پرونده توسعه بعدی Harmonyos: برنامه حاکم

import { window } from '@kit.ArkUI'; // Import window management APIs
import { deviceInfo } from '@kit.BasicServicesKit'; // Import device information APIs

// Ruler scale line definition
class RulerLine {
  index: number; // Index of the scale line
  height: number; // Height of the scale line

  constructor(index: number, height: number) {
    this.index = index; // Initialize index
    this.height = height; // Initialize height
  }

  // Display scale numbering
  showNumber(): string {
    return this.index % 10 === 0 ? `${Math.floor(this.index / 10)}` : ''; // Show number every 10 units
  }
}

// Custom text styling extension
@Extend(Text)
function fancy() {
  .fontColor("#019dfe") // Set font color
  .fontSize(20); // Set font size
}

// Main ruler component
@Entry
@Component
struct RulerComponent {
  @State maxRulerHeight: number = 0; // Maximum ruler height
  @State @Watch('onCellWidthChanged') cellWidthInPixels: number = 17.28; // Pixels per millimeter
  @State textWidth: number = 80; // Text label width
  @State rulerLines: RulerLine[] = []; // Array of scale lines
  @State leftOffsetX: number = -300; // Left offset position
  @State currentPositionX: number = -300; // Current X position
  @State @Watch('onContainerHeightChanged') containerHeight: number = 53; // Container height
  @State originalContainerHeight: number = 53; // Original container height
  @State @Watch('onCellWidthChanged') containerWidth: number = 0; // Container width

  // Handle cell width changes
  onCellWidthChanged() {
    this.maxRulerHeight = vp2px(this.containerWidth) / this.cellWidthInPixels / 10;
  }

  // Handle container height changes
  onContainerHeightChanged() {
    this.containerHeight = Math.max(this.containerHeight, 53); // Ensure minimum height
  }

  // Lifecycle: Component initialization
  aboutToAppear(): void {
    // Set landscape orientation
    window.getLastWindow(getContext()).then((windowClass) => {
      windowClass.setPreferredOrientation(window.Orientation.LANDSCAPE);
    });

    // Initialize scale lines
    for (let i = 0; i <= 15 * 10; i++) {
      const lineHeight: number = (i % 10 === 0) ? 90 : (i % 5 === 0) ? 60 : 45;
      this.rulerLines.push(new RulerLine(i, lineHeight));
    }
  }

  // UI construction
  build() {
    Column() {
      Stack() {
        // Scale lines rendering
        Stack() {
          ForEach(this.rulerLines, (line: RulerLine, index: number) => {
            Line()
              .width(1)
              .height(`${line.height}px`)
              .backgroundColor(Color.White)
              .margin({ left: `${this.cellWidthInPixels * index}px` });
            Text(line.showNumber())
              .fontColor(Color.White)
              .fontSize(18)
              .width(`${this.textWidth}px`)
              .height(`${this.textWidth}px`)
              .textAlign(TextAlign.Center)
              .margin({
                left: `${this.cellWidthInPixels * index - this.textWidth / 2}px`,
                top: `${line.height}px`
              });
          });
        }.width('100%').height('100%').align(Alignment.TopStart);

        // Control panel
        Column({ space: 15 }) {
          Text(`Current Device: ${deviceInfo.marketName}`).fancy();
          Counter() {
            Text(`Measurement: ${this.maxRulerHeight.toFixed(2)} cm`).fancy();
          }
          .foregroundColor(Color.White)
          .width(300)
          .onInc(() => {
            this.containerHeight = px2vp(vp2px(this.containerHeight) + this.cellWidthInPixels / 10;
          })
          .onDec(() => {
            this.containerHeight = px2vp(vp2px(this.containerHeight) - this.cellWidthInPixels / 10;
          });

          Counter() {
            Text(`mm Scale: ${this.cellWidthInPixels.toFixed(2)}px`).fancy();
          }
          .foregroundColor(Color.White)
          .width(300)
          .onInc(() => {
            this.cellWidthInPixels += 0.01;
          })
          .onDec(() => {
            this.cellWidthInPixels = Math.max(0.01, this.cellWidthInPixels - 0.01);
          });
        }

        // Interactive measurement area
        RelativeContainer() {
          Rect()
            .fill("#80019dfe")
            .borderColor("#019dfe")
            .borderWidth({ left: 1, right: 1 })
            .clip(true)
            .width("100%")
            .height("100%")
            .onAreaChange((oldArea: Area, newArea: Area) => {
              this.containerWidth = newArea.width as number;
            });

          // Left draggable handle
          Stack() {
            Circle({ height: 30, width: 30 })
              .fill("#019dfe")
              .stroke(Color.Transparent)
              .strokeWidth(3);
            Circle({ height: 40, width: 40 })
              .fill(Color.Transparent)
              .stroke("#019dfe")
              .strokeWidth(3);
          }
          .hitTestBehavior(HitTestMode.Block)
          .padding(20)
          .alignRules({
            center: { anchor: "__container__", align: VerticalAlign.Center },
            middle: { anchor: "__container__", align: HorizontalAlign.Start }
          })
          .gesture(PanGesture({
            fingers: 1,
            direction: PanDirection.Horizontal,
            distance: 1
          }).onActionUpdate((event: GestureEvent) => {
            this.leftOffsetX = this.currentPositionX + event.offsetX / 2;
            this.containerHeight = this.originalContainerHeight - event.offsetX;
          }).onActionEnd(() => {
            this.currentPositionX = this.leftOffsetX;
            this.originalContainerHeight = this.containerHeight;
          }));

          // Right draggable handle
          Stack() {
            Circle({ height: 30, width: 30 })
              .fill("#019dfe")
              .stroke(Color.Transparent)
              .strokeWidth(3);
            Circle({ height: 40, width: 40 })
              .fill(Color.Transparent)
              .stroke("#019dfe")
              .strokeWidth(3);
          }
          .hitTestBehavior(HitTestMode.Block)
          .padding(20)
          .alignRules({
            center: { anchor: "__container__", align: VerticalAlign.Center },
            middle: { anchor: "__container__", align: HorizontalAlign.End }
          })
          .gesture(PanGesture({
            fingers: 1,
            direction: PanDirection.Horizontal,
            distance: 1
          }).onActionUpdate((event: GestureEvent) => {
            this.leftOffsetX = this.currentPositionX + event.offsetX / 2;
            this.containerHeight = this.originalContainerHeight + event.offsetX;
          }).onActionEnd(() => {
            this.currentPositionX = this.leftOffsetX;
            this.originalContainerHeight = this.containerHeight;
          }));
        }
        .width(this.containerHeight)
        .height("100%")
        .translate({ x: this.leftOffsetX })
        .gesture(PanGesture({
          fingers: 1,
          direction: PanDirection.Horizontal,
          distance: 1
        }).onActionUpdate((event: GestureEvent) => {
          if (event) {
            this.leftOffsetX = this.currentPositionX + event.offsetX;
          }
        }).onActionEnd(() => {
          this.currentPositionX = this.leftOffsetX;
        }));
      }
    }.height('100%').width('100%')
    .padding({ left: 30, right: 10 })
    .backgroundColor("#181b22");
  }
}