Windows

The Layouts API is accessible through the io.layouts object.

It is possible to configure the Layouts library by using the layouts property of the optional Config object passed during the initialization of the io.Connect JavaScript library. The Layouts library supports several modes of initialization. It can also be configured whether to auto save the context of individual windows and for which Layout types (Global, App Default, Workspace) to save it.

Below is an example of configuring the Layouts library:

const config = {
    layouts: {
        mode: "full",
        // Individual window context will be saved only when saving the specified types of Layouts.
        autoSaveWindowContext: ["Global", "Workspace"]
    }
};

const io = await IODesktop(config);

The different modes of the Layouts library restrict or enable certain functionalities. In "slim" mode, Layouts can't be manipulated (created, removed, renamed) and Layout events aren't available, but custom context data can still be saved. In "full" mode, all functionalities are available.

The layouts object has the following properties:

Current Global Layout

To get the currently restored Global Layout, use the getCurrentLayout() method:

const currentLayout = await io.layouts.getCurrentLayout();

Listing All Layouts

To get a collection of all currently available Layout objects, use the list() method:

const layouts = io.layouts.list();

The list() method isn't available in "slim" mode. Use export() instead.

All Layouts by Type

To get all Layouts by type, use the getAll() method and pass a LayoutType. It returns a collection of LayoutSummary objects, which don't contain the extensive objects describing the actual Layout components:

const allGlobalLayouts = await io.layouts.getAll("Global");

Specific Layout

To get a specific Layout, use the get() method and provide the name of the Layout and the LayoutType as arguments. Returns the requested Layout object or undefined if a Layout with the specified name and type doesn't exist:

const name = "My Layout";
const type = "Global";

const myLayout = await io.layouts.get(name, type);

Save & Restore

To save a Layout, use the save() method and pass a NewLayoutOptions object with a required name property. If a Layout with that name already exists, it will be replaced. The method resolves with the saved Layout:

const options = {
    name: "My Layout"
};

const savedLayout = await io.layouts.save(options);

To restore a Layout, use the restore() method and pass a RestoreOptions object specifying the name of the Layout (required) and other restore options:

const restoreOptions = {
    name: "My Layout",
    // Specify whether to close all running apps before restoring the Layout.
    // The default is `true` for Global Layouts.
    closeRunningInstance: false
};

await io.layouts.restore(restoreOptions);

⚠️ Note that saving, and especially restoring, a Global Layout may be a taxing operation depending mainly on how many apps there are in the Layout, how heavy they are, and how much context is attached to the Layout. If you need a quicker way to switch between Global Layouts, see the Hibernate & Resume section.

Available since io.Connect Desktop 9.1

When saving a Layout, you can specify whether to set it as the currently active Global Layout by using the setAsCurrent property of the NewLayoutOptions object:

const options = {
    name: "My Layout",
    setAsCurrent: true
};

const myLayout = await io.layouts.save(options);

Hibernate & Resume

Hibernating and resuming provides a quicker way to save and restore Global Layouts. The hibernation operation saves the Layout (therefore the original Global Layout will be overwritten) and enables you to resume (restore) the Layout more quickly by preserving the participating app instances and hiding them from the user. If you have heavy apps in a Layout and they take a lot of time to load, you may choose to hibernate the Layout when the user switches to another Layout. Resuming the Layout later will save the time usually needed for loading the heavy apps, but at the expense of higher memory consumption on the user machine. You should carefully consider the advantages and disadvantages of using hibernation when deciding on a strategy for saving and restoring Global Layouts.

⚠️ Note that in order for the hibernation operation to be most beneficial, you should prevent your app instances from closing when being hibernated. You can specify settings for closing or preserving hibernated app instances globally and per app which provides you with flexibility when designing your hibernation strategy. For more details, see the Developers > Configuration > System > App Settings > Hibernation and Developers > Configuration > Application > Hibernation sections.

To hibernate a Layout, use the hibernate() method and provide the name of the Layout to hibernate as a required first argument. As a second optional argument, you can pass a HibernationOptions object:

const name = "My Layout";
const options = {
    context: { io: 42 },
    metadata: { layout: "MyHibernatedLayout"}
};

const result = await io.layouts.hibernate(name, options);

console.log(`Layout hibernated ${result.status === "Success" ? "successfully" : "unsuccessfully"}.`);

To resume a hibernated Layout, use the resume() method and provide the name of the Layout to resume as a required first argument. As optional second and third arguments you can provide context for the resumed Layout and a ResumeOptions object:

const name = "My Layout";
const context = { io: 42 };
const options = {
    // Will close any already running app instances before resuming the Layout.
    cleanUp: true
};

const result = await io.layouts.resume(name, context, options);

console.log(`Layout resumed ${result.status === "Success" ? "successfully" : "unsuccessfully"}.`);

Rename

To rename a Layout, use the rename() method. You must pass the Layout object to rename as a first argument and the new name for the Layout as a second argument:

await io.layouts.rename(myLayout, "My New Layout");

Remove

To remove a Layout, use the remove() method. You must pass the LayoutType and the name of the Layout as arguments:

await io.layouts.remove("Global", "My Layout");

Export & Import

You can export all currently available Layout objects with the export() method. Exported Layouts can be stored to a database and then be used as restore points, or can be sent to another user and imported on their machine:

const layouts = await io.layouts.export();

The export() method (as opposed to list()) is available in all modes if you need to get a collection of all Layouts.

