I am trying to create a GUI with a series of text entry fields:
package main
import ("github.com/andlabs/ui")
func main() {
ui.Main(makeMainWin)
}
func makeMainWin(){
var entlist = []ui.NewEntry //Error here. How to declare an array of ui.NewEntry?
var box = ui.NewVerticalBox()
for i,_ := range [5]int{} {
println(i)
box.Append(ui.NewEntry(), false)
}
var mainWindow = ui.NewWindow("Hello", 200, 100, false)
mainWindow.SetChild(box)
mainWindow.OnClosing( func (*ui.Window) bool {
ui.Quit(); return true } )
mainWindow.Show()
}
However, there is error on var entlist = []NewEntry
I am not able to create an array of NewEntry components. I have tried []ui.NewEntry, []*ui.NewEntry, []ui.NewEntry() and []*ui.NewEntry()
Where is the problem and how can it be solved? Thanks for your help.
ui.NewEntry returns *Entry, therefore your slice should be declared as:
var entlist []*ui.Entry
Related
I have a core data / document-driven macOS app, using Swift and I struggle on combining the out-of-the-box spell checking API with an NSDocument (NSPersistentDocument in my case)
It took me more time than it should take, but this is what I got, mostly guided by this great answer:
class VTDocument: NSPersistentDocument, NSChangeSpelling {
[...]
private let spellchecker = SpellChecker()
#IBAction func showGuessPanel(_ sender: Any?){
spellchecker.startSpellCheck(nodes: Array(db.nodes), tag: 0)
}
#IBAction #objc func changeSpelling(_ sender: Any?){
spellchecker.replace(with: "Test")
}
This is leading me to see the NSSpellChecker.spellingPanel, correctly showing the word to correct. However, the changeSpelling function should be "called" by the panel but is never called. The above spellChecker is a simple wrapper around the NSSpellChecker that keeps the status between function calls.
The SpellChecker class looks like this.
import Cocoa
class SpellChecker {
let checker = NSSpellChecker.shared
let count: UnsafeMutablePointer<Int> = UnsafeMutablePointer<Int>.allocate(capacity: 1)
var nodes = Array<Node> ()
var nodeNr = 0
var stringPos = 0
var range: NSRange = NSRange()
func startSpellCheck(nodes: [Node], tag: Int ) {
self.nodes = nodes
nodeNr = 0
stringPos = 0
continueChecking()
}
func continueChecking(){
if nodes.count == 0 {
return
}
if nodeNr >= nodes.count {
checker.updateSpellingPanel(withMisspelledWord: "")
checker.spellingPanel.orderFront(self)
return
}
if let nodeText = nodes[nodeNr].label {
range = checker.checkSpelling(of: nodeText, startingAt: stringPos, language: nil, wrap: false, inSpellDocumentWithTag: 0, wordCount: count)
if count.pointee > 0 {
stringPos = range.lowerBound
checker.updateSpellingPanel(withMisspelledWord: nodeText[range])
checker.spellingPanel.orderFront(self)
return
}
}
nodeNr = nodeNr + 1
continueChecking()
}
func replace(with: String){
if let nodeText = nodes[nodeNr].label {
let text = nodeText as NSString
text.replacingCharacters(in: range, with: with)
nodes[nodeNr].label = text as String
}
}
}
I'm hoping someone may be able to help i'm using Xcode 8 and swift 3
I have a playground file Xcode 7 swift 2 that involves a Midi callback for Midi Input everything works fine in 7
I tried a conversion to 8 and it brought up errors regarding memory and a few name changes mostly of what i believe to be non serious i also redefined the infinite loop using PlaygroundSupport
However the error i cannot get over involves MyMIDIReadProc at
MIDIInputPortCreate(midiClient, "MidiTest_InPort", MyMIDIReadProc, nil, &inPort);
The error says
Cannot convert value of type '(pktList: UnsafePointer, readProcRefCon: UnsafeMutablePointer, srcConnRefCon: UnsafeMutablePointer) -> Void' to expected argument type 'MIDIReadProc' (aka '#convention(c) (UnsafePointer, Optional>, Optional>) -> ()')
My understanding is that it needs a #convention(c) wrapper of some description inserted. I think i'm on the right track because you can wrap a function but my knowledge of where to put it has run out. Again i was hoping some one might be able to advise
Thanks for reading
apologies for any bad language as i'm self taught
Here is the original Xcode 7 code
import Cocoa
import CoreMIDI
import XCPlayground
func getDisplayName(obj: MIDIObjectRef) -> String
{
var param: Unmanaged<CFString>?
