Objects

There are two ways to create an object on the screen:

• Uploading a pages.jsonl file onto the internal flash
• Use the jsonl command (via MQTT, serial or telnet console)

Cheatsheet

obj	Type	Description	Extra Parts
btn	Binary	Button
switch	Toggle	Switch	indicator, knob
checkbox	Toggle	Checkbox	indicator
label	Visual	Label
led	Visual	LED
spinner	Visual	Spinner	indicator
obj	Visual	Base Object
line	Visual	Line
img	Visual	Image
cpicker	Selector	Color picker	knob
roller	Selector	Roller	selected
dropdown	Selector	Dropdown List	selected, items, scrollbar
btnmatrix	Selector	Button Matrix	items
msgbox	Selector	Messagebox	items, items_bg
tabview	Selector	Tabview	items, items_bg, indicator, selected
tab	Selector	Tab
bar	Range	Progress Bar	indicator
slider	Range	Slider	indicator, knob
arc	Range	Arc	indicator, knob
linemeter	Range	Line Meter
gauge	Range	Gauge	indicator, ticks

Common Parameters

Common Properties

These are the common properties shared among all objects, but only the id and obj properties are required to create an object:

Property	Value	Default	Description
id	1..254	n/a	Required. ID of the object on this page. 0 for the page itself.
obj	string	n/a	Required. Name of the object type (see below)
page	0..12	n/a	ID of the page the object appears on (see below)
groupid	0..15	0 (none)	ID of the GPIO group the object belongs to
x	int16	0	Horizontal position on the page
y	int16	0	Vertical position on the page
w	int16	0	Width of the object
h	int16	0	Height of the object
enabled	bool	true	Object is touchable, if false, a disabled style is applied
hidden	bool	false	Object is hidden
opacity	uint8	255	How much the the object is opaque
swipe	bool	false	Page navigation using swipe gestures (see below)
action	string	0	Command handled locally (see below)
click	bool	true	Object is touch/clickable (also see enabled)
ext_click_h	uint8	0	Extended horizontal clickable are on the left and right
ext_click_v	uint8	0	Extended vertical clickable are on the top and bottom
parentid	uint8	0	Set the object to be the child of another object. x and y will be relative to the parent object. Property inheritance can affect the appearance of the of the children (more info in styling).
tag	JSONobject	n/a	Arbitrary attribute data. Once set, it will be included in each event message. For advanced scenarios (more info in an example).
jsonl	JSONobject	n/a	Pseudo-property to set multiple properties of an existing object in one go with a JSON object.

Tip

Further customizable properties can be found in styling.

Ids start from 1 on each page. You can have a maximum of 254 ids on each page. You don't have to use them in ascending order, you can for example use them for logical numbering (start labels from 11, 12, 13, buttons from 21, 22, 23 etc.)

Pages

If the page parameter is not present, the object is placed on the same page as the previous object. If page is not specified for the first object either, the current page being displayed is used.

"page":0 indicates that the object is visible on all pages. It can be used for example to specify a static menu bar. You can still hide the object on select pages if needed. Objects on page 0 appear on top of any objects on the underlying page.

Actions

Action commands are supported only by binary or visual type of objects and they are performed locally on the plate. The following actions can be set for these objects:

• p1 to p12 to switch to the corresponding page numbers directly
• prev to switch to the previous page
• next to switch to the next page
• back to go back to the home page

Check out the example for how to implement actions.
You can change the target pages using prev, back and next page attributes operation on the page objectpXb0.

Swipe

Objects and page area (p0bY) support swipe property. Enabling this will process left, right and down swipes on the object as next, prev and back page changes, respectively. The start of the swipe needs to be on the element which has this property enabled for the feature to activate.

Note

Page id p0b0 is not valid to set this property as it has to be set on real elements.

Events

All objects are touchable by default and respond to touch events. To disable touch events for an object set its enabled property to false. In this case the touch event "goes through" to the object on the layer below or to the page itself.

