我是swiftui的初学者。我开始一个圣经应用程序作为一个初学者的项目。我创建了一个设置，并从该设置中，我想通过使用选择器来更改字体大小。我已经在网上搜索了4天了，我不知道我该怎么做。
问题1:我不知道如何根据选择器选择更新字体大小。有人说用。onchange，但我不知道怎么做。所以，我尝试使用切换案例方法，但仍然不知道如何更新文本。此外，我尝试使用自定义修饰符来替换。font(.footnote)之类的东西。但我仍然不知道如何更新它而且EnvironmentalObject一点帮助都没有。请指导我如何解决这个问题。
问题2:每次我播放画布时，选择器总是从默认索引开始选择，这是有意义的。但在实际的应用中，它是否总是在用户选择不同的索引后从默认索引开始还是我应该怎么做才能保持预选的索引。
下面是我的代码:import SwiftUI
struct Setting: View {
@State private var fontSizeIndex = 3
@State private var fontIndex = 1
var body: some View {
NavigationView {
ScrollView {
// Text Settings
Form {
// Font Size Picker
Section(header: Text("Text Settings")) {
Picker(selection: $fontSizeIndex, label: Text("Font Size"),
content: {
Text("Extra Small").tag(1)
Text("Small").tag(2)
Text("Medium").tag(3)
Text("Large").tag(4)
Text("Extra Large").tag(5)
})
// Font Picker
// I plan to make custom fonts if I know how to update my
// selection
Picker(selection: $fontIndex, label: Text("Font"), content: {
Text("Font1").tag(1)
Text("Font2").tag(2)
Text("Font3").tag(3)
Text("Font4").tag(4)
Text("Font5").tag(5)
Text("Font6").tag(6)
Text("Font7").tag(7)
})
}
}
.frame(height:280)
}
}
}
This is my Text or Scripture()在另一个视图
import SwiftUI
struct Scripture: View {
//@EnvironmentObject var fsc: FontSizeChanging
var body: some View {
ScrollView {
Text("Hih in Zeisu Khazih khang ciamtehna ahi hi. Amah in David tapa hi a, David in Abraham tapa ahi hi. 2 Abraham tapa Isaac, Isaac tapa Jacob, Jacob tapa Judah le a sanggam pasal teng ahi hi. 3 Judah in a zi Tamar tawh a neih a tapa Perez le Zerah, Perez tapa Hezron, Hezron tapa Ram, 4 Ram tapa Amminadab, Amminadab tapa Nahshon, Nahshon tapa Salmon, 5 Salmon in a zi Rahab tawh a neih a tapa Boaz, Boaz in a zi Ruth tawh a neih a tapa Obed, Obed tapa Jesse, 6 Jesse tapa kumpipa David ahi hi. David in Uriah zi tawh a neih a tapa Solomon, 7 Solomon tapa Rehoboam, Rehoboam tapa Abijah, Abijah tapa Asa, 8 Asa tapa Jehoshaphat, Jehoshaphat tapa Joram, Joram tapa Uzziah, 9 Uzziah tapa Jotham, Jotham tapa Ahaz, Ahaz tapa Hezekiah, 10 Hezekiah tapa Manasseh, Manasseh tapa Amon, Amon tapa Josiah ahi hi. 11 Jeconiah le a sanggam pasal tengin Babylon gamah sala a kipaipih madeuh in a suak Josiah tate ahi uh hi. 12 Babylon gama saltan khit ciangin Jeconiah in a neih a tapa Shealtiel, Shealtiel tapa Zerubbabel, 13 Zerubbabel tapa Abiud, Abiud tapa Eliakim, Eliakim tapa Azor, 14 Azor tapa Zadok, Zadok tapa Achim, Achim tapa Eliud, 15 Eliud tapa Eleazar, Eleazar tapa Matthan, Matthan tapa Jacob, 16 Jacob tapa Joseph hi a, Joseph in Khazih a kici Zeisu a hong suahna Mary pasal ahi hi. 17 Tua hi a, Abraham khang panin David khang ciang a vekin khang sawm le khang li, David khang panin Babylon gama saltang dinga a kimat hun ciang khang sawm le khang li, Babylon gama saltan hun pan Khazih khang ciang khang sawm le khang li mah ahi hi. 18 Zeisu Khazih a suahzia hih bang ahi hi. A nu Mary pen Joseph zi dingin zuthawl kipiasa hi a, a kiteenma un Kha Siangtho hangin gai hi ci in kithei hi. 19 A lawmpa Joseph in mi lungsim hoih hi a, a lawmnu Mary min daisak nuamlo ahih manin maksim dingin a ngaihsun hi.")
