How to add a constructor to an existing class in Dart?
0
I'd like to make some convenience/factory constructors for a few common UI classes. For example, TextStyle:
enum Font {
AvenirNext,
AvenirNextCondensed
}
enum Weight {
Regular,
Medium,
DemiBold,
Bold
}
// Use:
// TextStyle(Fonts.AvenirNext, Weight.Medium, 20, Colors.white)
// Maybe it can be even shorter?
// TextStyle(AvenirNext, Medium, 20, Colors.black)
How to go about this in Dart?
class constructor dart
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
add a comment |
0
I'd like to make some convenience/factory constructors for a few common UI classes. For example, TextStyle:
enum Font {
AvenirNext,
AvenirNextCondensed
}
enum Weight {
Regular,
Medium,
DemiBold,
Bold
}
// Use:
// TextStyle(Fonts.AvenirNext, Weight.Medium, 20, Colors.white)
// Maybe it can be even shorter?
// TextStyle(AvenirNext, Medium, 20, Colors.black)
How to go about this in Dart?
class constructor dart
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
add a comment |
0
0
0
I'd like to make some convenience/factory constructors for a few common UI classes. For example, TextStyle:
enum Font {
AvenirNext,
AvenirNextCondensed
}
enum Weight {
Regular,
Medium,
DemiBold,
Bold
}
// Use:
// TextStyle(Fonts.AvenirNext, Weight.Medium, 20, Colors.white)
// Maybe it can be even shorter?
// TextStyle(AvenirNext, Medium, 20, Colors.black)
How to go about this in Dart?
class constructor dart
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
I'd like to make some convenience/factory constructors for a few common UI classes. For example, TextStyle:
enum Font {
AvenirNext,
AvenirNextCondensed
}
enum Weight {
Regular,
Medium,
DemiBold,
Bold
}
// Use:
// TextStyle(Fonts.AvenirNext, Weight.Medium, 20, Colors.white)
// Maybe it can be even shorter?
// TextStyle(AvenirNext, Medium, 20, Colors.black)
How to go about this in Dart?
class constructor dart
class constructor dart
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
asked Nov 25 '18 at 19:36
GoldenJoeGoldenJoe
3,78023058
3,78023058
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
1
How about extending TextStyle like below
class Font {
static const AvenirNext = 'AvenirNext';
static const AvenirNextCondensed = 'AvenirNextCondensed';
}
class Weight{
static const Regular = FontWeight.w400;
static const Medium = FontWeight.w500;
static const DemiBold = FontWeight.w700;
static const Bold = FontWeight.w900;
}
class CTextStyle extends TextStyle {
CTextStyle(String f, FontWeight w, num s, Color c)
: super(
fontFamily: f,
fontWeight: w,
fontSize: s.toDouble(),
color: c);
}
}
usage:
TextStyle myCustom = CTextStyle(Font.AvenirNext, Weight.Medium, 20, Colors.black);
edited Nov 26 '18 at 6:31
lrn
10.6k1324
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
2
Alternatively, don't even make a class, and just define top-level factory functions that create aTextStyleobject.
– lrn
Nov 26 '18 at 6:32
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }
– GoldenJoe
Nov 26 '18 at 19:15
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
How about extending TextStyle like below
class Font {
static const AvenirNext = 'AvenirNext';
static const AvenirNextCondensed = 'AvenirNextCondensed';
}
class Weight{
static const Regular = FontWeight.w400;
static const Medium = FontWeight.w500;
static const DemiBold = FontWeight.w700;
static const Bold = FontWeight.w900;
}
class CTextStyle extends TextStyle {
CTextStyle(String f, FontWeight w, num s, Color c)
: super(
fontFamily: f,
fontWeight: w,
fontSize: s.toDouble(),
color: c);
}
}
usage:
TextStyle myCustom = CTextStyle(Font.AvenirNext, Weight.Medium, 20, Colors.black);
edited Nov 26 '18 at 6:31
lrn
10.6k1324
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
2
Alternatively, don't even make a class, and just define top-level factory functions that create aTextStyleobject.