Events (and values) are published in a state topic corresponding to the object, eg. hasp/<nodename>/state/p1b2 with payload in json format eg. {"event":"up","val":1}.
Possible events (depending on object type) are:

Event	Description
down	Occurs when a button goes from depressed to pressed (the moment of touch)
up	The button was released within a short time i.e. a short press has occurred
release	The button is released after being pressed for over the threshold time
long	Event is sent when the button is still being pressed after the threshold time of 400ms
hold	The HOLD event is repeated every 200ms while the button is still pressed
changed	Event is sent when the value of the object has changed during the event

Tip

To actively see the sent out events you can use an MQTT client app and subscribe to the hasp/# topic.

Common Methods

These are the common methods shared among all objects,

Method	Parameters	Description
clear		Delete the children from the object
delete		Delete the object and its children from the page
to_front		Bring the object to the front on the page
to_back		Send the object to the back on the page

Example commands:

p1b5.delete
p1b3.to_front

Object Types

Each object type is an ID that indicates which object type that line represents. Besides the common properties listed above, each object type can have specific properties.

Text Label

obj:label

Property	Value	Default	Description
text	string	"Text"	The text of the label, \n for line break. Can also be a variable.
mode	string	crop	The wrapping mode of long text labels: expand Expand the object size to the text size break Keep the object width, break the too long lines and expand the object height dots Keep the size and write dots at the end if the text is too long scroll Keep the size and roll the text back and forth loop Keep the size and roll the text circularly crop Keep the size and crop the text out of it
align	string	left	Text alignment: left, center, right

It's possible to set the color of characters in the text indvidually, just prefix the text to be re-colored with a #RRGGBB hexadecimal color code and a space, and close with a single hash # tag.

Example jsonl

{"page":1,"id":1,"obj":"label","x":10,"y":5,"w":150,"h":50,"text":"\uE64A Hello world!"}
{"page":1,"id":1,"obj":"label","x":10,"y":5,"w":150,"h":50,"text":"#0000FF \uE64A# #FF0000 Hello# #008000 world#!"}

Button

obj:btn

Property	Value	Default	Description
toggle	bool	false	When enabled, creates a toggle-on/toggle-off button. If false, creates a normal button
val	int16	0	The value: 0 = untoggled, 1 = toggled
text	string	""	The text of the label
mode	string	expand	The wrapping mode of long text labels. expand Expand the object size to the text size break Keep the object width, break the too long lines and expand the object height dots Keep the size and write dots at the end if the text is too long scroll Keep the size and roll the text back and forth loop Keep the size and roll the text circularly crop Keep the size and crop the text out of it
align	string	left	Text alignment: left, center, right

Similar to the text label, it's possible to set the color of characters in the text indvidually, just prefix the text to be re-colored with a #RRGGBB hexadecimal color code and a space, and close with a single hash # tag.

Example jsonl

{"page":1,"id":2,"obj":"btn","x":10,"y":40,"w":105,"h":90,"toggle":false,"text":"Normal Button","mode":"break","align":"center"}
{"page":1,"id":3,"obj":"btn","x":125,"y":40,"w":105,"h":90,"toggle":true,"text":"#FFD700 Toggle# Button","mode":"break","align":"center"}

Normal buttons (toggle=false) send touch events while they occur:

Short touch:

{"event":"down"}
{"event":"up"}

Long press:

{"event":"down"}
{"event":"long"}
{"event":"hold"}
{"event":"hold"}
{"event":"release"}

Toggle buttons (toggle=true) send out the old value in the down event and the new value in the up event when released:

Toggle ON:

{"event":"down","val":0}
{"event":"up","val":1}

Toggle OFF:

{"event":"down","val":1}
{"event":"up","val":0}

Switch

obj:switch

Property	Value	Default	Description
val	bool	0	1 = on, 0 = off
bg_color10	color	0	changes indicator color
bg_color20	color	0	changes knob color
radius20	int16	depends on theme	changes knob corner radius (also see radius)

Example jsonl

{"page":1,"id":4,"obj":"switch","x":125,"y":145,"w":105,"h":55,"radius":15}

Events generated by switch are similar to the ones generate by the toggle buttons.