var name: String = "Error";
let err: OSStatus = MIDIObjectGetStringProperty(obj, kMIDIPropertyDisplayName, ¶m)
if err == OSStatus(noErr)
{
name = param!.takeRetainedValue() as String
}
return name;
}
func MyMIDIReadProc(pktList: UnsafePointer<MIDIPacketList>,
readProcRefCon: UnsafeMutablePointer<Void>, srcConnRefCon: UnsafeMutablePointer<Void>) -> Void
{
let packetList:MIDIPacketList = pktList.memory;
let srcRef:MIDIEndpointRef = UnsafeMutablePointer<MIDIEndpointRef>(COpaquePointer(srcConnRefCon)).memory;
print("MIDI Received From Source: \(getDisplayName(srcRef))");
var packet:MIDIPacket = packetList.packet;
for _ in 1...packetList.numPackets
{
let bytes = Mirror(reflecting: packet.data).children;
var dumpStr = "";
// bytes mirror contains all the zero values in the ridiulous packet data tuple
// so use the packet length to iterate.
var i = packet.length;
for (_, attr) in bytes.enumerate()
{
dumpStr += String(format:"$%02X ", attr.value as! UInt8);
--i;
if (i <= 0)
{
break;
}
}
print(dumpStr)
packet = MIDIPacketNext(&packet).memory;
}
}
var midiClient: MIDIClientRef = 0;
var inPort:MIDIPortRef = 0;
var src:MIDIEndpointRef = MIDIGetSource(0);
MIDIClientCreate("MidiTestClient", nil, nil, &midiClient);
MIDIInputPortCreate(midiClient, "MidiTest_InPort", MyMIDIReadProc, nil, &inPort);
MIDIPortConnectSource(inPort, src, &src);
// Keep playground running
XCPlaygroundPage.currentPage.needsIndefiniteExecution = true;
And here is the Xcode 8 code converted
var str = "Hello, playground"
import Cocoa
import CoreMIDI
import XCPlayground
import PlaygroundSupport
func getDisplayName(obj: MIDIObjectRef) -> String
{
var param: Unmanaged<CFString>?
var name: String = "Error";
let err: OSStatus = MIDIObjectGetStringProperty(obj, kMIDIPropertyDisplayName, ¶m)
if err == OSStatus(noErr)
{
name = param!.takeRetainedValue() as String
}
return name;
}
func MyMIDIReadProc(pktList: UnsafePointer<MIDIPacketList>,
readProcRefCon: UnsafeMutablePointer<Void>, srcConnRefCon: UnsafeMutablePointer<Void>) -> Void
{
let packetList:MIDIPacketList = pktList.pointee;
let srcRef:MIDIEndpointRef = UnsafeMutablePointer<MIDIEndpointRef>(OpaquePointer(srcConnRefCon)).pointee;
print("MIDI Received From Source: \(getDisplayName(obj: srcRef))");
var packet:MIDIPacket = packetList.packet;
for _ in 1...packetList.numPackets
{
let bytes = Mirror(reflecting: packet.data).children;
var dumpStr = "";
var i = packet.length;
for (_, attr) in bytes.enumerated()
{
dumpStr += String(format:"$%02X ", attr.value as! UInt8);
i -= 1;
if (i <= 0)
{
break;
}
}
print(dumpStr)
packet = MIDIPacketNext(&packet).pointee;
}
}
var midiClient: MIDIClientRef = 0;
var inPort:MIDIPortRef = 0;
var src:MIDIEndpointRef = MIDIGetSource(0);
MIDIClientCreate("MidiTestClient", nil, nil, &midiClient);
MIDIInputPortCreate(midiClient, "MidiTest_InPort", MyMIDIReadProc, nil, &inPort);
MIDIPortConnectSource(inPort, src, &src);
PlaygroundPage.current.needsIndefiniteExecution = true
Pointer types are drastically changed in Swift 3. Many C-based APIs' signatures are changed accordingly.
Following those changes manually would be painful. You can make Swift work for you, with a little modification.
