-contrast($item-background-active);
     }
 
+    @if not($item-text-color-selected) and $item-background-selected {
+        $item-text-color-selected: text-contrast($item-background-selected);
+    }
+
     @if not($item-title-color-active) and $item-background-active {
         $item-title-color-active: text-contrast($item-background-active);
     }
 
+    @if not($item-title-color-selected) and $item-background-selected {
+        $item-title-color-selected: text-contrast($item-background-selected);
+    }
+
     @if not($item-action-color-active) and $item-background-active {
         $item-action-color-active: text-contrast($item-background-active);
     }
 
+    @if not($item-action-color-selected) and $item-background-selected {
+        $item-action-color-selected: text-contrast($item-background-selected);
+    }
+
     @if not($item-thumbnail-color-active) and $item-background-active {
         $item-thumbnail-color-active: text-contrast($item-background-active);
     }
 
+    @if not($item-thumbnail-color-selected) and $item-background-selected {
+        $item-thumbnail-color-selected: text-contrast($item-background-selected);
+    }
+
     @if not($item-subtitle-color-active) and $item-background-active {
         @if meta.type-of($item-background-active) == 'color' {
             $item-subtitle-color-active: rgba(text-contrast($item-background-active), .74);
         }
     }
 
+    @if not($item-subtitle-color-selected) and $item-background-selected {
+        @if meta.type-of($item-background-selected) == 'color' {
+            $item-subtitle-color-selected: rgba(text-contrast($item-background-selected), .74);
+        }
+    }
+
     @if not($item-subtitle-color-active) and $item-text-color-active {
         $item-subtitle-color-active: $item-text-color-active;
     }
 
+    @if not($item-subtitle-color-selected) and $item-text-color-selected {
+        $item-subtitle-color-selected: $item-text-color-selected;
+    }
+
     @return extend($theme, (
         name: $name,
         border-radius: $border-radius,
@@ -212,21 +260,27 @@
         item-background: $item-background,
         item-background-hover: $item-background-hover,
         item-background-active: $item-background-active,
+        item-background-selected: $item-background-selected,
         item-text-color: $item-text-color,
         item-text-color-hover: $item-text-color-hover,
         item-text-color-active: $item-text-color-active,
+        item-text-color-selected: $item-text-color-selected,
         item-title-color:$item-title-color,
         item-title-color-hover:$item-title-color-hover,
         item-title-color-active:$item-title-color-active,
+        item-title-color-selected:$item-title-color-selected,
         item-subtitle-color: $item-subtitle-color,
         item-subtitle-color-hover: $item-subtitle-color-hover,
         item-subtitle-color-active: $item-subtitle-color-active,
+        item-subtitle-color-selected: $item-subtitle-color-selected,
         item-action-color: $item-action-color,
         item-action-color-hover: $item-action-color-hover,
         item-action-color-active: $item-action-color-active,
+        item-action-color-selected: $item-action-color-selected,
         item-thumbnail-color: $item-thumbnail-color,
         item-thumbnail-color-hover: $item-thumbnail-color-hover,
         item-thumbnail-color-active: $item-thumbnail-color-active,
+        item-thumbnail-color-selected: $item-thumbnail-color-selected,
         border-color: $border-color,
         border-width: $border-width,
         theme: map.get($schema, '_meta', 'theme'),
@@ -423,6 +477,12 @@
         }
     }
 
+    %igx-list-item-base--selected {
+        %igx-list-item-content {
+            @extend %igx-list-item-content--selected;
+        }
+    }
+
     %igx-list-item-pan {
         position: absolute;
         visibility: hidden;
@@ -550,6 +610,37 @@
         }
     }
 
+    %igx-list-item-content--selected {
+        color: var-get($theme, 'item-text-color-selected');
+        background: var-get($theme, 'item-background-selected');
+        z-index: 3;
+
+        %igx-list__item-line-title {
+            color: var-get($theme, 'item-title-color-selected')
+        }
+
+        %igx-list__item-line-subtitle {
+            color: var-get($theme, 'item-subtitle-color-selected')
+        }
+
+        %igx-list__item-actions {
+            color: var-get($theme, 'item-action-color-selected');
+
+            igx-icon,
+            igc-icon {
+                color: var-get($theme, 'item-action-color-selected')}
+        }
+
+        %igx-list__item-thumbnail {
+            color: var-get($theme, 'item-thumbnail-color-selected');
+
+            igx-icon,
+            igc-icon {
+                color: var-get($theme, 'item-thumbnail-color-selected')
+            }
+        }
+    }
+
     %igx-list-item-content--inactive {
         transition: transform .3s $out-quad;
     }

projects/igniteui-angular/src/lib/list/list-item.component.ts

@@ -133,6 +133,7 @@ export class IgxListItemComponent implements IListChild {
     private lastPanDir = IgxListPanState.NONE;
 
     private _role: string = '';
+    private _selected = false;;
 