Checkbox

obj:checkbox

Property	Value	Default	Description
val	int16	0	1 = checked 0 = unchecked
text	string	"Checkbox"	The label of the checkbox

Note

The checkbox object ignores the w and h attribute. These are calculated based on the font and text.

Example jsonl

{"page":1,"id":5,"obj":"checkbox","x":10,"y":145,"w":105,"text":" Checkbox"}

Events generated by checkbox are similar to the ones generate by the toggle buttons.

Progress Bar

obj:bar

Property	Value	Default	Description
min	int16	0	minimum value of the indicator
max	int16	100	maximum value of the indicator
val	int16	0	current value of the indicator
start_value	int16	0	optional minimal allowed value of the indicator

Vertical bars can be created if the width of the object is smaller than its height.

Note

min, max, val and start_value also support negative values.

Slider

obj:slider

Property	Value	Default	Description
min	int16	0	minimum value of the indicator
max	int16	100	maximum value of the indicator
val	int16	0	current value of the indicator
start_value	int16	0	optional minimal allowed value of the indicator

Vertical sliders can be created if the width of the object is smaller than its height.

Note

min, max, val and start_value also support negative values.

Example jsonl

{"page":1,"id":6,"obj":"slider","x":20,"y":250,"w":200,"h":20,"min":15,"max":35}

While pressing and dragging the slider object the following events are sent: down (old value), changed (repeatedly until released) and up (value at the moment of releasing it):

{"event":"down","val":21}
{"event":"changed","val":22}
{"event":"changed","val":23}
{"event":"changed","val":25}
{"event":"changed","val":27}
{"event":"changed","val":29}
{"event":"up","val":31}

Arc

obj:arc

Property	Value	Default	Description
min	int16	0	minimum value of the indicator
max	int16	100	maximum value of the indicator
val	int16	0	current value of the indicator
rotation	int16	0	offset to the 0 degree position
type	0-2	0	0 = normal, 1 = symmetrical, 2 = reverse
adjustable	bool	false	Add knob that the user can operate to change the value
start_angle	0-360		start angle of the arc background (see note)
end_angle	0-360		end angle of the arc background (see note)
start_angle10	0-360		start angle of the arc indicator (see note)
end_angle10	0-360		end angle of the arc indicator (see note)

Note

Zero degree is at the middle right (3 o'clock) of the object and the degrees are increasing in a clockwise direction. The angles should be in the [0-360] range.
min, max and val also support negative values.

Tip

To adjust the size of the knob, use pad_top20, pad_bottom20, pad_left20, pad_right20 styling properties. If you increase the knob beyond the margins of the object, you also need to increase pad_top, pad_bottom, pad_left, pad_right for the arc itself.
Check out value styling to display a textual value in the middle of the arc.

Example jsonl

{"page":1,"id":9,"obj":"arc","x":20,"y":75,"w":200,"h":200,"min":15,"max":35,"border_side":0,"type":0,"rotation":0,"start_angle":135,"end_angle":45,"start_angle10":135,"end_angle10":45,"adjustable":true}

While pressing and dragging the arc object the following events are sent: down (old value), changed (repeatedly until released) and up (value at the moment of releasing it):

{"event":"down","val":21}
{"event":"changed","val":22}
{"event":"changed","val":23}
{"event":"changed","val":25}
{"event":"changed","val":27}
{"event":"changed","val":29}
{"event":"up","val":31}

Dropdown List

obj:dropdown

Property	Value	Default	Description
options	string	""	List of items separated by \n
val	int16	0	The number of the selected item
text	string	""	Read-only The text of the selected item
direction	byte	0	Direction where the dropdown expands: 0 = down, 1 = up, 2 = left, 3 = right Note: up and down are superseeded by the screen size.
show_selected	bool	true	Show the selected option or a static text
max_height	int16	3/4 of screen height	The maximum height of the open drop-down list

Method	Parameters	Description
open		To manually open the drop-down list
close		To manually close the drop-down list

To change the currently selected item, use the val attribute.
To change the items in the list, use the options attribute.