To import exported Layouts, use the import() method. Pass the collection of Layout objects to import and specify an ImportMode:

const mode = "merge";

await io.layouts.import(layouts, mode);

The ImportMode controls the import behavior. If set to "replace" (default), all existing Layouts will be removed and will be replaced by the imported ones. If set to "merge", the imported Layouts will be added to the existing ones, replacing any of them with conflicting names.

Refresh

To force a refresh of the Layout list available to the user when using a REST service or io.Manager as a Layout store, use the forceRefresh() method:

await io.layouts.forceRefresh();

The Layouts API allows your app to react to Layout events - adding, removing, updating or renaming a Layout. Use the returned unsubscribe function to stop receiving notifications about the respective event.

Added

To get notified when a Layout is added, use the onAdded() method:

io.layouts.onAdded(console.log);

Removed

To get notified when a Layout is removed, use the onRemoved() method:

io.layouts.onRemoved(console.log);

Changed

To get notified when a Layout is changed, use the onChanged() method:

io.layouts.onChanged(console.log);

Renamed

To get notified when a Layout is renamed, use the onRenamed() method:

io.layouts.onRenamed(console.log);

When a Layout is saved, apps can store context data in it. When the Layout is restored, the context data is also restored and returned to the apps. Context data can be saved in all Layout types.

⚠️ Note that saving large volumes of custom data as window context (e.g., thousands of lines of table data) can lead to significant delays when saving a Layout. A Layout usually contains several (in some cases - many) apps and/or Workspaces (which can also contain many apps) and if one or more of the apps saves large amounts of context data each time a Layout is saved, this will significantly slow down the saving process. The methods for saving custom context work best with smaller amounts of data. If your app needs to save large amounts of data, you have to think about how to design this process better - for instance, you may store IDs, indices, etc., as context data, save the actual data to a database and when you restore the Layout, fetch the data using the data IDs saved as window context.

Saving Context Data

To save context data, apps can subscribe for Layout save requests using the onSaveRequested() method. A Layout save request event is fired when the user attempts to save a Layout or close a window, Workspace, etc. The on onSaveRequested() method accepts a callback which will be invoked when a Layout save request is triggered. The callback will receive as an argument a SaveRequestContext object containing the Layout name, type and context. Use it to determine the type of the Layout and instruct your app to react accordingly:

const saveRequestHandler = (requestInfo) => {
    // Get the Layout type.
    const layoutType = requestInfo.layoutType;

    // Return different context data depending on the Layout type.
    if (layoutType === "ApplicationDefault") {
        return { windowContext: { gridWidth: 42 } };

    } else if (layoutType === "Global") {
        return { windowContext: { gridWidth: 420 } };

    } else {
        // Return if not interested in other Layout types.
        return;
    };
};

io.layouts.onSaveRequested(saveRequestHandler);

The callback must return a SaveRequestResponse object that has a windowContext property.

After the Layout has been restored, the saved context data will be available in the window context:

// Extracting previously saved data from the window context.
const windowContext = await io.windows.my().getContext();
const gridWidth = windowContext.gridWidth;

Updating App Default Context

To manually update the context of the current window in its App Default Layout, use the updateDefaultContext() method:

const context = { io: 42 };

await io.layouts.updateDefaultContext(context);

Updating Context of Apps in Global Layouts

To update the context that will be saved for the current app in the currently loaded Global Layout, use the updateAppContextInCurrent() method. This method allows you to update the saved context for the current app in the Layout without having to save the entire Layout:

const context = { io: 42 };

await io.layouts.updateAppContextInCurrent(context);

io.Connect Desktop allows you to specify a default Global Layout that will be automatically loaded on start. You can get, set and clear the default Global Layout programmatically.

To get the current default Global Layout, use the getDefaultGlobal() method:

// May return `undefined` if no default Global Layout has been set.
const defaultLayout = await io.layouts.getDefaultGlobal();

To set a default Global Layout, use the setDefaultGlobal() method:

io.layouts.setDefaultGlobal("My Layout");

To clear the default Global Layout, use the clearDefaultGlobal() method:

io.layouts.clearDefaultGlobal();

For a complete list of the available Layouts API methods and properties, see the Layouts API Reference Documentation.