container.dart
3.89 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
/*
* Copyright (C) 2017, David PHAM-VAN <dev.nfet.net@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// ignore_for_file: omit_local_variable_types
part of widget;
class DecoratedBox extends SingleChildWidget {
DecoratedBox(
{@required this.decoration,
this.position = DecorationPosition.background,
Widget child})
: assert(decoration != null),
assert(position != null),
super(child: child);
/// What decoration to paint.
final BoxDecoration decoration;
/// Whether to paint the box decoration behind or in front of the child.
final DecorationPosition position;
@override
void paint(Context context) {
super.paint(context);
if (position == DecorationPosition.background) {
decoration.paint(context, box);
}
paintChild(context);
if (position == DecorationPosition.foreground) {
decoration.paint(context, box);
}
}
}
class Container extends StatelessWidget {
Container({
this.alignment,
this.padding,
PdfColor color,
BoxDecoration decoration,
this.foregroundDecoration,
double width,
double height,
BoxConstraints constraints,
this.margin,
this.transform,
this.child,
}) : assert(
color == null || decoration == null,
'Cannot provide both a color and a decoration\n'
'The color argument is just a shorthand for "decoration: new BoxDecoration(color: color)".'),
decoration =
decoration ?? (color != null ? BoxDecoration(color: color) : null),
constraints = (width != null || height != null)
? constraints?.tighten(width: width, height: height) ??
BoxConstraints.tightFor(width: width, height: height)
: constraints,
super();
final Widget child;
final Alignment alignment;
final EdgeInsets padding;
/// The decoration to paint behind the [child].
final BoxDecoration decoration;
/// The decoration to paint in front of the [child].
final BoxDecoration foregroundDecoration;
/// Additional constraints to apply to the child.
final BoxConstraints constraints;
/// Empty space to surround the [decoration] and [child].
final EdgeInsets margin;
/// The transformation matrix to apply before painting the container.
final Matrix4 transform;
@override
Widget build(Context context) {
Widget current = child;
if (child == null && (constraints == null || !constraints.isTight)) {
current = LimitedBox(
maxWidth: 0,
maxHeight: 0,
child: ConstrainedBox(constraints: const BoxConstraints.expand()));
}
if (alignment != null) {
current = Align(alignment: alignment, child: current);
}
if (padding != null) {
current = Padding(padding: padding, child: current);
}
if (decoration != null) {
current = DecoratedBox(decoration: decoration, child: current);
}
if (foregroundDecoration != null) {
current = DecoratedBox(
decoration: foregroundDecoration,
position: DecorationPosition.foreground,
child: current);
}
if (constraints != null) {
current = ConstrainedBox(constraints: constraints, child: current);
}
if (margin != null) {
current = Padding(padding: margin, child: current);
}
if (transform != null) {
current = Transform(transform: transform, child: current);
}
return current;
}
}