Example jsonl

{"page":1,"id":10,"obj":"dropdown","x":10,"y":205,"w":105,"h":30,"options":"Apple\nBanana\nOrange\nMelon"}

When the item is changed both val and text of the newly selected item are send out accompanied by the change event.

Roller

obj:roller

Property	Value	Default	Description
options	string	""	List of items separated by \n
val	int16	0	The number of the selected item
text	string	""	Read-only The text of the selected item
rows	int8	3	The number of rows that are visible Use this property instead of h to set object height
mode	0..1	0	Roller mode: 0 = normal (finite), 1 = infinite
align	string	center	Text alignment: left, center, right

To change the currently selected item, use the val attribute.
To change the items in the list, use the options attribute.

Example jsonl

{"page":1,"id":11,"obj":"roller","x":125,"y":205,"w":105,"h":30,"options":"Apple\nBanana\nOrange\nMelon","mode":1}

When the item is changed both val and text of the newly selected item are send out accompanied by the change event.

Line Meter

obj:linemeter

Property	Value	Default	Description
min	int16	0	minimum value of the indicator
max	int16	100	maximum value of the indicator
val	int16	0	current value of the indicator
angle	0-360	240	angle between start and end of the scale
line_count	uint16	31	tick count of the scale
rotation	0-360	0	offset for the scale angles to rotate it
type	0-1	0	0 = indicator lines are activated clock-wise 1 = indicator lines are activated counter-clock-wise

Use line and scale properties to customize.

Note

min, max and val also support negative values.

Example jsonl

{"page":1,"id":12,"obj":"linemeter","x":20,"y":70,"w":200,"h":200,"value_str":"Temp","val":75,"line_count":35,"line_rounded":1}

Gauge

obj:gauge

Property	Value	Default	Description
min	int16	0	minimum value of the indicator
max	int16	100	maximum value of the indicator
val	int16	0	current value of the indicator
critical_value	int16	80	scale color will be changed to scale_end_color after this value
label_count	uint8		number of labels (and major ticks) of the scale
line_count	uint16	31	number of minor ticks of the entire scale
angle	0-360	240	angle between start and end of the scale
rotation	0-360	0	offset for the gauge's angles to rotate it
format	uint16	0	divider for major tick values

To strip trailing zero's of major tick labels the format divider can be used to scale the values before printing:

• 0 : print the major tick value as is
• 1 : strip 1 zero, i.e. divide tick value by 10 before printing the major tick label
• 2 : strip 2 zeros, i.e. divide tick value by 100 before printing the major tick label
• 3 : strip 3 zeros, i.e. divide tick value by 1000 before printing the major tick label
• 4 : strip 4 zeros, i.e. divide tick value by 10000 before printing the major tick label

Only these values are allowed, arbitrary numbers are not supported.

Note

min, max and val also support negative values.

Example jsonl

{"page":1,"id":13,"obj":"gauge","x":20,"y":70,"w":200,"h":200}

Use scale properties to customize.

Tabview

obj:tabview

A tabview is an object that can hold multiple tab objects. You first create the tabview object and then add tab objects to it.

Property	Value	Default	Description
val	int8	0	The number of the active tab, starting at 0
text	string	""	The name of the active tab
btn_pos	0..4	1	Position of the tab buttons: 0 = none 1 = top 2 = bottom 3 = left 4 = right
count	uint16	0	Read-only The number of tabs of the tabview

To change the currently visible tab, use the val attribute after all tabs have been added.

