NativeScript/nativescript-core/ui/layouts/dock-layout/dock-layout.ios.ts

import { DockLayoutBase, View, layout } from "./dock-layout-common";

export * from "./dock-layout-common";

export class DockLayout extends DockLayoutBase {

    public onDockChanged(view: View, oldValue: "left" | "top" | "right" | "bottom", newValue: "left" | "top" | "right" | "bottom") {
        this.requestLayout();
    }

    public onMeasure(widthMeasureSpec: number, heightMeasureSpec: number): void {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        let measureWidth = 0;
        let measureHeight = 0;

        const width = layout.getMeasureSpecSize(widthMeasureSpec);
        const widthMode = layout.getMeasureSpecMode(widthMeasureSpec);

        const height = layout.getMeasureSpecSize(heightMeasureSpec);
        const heightMode = layout.getMeasureSpecMode(heightMeasureSpec);

        const horizontalPaddingsAndMargins = this.effectivePaddingLeft + this.effectivePaddingRight + this.effectiveBorderLeftWidth + this.effectiveBorderRightWidth;
        const verticalPaddingsAndMargins = this.effectivePaddingTop + this.effectivePaddingBottom + this.effectiveBorderTopWidth + this.effectiveBorderBottomWidth;

        let remainingWidth = widthMode === layout.UNSPECIFIED ? Number.MAX_VALUE : width - horizontalPaddingsAndMargins;
        let remainingHeight = heightMode === layout.UNSPECIFIED ? Number.MAX_VALUE : height - verticalPaddingsAndMargins;

        let tempHeight: number = 0;
        let tempWidth: number = 0;
        let childWidthMeasureSpec: number;
        let childHeightMeasureSpec: number;

        this.eachLayoutChild((child, last) => {
            if (this.stretchLastChild && last) {
                childWidthMeasureSpec = layout.makeMeasureSpec(remainingWidth, widthMode);
                childHeightMeasureSpec = layout.makeMeasureSpec(remainingHeight, heightMode);
            }
            else {
                // Measure children with AT_MOST even if our mode is EXACT
                childWidthMeasureSpec = layout.makeMeasureSpec(remainingWidth, widthMode === layout.EXACTLY ? layout.AT_MOST : widthMode);
                childHeightMeasureSpec = layout.makeMeasureSpec(remainingHeight, heightMode === layout.EXACTLY ? layout.AT_MOST : heightMode);
            }

            let childSize = View.measureChild(this, child, childWidthMeasureSpec, childHeightMeasureSpec);

            switch (child.dock) {
                case "top":
                case "bottom":
                    remainingHeight = Math.max(0, remainingHeight - childSize.measuredHeight);
                    tempHeight += childSize.measuredHeight;
                    measureWidth = Math.max(measureWidth, tempWidth + childSize.measuredWidth);
                    measureHeight = Math.max(measureHeight, tempHeight);
                    break;

                case "left":
                case "right":
                default:
                    remainingWidth = Math.max(0, remainingWidth - childSize.measuredWidth);
                    tempWidth += childSize.measuredWidth;
                    measureWidth = Math.max(measureWidth, tempWidth);
                    measureHeight = Math.max(measureHeight, tempHeight + childSize.measuredHeight);
                    break;
            }
        });

        measureWidth += horizontalPaddingsAndMargins;
        measureHeight += verticalPaddingsAndMargins;

        measureWidth = Math.max(measureWidth, this.effectiveMinWidth);
        measureHeight = Math.max(measureHeight, this.effectiveMinHeight);

        const widthAndState = View.resolveSizeAndState(measureWidth, width, widthMode, 0);
        const heightAndState = View.resolveSizeAndState(measureHeight, height, heightMode, 0);

        this.setMeasuredDimension(widthAndState, heightAndState);
    }

    public onLayout(left: number, top: number, right: number, bottom: number): void {
        super.onLayout(left, top, right, bottom);

        const insets = this.getSafeAreaInsets();
        const horizontalPaddingsAndMargins = this.effectivePaddingLeft + this.effectivePaddingRight + this.effectiveBorderLeftWidth + this.effectiveBorderRightWidth + insets.left + insets.right;
        const verticalPaddingsAndMargins = this.effectivePaddingTop + this.effectivePaddingBottom + this.effectiveBorderTopWidth + this.effectiveBorderBottomWidth + insets.top + insets.bottom;

        let childLeft = this.effectiveBorderLeftWidth + this.effectivePaddingLeft + insets.left;
        let childTop = this.effectiveBorderTopWidth + this.effectivePaddingTop + insets.top;

        let x = childLeft;
        let y = childTop;

        let remainingWidth = Math.max(0, right - left - horizontalPaddingsAndMargins);
        let remainingHeight = Math.max(0, bottom - top - verticalPaddingsAndMargins);

        this.eachLayoutChild((child, last) => {

            let childWidth = child.getMeasuredWidth() + child.effectiveMarginLeft + child.effectiveMarginRight;
            let childHeight = child.getMeasuredHeight() + child.effectiveMarginTop + child.effectiveMarginBottom;

            if (last && this.stretchLastChild) {
                // Last child with stretch - give it all the space and return;
                View.layoutChild(this, child, x, y, x + remainingWidth, y + remainingHeight);

                return;
            }

            let dock = DockLayout.getDock(child);
            switch (dock) {
                case "top":
                    childLeft = x;
                    childTop = y;
                    childWidth = remainingWidth;
                    y += childHeight;
                    remainingHeight = Math.max(0, remainingHeight - childHeight);
                    break;

                case "bottom":
                    childLeft = x;
                    childTop = y + remainingHeight - childHeight;
                    childWidth = remainingWidth;
                    remainingHeight = Math.max(0, remainingHeight - childHeight);
                    break;

                case "right":
                    childLeft = x + remainingWidth - childWidth;
                    childTop = y;
                    childHeight = remainingHeight;
                    remainingWidth = Math.max(0, remainingWidth - childWidth);
                    break;

                case "left":
                default:
                    childLeft = x;
                    childTop = y;
                    childHeight = remainingHeight;
                    x += childWidth;
                    remainingWidth = Math.max(0, remainingWidth - childWidth);
                    break;
            }

            View.layoutChild(this, child, childLeft, childTop, childLeft + childWidth, childTop + childHeight);
        });
    }
}