Gestire gli eventi del mouse

Seleziona la piattaforma: Android iOS JavaScript

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

Attiva gli eventi del livello del set di dati

Per attivare gli eventi in un livello del set di dati:

1. Registra un livello del set di dati per le notifiche degli eventi chiamando la funzione addListener() sul livello del set di dati per ogni evento da registrare. In questo esempio la mappa riceve anche un ascoltatore.

   TypeScriptJavaScript
   datasetLayer = map.getDatasetFeatureLayer(datasetId);
   datasetLayer.style = applyStyle;
   
   datasetLayer.addListener('click', handleClick);
   datasetLayer.addListener('mousemove', handleMouseMove);
   
   // Map event listener.
   map.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

   Nota: leggi la guida sull'utilizzo di TypeScript e Google Maps.
   datasetLayer = map.getDatasetFeatureLayer(datasetId);
   datasetLayer.style = applyStyle;
   datasetLayer.addListener("click", handleClick);
   datasetLayer.addListener("mousemove", handleMouseMove);
   // Map event listener.
   map.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. Aggiungi il codice del gestore degli eventi per applicare uno stile alla funzionalità selezionata in base al tipo di interaction.

   TypeScriptJavaScript
   // Note, 'globalid' is an attribute in this Dataset.
   function handleClick(/* MouseEvent */ e) {
     if (e.features) {
       lastClickedFeatureIds =
           e.features.map((f) => f.datasetAttributes['globalid']);
     }
     //@ts-ignore
     datasetLayer.style = applyStyle;
   }
   
   function handleMouseMove(/* MouseEvent */ e) {
     if (e.features) {
       lastInteractedFeatureIds =
           e.features.map((f) => f.datasetAttributes['globalid']);
     }
     //@ts-ignore
     datasetLayer.style = applyStyle;
   }
   index.ts

   Nota: leggi la guida sull'utilizzo di TypeScript e Google Maps.
   // Note, 'globalid' is an attribute in this Dataset.
   function handleClick(/* MouseEvent */ e) {
     if (e.features) {
       lastClickedFeatureIds = e.features.map(
         (f) => f.datasetAttributes["globalid"],
       );
     }
   
     //@ts-ignore
     datasetLayer.style = applyStyle;
   }
   
   function handleMouseMove(/* MouseEvent */ e) {
     if (e.features) {
       lastInteractedFeatureIds = e.features.map(
         (f) => f.datasetAttributes["globalid"],
       );
     }
   
     //@ts-ignore
     datasetLayer.style = applyStyle;
   }
   index.js

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

   TypeScriptJavaScript
   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(/* FeatureStyleFunctionOptions */ params) {
     const datasetFeature = params.feature;
     // Note, 'globalid' is an attribute in this dataset.
     //@ts-ignore
     if (lastClickedFeatureIds.includes(datasetFeature.datasetAttributes['globalid'])) {
       return styleClicked;
     }
     //@ts-ignore
     if (lastInteractedFeatureIds.includes(datasetFeature.datasetAttributes['globalid'])) {
       return styleMouseMove;
     }
     return styleDefault;
   }
   index.ts

   Nota: leggi la guida sull'utilizzo di TypeScript e Google Maps.
   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(/* FeatureStyleFunctionOptions */ params) {
     const datasetFeature = params.feature;
   
     // Note, 'globalid' is an attribute in this dataset.
     //@ts-ignore
     if (
       lastClickedFeatureIds.includes(datasetFeature.datasetAttributes["globalid"])
     ) {
       return styleClicked;
     }
   
     //@ts-ignore
     if (
       lastInteractedFeatureIds.includes(
         datasetFeature.datasetAttributes["globalid"],
       )
     ) {
       return styleMouseMove;
     }
     return styleDefault;
   }
   index.js

Codice di esempio completo

TypeScriptJavaScript

let map: google.maps.Map;
let lastInteractedFeatureIds = [];
let lastClickedFeatureIds = [];
let datasetLayer;

// Note, 'globalid' is an attribute in this Dataset.
function handleClick(/* MouseEvent */ e) {
  if (e.features) {
    lastClickedFeatureIds =
        e.features.map((f) => f.datasetAttributes['globalid']);
  }
  //@ts-ignore
  datasetLayer.style = applyStyle;
}

function handleMouseMove(/* MouseEvent */ e) {
  if (e.features) {
    lastInteractedFeatureIds =
        e.features.map((f) => f.datasetAttributes['globalid']);
  }
  //@ts-ignore
  datasetLayer.style = applyStyle;
}

async function initMap() {
  // Request needed libraries.
  const { Map } = await google.maps.importLibrary('maps') as google.maps.MapsLibrary;

  const position = {lat: 40.780101, lng: -73.967780};
  map = new Map(document.getElementById('map') as HTMLElement, {
    zoom: 13,
    center: position,
    mapId: 'b98e588c46685dd7',
    mapTypeControl: false,
  });