Note

To adjust the height of the tab buttons row, use pad_top40 and pad_bottom40 styling properties. Accepts also negative values.
To adjust the text size of the tab names, use the text_font40 styling property.

Read further down to learn now to add tabs to the tabview.

Tab

obj:tab

Property	Value	Default	Description
parentid	int8	0	The id of the tabview object to which this tab is added
text	string	"Tab"	The name of tab button

Set the parent object (which tabview the tabs belong to) by referencing the parentid when creating the tab. To add other objects to these tabs, set the parentid when creating those objects to the id of the tab you wamt them to appear on.

Example jsonl

{"page":1,"id":14,"obj":"tabview","btn_pos":1,"y":180}
{"page":1,"id":51,"obj":"tab","parentid":14,"text":"Tab 1"}
{"page":1,"id":52,"obj":"tab","parentid":14,"text":"Tab 2"}
{"page":1,"id":53,"obj":"tab","parentid":14,"text":"Tab 3"}
{"page":1,"id":61,"obj":"switch","x":20,"y":10,"w":60,"h":30,"parentid":51,"radius":25,"radius20":25}
{"page":1,"id":71,"obj":"dropdown","x":15,"y":10,"w":110,"h":30,"parentid":52,"options":"Apple\nBanana\nOrange\nMelon"}
{"page":1,"id":81,"obj":"checkbox","x":15,"y":10,"w":110,"h":30,"parentid":53,"text":" Nice tabview"} 

Color picker

obj:cpicker

Property	Value	Default	Description
color	color	0	The selected color in html format #rrggbb
scale_width	uint16	25	The width of the color gradient of the circle
pad_inner	int16	10	The padding between the circle and the inner preview circle

The object will automatically adjust based on the w and h properties: when the object is longer then it is height a rectangular color picker is created, otherwise it will be circular.

By long pressing the inner preview circle, the color picker will through the color modes: hue > saturation > value. Double-click on the inner preview circle to reset the current value.

Setting Color

Example MQTT commands:

hasp/<nodename>/command/p0b2.color 13891
hasp/<nodename>/command/p1b5.color silver
hasp/<nodename>/command/p2b3.color #C0C0C0

Events

While pressing and dragging the cpicker object the following events are sent: down (old color), changed (repeatedly until released) and up (value at the moment of releasing it):

{"event":"down","color":"#8300ff","r":131,"g":0,"b":255}
{"event":"changed","color":"#7300ff","r":115,"g":0,"b":255}
{"event":"changed","color":"#6200ff","r":98,"g":0,"b":255}
{"event":"up","color":"#6200ff","r":98,"g":0,"b":255}

Spinner

obj:spinner

Property	Value	Default	Description
speed	int16	1000	The time for 1 turn in ms
direction	int16	0	0 = clockwise, 1 = counter-clockwise
angle	0-360	60	The length of the spinning segment in degrees
type	0-2	0	0 = slow down on the top, 1 = slow down and stretch, 2 = constant speed no stretch
line_width	int16	20	The width of the background circle
line_width10	int16	20	The width of the spinning segment
line_color	color	depends on theme	color of the background circle
line_color10	color	depends on theme	color of the spinning segment

Tip

Check out background, border, and line styling to adjust other aspects of the appearance.

Note

Placing objects over/under the spinner will increase the CPU load because all objects need to be redrawn constantly.

Example jsonl

{"page":1,"id":15,"obj":"spinner","x":180,"y":50,"w":36,"h":36,"bg_opa":0,"border_width":0,"line_width":6,"line_width10":6,"angle":80,"line_color":"white","line_color10":"green"}

LED Indicator

obj:led

Property	Value	Default	Description
val	byte	0	The brightness of the indicator [0..255]

Button Matrix

obj:btnmatrix

Property	Value	Default	Description
options	json array	"Text"	Json array of strings where each element is the label of a button. Use "\n" for a new line of buttons
align	string	center	Text alignment: left, center, right
toggle	bool	false	All buttons behave as toggle buttons or normal buttons
one_check	bool	false	Allow only one button to be checked (toggled) at once
val	int8	0	The number of the active button, starting at 0. In conjunction with toggle and one_check set it to -1 to deactivate all buttons

The styling properties apply to all buttons in the matrix. To change the color of a single label you can prefix the text with a #RRGGBB hexadecimal color code and close with a single hash # tag.

