GeoExt.data.PrintProvider

Extends

• Ext.util.Observable

class GeoExt.data.PrintProvider

Provides an interface to a Mapfish or GeoServer print module. For printing, one or more instances of GeoExt.data.PrintPage are also required to tell the PrintProvider about the scale and extent (and optionally rotation) of the page(s) we want to print.

Example Use

Minimal code to print as much of the current map extent as possible as soon as the print service capabilities are loaded, using the first layout reported by the print service:

var mapPanel = new GeoExt.MapPanel({
    renderTo: "mappanel",
    layers: [new OpenLayers.Layer.WMS("wms", "/geoserver/wms",
        {layers: "topp:tasmania_state_boundaries"})],
    center: [146.56, -41.56],
    zoom: 7
});
var printProvider = new GeoExt.data.PrintProvider({
    url: "/geoserver/pdf",
    listeners: {
        "loadcapabilities": function() {
            var printPage = new GeoExt.data.PrintPage({
                printProvider: printProvider
            });
            printPage.fit(mapPanel, true);
            printProvider.print(mapPanel, printPage);
        }
    }
});

Config Options

Configuration properties in addition to those listed for Ext.util.Observable.

autoLoad

Boolean If set to true, the capabilities will be loaded upon instance creation, and loadCapabilities does not need to be called manually. Setting this when capabilities and no url is provided has no effect. Default is false.

baseParams

Object Key-value pairs of base params to be add to every request to the service. Optional.

capabilities

Object Capabilities of the print service. Only required if url is not provided. This is the object returned by the info.json endpoint of the print service, and is usually obtained by including a script tag pointing to http://path/to/printservice/info.json?var=myvar in the head of the html document, making the capabilities accessible as window.myvar. This property should be used when no local print service or proxy is available, or when you do not listen for the loadcapabilities events before creating components that require the PrintProvider’s capabilities to be available.

encoding

String The encoding to set in the headers when requesting the print service. Prevent character encoding issues, especially when using IE. Default is retrieved from document charset or characterSet if existing or UTF-8 if not.

method

String Either POST or GET (case-sensitive). Method to use when sending print requests to the servlet. If the print service is at the same origin as the application (or accessible via proxy), then POST is recommended. Use GET when accessing a remote print service with no proxy available, but expect issues with character encoding and URLs exceeding the maximum length. Default is POST.

timeout

Number Timeout of the POST Ajax request used for the print request (in milliseconds). Default of 30 seconds. Has no effect if method is set to GET.

url

String Base url of the print service. Only required if capabilities is not provided. This is usually something like http://path/to/mapfish/print for Mapfish, and http://path/to/geoserver/pdf for GeoServer with the printing extension installed. This property requires that the print service is at the same origin as the application (or accessible via proxy).

Public Properties

Public properties in addition to those listed for Ext.util.Observable.

PrintProvider.customParams

Object Key-value pairs of custom data to be sent to the print service. Optional. This is e.g. useful for complex layout definitions on the server side that require additional parameters.

PrintProvider.dpi

Ext.data.Record the record for the currently used resolution. Read-only, use setDpi to set the value.

PrintProvider.dpis

Ext.data.JsonStore read-only. A store representing the dpis available.

Fields of records in this store:

• name - String the name of the dpi
• value - Float the dots per inch

PrintProvider.layout

Ext.data.Record the record of the currently used layout. Read-only, use setLayout to set the value.

PrintProvider.layouts

Ext.data.JsonStore read-only. A store representing the layouts available.

Fields of records in this store:

• name - String the name of the layout
• size - Object width and height of the map in points
• rotation - Boolean indicates if rotation is supported

PrintProvider.scales

Ext.data.JsonStore read-only. A store representing the scales available.

Fields of records in this store:

• name - String the name of the scale
• value - Float the scale denominator

Public Methods

Public methods in addition to those listed for Ext.util.Observable.

PrintProvider.loadCapabilities()

Loads the capabilities from the print service. If this instance is configured with either capabilities or a url and autoLoad set to true, then this method does not need to be called from the application.

PrintProvider.print()

Parameters:

• map – GeoExt.MapPanel or OpenLayers.Map The map to print.
• pages – Array of GeoExt.data.PrintPage or GeoExt.data.PrintPage page(s) to print.
• options – Object of additional options, see below.

Sends the print command to the print service and opens a new window with the resulting PDF.

Valid properties for the options argument:

• legend - GeoExt.LegendPanel If provided, the legend will be added to the print document. For the printed result to look like the LegendPanel, the following !legends block should be included in the items of your page layout in the print module’s configuration file:

  - !legends
      maxIconWidth: 0
      maxIconHeight: 0
      classIndentation: 0
      layerSpace: 5
      layerFontSize: 10
  

• overview - OpenLayers.Control.OverviewMap If provided, the layers for the overview map in the printout will be taken from the OverviewMap control. If not provided, the print service will use the main map’s layers for the overview map. Applies only for layouts configured to print an overview map.

PrintProvider.setDpi()

Parameter:dpi – Ext.data.Record the dpi record.

Sets the dpi for this printProvider.

PrintProvider.setLayout()

Parameter:layout – Ext.data.Record the record of the layout.

Sets the layout for this printProvider.

Events

Events in addition to those listed for Ext.util.Observable.

beforeencodelayer

Triggered before a layer is encoded. This can be used to exclude layers from the printing, by having the listener return false.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• layer - OpenLayers.Layer the layer which is about to be encoded.

beforeprint

Triggered when the print method is called. TODO: rename this event to beforeencode

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• map - OpenLayers.Map the map being printed
• pages - Array of GeoExt.data.PrintPage the print pages being printed
• options - Object the options to the print command

dpichange

Triggered when the dpi value is changed.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• dpi - Ext.data.Record the new dpi record

encodelayer

Triggered when a layer is encoded. This can be used to modify the encoded low-level layer object that will be sent to the print service.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• layer - OpenLayers.Layer the layer which is about to be encoded.
• encodedLayer - Object the encoded layer that will be sent to the print service.

layoutchange

Triggered when the layout is changed.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• layout - Ext.data.Record the new layout

loadcapabilities

Triggered when the capabilities have finished loading. This event will only fire when capabilities is not configured.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• capabilities - Object the capabilities

print

Triggered when the print document is opened.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• url - String the url of the print document

printexception

Triggered when using the POST method, when the print backend returns an exception.

Listener arguments:

• printProvider - GeoExt.data.PrintProvider this PrintProvider
• response - Object the response object of the XHR