Toast

Version: 4.2

(quoted from Pop-up notification definition in Wikipedia)

The terms pop-up notification, toast, passive pop-up, snackbar, desktop notification, notification bubble, or simply notification all refer to a graphical control element that communicates certain events to the user without forcing them to react to this notification immediately, unlike conventional pop-up windows.

Desktop notifications usually disappear automatically after a short amount of time. Often their content is then stored in some widget that allows the users to access past notifications at a more convenient time.

Charba provides out of the box the feature to enable toast.

The toasting is native javascript implementation and Charba provides the wrapper in order to be able to use it.

info

The toast utility can be used even if the Charba.enable or DeferredCharba.enable are not called because it doesn't depend on CHART.JS.

You could show a toast simply using one of the following sample:

// shows a toast with default type and without title
Toaster.get().show("This is my toast content");
...
// shows a toast, multiple lines, with default type and without title
Toaster.get().show(Arrays.asList("This is my toast content (row 1)", "This is my toast content (row2)"));
...
// shows a toast with default type ERROR (red) and without title
Toaster.get().show(DefaultToastType.ERROR, "This is my toast content");
...
// shows a toast, multiple lines, with default type INFO (blue) and without title
Toaster.get().show(DefaultToastType.INFO, 
              Arrays.asList("This is my toast content (row 1)", "This is my toast content (row2)"));
...
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(DefaultToastType.ERROR);
// shows a toast with user options and without title
Toaster.get().show(options, "This is my toast content");
...
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(DefaultToastType.INFO);
// shows a toast, multiple lines, with user options and without title
Toaster.get().show(options, 
              Arrays.asList("This is my toast content (row 1)", "This is my toast content (row2)"));
...
// shows a toast with default type and title
Toaster.get().show("This is my toast title", "This is my toast content");
...
// shows a toast, multiple lines, with default type and title
Toaster.get().show("This is my toast title",
              Arrays.asList("This is my toast content (row 1)", "This is my toast content (row2)"));
...
// shows a toast with default type ERROR (red) and title
Toaster.get().show(DefaultToastType.ERROR, "This is my toast title", "This is my toast content");
...
// shows a toast, multiple lines, with default type ERROR (red) and title
Toaster.get().show(DefaultToastType.ERROR, "This is my toast title",
              Arrays.asList("This is my toast content (row 1)", "This is my toast content (row2)"));
...
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(DefaultToastType.ERROR);
// shows a toast with user options and title
Toaster.get().show(options, "This is my toast title", "This is my toast content");
...
Toaster.get().show(ToastOptions options, String title, List<String> label);
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(DefaultToastType.INFO);
// shows a toast with user options and title
Toaster.get().show(options, "This is my toast title",
              Arrays.asList("This is my toast content (row 1)", "This is my toast content (row2)"));

Both title and label can contain HTML code.

The show method is returning a status instance which report if the toast is showing, on queue, invalid or discard.

// shows a toast with default type and without title
Status status = Toaster.get().show("This is my toast content");
// checks status
if (Status.INVALID.equals(status) || Status.DISCARDED.equals(status)) {
  // the toast is not shown and will not
}

Context

When you show the context, you can pass a context, which is a map of objects, where you can store your objects in order to be them available in the handlers or actions.

The map is a key-value object.

// adds a dataset selection handler to a chart 
chart.addHandler(new DatasetSelectionEventHandler() {

    @Override
    public void onSelect(DatasetSelectionEvent event) {
        // creates toast context
        Map<String, Object> context = new HashMap<>();
        // stores the object in the context
        context.put("event", event);
        // creates toast options
        ToastOptions options = new ToastOptions();
        // adds close handler instance
        options.setCloseHandler(new CloseHandler() {
            
            @Override
            public void onClose(ToastItem item, ActionItem action) {
                DatasetSelectionEvent event = (DatasetSelectionEvent)item.getContext().get("event");
                // my logic
            }
        });
        // shows the toast
        Toaster.get().show(context, options, "This is my toast title", "This is my toast content"); 
    }
}, DatasetSelectionEvent.TYPE);

Options

The toast utility allows to define the properties that a toast could have to render the toast, by a toast options.

// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(DefaultToastType.INFO);
// sets progress bar type
options.setProgressBarType(DefaultProgressBarType.ERROR);
// sets icon
options.setIcon(ImagesHelper.toImg(Images.INSTANCE.fingerprintWhite()));
// shows toast
Status status = Toaster.get().show(options, "This is my toast title", "This is my toast content");

This is the structure and main components of a toast:

The following are the attributes that you can set:

Name	Type	Default	Description
actions	ActionItem[]	[]	Set the custom action to show in the toast. See actions section for details.
align	Align	Align.LEFT	Set the alignment of the toast actions.
autoHide	boolean	`true`	Set to `false` to avoid that the toast will disappear automatically. To close it, you must click on the toast.
borderRadius	int	8	The border radius of the toast element.
hideProgressBar	boolean	`false`	Set to `true` to hide the progress bar on the toast element.
hideShadow	boolean	`false`	Set to `true` to hide the shadow on the toast element.
icon	Img	`null`	To add an icon on the toast.
modifierKey	ModifierKey	`null`	Keyboard modifier key which must be pressed to enable the closure of the toast clicking on it.
progressBarHeight	int	3	The height of progress bar in pixels.
progressBarType	IsProgressBarType	DefaultProgressBarType.DEFAULT	The type of the progress bar to show on the toast element.
timeout	int	4000	The duration of toast, after that the toast will be hide automatically, according with `autoHide` option.
type	IsToastType	DefaultToastType.DEFAULT	The type of the toast.

Defaults

You can set default options to use for all toasts you want to show in your application, without replicating the same configuration on several part of the application, by the default toast options, accessible by the toaster.

// gets the default toast options  
DefaultToastOptions options = Toaster.get().getDefaults();
// sets type
options.setType(DefaultToastType.INFO);
// sets progress bar type
options.setProgressBarType(DefaultProgressBarType.ERROR);
// sets icon
options.setIcon(ImagesHelper.toImg(Images.INSTANCE.fingerprintWhite()));

Content

Based on the toast structure, you can set 3 different kinds of options to render the toast elements:

Title, which is a text, highlighted on the top of the toast
Label, which is a text, on the bottom of the toast
Action, which is a list of clickable elements, below the label.

Title

The toast title is a text which is located on the top of toast in order to provide a synthetic information about the toast.

// creates a toast options  
ToastOptions options = new ToastOptions();
// gets title
Title title = options.getTitle();
// sets color (overriding the toast type)
title.setColor(HtmlColor.BLACK);
// sets font
title.getFont().setSize(16);

The following are the attributes that you can set:

Name	Type	Default	Description
color	String - IsColor	#616161 -	Set the font color of title content. Setting it, you override the color that a toast type has been configured to use.
font	IsFont	see description	Font of text of title. The default font of the title has got the `weight` set to `Weight.BOLD` and the `size` to `15`. See Font.

Label

The toast label is a text which is located on the bottom of toast in order to provide the message to the user.

// creates a toast options  
ToastOptions options = new ToastOptions();
// gets label
Label label = options.getLabel();
// sets color (overriding the toast type)
label.setColor(HtmlColor.RED);
// sets font
label.getFont().setSize(12);

The following are the attributes that you can set:

Name	Type	Default	Description
color	String - IsColor	#616161 -	Set the font color of label content. Setting it, you override the color that a toast type has been configured to use.
font	IsFont	see description	Font of text of label. The default font of the title has got the `lineHeight` set to `20px` and the `size` to `14`. See Font.

Action

The toast action is a list of clickable elements which is located on the bottom of toast, below the label, in order to allow the user to perform specific actions from the toast.

// creates a toast options  
ToastOptions options = new ToastOptions();
// gets action
Action action = options.getAction();
// sets background color for all actions
action.setBackgroundColor(HtmlColor.RED);
// sets font
action.getFont().setSize(12);

The following are the attributes that you can set in order to apply the configured options to all actions:

Name	Type	Default	Description
backgroundColor	String - IsColor	HtmlColor.TRANSPARENT	Set the background color of the configured actions elements.
borderColor	String - IsColor	HtmlColor.TRANSPARENT	Set the border color of the configured actions elements.
borderRadius	int	0	Set the border radius of the configured actions elements.
borderStyle	BorderStyle	BorderStyle.NONE	Set the border style of the configured actions elements.
borderWidth	int	0	Set the border width of the configured actions elements.
color	String - IsColor	#616161 -	Set the font color of toast action element.
font	IsFont	see description	Font of text of toast action element. The default font of the actions have got the `lineHeight` set to `20px` and the `size` to `14`. See Font.

See actions section how you can set your toast actions and override the above options.

