This change gets rid of the event.Queue interface by replacing it with
input.Source values. Source provides the interface to Router necessary
to implement interface widgets.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We're about to replace the interface Queue with a concrete input.Source.
This change renames the field accordingly.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
In the early days of Gio, FrameEvent was part of package app. It was
moved to package system to enable layout.NewContext be a convenient
short-hand for constructing a layout.
However, it seems the better design to leave FrameEvent (and Insets) in
package app, and move layout.NewContext there as well. More importantly,
the move allows us to replace the event.Queue interface with a concrete
type.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The unit.Value is a struct and thus more inconvenient to use than its
underlying float32 type. In addition, most uses don't need a general
value, but rather a specific unit given by the context. This change
replaces unit.Value with two float32 units, Dp and Sp. It also changes
variables and parameters of unit.Value to a specific unit type matching
the context. That is, unit.Dp everywhere except for text sizes which are
in Sp.
Switching to typed float32s has multiple advantages
- They can be constants:
const touchSlop = unit.Dp(16)
- Casting untyped constants is no longer necessary:
insets := layout.UniformInset(16)
- Calculation with values is natural:
func (s ScrollbarStyle) Width() unit.Dp {
return s.Indicator.MinorWidth + s.Track.MinorPadding + s.Track.MinorPadding
}
The main API change is that calls to gtx.Px must be replaced with either
gtx.Dp or gtx.Sp depending on the unit.
Idea by Christophe Meessen.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
op.Offset is a convenience function most often used by layouts. Layouts
usually operate in integer coordinates, and the float32 version of op.Offset
needlessly force conversions from int to float32. This change makes op.Offset
take integer coordinates, to better match its intended use.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Currently every user needs to manually adjust for system insets.
This is rather verbose and most don't need to deviate from this behavior.
To disable the automatic adjustment, use:
e.Insets = system.Insets{}
ctx := layout.NewContext(ops, e)
Signed-off-by: Egon Elbre <egonelbre@gmail.com>
An interface for scaling dp and sp is overkill, at least for all
current uses. Make it a concrete struct type, and rename it to the
shorter and more precise Metric.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Then, make layout.Context.Now a field, copied from FrameEvent.Now.
API change:
gofmt -r 'gtx.Now() -> gtx.Now'
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The layout package imports io/system anyway, so depending on
FrameEvent does not introduce new dependencies.
API change. Use gofmt to adjust your code:
gofmt -r 'layout.NewContext(a, b, c, d) -> layout.NewContext(a, e)'
Signed-off-by: Elias Naur <mail@eliasnaur.com>
This adds a simple method that returns a copy of the Context
with no event queue. Widgets laid out with this Context will
never receive events, and can check whether the event queue
is nil as a hint for whether or not to draw themselves as
disabled.
Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
Change the definition of Widget from the implicit
type Widget func()
to the explicit functional
type Widget func(gtx layout.Context) layout.Dimensions
The advantages are numerous:
- Clearer connection between the incoming context and the output dimensions.
- Returning the Dimensions are impossible to omit.
- Contexts passed by value, so its fields can be exported
and freely mutated by the program.
The only disadvantage is the longer function literals and the many "returns".
What tipped the scales in favour of the explicit Widget variant is that type
aliases can dramatically shorten the literals:
type (
C = layout.Context
D = layout.Dimensions
)
widget := func(gtx C) D {
...
}
Note that the aliases are not part of the Gio API and it is up to each user
whether they want to use them.
Finally the Go proposal for lightweight function literals,
https://github.com/golang/go/issues/21498, may remove the disadvantage
completely in future.
Context becomes a plain struct with only public fields, and its Reset is
replaced by a NewContext convenience constructor.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Instead of
type Contraints struct {
Width, Height Constraint
}
use
type Constraints struct {
Min, Max image.Point
}
which leads to simpler use. For example, the Min method is trivally replaced by
the field, and the RigidConstraints constructor is no longer a net win.
API Change. Rewrites:
gofmt -r 'gtx.Constraints.Min() -> gtx.Constraints.Min'
gofmt -r 'gtx.Constraints.Width.Min -> gtx.Constraints.Min.X'
gofmt -r 'gtx.Constraints.Height.Min -> gtx.Constraints.Min.Y'
gofmt -r 'gtx.Constraints.Height.Max -> gtx.Constraints.Max.Y'
gofmt -r 'gtx.Constraints.Width.Max -> gtx.Constraints.Max.X'
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Key had an unfortunate association with keyboard input.
This is an API change. The following rewrites were run to fixup
Gio code:
$ gofmt -r 'pointer.InputOp{Key:a} -> pointer.InputOp{Tag:a}' -w .
$ gofmt -r 'pointer.InputOp{Key:a, Grab:b} -> pointer.InputOp{Tag:a, Grab:b}' -w .
$ gofmt -r 'key.InputOp{Key:a} -> key.InputOp{Tag:a}' -w .
$ gofmt -r 'key.InputOp{Key:a, Focus:b} -> key.InputOp{Tag:a, Focus:b}' -w .
$ gofmt -r 'event.Key -> event.Tag' -w .
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We're about to reduce the scope of the Window.Queue by moving it
to FrameEvent. As a consequence, Context can no longer rely on a
Queue constant over its lifetime.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
While here, unexport the Queue and Config fields. The NewContext
cosntructor is shorter, and there is no reason to expose the fields
to accidental mutation.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur