مدیریت رویدادهای موشواره

ویژگی‌های داده را طوری تنظیم کنید که به رویدادهای mousemove و click پاسخ دهند و از آن‌ها برای تغییر ظاهر ویژگی براساس تعامل کاربر استفاده کنید.

فعال کردن رویدادهای لایه مجموعه داده

برای فعال کردن رویدادها در لایه مجموعه داده، مراحل زیر را دنبال کنید:

1. با فراخوانی تابع addListener() در لایه مجموعه‌داده برای هر رویدادی که می‌خواهید ثبت کنید، لایه مجموعه‌داده را برای اعلان‌های رویداد ثبت کنید. در این مثال، نقشه نیز شنونده‌ای دریافت می‌کند.

   TypeScript

   datasetLayer = innerMap.getDatasetFeatureLayer(datasetId);
   datasetLayer.style = applyStyle;
   
   datasetLayer.addListener('click', handleClick);
   datasetLayer.addListener('mousemove', handleMouseMove);
   
   // Map event listener.
   innerMap.addListener('mousemove', () => {
       // If the map gets a mousemove, that means there are no feature layers
       // with listeners registered under the mouse, so we clear the last
       // interacted feature ids.
       if (lastInteractedFeatureIds?.length) {
           lastInteractedFeatureIds = [];
           datasetLayer.style = applyStyle;
       }
   });
   index.ts

   JavaScript

   datasetLayer = innerMap.getDatasetFeatureLayer(datasetId);
   datasetLayer.style = applyStyle;
   
   datasetLayer.addListener('click', handleClick);
   datasetLayer.addListener('mousemove', handleMouseMove);
   
   // Map event listener.
   innerMap.addListener('mousemove', () => {
       // If the map gets a mousemove, that means there are no feature layers
       // with listeners registered under the mouse, so we clear the last
       // interacted feature ids.
       if (lastInteractedFeatureIds?.length) {
           lastInteractedFeatureIds = [];
           datasetLayer.style = applyStyle;
       }
   });
   index.js

2. کد کنترل‌کننده رویداد را اضافه کنید تا عارضه انتخاب‌شده را براساس نوع تعامل سبک‌بندی کند.

   TypeScript

   // Note, 'globalid' is an attribute in this Dataset.
   function handleClick(event: google.maps.FeatureMouseEvent) {
       if (event.features) {
           lastClickedFeatureIds = event.features.map(
               (f) => (f as google.maps.DatasetFeature).datasetAttributes.globalid
           );
       }
       datasetLayer.style = applyStyle;
   }
   
   function handleMouseMove(event: google.maps.FeatureMouseEvent) {
       if (event.features) {
           lastInteractedFeatureIds = event.features.map(
               (f) => (f as google.maps.DatasetFeature).datasetAttributes.globalid
           );
       }
       datasetLayer.style = applyStyle;
   }
   index.ts

   JavaScript

   // Note, 'globalid' is an attribute in this Dataset.
   function handleClick(event) {
       if (event.features) {
           lastClickedFeatureIds = event.features.map(
               (f) => f.datasetAttributes.globalid
           );
       }
       datasetLayer.style = applyStyle;
   }
   
   function handleMouseMove(event) {
       if (event.features) {
           lastInteractedFeatureIds = event.features.map(
               (f) => f.datasetAttributes.globalid
           );
       }
       datasetLayer.style = applyStyle;
   }
   index.js

3. برای اعمال سبک‌ها، از تابع سبک عارضه استفاده کنید. تابع سبک ویژگی که در اینجا نشان داده شده است، سبک را به‌صورت شرطی براساس نوع تعامل اعمال می‌کند. سه سبک در اینجا تعریف شده است: یکی برای پررنگ کردن حاشیه در mousemove، یکی برای تغییر پس‌زمینه در click، و یک سبک پیش‌فرض.

   TypeScript

   const styleDefault = {
       strokeColor: 'green',
       strokeWeight: 2.0,
       strokeOpacity: 1.0,
       fillColor: 'green',
       fillOpacity: 0.3,
   };
   
   const styleClicked = {
       ...styleDefault,
       strokeColor: 'blue',
       fillColor: 'blue',
       fillOpacity: 0.5,
   };
   
   const styleMouseMove = {
       ...styleDefault,
       strokeWeight: 4.0,
   };
   
   function applyStyle(params: google.maps.FeatureStyleFunctionOptions) {
       const datasetFeature = params.feature;
   
       // Note, 'globalid' is an attribute in this dataset.
       if (
           lastClickedFeatureIds.includes(
               (datasetFeature as google.maps.DatasetFeature).datasetAttributes
                   .globalid
           )
       ) {
           return styleClicked;
       }
   
       if (
           lastInteractedFeatureIds.includes(
               (datasetFeature as google.maps.DatasetFeature).datasetAttributes
                   .globalid
           )
       ) {
           return styleMouseMove;
       }
       return styleDefault;
   }
   index.ts

   JavaScript

   const styleDefault = {
       strokeColor: 'green',
       strokeWeight: 2.0,
       strokeOpacity: 1.0,
       fillColor: 'green',
       fillOpacity: 0.3,
   };
   
   const styleClicked = {
       ...styleDefault,
       strokeColor: 'blue',
       fillColor: 'blue',
       fillOpacity: 0.5,
   };
   
   const styleMouseMove = {
       ...styleDefault,
       strokeWeight: 4.0,
   };
   
   function applyStyle(params) {
       const datasetFeature = params.feature;
   
