Software Keyboard
The software keyboard expects to be passed three IStorages via PushInData.
Common Arguments
The first IStorage passed to this applet should contain the common library applet arguments. This is populated by nn::la::CommonArgumentsWriter and has the following format.
| Offset | Size | Typical Value | Notes |
|---|---|---|---|
| 0x0 | 4 | 1 | Common Arguments version |
| 0x4 | 4 | 0x20 | Common Arguments size |
| 0x8 | 4 | 5 | Library applet version (some kind of API version?) |
| 0xC | 4 | 0 | Theme color |
| 0x10 | 1 | 0 | Play startup sound |
| 0x18 | 8 | N/A | System tick (see svcGetSystemTick) |
| 0x20 | End of struct |
KeyboardConfig
The second IStorage passed to this applet should contain the configuration for the keyboard.
| Offset | Size | Typical Value | Notes |
|---|---|---|---|
| 0x0 | 4 | 2 | |
| 0x4 | 18 | u"OK" | UTF-16 text displayed in the submit button |
| 0x16 | 2 | 0 | UTF-16 "left optional symbol key" |
| 0x18 | 2 | 0 | UTF-16 "right optional symbol key" |
| 0x1A | 1 | 0 | |
| 0x1C | 4 | 0 | Key set disable bitmask |
| 0x20 | 4 | 1 | Initial cursor position (0 = start of string, 1 = end of string) |
| 0x24 | 130 | u"" | UTF-16 header text |
| 0xA6 | 258 | u"" | UTF-16 sub text |
| 0x1A8 | 514 | u"" | UTF-16 guide text |
| 0x3AC | 4 | 0 | String length limit (defaults to 500?) |
| 0x3B0 | 4 | 0 | |
| 0x3B4 | 4 | 0 | Password flag (0 = not password, 1 = password) |
| 0x3B8 | 4 | 1 | |
| 0x3BC | 2 | 1 | |
| 0x3BE | 1 | 1 | Draw background (0 = no, 1 = yes) |
| 0x3C0 | 4 | 20 | Offset of initial string in work buffer (or 0) |
| 0x3C4 | 4 | 0 | Size of initial string in work buffer (bytes) |
| 0x3C8 | 4 | 2024 | Offset of user dictionary in work buffer (or 0) |
| 0x3CC | 4 | 0 | Length of user dictionary (number of entries) |
| 0x3D0 | 1 | 0 | #Text check enable |
| 0x3D8 | 8 | 0 | #Text check callback function address. Not sure why this is included here |
| 0x3E0 | End of struct |
If the length limit is <= 32, the text entry box will be a single row and show the header/sub text. Otherwise, it will use multiple rows and the header/sub text will not be shown.
Each entry in the user dictionary is 100 bytes long.
Key Set Disable Bitmask
Various bits in this field disable certain keys on the keyboard. This list is incomplete.
0x02: disable ' ' 0x04: disable '@' 0x08: disable '%' 0x10: disable '\' and '/' 0x40: disable numbers 0x80: used for download codes
Work Buffer
This is the third IStorage passed to this applet. It is a transfer memory storage. The transfer memory should have size 0x1000 (0xd000 in certain cases) and permissions 0.
The layout of the work buffer doesn't seem to matter as long as the offsets in the #KeyboardConfig are adjusted, but official code lays it out like this.
| Offset | Size | Notes |
|---|---|---|
| 20 (decimal) | Unknown | UTF-16 initial string |
| 2024 (decimal) | Unknown | User dictionary |
Text Check
If text checking is enabled in #KeyboardConfig, text will be checked when the submit button is pressed. First, swkbd sends the text via PushInteractiveOutData.
| Offset | Size | Notes |
|---|---|---|
| 0x0 | 0x4 | Buffer size |
| 0x4 | Variable | UTF-16 text |
| 0x7d4 | Size of storage |
The application then has an opportunity to validate or reject the text. It creates a new IStorage, writes the response to it, and sends it via PushInteractiveInData.
| Offset | Size | Notes |
|---|---|---|
| 0x0 | 0x4 | Status (0 = OK, 1 = bad) |
| 0x4 | Variable | UTF-16 error message (shown in a dialog box) |
| 0x7d4 | Size of storage |
Output
When either the submit button is pressed and input has been validated, or the user cancels the text entry, swkbd will push its response and exit. The response IStorage has the following format.
| Offset | Size | Notes |
|---|---|---|
| 0x0 | 0x4 | Result code (0 = OK, 1 = Cancel) |
| 0x4 | Variable | UTF-16 text |
| 0x7d8 | Size of storage |