Gestire gli eventi del mouse

Seleziona la piattaforma: Android iOS JavaScript

Fai in modo che le funzionalità dei dati rispondano agli eventi mousemove e click e utilizzali per modificare l'aspetto di una funzionalità in base all'interazione dell'utente.

Attivare gli eventi del livello del set di dati

Segui questi passaggi per attivare gli eventi su un livello del set di dati:

  1. Registra un livello del set di dati per le notifiche di un evento chiamando la funzione addListener() sul livello del set di dati per ogni evento che vuoi registrare. In questo esempio, anche la mappa riceve un listener.

    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;
        }
    });

    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;
        }
    });

  2. Aggiungi il codice del gestore di eventi per applicare lo stile alla funzionalità selezionata in base al tipo di interazione.

    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;
    }

    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;
    }

  3. Utilizza una funzione di stile delle funzionalità per applicare gli stili. La funzione di stile delle funzionalità mostrata qui applica lo stile in modo condizionale in base al tipo di interazione. Qui sono definiti tre stili: uno per rendere il bordo in grassetto su mousemove, uno per modificare lo sfondo su click e uno stile predefinito.

    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;
    }

    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;
    }

Codice di esempio completo

TypeScript

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();

JavaScript

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();