       // Note, 'globalid' is an attribute in this dataset.
       if (
           lastClickedFeatureIds.includes(
               datasetFeature.datasetAttributes.globalid
           )
       ) {
           return styleClicked;
       }
   
       if (
           lastInteractedFeatureIds.includes(
               datasetFeature.datasetAttributes.globalid
           )
       ) {
           return styleMouseMove;
       }
       return styleDefault;
   }
   index.js

کد نمونه کامل

const mapElement = document.querySelector('gmp-map')!;
let innerMap: google.maps.Map;
let lastInteractedFeatureIds: string[] = [];
let lastClickedFeatureIds: string[] = [];
let datasetLayer: google.maps.FeatureLayer;

// Note, 'globalid' is an attribute in this Dataset.
function handleClick(event: google.maps.FeatureMouseEvent) {
    if (event.features) {
        lastClickedFeatureIds = event.features.map(
            (f) => (f as google.maps.DatasetFeature).datasetAttributes.globalid
        );
    }
    datasetLayer.style = applyStyle;
}

function handleMouseMove(event: google.maps.FeatureMouseEvent) {
    if (event.features) {
        lastInteractedFeatureIds = event.features.map(
            (f) => (f as google.maps.DatasetFeature).datasetAttributes.globalid
        );
    }
    datasetLayer.style = applyStyle;
}

async function init() {
    // Request needed libraries.
    await google.maps.importLibrary('maps');

    // Get the inner map.
    innerMap = mapElement.innerMap;

    // Dataset ID for NYC park data.
    const datasetId = 'a75dd002-ad20-4fe6-af60-27cd2ed636b4';

    datasetLayer = innerMap.getDatasetFeatureLayer(datasetId);
    datasetLayer.style = applyStyle;

    datasetLayer.addListener('click', handleClick);
    datasetLayer.addListener('mousemove', handleMouseMove);

    // Map event listener.
    innerMap.addListener('mousemove', () => {
        // If the map gets a mousemove, that means there are no feature layers
        // with listeners registered under the mouse, so we clear the last
        // interacted feature ids.
        if (lastInteractedFeatureIds?.length) {
            lastInteractedFeatureIds = [];
            datasetLayer.style = applyStyle;
        }
    });
}

const styleDefault = {
    strokeColor: 'green',
    strokeWeight: 2.0,
    strokeOpacity: 1.0,
    fillColor: 'green',
    fillOpacity: 0.3,
};

const styleClicked = {
    ...styleDefault,
    strokeColor: 'blue',
    fillColor: 'blue',
    fillOpacity: 0.5,
};

const styleMouseMove = {
    ...styleDefault,
    strokeWeight: 4.0,
};

function applyStyle(params: google.maps.FeatureStyleFunctionOptions) {
    const datasetFeature = params.feature;

    // Note, 'globalid' is an attribute in this dataset.
    if (
        lastClickedFeatureIds.includes(
            (datasetFeature as google.maps.DatasetFeature).datasetAttributes
                .globalid
        )
    ) {
        return styleClicked;
    }

    if (
        lastInteractedFeatureIds.includes(
            (datasetFeature as google.maps.DatasetFeature).datasetAttributes
                .globalid
        )
    ) {
        return styleMouseMove;
    }
    return styleDefault;
}

void init();
index.ts

const mapElement = document.querySelector('gmp-map');
let innerMap;
let lastInteractedFeatureIds = [];
let lastClickedFeatureIds = [];
let datasetLayer;

// Note, 'globalid' is an attribute in this Dataset.
function handleClick(event) {
    if (event.features) {
        lastClickedFeatureIds = event.features.map(
            (f) => f.datasetAttributes.globalid
        );
    }
    datasetLayer.style = applyStyle;
}

function handleMouseMove(event) {
    if (event.features) {
        lastInteractedFeatureIds = event.features.map(
            (f) => f.datasetAttributes.globalid
        );
    }
    datasetLayer.style = applyStyle;
}

async function init() {
    // Request needed libraries.
    await google.maps.importLibrary('maps');

    // Get the inner map.
    innerMap = mapElement.innerMap;

    // Dataset ID for NYC park data.
    const datasetId = 'a75dd002-ad20-4fe6-af60-27cd2ed636b4';

    datasetLayer = innerMap.getDatasetFeatureLayer(datasetId);
    datasetLayer.style = applyStyle;

    datasetLayer.addListener('click', handleClick);
    datasetLayer.addListener('mousemove', handleMouseMove);

    // Map event listener.
    innerMap.addListener('mousemove', () => {
        // If the map gets a mousemove, that means there are no feature layers
        // with listeners registered under the mouse, so we clear the last
        // interacted feature ids.
        if (lastInteractedFeatureIds?.length) {
            lastInteractedFeatureIds = [];
            datasetLayer.style = applyStyle;
        }
    });
}

const styleDefault = {
    strokeColor: 'green',
    strokeWeight: 2.0,
    strokeOpacity: 1.0,
    fillColor: 'green',
    fillOpacity: 0.3,
};

const styleClicked = {
    ...styleDefault,
    strokeColor: 'blue',
    fillColor: 'blue',
    fillOpacity: 0.5,
};

const styleMouseMove = {
    ...styleDefault,
    strokeWeight: 4.0,
};

function applyStyle(params) {
    const datasetFeature = params.feature;

    // Note, 'globalid' is an attribute in this dataset.
    if (
        lastClickedFeatureIds.includes(
            datasetFeature.datasetAttributes.globalid
        )
    ) {
        return styleClicked;
    }

    if (
        lastInteractedFeatureIds.includes(
            datasetFeature.datasetAttributes.globalid
        )
    ) {
        return styleMouseMove;
    }
    return styleDefault;
}

void init();
index.js