SwiftUI: how do I apply formatting to Picker choices? - swiftui

I have a picker (Destination is a CaseIterable enum) and getTabTitle returns a String:
Picker(selection: $which, label: Image(systemName: "text.justify").font(.title)
.frame(width: 50, height: 20, alignment: .trailing)) {
ForEach(Destination.allCases, id: \.self) {
Text(getTabTitle($0)).foregroundColor(Color(UIColor.systemBlue))
}
}
.pickerStyle(MenuPickerStyle())
The foregroundColor modifier is ignored: the menu items are drawn in black on a white background (or vice versa). How do I style the choices? (and is there a better symbol for a menu than the four horizontal lines of the text.justify system image?)
Jeremy

Related

Text with Text.DateStyle in SwiftUI View in Complication alignment

I want to create a complication rendered by a SwiftUI View that contains a label and a timer value.
I want the label to be on the complication background layer, and the timer value to be on the complication foreground layer so that they get tinted separately.
I would like this line of text, comprised of 2 parts, to be centered.
The trouble is, when using Text.DateStyle.timer, the Text behaves differently within a complication vs in a normal view.
In a normal view the Text frame behaves as any other text, only taking the space it needs.
When displayed in a complication, the Text frame expands to fill all the space it can, and the text within is left aligned.
This makes it so I cannot find a way to center the group of 2 Texts.
I tried a somewhat hacky approach with infinite spacers to try to steal the extra space from the Text that has the expanding frame. This works to center the content, but it causes the Text to truncate.
HStack {
Text("T:")
.foregroundColor(.accentColor)
Text(Date(), style: .timer)
.complicationForeground()
}
HStack {
Spacer()
.frame(maxWidth: .infinity)
HStack {
Text("T:")
.foregroundColor(.accentColor)
Text(Date(), style: .timer)
.complicationForeground()
}
Spacer()
.frame(maxWidth: .infinity)
}
A normal preview:
A preview of rendering within complication:
CLKComplicationTemplateGraphicExtraLargeCircularView(
ExtraLargeStack()
)
.previewContext(faceColor: .multicolor)
Edit to show full code
import ClockKit
import SwiftUI
struct ExtraLargeStack: View {
var body: some View {
VStack(alignment: .center) {
HStack {
Text("T:")
.foregroundColor(.accentColor)
Text(Date(), style: .timer)
.complicationForeground()
}
HStack {
Spacer()
.frame(maxWidth: .infinity)
HStack {
Text("T:")
.foregroundColor(.accentColor)
Text(Date(), style: .timer)
.complicationForeground()
}
Spacer()
.frame(maxWidth: .infinity)
}
}
.font(.system(size: 18, weight: .regular))
.lineLimit(1)
}
}
struct ExtraLargeStack_Previews: PreviewProvider {
static var previews: some View {
/// Preview normal view
// ExtraLargeStack()
/// Preview as Complication
CLKComplicationTemplateGraphicExtraLargeCircularView(
ExtraLargeStack()
)
.previewContext(faceColor: .multicolor)
}
}
Edit: Another partial solution
Based on suggestions from #Yrb, an overlay provides a partial solution that may be good enough for my use case.
The following does not fully center the 2 part line, but it is pretty close.
HStack {
// Use placeholder text to create a view with the appropriate size for _most_ timer values that I need to support
Text("L: 00:00 ").hidden()
}
.overlay(
// overlay the real content, which is constrained to the frame created by the hidden placeholder.
HStack(spacing: 5) {
Text("L:")
.foregroundColor(.accentColor)
Text(Date() - 3599, style: .timer)
.complicationForeground()
}
)
So, I figured out what the issue with aligning Text(Date(), style: .timer) is. The timer format from hours on down. The document give this as an example: 2:59 36:59:01. It appears that .timer reserves all of the possible space it needs and then is formatted on that possible space, not the space actually used. There does not appear to be any way to change this behavior, even if your goal is a 5 minute countdown timer.
I think you need to consider slight UI change. I did find that you can change the alignment of the displayed Text with a .timer by using .multilineTextAlignment(), but that is about all you can do. The following code demonstrates this:
struct ExtraLargeStack: View {
var body: some View {
// I removed (alignment: .center) as it is redundant. VStacks default to center
VStack {
// I put the negative spacing to tighten the T: with the timer
VStack(spacing: -6) {
Text("T:")
.foregroundColor(.accentColor)
Text(Date(), style: .timer)
// If you center with .multilineTextAlignment the timer
// will be centered
.multilineTextAlignment(.center)
.complicationForeground()
}
HStack {
HStack {
Text(Date(), style: .timer)
.multilineTextAlignment(.center)
.complicationForeground()
.overlay(
Text("T:")
.foregroundColor(.accentColor)
// This offset would need to be computed
.offset(x: -30, y: 0)
)
}
}
}
.font(.system(size: 18, weight: .regular))
}
}
I left the second timer as an HStack, but I put your Text("T") as an .overlay() with a .offset(). I don't particularly like this as it will be fragile if you attempt to adjust the offset for the additional time units, but if you have a limited range, it may work well enough. Also, if you use .monospaced on the timer text, the computation should be a linear amount.

SwiftUI contextmenu wrong location

I am trying to add a contextmenu to images I display, but when I longpress, the contextmenu opens in a wrong location (see image)
The code I use is:
ForEach(self.document.instruments) { instrument in
Image(instrument.text)
.resizable()
.frame(width: 140, height: 70)
.position(self.position(for: instrument, in: geometry.size))
.gesture(self.singleTapForSelection(for: instrument))
.gesture(self.dragSelectionInstrument(for: instrument))
.shadow(color: self.isInstrumentSelected(instrument) ? .blue : .clear, radius: 10 * self.zoomScale(for: instrument))
.contextMenu {
Button {
print("Deleted selected")
} label: {
Label("Delete", systemImage: "trash")
}
}
}
Update of issue
The issue I still face (as my last comment), is that when I drag an image, there seems to be a delay, as the image remains on its position for a short moment and then moves to the dragged position. I already found out that when I have the contextMenu in the code, the delay dragging happens, when commented out, it works fine.
This is the code I have:
ForEach(self.document.instruments) { instrument in
Image(instrument.text)
.resizable()
.frame(width: 140, height: 70)
.contextMenu {
Button {
print("Deleted selected")
} label: {
Label("Delete", systemImage: "trash")
}
}
.position(self.position(for: instrument, in: geometry.size))
.shadow(color: self.isInstrumentSelected(instrument) ? .blue : .clear, radius: 10 * self.zoomScale(for: instrument))
.gesture(self.singleTapForSelection(for: instrument))
.gesture(self.dragSelectionInstrument(for: instrument))
}
I even tried moving the gestures above the contextmenu, but didn't work.
Please help
Latest Update
Nm, it was only on the simulator, on my physical iPad it works fine
The problem is that your code applies the contextMenu modifier after the position modifier.
Let's consider this slightly modified example:
ZStack {
GeometryReader { geometry in
ForEach(self.document.instruments, id: \.id) { instrument in
Image(instrument.text)
.frame(width: 140, height: 70)
.position(self.position(for: instrument, in: geometry.size))
.contextMenu { ... }
}
}
}
In the SwiftUI layout system, a parent view is responsible for assigning positions to its child views. A view modifier acts as the parent of the view it modifies. So in the example code:
ZStack is the parent of GeometryReader.
GeometryReader is the parent of ForEach.
ForEach is the parent of contextMenu.
contextMenu is the parent of position.
position is the parent of frame.
frame is the parent of Image.
Image is not a parent. It has no children.
(Sometimes the parent is called the “superview” and the child is called the “subview”.)
When contextMenu needs to know where to draw the menu on the screen, it looks at the position given to it by its parent, the ForEach, which gets it from the GeometryReader, which gets it from the ZStack.
When Image needs to know where to draw its pixels on the screen, it looks at the position given to it by its parent, which is the frame modifier, and the frame modifier gets the position from the position modifier, and the position modifier modifies the position given to it by the contextMenu.
This means that the position modifier does not affect where the contextMenu draws the menu.
Now let's rearrange the code so contextMenu is the child of position:
ZStack {
GeometryReader { geometry in
ForEach(self.document.instruments, id: \.id) { instrument in
Image(instrument.text)
.frame(width: 140, height: 70)
.contextMenu { ... }
.position(self.position(for: instrument, in: geometry.size))
}
}
}
Now the contextMenu gets its position from the position modifier, which modifies the position given to it by the ForEach. So in this scenario, the position modifier does affect the where the contextMenu draws the menu.

How to get toolbar separator in SwiftUI?