Type

Every toast has got own type, which will provide the information how to color the toast, both background and font color.

// DIRECTLY
// shows toast
Status status = Toaster.get().show(DefaultToastType.INFO, "This is my toast title", "This is my toast content");
...
// by OPTIONS
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(DefaultToastType.INFO);
// sets other options
...
// shows toast
Status status = Toaster.get().show(options, "This is my toast title", "This is my toast content");

There are some types provided out of the box, by the default type enumeration.

The following table shows the different colors for each default type.

Type	Background	Color
DEFAULT	HtmlColor.WHITE -	#616161 -
SUCCESS	#51C625 -	HtmlColor.WHITE -
WARNING	#DB9215 -	HtmlColor.WHITE -
ERROR	#DB2B1D -	HtmlColor.WHITE -
INFO	#27ABDB -	HtmlColor.WHITE -
DARK	HtmlColor.BLACK -	HtmlColor.WHITE -

Custom type

Where the default types are not enough and you want to use own colors for your toast, you can create your own type, by a toast type builder.

Here is the code to created it.

// creates my type
// passing own name, font and background colors
IsToastType myType = ToastTypeBuilder.create("myType", HtmlColor.BROWN, HtmlColor.ORANGE).build();
// shows toast
Status status = Toaster.get().show(myType, "This is my toast title", "This is my toast content");
...
// by OPTIONS
// creates my type
// passing own name, font and background colors
IsToastType myType = ToastTypeBuilder.create("myType", HtmlColor.BROWN, HtmlColor.ORANGE).build();
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets type
options.setType(myType);
// sets other options
...
// shows toast
Status status = Toaster.get().show(options, "This is my toast title", "This is my toast content");

A custom type can be created using Pattern or Gradient as background.

caution

The name of the type must follow the following rule, otherwise an exception will occur:

must start with a letter, [a-zA-Z]+
must contains whatever letter, number, underscore, hyphen, [_a-zA-Z0-9-]*

ProgressBar type

Every toast can have own progress bar in order to show to the user how much time is remaining before hiding the toast. A progress bar has got own type which will provide the information how to color the bar.

// creates a toast options  
ToastOptions options = new ToastOptions();
// sets progress bar type
options.setProgressBarType(DefaultProgressBarType.ERROR);
...
// shows toast
Toaster.get().show(options, "This is my toast title", "This is my toast content");

There are some progress bar types provided out of the box, by the default type enumeration.

The following table shows the different colors for each default type.

Type	Background
DEFAULT	HtmlColor.BLACK -
SUCCESS	#51C625 -
WARNING	#DB9215 -
ERROR	#DB2B1D -
INFO	#27ABDB -
RAINBOW	not color but a gradient:

Custom progress bar type

Where the default progress bar types are not enough and you want to use own colors for your bar, you can create your own type, by a toast progress bar type builder.

Here is the code to created it.

// creates my type
// passing own name and background colors
IsProgressBarType myType = ProgressBarTypeBuilder.create("myType", HtmlColor.ORANGE).build();
// creates a toast options  
ToastOptions options = new ToastOptions();
// sets my progress bar 
options.setProgressBarType(myType);
...
// shows toast
Toaster.get().show(options, "This is my toast title", "This is my toast content");

A custom progress bar type can be created using Gradient as background.

caution

The name of the type must follow the following rule, otherwise an exception will occur:

must start with a letter, [a-zA-Z]+
must contains whatever letter, number, underscore, hyphen, [_a-zA-Z0-9-]*

Actions

Actions make your toast interactive, letting the user take quick actions on your toast notification without interrupting their current workflow.

Actions appear in the expanded portion of your notification.

An action can be composed by the following items:

id, is an optional item, to have a unique name of the instance. If not set, an automatic id is calculated.
content, is an optional item, to set the content to show in the toast. If not set, the id is used as content.
handler, is an mandatory item, to set the callback to use when the action is clicked.