Example jsonl

{"page":1,"id":20,"obj":"btnmatrix","x":10,"y":10,"w":220,"h":150,"options":["#FF0000 Red Text#","#0000FF Cyan Text#","\n","#FFFF00 Yellow Text#"],"toggle":1,"one_check":1}

Messagebox

obj:msgbox

Property	Value	Default	Description
text	string	""	The text of the message to be displayed.
options	json array	["OK"]	Json array of strings where each element is the label of a button
modal	bool	false	Make the messagebox a modal dialog requiring user input
auto_close	int16	0	Close the pop-up message automatically after this number of milliseconds have passed

The Message boxes act as a pop-up. The default width is the horizontal screen size, the height adjusts according to the contents of the message. The pop-up is centered on the screen.

Note

The messagebox object is automatically deleted when it is closed. You will need to create it again using jsonl to pop-up a new message.

Example jsonl

{"page":1,"id":24,"obj":"msgbox","text":"A message box with two buttons","options":["Apply","Close"]}

Line

obj:line

Property	Value	Default	Description
points	JSON array	""	The name of the image file
auto_size	bool	true	Automatically set the size of the line object to the outer bounds
y_invert	bool	false	The y direction might be counter-intuitive in some cases so the y coordinates can be inverted

The points parameter is a JSON array of [x,y] coordinates, for example [[10,25],[100,25],[100,0]].

Example jsonl

{"page":1,"id":33,"obj":"line","points":[[10,25],[100,25],[100,0]],"auto_size":0,"y_invert":1}

Image

obj:img

Property	Value	Default	Description
src	string	""	The name of the image file
auto_size	bool	true	Automatically set the size of the image object to the image source
offset_x	int16	0	Shift the picture horizontally relative to the image object
offset_y	int16	0	Shift the picture vertically relative to the image object
zoom	uint16	256	A larger value enlarges the images (e.g. 512 double size), a smaller value shrinks it (e.g. 128 half size). Fractional scale works as well. E.g. 281 for 10% enlargement.
angle	int16	0	Rotate the picture around its pivot point. Angle has 0.1 degree precision, so for 45.8° use 458.
pivot_x	int16	H center	The pivot point of the rotation, by default centered
pivot_y	int16	V center	The pivot point of the rotation, by default centered
antialias	bool	false	The quality of the angle and zoom transformation. With enabled anti-aliasing the transformations has a higher quality but they are slower.

Note

You can use image_recolor and image_recolor_opa from the image styling properties to apply a color overlay mask.

Either PNG or BIN image files are supported, from flash:

• PNG image are decoded and kept in memory, thus you'll be able to display full-screen images only if your microcontroller has installed PSram memory, else you will be limited to small icons or BIN files.

• BIN images are not stored in memory and are read from flash each time. This will be slower but allows the use of larger images even if your microcontroller doesn't have PSram.

• BIN images from flash do not support zoom or angle transformations.

• Use the online LVGL Image Converter to create BIN files. Set the output format to Binary or Binary RGB565.

Example jsonl

{"page":1,"id":34,"obj":"img","src":"L:/image.png","auto_size":0,"w":50}

Base Object

obj:obj

The Base Object can be directly used as a simple, empty widget. It is nothing more then a (rounded) rectangle.

You can use it as a background shape for other objects by putting its jsonl line before the object. It catches touches!

Example jsonl

{"page":1,"id":50,"obj":"obj","x":5,"y":35,"w":230,"h":250,"click":0}

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Last update: 2023-12-09