Try changing the function header:
func MyMIDIReadProc(pktList: UnsafePointer<MIDIPacketList>,
readProcRefCon: UnsafeMutablePointer<Void>, srcConnRefCon: UnsafeMutablePointer<Void>) -> Void
{
to a closure declaration:
let MyMIDIReadProc: MIDIReadProc = {pktList, readProcRefCon, srcConnRefCon in
Swift infers argument types perfectly in this style.
You may need to fix pointer type conversion:
let srcRef:MIDIEndpointRef = UnsafeMutablePointer<MIDIEndpointRef>(OpaquePointer(srcConnRefCon)).pointee;
to something like this:
//I'm not sure using `!` is safe here...
let srcRef: MIDIEndpointRef = UnsafeMutablePointer(srcConnRefCon!).pointee
(By the way, the equivalent part in your Xcode 7 code is a little bit redundant. You have no need to use intermediate COpaquePointer there.)
In Swift 3, pointers cannot be nil, and nullable pointers are represented with Optionals. You may need many other fixes to work with C-based APIs in Swift 3.
OOPer is pointing (ahem) you in the right direction. Here is a blog post on using Swift 3 Core MIDI along with a working github repo.
Assuming that you're working with CoreMIDI 1.3 or later, you may have more luck using MIDIInputPortCreateWithBlock instead of MIDIInputPortCreate.
This method takes a Swift block as a parameter instead of requiring an #convention(c) function reference, making it more amenable to use within methods belonging to Swift classes, e.g.:
public func midiReadBlock(ptr: UnsafePointer<MIDIPacketList>, _: UnsafeMutableRawPointer?) -> Void {
let list: MIDIPacketList = ptr.pointee
...
}
You may also find these two extensions useful.
This one (derived from here) allows you to iterate directly over a MIDIPacketList using for pkt in list:
extension MIDIPacketList: Sequence {
public func makeIterator() -> AnyIterator<MIDIPacket> {
var iterator: MIDIPacket?
var nextIndex: UInt32 = 0
return AnyIterator {
nextIndex += 1
if nextIndex > self.numPackets { return nil }
if iterator != nil {
iterator = withUnsafePointer(to: &iterator!) { MIDIPacketNext($0).pointee }
} else {
iterator = self.packet;
}
return iterator
}
}
}
and this one adds a method to a MIDIPacket to extract the contents as a [UInt8] instead of having to use the really broken tuple syntax:
extension MIDIPacket {
public var asArray: [UInt8] {
let mirror = Mirror(reflecting: self.data)
let length = Int(self.length)
var result = [UInt8]()
result.reserveCapacity(length)
for (n, child) in mirror.children.enumerated() {
if n == length {
break
}
result.append(child.value as! UInt8)
}
return result
}
}
I'm running below function in my iPad app to get an Item by it's hash key (IdName).
This table only contains an Hashkey (No Range key available) but when I run this, It returns an result object which contains only the HashKey Value (The same which I pass). The other property (IdValue) is not there in the result. What am I doing wrong here?
func getCurrentFinalReportNumber()->Int
{
let dynamoDBObjectMapper = AWSDynamoDBObjectMapper.defaultDynamoDBObjectMapper()
var currentId :Int = -1
dynamoDBObjectMapper .load(DDBIDStoreTableRow.self, hashKey: "FinalReportNumber", rangeKey: nil) .continueWithExecutor(AWSExecutor.mainThreadExecutor(), withBlock: { (task:AWSTask!) -> AnyObject! in
if (task.error == nil) {
if (task.result != nil) {
let resultRow :DDBIDStoreTableRow = task.result as! DDBIDStoreTableRow
print(resultRow.IdValue)
currentId = Int(resultRow.IdValue!)
}
} else {
print("Error: \(task.error)")
let alert = SCLAlertView()
alert.addButton("Close", colorButtonBackground: Constants.InspectionTypes.colorClose) {}
alert.showCloseButton = false
alert.showError("", subTitle: (task.error?.description)!)
