Import a Mac API struct into Xojo

Targets macOS
1

Suppose a Mac API has the following struct, referenced here: Apple Developer Documentation (with code from here ):

struct MIDISysexSendRequest
{
MIDIEndpointRef destination;
const Byte * data;
UInt32 bytesToSend;
Boolean complete;
Byte reserved[3];
MIDICompletionProc completionProc;
void * completionRefCon;
};
How to import it into Xojo? The intention is to be able to create one so I can send it with the MIDISendSysex CoreMIDI API command.

The Xojo tutorial mainly talks about importing Functions, not structures.

2

You’ll have to manually recreate the structure in Xojo (Insert->Structure). Something like this:

Structure MIDISysexSendRequest
    MIDIEndpointRef As Ptr
    Data As Ptr
    BytesToSend As UInt32
    Complete As Boolean
    Reserved As String*3
    MIDICompletionProc As Ptr
    CompletionRefCon As Ptr
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3

Thank you, barring other solutions I will use that.

Is there a way to embed Swift or Objective-C code into Xojo? The call I would like to execute requires a lot of CoreMIDI variables and functions.

4

What about the following structs:

struct MIDIPacket
{
MIDITimeStamp timeStamp;
UInt16 length;
Byte data[256];
};

and

struct MIDIPacketList
{
UInt32 numPackets;
MIDIPacket packet[1];
};

My current implementations (which do not work):

Structure MIDIPacket
      timestamp As Integer
       length As Uint16
       data As String*256

Structure MIDIPacketList
    numPackets As UInt32
    packet(1) As MidiPacket

A problem I can think of is structs do not support MemoryBlocks (what I would guess equals the ‘Byte’ data type).
So my solution was to assign my binary data to memory block (mb.byte(0) = &hf0 etc), then assign the data string to that memoryblock.

EDIT: Nevermind it works! I forgot to set the packet.length property.

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