I have a view model
public class ComplectationSubItemWrapper: MvxViewModel
{
public ComplectationSubItemWrapper ()
{
}
private ComplectationSubItem _complectationSubItem;
public ComplectationSubItem ComplectationSubItem
{
get { return _complectationSubItem; }
set { _complectationSubItem = value; RaisePropertyChanged(() => ComplectationSubItem); }
}
private bool _isSelected;
public bool IsSelected
{
get{ return _isSelected; }
set {
_isSelected = value;
RaisePropertyChanged(() => IsSelected);
}
}
}
How can I bind IsSelected property to TableCell's Selected?
I tried:
this.DelayBind(() => {
var set = this.CreateBindingSet<GenericPopoverCell, ComplectationSubItemWrapper>();
set.Bind(lblTitle).To(vm => vm.ComplectationSubItem.Title);
set.Bind(this).For(s => s.Selected).To(vm => vm.IsSelected);
set.Apply ();
});
but this is not working. It seems that Selected property is initialized before binding occures. SelectionChangedCommand is not suitable because I need AllowsMultipleSelection.
Related
How do I handle multiple inverse relations pointing to the same active record?
For example:
class Bicycle extends ActiveRecord {
public function getFrontWheel() {
return $this
->hasOne(Wheel::class, ['id' => 'front_wheel_id'])
->inverseOf('bicycles');
}
public function getRearWheel() {
return $this
->hasOne(Wheel::class, ['id' => 'rear_wheel_id'])
->inverseOf('bicycles');
}
}
class Wheel extends ActiveRecord {
public function getBicycles() {
return $this
->hasMany(Bicycle::class, ['???' => 'id'])
->inverseOf('??????');
}
}
What can I do here? I critically need the inverse relations.
Here is my own solution.
Key points:
It all boils down to proper naming.
Inverse relations are bijective! In other words, every relation always has to have its own unique mirror relation on the other end.
class Bicycle extends ActiveRecord {
public function getFrontWheel() {
return $this
->hasOne(Wheel::class, ['id' => 'front_wheel_id'])
->inverseOf('frontWheelBicycles');
}
public function getRearWheel() {
return $this
->hasOne(Wheel::class, ['id' => 'rear_wheel_id'])
->inverseOf('rearWheelBicycles');
}
}
class Wheel extends ActiveRecord {
public function getFrontWheelBicycles() {
return $this
->hasMany(Bicycle::class, ['front_wheel_id' => 'id'])
->inverseOf('frontWheel');
}
public function getRearWheelBicycles() {
return $this
->hasMany(Bicycle::class, ['rear_wheel_id' => 'id'])
->inverseOf('rearWheel');
}
}
i would suggest to do the following:
create two new classes:
class FrontWheel extends Wheel {
class RearWheel extends Wheel {
in new classes you can set easily the relation.
How to instantiate the correct class? There is a method in ActiveRecord instantiate() where you can write your logic which wheel class need to be created.
class Wheel extends ActiveRecord {
...
public static function instantiate ( $row ) {
if($row['type'] === 'RearWheel') {
return new RealWheel();
}
...
}
full code:
class Bicycle extends ActiveRecord
{
public function getFrontWheel()
{
return $this
->hasOne(Wheel::class, ['id' => 'front_wheel_id'])
->inverseOf('bicycles');
}
public function getRearWheel()
{
return $this
->hasOne(Wheel::class, ['id' => 'rear_wheel_id'])
->inverseOf('bicycles');
}
}
abstract class Wheel extends ActiveRecord
{
public static function instantiate($row)
{
if ($row['type'] === 'RearWheel') {
return new RealWheel();
}
if ($row['type'] === 'FrontWheel') {
return new FrontWheel();
}
throw new InvalidConfigException();
}
abstract public function getBicycles();
}
class RealWheel extends Wheel
{
public function getBicycles()
{
return $this
->hasMany(Bicycle::class, ['rear_wheel_id' => 'id'])
->inverseOf('rearWheel');
}
}
class FrontWheel extends Wheel
{
public function getBicycles()
{
return $this
->hasMany(Bicycle::class, ['front_wheel_id' => 'id'])
->inverseOf('frontWheel');
}
}
How do I declare the method getYellowCycle() so that the variable game can access it? getYellowCycle is a method that's in another method called newGame(), that's in a class called model.game.