– lrn
Nov 26 '18 at 6:32
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }
– GoldenJoe
Nov 26 '18 at 19:15
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
add a comment |
1
How about extending TextStyle like below
class Font {
static const AvenirNext = 'AvenirNext';
static const AvenirNextCondensed = 'AvenirNextCondensed';
}
class Weight{
static const Regular = FontWeight.w400;
static const Medium = FontWeight.w500;
static const DemiBold = FontWeight.w700;
static const Bold = FontWeight.w900;
}
class CTextStyle extends TextStyle {
CTextStyle(String f, FontWeight w, num s, Color c)
: super(
fontFamily: f,
fontWeight: w,
fontSize: s.toDouble(),
color: c);
}
}
usage:
TextStyle myCustom = CTextStyle(Font.AvenirNext, Weight.Medium, 20, Colors.black);
edited Nov 26 '18 at 6:31
lrn
10.6k1324
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
2
Alternatively, don't even make a class, and just define top-level factory functions that create aTextStyleobject.
– lrn
Nov 26 '18 at 6:32
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }
– GoldenJoe
Nov 26 '18 at 19:15
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
add a comment |
1
1
1
How about extending TextStyle like below
class Font {
static const AvenirNext = 'AvenirNext';
static const AvenirNextCondensed = 'AvenirNextCondensed';
}
class Weight{
static const Regular = FontWeight.w400;
static const Medium = FontWeight.w500;
static const DemiBold = FontWeight.w700;
static const Bold = FontWeight.w900;
}
class CTextStyle extends TextStyle {
CTextStyle(String f, FontWeight w, num s, Color c)
: super(
fontFamily: f,
fontWeight: w,
fontSize: s.toDouble(),
color: c);
}
}
usage:
TextStyle myCustom = CTextStyle(Font.AvenirNext, Weight.Medium, 20, Colors.black);
edited Nov 26 '18 at 6:31
lrn
10.6k1324
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
How about extending TextStyle like below
class Font {
static const AvenirNext = 'AvenirNext';
static const AvenirNextCondensed = 'AvenirNextCondensed';
}
class Weight{
static const Regular = FontWeight.w400;
static const Medium = FontWeight.w500;
static const DemiBold = FontWeight.w700;
static const Bold = FontWeight.w900;
}
class CTextStyle extends TextStyle {
CTextStyle(String f, FontWeight w, num s, Color c)
: super(
fontFamily: f,
fontWeight: w,
fontSize: s.toDouble(),
color: c);
}
}
usage:
TextStyle myCustom = CTextStyle(Font.AvenirNext, Weight.Medium, 20, Colors.black);
edited Nov 26 '18 at 6:31
lrn
10.6k1324
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
edited Nov 26 '18 at 6:31
lrn
10.6k1324
edited Nov 26 '18 at 6:31
lrn
10.6k1324
edited Nov 26 '18 at 6:31
lrn
10.6k1324
10.6k1324
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
answered Nov 26 '18 at 1:47
Saed NabilSaed Nabil
1,25329
1,25329
2
Alternatively, don't even make a class, and just define top-level factory functions that create aTextStyleobject.
– lrn
Nov 26 '18 at 6:32
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }
– GoldenJoe
Nov 26 '18 at 19:15
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
add a comment |
2
Alternatively, don't even make a class, and just define top-level factory functions that create aTextStyleobject.
– lrn
Nov 26 '18 at 6:32
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }
– GoldenJoe
Nov 26 '18 at 19:15
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
2
2
Alternatively, don't even make a class, and just define top-level factory functions that create a
TextStyle object.– lrn
Nov 26 '18 at 6:32
Alternatively, don't even make a class, and just define top-level factory functions that create a
TextStyle object.– lrn
Nov 26 '18 at 6:32
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
Yes , great. I was trying to explain that we can not modify the class .we can only extend it.
– Saed Nabil
Nov 26 '18 at 7:57
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:
class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }– GoldenJoe
Nov 26 '18 at 19:15
This is great. For sake of academics, what if I kept the enums and constructed an argument list for the super constructor:
class TSExt extends TextStyle { //TSExt(Font font, Weight weight, double fontSize, Color color) : super(arguments); TSExt(Font font, Weight weight, double fontSize, Color color){ var args = { // ... }; super(args); } }– GoldenJoe
Nov 26 '18 at 19:15
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
@GoldenJow It seems a good idea , if you tested this approch please, let us know
– Saed Nabil
Nov 27 '18 at 9:52
add a comment |
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