     /**
      * Gets the `panState` of a `list item`.
@@ -281,6 +282,30 @@ export class IgxListItemComponent implements IListChild {
         this._role = val;
     }
 
+    /**
+     * Sets/gets whether the `list item` is selected.
+     * Selection is only applied to non-header items.
+     * When selected, the CSS class 'igx-list__item-base--selected' is added to the item.
+     * ```html
+     * <igx-list-item [selected]="true">Selected Item</igx-list-item>
+     * ```
+     * ```typescript
+     * let isSelected = this.listItem.selected;
+     * this.listItem.selected = true;
+     * ```
+     *
+     * @memberof IgxListItemComponent
+     */
+    @HostBinding('class.igx-list__item-base--selected')
+    @Input({ transform: booleanAttribute })
+    public get selected() {
+        return this._selected && !this.isHeader;
+    }
+
+    public set selected(value: boolean) {
+        this._selected = value;
+    }
+
     /**
      * Indicates whether `list item` should have header style.
      * ```typescript

projects/igniteui-angular/src/lib/list/list.component.spec.ts

@@ -24,7 +24,8 @@ import {
     ListWithIgxForAndScrollingComponent,
     TwoHeadersListComponent,
     TwoHeadersListNoPanningComponent,
-    ListDirectivesComponent
+    ListDirectivesComponent,
+    ListWithSelectedItemComponent
 } from '../test-utils/list-components.spec';
 import { configureTestSuite } from '../test-utils/configure-suite';
 import { wait } from '../test-utils/ui-interactions.spec';
@@ -44,7 +45,8 @@ describe('List', () => {
                 TwoHeadersListNoPanningComponent,
                 ListWithPanningTemplatesComponent,
                 ListWithIgxForAndScrollingComponent,
-                ListDirectivesComponent
+                ListDirectivesComponent,
+                ListWithSelectedItemComponent
             ]
         });
     });
@@ -661,6 +663,40 @@ describe('List', () => {
         }
     }));
 
+    it('should properly set and get the selected property of list items', () => {
+        const fixture = TestBed.createComponent(ListWithSelectedItemComponent);
+        const list = fixture.componentInstance.list;
+        fixture.detectChanges();
+
+        // Get all list items
+        const items = list.children.toArray();
+        const headerItem = items[0];
+        const firstItem = items[1];
+        const secondItem = items[2];
+
+        // Verify initial selected state
+        expect(headerItem.selected).toBe(false); // Headers should never be selected even if selected=true
+        expect(firstItem.selected).toBe(true);
+        expect(secondItem.selected).toBe(false);
+
+        // Check if the selected class is applied correctly
+        expect(headerItem.element.classList.contains('igx-list__item-base--selected')).toBe(false);
+        expect(firstItem.element.classList.contains('igx-list__item-base--selected')).toBe(true);
+        expect(secondItem.element.classList.contains('igx-list__item-base--selected')).toBe(false);
+
+        // Change selected state programmatically
+        secondItem.selected = true;
+        fixture.detectChanges();
+        expect(secondItem.selected).toBe(true);
+        expect(secondItem.element.classList.contains('igx-list__item-base--selected')).toBe(true);
+
+        // Try to select a header item (should not apply)
+        headerItem.selected = true;
+        fixture.detectChanges();
+        expect(headerItem.selected).toBe(false);
+        expect(headerItem.element.classList.contains('igx-list__item-base--selected')).toBe(false);
+    });
+
     it('Initializes igxListThumbnail directive', () => {
         const fixture = TestBed.createComponent(ListDirectivesComponent);
         fixture.detectChanges();

projects/igniteui-angular/src/lib/test-utils/list-components.spec.ts

@@ -63,6 +63,21 @@ export class BasicListComponent {
 export class ListWithHeaderComponent extends BasicListComponent {
 }
 
+@Component({
+    template: `
+    <div #wrapper>
+        <igx-list>
+            <igx-list-item selected [isHeader]="true">Header</igx-list-item>
+            <igx-list-item selected>Item 1</igx-list-item>
+            <igx-list-item>Item 2</igx-list-item>
+            <igx-list-item>Item 3</igx-list-item>
+        </igx-list>
+    </div>`,
+    imports: [IgxListComponent, IgxListItemComponent]
+})
+export class ListWithSelectedItemComponent extends BasicListComponent {
+}
+
 @Component({
     template: `
     <div #wrapper>