  // Dataset ID for NYC park data.
  const datasetId = '6fe13aa9-b900-45e7-b636-3236672c3f4f';

  //@ts-ignore
  datasetLayer = map.getDatasetFeatureLayer(datasetId);
  datasetLayer.style = applyStyle;

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

  // Map event listener.
  map.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 attributionDiv = document.createElement('div');
  const attributionControl = createAttribution(map);

  attributionDiv.appendChild(attributionControl);
  map.controls[google.maps.ControlPosition.LEFT_BOTTOM].push(attributionDiv);
}

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(/* FeatureStyleFunctionOptions */ params) {
  const datasetFeature = params.feature;
  // Note, 'globalid' is an attribute in this dataset.
  //@ts-ignore
  if (lastClickedFeatureIds.includes(datasetFeature.datasetAttributes['globalid'])) {
    return styleClicked;
  }
  //@ts-ignore
  if (lastInteractedFeatureIds.includes(datasetFeature.datasetAttributes['globalid'])) {
    return styleMouseMove;
  }
  return styleDefault;
}

function createAttribution(map) {
  const attributionLabel = document.createElement('div');

  // Define CSS styles.
  attributionLabel.style.backgroundColor = '#fff';
  attributionLabel.style.opacity = '0.7';
  attributionLabel.style.fontFamily = 'Roboto,Arial,sans-serif';
  attributionLabel.style.fontSize = '10px';
  attributionLabel.style.padding = '2px';
  attributionLabel.style.margin = '2px';
  attributionLabel.textContent = 'Data source: NYC Open Data';
  return attributionLabel;
}

initMap();
index.ts

Nota: leggi la guida sull'utilizzo di TypeScript e Google Maps.

let map;
let lastInteractedFeatureIds = [];
let lastClickedFeatureIds = [];
let datasetLayer;

// Note, 'globalid' is an attribute in this Dataset.
function handleClick(/* MouseEvent */ e) {
  if (e.features) {
    lastClickedFeatureIds = e.features.map(
      (f) => f.datasetAttributes["globalid"],
    );
  }

  //@ts-ignore
  datasetLayer.style = applyStyle;
}

function handleMouseMove(/* MouseEvent */ e) {
  if (e.features) {
    lastInteractedFeatureIds = e.features.map(
      (f) => f.datasetAttributes["globalid"],
    );
  }

  //@ts-ignore
  datasetLayer.style = applyStyle;
}

async function initMap() {
  // Request needed libraries.
  const { Map } = await google.maps.importLibrary("maps");
  const position = { lat: 40.780101, lng: -73.96778 };

  map = new Map(document.getElementById("map"), {
    zoom: 13,
    center: position,
    mapId: "b98e588c46685dd7",
    mapTypeControl: false,
  });

  // Dataset ID for NYC park data.
  const datasetId = "6fe13aa9-b900-45e7-b636-3236672c3f4f";

  //@ts-ignore
  datasetLayer = map.getDatasetFeatureLayer(datasetId);
  datasetLayer.style = applyStyle;
  datasetLayer.addListener("click", handleClick);
  datasetLayer.addListener("mousemove", handleMouseMove);
  // Map event listener.
  map.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 attributionDiv = document.createElement("div");
  const attributionControl = createAttribution(map);

  attributionDiv.appendChild(attributionControl);
  map.controls[google.maps.ControlPosition.LEFT_BOTTOM].push(attributionDiv);
}

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(/* FeatureStyleFunctionOptions */ params) {
  const datasetFeature = params.feature;

  // Note, 'globalid' is an attribute in this dataset.
  //@ts-ignore
  if (
    lastClickedFeatureIds.includes(datasetFeature.datasetAttributes["globalid"])
  ) {
    return styleClicked;
  }

  //@ts-ignore
  if (
    lastInteractedFeatureIds.includes(
      datasetFeature.datasetAttributes["globalid"],
    )
  ) {
    return styleMouseMove;
  }
  return styleDefault;
}

function createAttribution(map) {
  const attributionLabel = document.createElement("div");

  // Define CSS styles.
  attributionLabel.style.backgroundColor = "#fff";
  attributionLabel.style.opacity = "0.7";
  attributionLabel.style.fontFamily = "Roboto,Arial,sans-serif";
  attributionLabel.style.fontSize = "10px";
  attributionLabel.style.padding = "2px";
  attributionLabel.style.margin = "2px";
  attributionLabel.textContent = "Data source: NYC Open Data";
  return attributionLabel;
}

initMap();
index.js