Here is where the method should be called.
let game = model.Game.newGame();
expect(game.getYellowCycle().getX()).to.equal(50);
Here is the class model.game
model.Game = class {
newGame() {
}
};
getYellowCycle() should go in newGame()
Something like this:
const model = {};
model.Game = class {
newGame() {
return {
getYellowCycle() {
return {
getX() {
console.log("In getX");
return 50;
}
};
}
};
}
};
const game = (new model.Game()).newGame();
console.log(game.getYellowCycle().getX());
I'm trying to use Topshelf Framework to create a windows service. But when i try to start the service, there is this exception :
" The service failed to start... System.Service.Process.TimeoutException : the waiting period has expired and the operation has not been completed"
This is my code :
public class MyService : ServiceControl
{
private System.Timers.Timer _timer;
public void MyService()
{
_timer = new System.Timers.Timer(10);
_timer.AutoReset = false;
_timer.Elapsed += new ElapsedEventHandler(TimerOnElapsed);
}
private void TimerOnElapsed(object source, ElapsedEventArgs e)
{
//all the operation to do at the startup
}
public bool Start(HostControl hostControl)
{
_timer.Start();
return true;
}
public bool Stop(HostControl hostControl)
{
_timer.Stop();
return true;
}
}
Thanks for any help :)
There are several issues I notice:
The current code would make the timer fire only once (you have AutoReset = false)
with TopShelf, the MyService class should look like this:
using System.Timers;
using Topshelf;
namespace TopShelfTestService
{
public class MyService
{
private System.Timers.Timer _timer;
public MyService()
{
_timer = new System.Timers.Timer(10);
_timer.AutoReset = true;
_timer.Elapsed += new ElapsedEventHandler(TimerOnElapsed);
}
private void TimerOnElapsed(object source, ElapsedEventArgs e)
{
//all the operation to do at the startup
}
public bool Start(HostControl hostControl)
{
_timer.Start();
return true;
}
public bool Stop(HostControl hostControl)
{
_timer.Stop();
return true;
}
}
}
and the console app/ Program.cs will look like so:
using Topshelf;
namespace TopShelfTestService
{
class Program
{
static void Main(string[] args)
{
HostFactory.Run(x =>
{
x.Service<MyService>(s =>
{
s.ConstructUsing(name => new MyService());
s.WhenStarted((tc, hostControl) => tc.Start(hostControl));
s.WhenStopped((tc, hostControl) => tc.Stop(hostControl));
});
x.RunAsLocalSystem();
x.SetDescription("Sample Topshelf Host"); //7
x.SetDisplayName("Test Service with TopShelf"); //8
x.SetServiceName("TopShelfTestService");
});
}
}
}
I tried to bind a widget to a viewmodel property but I'm getting an exception
MvxBind:Warning: 14.76 Failed to create target binding for binding Signature for Order.ClientSignature
[0:] MvxBind:Warning: 14.76 Failed to create target binding for binding Signature for Order.ClientSignature
04-26 21:02:15.380 I/mono-stdout(32490): MvxBind:Warning: 14.76 Failed to create target binding for binding Signature for Order.ClientSignature
The widget is courtesy of Al taiar
The axml is
<SignatureWidget
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="#+id/signatureWidget1"
android:layout_marginRight="5dp"
android:layout_marginLeft="5dp"
android:layout_marginBottom="5dp"
local:MvxBind="Signature Order.ClientSignature" />
The code for the view is
using Android.Content;
using Android.Graphics;
using Android.Util;
using Android.Views;
using Core.Models;
using System;
public class SignatureWidget
: View
{
#region Implementation
private Bitmap _bitmap;
private Canvas _canvas;
private readonly Path _path;
private readonly Paint _bitmapPaint;
private readonly Paint _paint;
private float _mX, _mY;
private const float TouchTolerance = 4;
#endregion
public Signature Signature;