//.font(fsc.fontSize)
.foregroundColor(.primary)
//.font(Setting(fontSizeIndex: self.$fontSizeIndex))
.multilineTextAlignment(.leading) // test .center here
.lineSpacing(5)
.padding()
}
}
}
struct Scripture_Previews: PreviewProvider {
static var previews: some View {
Scripture()
}
}
下面应该可以工作。
我在屏幕右上方添加了一个齿轮图标，使设置和经文之间的导航更容易。这将允许您轻松地更改字体大小。
我的方法使用@AppStorage。这样可以保存数据，所以当用户启动应用程序时，他们的字体大小选择将保留。你可以在任何你需要编辑字体大小的地方使用它。
要更改字体大小，只需更新选择器中的.tag()中的值。我随机选了一组数字。这是您想要输入所需字体大小的地方。
import SwiftUI
struct Setting: View {
@State private var fontSizeIndex = 3
@State private var fontIndex = 1
@AppStorage("fontSize") var fontSize = 50
var body: some View {
NavigationView {
ScrollView {
// Text Settings
Form {
// Font Size Picker
Section(header: Text("Text Settings")) {
Picker(selection: $fontSize, label: Text("Font Size"),
content: {
Text("Extra Small").tag(10)
Text("Small").tag(15)
Text("Medium").tag(20)
Text("Large").tag(25)
Text("Extra Large").tag(50)
})
// Font Picker
// I plan to make custom fonts if I know how to update my
// selection
Picker(selection: $fontIndex, label: Text("Font"), content: {
Text("Font1").tag(1)
Text("Font2").tag(2)
Text("Font3").tag(3)
Text("Font4").tag(4)
Text("Font5").tag(5)
Text("Font6").tag(6)
Text("Font7").tag(7)
})
}
}
.frame(height:280)
}
}
}
}
struct Scripture: View {
//@EnvironmentObject var fsc: FontSizeChanging
@AppStorage("fontSize") var fontSize = 50
var body: some View {
NavigationView {
ScrollView {
Text("Hih in Zeisu Khazih khang ciamtehna ahi hi. Amah in David tapa hi a, David in Abraham tapa ahi hi. 2 Abraham tapa Isaac, Isaac tapa Jacob, Jacob tapa Judah le a sanggam pasal teng ahi hi. 3 Judah in a zi Tamar tawh a neih a tapa Perez le Zerah, Perez tapa Hezron, Hezron tapa Ram, 4 Ram tapa Amminadab, Amminadab tapa Nahshon, Nahshon tapa Salmon, 5 Salmon in a zi Rahab tawh a neih a tapa Boaz, Boaz in a zi Ruth tawh a neih a tapa Obed, Obed tapa Jesse, 6 Jesse tapa kumpipa David ahi hi. David in Uriah zi tawh a neih a tapa Solomon, 7 Solomon tapa Rehoboam, Rehoboam tapa Abijah, Abijah tapa Asa, 8 Asa tapa Jehoshaphat, Jehoshaphat tapa Joram, Joram tapa Uzziah, 9 Uzziah tapa Jotham, Jotham tapa Ahaz, Ahaz tapa Hezekiah, 10 Hezekiah tapa Manasseh, Manasseh tapa Amon, Amon tapa Josiah ahi hi. 11 Jeconiah le a sanggam pasal tengin Babylon gamah sala a kipaipih madeuh in a suak Josiah tate ahi uh hi. 12 Babylon gama saltan khit ciangin Jeconiah in a neih a tapa Shealtiel, Shealtiel tapa Zerubbabel, 13 Zerubbabel tapa Abiud, Abiud tapa Eliakim, Eliakim tapa Azor, 14 Azor tapa Zadok, Zadok tapa Achim, Achim tapa Eliud, 15 Eliud tapa Eleazar, Eleazar tapa Matthan, Matthan tapa Jacob, 16 Jacob tapa Joseph hi a, Joseph in Khazih a kici Zeisu a hong suahna Mary pasal ahi hi. 17 Tua hi a, Abraham khang panin David khang ciang a vekin khang sawm le khang li, David khang panin Babylon gama saltang dinga a kimat hun ciang khang sawm le khang li, Babylon gama saltan hun pan Khazih khang ciang khang sawm le khang li mah ahi hi. 18 Zeisu Khazih a suahzia hih bang ahi hi. A nu Mary pen Joseph zi dingin zuthawl kipiasa hi a, a kiteenma un Kha Siangtho hangin gai hi ci in kithei hi. 19 A lawmpa Joseph in mi lungsim hoih hi a, a lawmnu Mary min daisak nuamlo ahih manin maksim dingin a ngaihsun hi.")
//.font(fsc.fontSize)
.font(.system(size: CGFloat(fontSize)))
.foregroundColor(.primary)
//.font(Setting(fontSizeIndex: self.$fontSizeIndex))
.multilineTextAlignment(.leading) // test .center here
.lineSpacing(5)
.padding()
}
.toolbar {
ToolbarItem(placement: .navigationBarTrailing) {
HStack {
NavigationLink(destination: Setting(), label: {
Image(systemName: "gearshape")
})
}
}
}
}
}
}
struct Scripture_Previews: PreviewProvider {
static var previews: some View {
Scripture()
}
}