// creates my action with id and content
// when the action is clicked the toast is closed
ActionItem action = new ActionItem("Undo", "Undo", new ActionClickEventHandler() {

    /**
     * Invoked to manage CLICK events on toast action.
     * 
     * @param item toast item affected by event
     * @param event event fired on item
     * @return true if the toaster must be close after click on action
     */
    @Override
    public boolean onClick(ToastItem item, BaseNativeEvent newEvent) {
        // logic 
        return true;
    }
});
// sets bold to font
action.getFont().setWeight(Weight.BOLD);
// creates the options
ToastOptions options = new ToastOptions();
// sets actions
options.setActions(action);
// shows toast
Toaster.get().show(options, "This is my toast (with an action) content");

A action click handler must return a boolean in order to close the toast when action is clicked (returning true) or leave the toast to be close naturally at the end of timeout (returning false).

caution

The id of the action must follow the following rule, otherwise an exception will occur:

must start with a letter, [a-zA-Z]+
must contains whatever letter, number, underscore, hyphen, [_a-zA-Z0-9-]*

Options

Every single action can be configured in order to have a specific rendering on the user interface, overriding the common options defined in the action configuration element.

// creates my action with id and content
// when the action is clicked the toast is closed
ActionItem action = new ActionItem("Undo", "Undo", new ActionClickEventHandler() {

    /**
     * Invoked to manage CLICK events on toast action.
     * 
     * @param item toast item affected by event
     * @param event event fired on item
     * @return true if the toaster must be close after click on action
     */
    @Override
    public boolean onClick(ToastItem item, BaseNativeEvent newEvent) {
        // logic 
        return true;
    }
});
// sets bold to font
action.getFont().setWeight(Weight.BOLD);
// sets background color
action.setBackgroundColor("#C6C6C6");

The following table shows the different colors for each default type.

Name	Type	Default	Description
backgroundColor	String - IsColor	HtmlColor.TRANSPARENT	Set the background color of the configured action element.
borderColor	String - IsColor	HtmlColor.TRANSPARENT	Set the border color of the configured action element.
borderRadius	int	0	Set the border radius of the configured action element.
borderStyle	BorderStyle	BorderStyle.NONE	Set the border style of the configured action element.
borderWidth	int	0	Set the border width of the configured action element.
color	String - IsColor	#616161 -	Set the font color of toast action element.
font	IsFont	see description	Font of text of toast action element. The default font of the actions have got the `lineHeight` set to `20px` and the `size` to `14`. See Font.

Handlers

The toast utility provides the capabilities to listen when some status or actions are changed on the toast instance.

The status or actions are:

Open toast, when the toast is open, the handler is engaged
Click event, when a click event is fired on the toast, the handler is engaged
Close toast, when the toast is close, the handler is engaged

Open handler

The open handler is triggered when a toast is open and shown on the user interface.

// creates a toast options  
ToastOptions options = new ToastOptions();
...
// sets open handler
options.setOpenHandler(new OpenHandler(){

    /**
     * Invoked to be notified of toast item opening.
     * 
     * @param item toast item affected
     */
    public void onOpen(ToastItem item) {
       // my logic
    }
});
...
// shows toast
Toaster.get().show(options, "This is my toast title", "This is my toast content");

The handler provides a toast item which contains all options of the toast and additional information related to the runtime context where the toast is shown. See here the toast item details.

Close handler

The close handler is triggered when a toast is close and removed from the user interface.

// creates a toast options  
ToastOptions options = new ToastOptions();
...
// sets close handler
options.setCloseHandler(new CloseHandler(){

    /**
     * Invoked to be notified of toast item closing.
     * 
     * @param item toast item affected
     * @param action action which closed the toast or null if the toast has been closed naturally.
     */
    public onClose(ToastItem item, ActionItem action);
       // my logic
    }
});
...
// shows toast
Toaster.get().show(options, "This is my toast title", "This is my toast content");

The handler provides a toast item which contains all options of the toast and additional information related to the runtime context where the toast was shown and the action item, the toast has been closed clicking on a actioin.

See here the toast item details.
See here the action item details.

Click event handler

The click event handler is triggered when a click event is fired on the shown toast in the user interface.

// creates a toast options  
ToastOptions options = new ToastOptions();
...
// sets click event handler
options.setClickEventHandler(new ClickEventHandler(){

    /**
     * Invoked to manage CLICK events on toast item.
     * 
     * @param item toast item affected by event
     * @param event event fired on item
     */
    void onClick(ToastItem item, BaseNativeEvent event){
       // my logic
    }
});
...
// shows toast
Toaster.get().show(options, "This is my toast title", "This is my toast content");

The handler provides a toast item which contains all options of the toast and additional information related to the runtime context where the toast was shown and the event fired on the toast. See here the toast item details.

Maximum shown notifications

The toast utility provides the capability to limit the amount of toast you want to show in the user interface, at the same time.

This is because many toasts could waste the user interface making it chaotic.

