Class: ImageTile

Extends

• Tile

Methods

dispatchEvent(event){boolean | undefined} inherited

events/Target.js, line 85

Dispatches an event and calls all listeners listening for events of this type. The event parameter can either be a string or an Object with a type property.

Name	Type	Description
event	BaseEvent | string	Event object.

Returns:

false if anyone called preventDefault on the event object or if any of the listeners returned false.

getImage(){HTMLCanvasElement | HTMLImageElement | HTMLVideoElement}

ImageTile.js, line 64

Get the HTML image element for this tile (may be a Canvas, Image, or Video).

Returns:

Image.

getTileCoord(){TileCoord} inherited

Tile.js, line 233

Get the tile coordinate for this tile.

Returns:

The tile coordinate.

load()

ImageTile.js, line 144

Load the image or retry if loading previously failed. Loading is taken care of by the tile queue, and calling this method is only needed for preloading or for reloading in case of an error.

To retry loading tiles on failed requests, use a custom tileLoadFunction that checks for error status codes and reloads only when the status code is 408, 429, 500, 502, 503 and 504, and only when not too many retries have been made already:

const retryCodes = [408, 429, 500, 502, 503, 504];
const retries = {};
source.setTileLoadFunction((tile, src) => {
  const image = tile.getImage();
  fetch(src)
    .then((response) => {
      if (retryCodes.includes(response.status)) {
        retries[src] = (retries[src] || 0) + 1;
        if (retries[src] <= 3) {
          setTimeout(() => tile.load(), retries[src] * 1000);
        }
        return Promise.reject();
      }
      return response.blob();
    })
    .then((blob) => {
      const imageUrl = URL.createObjectURL(blob);
      image.src = imageUrl;
      setTimeout(() => URL.revokeObjectURL(imageUrl), 5000);
    })
    .catch(() => tile.setState(3)); // error
});

setState(state) inherited

Tile.js, line 252

Sets the state of this tile. If you write your own tileLoadFunction , it is important to set the state correctly to ERROR when the tile cannot be loaded. Otherwise the tile cannot be removed from the tile queue and will block other requests.

Name	Type	Description
state	ol/TileState	State.