I would like to get the separator in SwiftUI, but I didn't find the way. This was screenshot from mail.app.
If your view elements are in a HStack (like your mail.app suggest) using Divider() will give you a vertical "separator".
Elsewhere Divider() will give you a horizontal "separator".
You can adjust its size, like this: Divider().frame(width: 123)
You can of course do more things with Dividers, such as set its thickness or height with different color:
HStack {
Divider().frame(width: 5, height: 50).background(Color.blue)
Image(systemName: "line.3.horizontal.decrease.circle")
Divider().frame(width: 10, height: 100).background(Color.pink)
Image(systemName: "envelope")
Divider().frame(width: 15, height: 150).background(Color.green)
}
Here is the right way of doing such thing, do not use Divider, because it has lots of issues. With Divider you cannot control the thickness, also it has issue with updating color, wired Xcode complain in console in some cases, also space issue, it takes more space than it needs. In general it does not worth to use it.
struct ContentView: View {
var body: some View {
HStack {
Group {
Image(systemName: "mail")
Capsule().fill(Color.secondary).frame(width: 2.0)
Image(systemName: "trash")
}
.frame(width: 25, height: 25)
}
}
}
One alternative solution that may be more useful in some cases (e.g if you want a customisable toolbar the accepted solution won't work):
ToolbarItem (placement: .primaryAction) {
HStack {
Divider()
}
}

In SwiftUI, how to fill Path with text color on top of a material?

I'm drawing icons on a toolbar with a material background. The Text and symbol Images are white, but if I draw my own Path, it's gray.
struct ContentView: View {
var body: some View {
HStack {
Text("Hi")
Image(systemName: "square.and.arrow.up.fill")
Path { p in
p.addRect(CGRect(origin: .zero, size: .init(width: 20, height: 30)))
}.fill()
.frame(width: 20, height: 30)
}
.padding()
.background(.regularMaterial)
}
}
I get the same result with .fill(), .fill(.foreground), or .fill(.primary).
Why is it gray? How do I get it to match the white text color?
I find it weird that .white or .black work, but .primary doesn't.
Upon discovering the Material documentation, I found this interesting snippet:
When you add a material, foreground elements exhibit vibrancy, a context-specific blend of the foreground and background colors that improves contrast. However using foregroundStyle(_:) to set a custom foreground style — excluding the hierarchical styles, like secondary — disables vibrancy.
Seems like you have to force a different color (see previous edit which I used the environment color scheme), since hierarchical styles such as .primary won't work by design.
Luckily there is a way around this - you can use colorMultiply to fix this problem. If you set the rectangle to be .white, then the color multiply will make it the .primary color.
Example:
struct ContentView: View {
var body: some View {
HStack {
Text("Hi")
Image(systemName: "square.and.arrow.up.fill")
Path { p in
p.addRect(CGRect(origin: .zero, size: .init(width: 20, height: 30)))
}
.foregroundColor(.white)
.colorMultiply(.primary)
.frame(width: 20, height: 30)
}
.padding()
.background(.regularMaterial)
}
}
There is no issue with code, your usage or expecting is not correct! Text and Image in that code has default Color.primary with zero code! So this is you, that messing with .fill() you can delete that one!
struct ContentView: View {
var body: some View {
HStack {
Text("Hi")
Image(systemName: "square.and.arrow.up.fill")
Path { p in
p.addRect(CGRect(origin: .zero, size: .init(width: 20, height: 30)))
}
.fill(Color.primary) // You can delete this line of code as well! No issue!
.frame(width: 20, height: 30)
}
.padding()
.background(Color.secondary.cornerRadius(5))
}
}

How to get a horizontal picker for Swift UI?

Is there an existing solution to get a horizontal picker in Swift UI?
Example for Swift: https://github.com/akkyie/AKPickerView-Swift
I ended up solving this using a horizontal scrollview, tap gestures, and state to track the selection.
#State private var index
var body: some View {
        return ScrollView(.horizontal, showsIndicators: false) {
            HStack {
                ForEach(0..<self.items.count, id: \.self) { i in
                    Text("\(i)")
                        .foregroundColor(self.index == i ? .red : .black)
                        .frame(width: 20, height: 20)
                        .gesture(TapGesture().onEnded({ self.index = i }))
                }
            }
        }
        .frame(width: self.width, alignment: .leading)
}
You can use the Rotation Effect on a Picker and on the Picker's content. Make sure to rotate the content 90 degrees opposite from the picker or else the content will be sideways. If the picker is too big, you can manually set a height of the picker by using frame(height: _). In my case, I used frame(maxHeight: _). You might need to adjust the row indicators by using clipped() after the resize to stop them from flowing out of the picker.
I'm using images as an example but it should work with most if not all basic views.
Code:
Picker(selection: $data, label: Text("Data")) {
ForEach(dataArray, id: \.self) { imageName in
Image(imageName)
.resizable()
.scaledToFit()
.rotationEffect(Angle(degrees: 90))
}
}
.labelsHidden()
.rotationEffect(Angle(degrees: -90))
.frame(maxHeight: 100)
.clipped()