go-osk is an experimental on-screen keyboard, primarily aimed at those developing for Kobo ereaders.
This was dreamed up on a lazy Sunday afternoon. It may or may not evolve beyond its current form...
go-osk can be obtained using go get:
go get github.com/shermp/go-osk/...
This repository holds no usage example. However go-kobo-input does include a sample application which makes use of the onscreen keyboard.
Keymaps are stored as a JSON file. The JSON gets converted to the osk at run-time. A sample keymap is included in the repository.
An abridged keymap is as follows:
{
"lang": "en_us",
"kbMargins": {
"top": 0.60,
"bottom": 0.05,
"left": 0.0,
"right": 0.0
},
"totalKeyWidth": 3,
"totalRowHeight": 1.8,
"rows": [
{
"rowHeight": 0.8,
"keys": [
{
"isPadding": false,
"keyType": 0,
"keyWidth": 1,
"char": "1"
},
{
"isPadding": false,
"keyType": 0,
"keyWidth": 1,
"char": "2"
},
{
"isPadding": false,
"keyType": 0,
"keyWidth": 1,
"char": "3"
}
]
},
{
"rowHeight": 1,
"keys": [
{
"isPadding": true,
"keyType": 0,
"keyWidth": 1,
"char": ""
},
{
"isPadding": false,
"keyType": 0,
"keyWidth": 1,
"char": "q"
},
{
"isPadding": false,
"keyType": 0,
"keyWidth": 1,
"char": "w"
}
]
}
]
}
The fields are as follows:
| Field | Value |
|---|---|
| "lang" | Keyboard language. Currently unused |
| "kbMargins" | "top" "bottom" "left" "right" margins. Each margin is expressed as a percentage of the screen dimensions. This controls the size and position of the onscreen keyboard. Valid values for each key are 0.0 - 0.8. Each top/bottom and left/right pair must sum to <= 0.8 |
| "totalKeyWidth" | This is a somewhat arbitrary figure. If one assumes that a standard key is one unit wide, then this is how many units make up a row. |
| "totalRowHeight" | The same as above, but for rows. |
| "rows" | An array of rows of the keyboard. Each row contains the following fields. |
| "rowHeight" | The height of the row. This is in proportion to the "totalRowHeight", where the sum of all "rowHeight" values must equal "totalRowHeight" |
| "keys" | Each row contains an array of keys, the fields for which are described below. |
| "isPadding" | This is used to tell the OSK that this 'key' is used merely for visual padding. "keyWidth" is the only other field used when this field is true. |
| "keyType" | This is the type of key, whether it be a standard character, or a control key such as "shift" "backspace" etc. Standard keys have the value 0. |
| "keyWidth" | This is the width of the key, and is proportional to "totalKeyWidth". All keys in a row must sum to "totalKeyWidth" |
| "char" | This is the printable character of the key. |