}
return nil
}).waitUntilFinished()
return currentId
}
class DDBIDStoreTableRow :AWSDynamoDBObjectModel ,AWSDynamoDBModeling {
var IdName:String? //HK
var IdValue:Int? = -1
class func dynamoDBTableName() -> String! {
return AWSIDStoreDynamoDBTableName
}
class func hashKeyAttribute() -> String! {
return "IdName"
}
//MARK: NSObjectProtocol hack
override func isEqual(object: AnyObject?) -> Bool {
return super.isEqual(object)
}
override func `self`() -> Self {
return self
}
}
Just found the mistake. Problem is in the data type of the mapping class. Earlier it was
var IdValue:Int? = -1
But once I change the Int to NSNumber as below. It started to work fine
var IdValue:NSNumber? = -1
let verbList: [String] = ["hacer", "ser", "estar"]
let POVList: [String] = ["él / usted","ella / usted","ellas / ustedes","ellos / ustedes","tú","yo","nosotros",]
let correctConjugation: [[String]] = [["hace","hace","hacen","hacen","haces","hago","hacemos"], ["es","es","son","son","eres","soy","somos"], ["está","está","estan","estan","estas","estoy","estamos"]]
func randomVerb() -> Int { //creates and returns a random number for the prefix arrray
var randomVerb = Int(arc4random_uniform(3))
return randomVerb
}
func randomPrefix() -> Int { //creates and returns a random number for the verb array
var randomPrefix = Int(arc4random_uniform(7))
return randomPrefix
}
#IBAction func changeVerb(sender: AnyObject) {
Verb.text = verbList[randomVerb()]
POV.text = POVList[randomPrefix()]
userResponse.backgroundColor = UIColor.whiteColor()
userResponse.text = ""
}
#IBAction func checkResponse(sender: AnyObject) {
var userResponseA: String
userResponseA = userResponse.text
if (userResponseA == correctConjugation[randomVerb()[randomPrefix()]]){
userResponse.backgroundColor = UIColor.greenColor()
} else {
userResponse.backgroundColor = UIColor.redColor()
}
}
So I get two errors here (in the if statement in checkResponse): first, "int does not have a member named 'subscript'" and if I just take out the call for the function in the if statement I get: "'String' is not convertible to 'Mirror Disposition'"
I really have no idea why this is not working. Bear with me, as I am an Xcode noob just trying to get a better grade in spanish.
Very close - just need to have your subscripts separated:
if (userResponseA == correctConjugation[randomVerb()][randomPrefix()]) {
// ...
}
When working with an array of arrays (in this case correctConjugation), each subscript takes you one level down.
For the other issue, you want a couple variables to hold the current verb and prefix indexes:
class VC: UIViewController {
// list declarations here
var verbIndex = 0
var povIndex = 0
#IBAction func changeVerb(sender: AnyObject) {
verbIndex = randomVerb()
povIndex = randomPrefix()
Verb.text = verbList[verbIndex]
POV.text = POVList[povIndex]
userResponse.backgroundColor = UIColor.whiteColor()
userResponse.text = ""
}
#IBAction func checkResponse(sender: AnyObject) {
var userResponseA = userResponse.text
if (userResponseA == correctConjugation[verbIndex][povIndex]){
userResponse.backgroundColor = UIColor.greenColor()
} else {
userResponse.backgroundColor = UIColor.redColor()
}
}
}
Essentially, I have one function wherein several objects have been created, and another function where I am trying to access these objects. As seen below:
func createButtons() {
var myButton01 = BigButton.createbutton()
var myButton02 = BigButton.createbutton()
}
As you can see I am trying to access the objects to pair them up with keys in a dictionary.
func setupConstraints() {
var myButtonDictionary = ["myButton01": myButton01, "myButton02": myButton02]
...
}
How would I go about making them accessible without having to move the second function into the first function. Is there any way to make the objects accessible to other functions?
Make myButton01 and myButton02 properties of the class you're working in, or if there is no class, just put the variables outside the functions.
This is how you would do it if there was no class:
var myButton01: BigButton? = nil
var myButton02: BigButton? = nil
func createButtons() {
var myButton01 = BigButton.createbutton()
var myButton02 = BigButton.createbutton()
}
func setupConstraints() {
var myButtonDictionary = ["myButton01": myButton01!, "myButton02": myButton02!]
...
}
Typically you would have these functions in some other construct, like a class and those objects would be instance variables.
class BigButton {
class func createButton() -> BigButton {
return BigButton()
}
}
class Foo {
var myButton01: BigButton?
var myButton02: BigButton?
func createButtons() {
myButton01 = BigButton.createButton()
myButton02 = BigButton.createButton()
}
func setupConstraints() {
var myButtonDictionary = ["myButton01": myButton01, "myButton02": myButton02]
}
}