mirror of
https://git.sr.ht/~eliasnaur/gio
synced 2026-07-01 15:45:38 +00:00
Egon Elbre
e1248651c8
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>
93 lines
2.0 KiB
Go
93 lines
2.0 KiB
Go
// SPDX-License-Identifier: Unlicense OR MIT
|
|
|
|
package layout
|
|
|
|
import (
|
|
"time"
|
|
|
|
"gioui.org/f32"
|
|
"gioui.org/io/event"
|
|
"gioui.org/io/system"
|
|
"gioui.org/op"
|
|
"gioui.org/unit"
|
|
)
|
|
|
|
// Context carries the state needed by almost all layouts and widgets.
|
|
// A zero value Context never returns events, map units to pixels
|
|
// with a scale of 1.0, and returns the zero time from Now.
|
|
type Context struct {
|
|
// Constraints track the constraints for the active widget or
|
|
// layout.
|
|
Constraints Constraints
|
|
|
|
Metric unit.Metric
|
|
// By convention, a nil Queue is a signal to widgets to draw themselves
|
|
// in a disabled state.
|
|
Queue event.Queue
|
|
// Now is the animation time.
|
|
Now time.Time
|
|
|
|
*op.Ops
|
|
}
|
|
|
|
// NewContext is a shorthand for
|
|
//
|
|
// Context{
|
|
// Ops: ops,
|
|
// Now: e.Now,
|
|
// Queue: e.Queue,
|
|
// Config: e.Config,
|
|
// Constraints: Exact(e.Size),
|
|
// }
|
|
//
|
|
// NewContext calls ops.Reset and adjusts ops for e.Insets.
|
|
func NewContext(ops *op.Ops, e system.FrameEvent) Context {
|
|
ops.Reset()
|
|
|
|
size := e.Size
|
|
|
|
if e.Insets != (system.Insets{}) {
|
|
left := e.Metric.Px(e.Insets.Left)
|
|
top := e.Metric.Px(e.Insets.Top)
|
|
op.Offset(f32.Point{
|
|
X: float32(left),
|
|
Y: float32(top),
|
|
}).Add(ops)
|
|
|
|
size.X -= left + e.Metric.Px(e.Insets.Right)
|
|
size.Y -= top + e.Metric.Px(e.Insets.Bottom)
|
|
}
|
|
|
|
return Context{
|
|
Ops: ops,
|
|
Now: e.Now,
|
|
Queue: e.Queue,
|
|
Metric: e.Metric,
|
|
Constraints: Exact(size),
|
|
}
|
|
}
|
|
|
|
// Px maps the value to pixels.
|
|
func (c Context) Px(v unit.Value) int {
|
|
return c.Metric.Px(v)
|
|
}
|
|
|
|
// Events returns the events available for the key. If no
|
|
// queue is configured, Events returns nil.
|
|
func (c Context) Events(k event.Tag) []event.Event {
|
|
if c.Queue == nil {
|
|
return nil
|
|
}
|
|
return c.Queue.Events(k)
|
|
}
|
|
|
|
// Disabled returns a copy of this context with a nil Queue,
|
|
// blocking events to widgets using it.
|
|
//
|
|
// By convention, a nil Queue is a signal to widgets to draw themselves
|
|
// in a disabled state.
|
|
func (c Context) Disabled() Context {
|
|
c.Queue = nil
|
|
return c
|
|
}
|