You can decide how to manage new message to show when the maximum amount of open toasts is already reached, by the 2 policies, enumerated by maximum open items policy.

MaximumOpenItemsPolicy.QUEUE, as default, when new message is requested to be shown, the message is put in a queue and when the open items will be close, it will show.
MaximumOpenItemsPolicy.DISCARD, when new message is requested to be shown, the message is discard and never shown.

// sets "queue" policy (default)
Toaster.get().setMaxOpenItemsPolicy(MaximumOpenItemsPolicy.QUEUE);
...
// sets "discard" policy
Toaster.get().setMaxOpenItemsPolicy(MaximumOpenItemsPolicy.DISCARD);

By default, the maximum amount of open toast is 100 and you can not increment it. But you can decrease this value, by the toaster. And the minimum amount is 1 because at least 1 toast must be shown.

// reduces the amount of open toasts
// in this case, 4 messages
Toaster.get().setMaxOpenItems(4);
// resets to the default (100)
Toaster.get().setMaxOpenItems(Toaster.MAXIMUM_OPEN_ITEMS);

When new message is requested to be shown but there are already the maximum amount of open items, new messages are put in a queue and show when open items will be closed.

History

The toast utility can store in a local history a certain amount of toast (in FIFO approach), shown during the application utilization, in order to provide to the user visibility on all notifications you received. By default, the history is not enabled but it can, setting the amount of messages you want to maintain, by the toaster.

// -------------------------
// ENABLE history
// -------------------------
// sets the amount of toast to maintain in the history
// in this case, 20 messages
Toaster.get().setMaxHistoryItems(20);
// -------------------------
// DISABLE history
// -------------------------
// sets the amount of toast to 0
Toaster.get().setMaxHistoryItems(0);

The toaster provides the list of toast items in the history in order to enable to create an own panel where to show all the toast items.

// gets the toast history
List<ToastItem> history = Toaster.get().getHistoryItems();

Toast item

The history provides a unmodifiable list of a toast item.

A toast item contains all the options of a toast options and in addition the following ones, result of the context where the toast has been shows.

Name	Type	Description
context	Map<String,Object>	The context of the toast invocation, containing the meta data to consume by the configured handlers.
dateTime	java.util.Date	Every change status and action invocation is recorded with the date time when occurs. If the toast haven't recorded the passed status or the passed action, returns `null`
element	Div	The DOM element of the shown toast. Returns a consistent HTML element only when the toast is closed.
id	int	The unique id of the toast.
label	String	`null`
options	ToastItemOptions	The immutable options used to emit the toast.
status	Status	The last status of the toast.
title	String	`null`

The toast records when the status is changed and when an action has been invoked, clicking on that.

// gets date time when the toast was opened
Date whenOpened = toastItem.getDateTime(Status.OPENEND);
...
// creates the action
ActionItem action = new ActionItem("Undo", "Undo", new MyActionClickEventHandler());
... 
// gets date time when the "Undo" action has been performed.
// if not clicked, the result will be null.
Date whenClicked = toastItem.getDateTime(action);

Options builder

Charba provides a builder to create options using the set methods in sequence and get the toast options at the end of configuration, by build method.

// creates a simple toast options and shows it
ToastOptions options = ToastOptionsBuilder.create(DefaultProgressBarType.ERROR).build();

You can also use the builder to create toast with more configuration.

// creates a toast options  
ToastOptions options = ToastOptionsBuilder.create(DefaultToastType.INFO)
    .setProgressBarType(DefaultProgressBarType.ERROR)
    .setIcon(ImagesHelper.toImg(Images.INSTANCE.fingerprintWhite()))
    .setClickEventHandler(new ClickEventHandler(){
        void onClick(ToastItem item, BaseNativeEvent event){
           // my logic
        }
    })
    .build();
// shows toast
Toaster.get().show(options, "This is my toast title", "This is my toast content");

Toast​

Context​

Options​

Defaults​

Content​

Title​

Label​

Action​

Type​

Custom type​

ProgressBar type​

Custom progress bar type​

Actions​

Options​

Handlers​

Open handler​

Close handler​

Click event handler​

Maximum shown notifications​

History​

Toast item​

Options builder​

Toast

Context

Options

Defaults

Content

Title

Label

Action

Type

Custom type

ProgressBar type

Custom progress bar type

Actions

Options

Handlers

Open handler

Close handler

Click event handler

Maximum shown notifications

History

Toast item

Options builder