public event EventHandler SignatureChanged;
public SignatureWidget(Context context, IAttributeSet attrs)
: base(context, attrs)
{
Signature = new Signature();
_path = new Path();
_bitmapPaint = new Paint(PaintFlags.Dither);
_paint = new Paint
{
AntiAlias = true,
Dither = true,
Color = Color.Argb(250, 00, 0, 0)
};
_paint.SetStyle(Paint.Style.Stroke);
_paint.StrokeJoin = Paint.Join.Round;
_paint.StrokeCap = Paint.Cap.Round;
_paint.StrokeWidth = 5;
}
protected override void OnSizeChanged(int w, int h, int oldw, int oldh)
{
base.OnSizeChanged(w, h, oldw, oldh);
_bitmap = Bitmap.CreateBitmap(w, (h > 0 ? h : ((View)this.Parent).Height), Bitmap.Config.Argb8888);
_canvas = new Canvas(_bitmap);
}
protected override void OnDraw(Canvas canvas)
{
canvas.DrawColor(Color.White);
canvas.DrawBitmap(_bitmap, 0, 0, _bitmapPaint);
canvas.DrawPath(_path, _paint);
}
private void TouchStart(float x, float y)
{
_path.Reset();
_path.MoveTo(x, y);
_mX = x;
_mY = y;
Signature.AddPoint(SignatureState.Start, (int)x, (int)y);
}
private void TouchMove(float x, float y)
{
float dx = Math.Abs(x - _mX);
float dy = Math.Abs(y - _mY);
if (dx >= TouchTolerance || dy >= TouchTolerance)
{
_path.QuadTo(_mX, _mY, (x + _mX) / 2, (y + _mY) / 2);
Signature.AddPoint(SignatureState.Move, (int)x, (int)y);
_mX = x;
_mY = y;
}
}
private void TouchUp()
{
if (!_path.IsEmpty)
{
_path.LineTo(_mX, _mY);
_canvas.DrawPath(_path, _paint);
}
else
{
_canvas.DrawPoint(_mX, _mY, _paint);
}
Signature.AddPoint(SignatureState.End, (int)_mX, (int)_mY);
_path.Reset();
}
public override bool OnTouchEvent(MotionEvent e)
{
var x = e.GetX();
var y = e.GetY();
switch (e.Action)
{
case MotionEventActions.Down:
TouchStart(x, y);
Invalidate();
break;
case MotionEventActions.Move:
TouchMove(x, y);
Invalidate();
break;
case MotionEventActions.Up:
TouchUp();
Invalidate();
break;
}
RaiseSignatureChangedEvent();
return true;
}
public void ClearCanvas()
{
_canvas.DrawColor(Color.White);
Invalidate();
}
public Bitmap CanvasBitmap()
{
return _bitmap;
}
public void Clear()
{
ClearCanvas();
Signature.Clear();
RaiseSignatureChangedEvent();
}
private void RaiseSignatureChangedEvent()
{
var handler = SignatureChanged;
if (handler != null)
handler(this, EventArgs.Empty);
}
}
And the code for the model is
public class Signature
{
private List<Point> _currentPath;
private readonly List<List<Point>> _paths;
public event EventHandler PointAdded;
public Signature()
{
_currentPath = new List<Point>();
_paths = new List<List<Point>>();
}
public IReadOnlyList<IReadOnlyList<Point>> Paths
{
get { return _paths; }
}
public Point LastPoint()
{
if (_currentPath != null && _currentPath.Count > 0)
{
return _currentPath.Last();
}
return new Point(0, 0);
}
public void Clear()
{
_paths.Clear();
_currentPath.Clear();
}
public void AddPoint(SignatureState state, int x, int y)
{
if (state == SignatureState.Start)
{
_currentPath = new List<Point>();
}
if (x != 0 && y != 0)
{
_currentPath.Add(new Point(x, y));
}
if (state == SignatureState.End)
{
if (_currentPath != null)
{
_paths.Add(_currentPath);
}
}
RaisePointAddedEvent();
}
public int Length
{
get { return _paths.Count; }
}
protected void RaisePointAddedEvent()
{
if (PointAdded != null)
PointAdded(this, EventArgs.Empty);
}
}
I will need two-way binding for this widget. Anyone care to help???
I will also need to add a "Clear" text as an overlay on the view. Clicking this text will trigger a command to clear the widget. Any clue how to do this?
P.S:
I've followed the informative post and I still cannot get it to work. I've added the following.
public class SignatureWidgetSignatureTargetBinding
: MvxPropertyInfoTargetBinding<SignatureWidget>
{
public SignatureWidgetSignatureTargetBinding(object target, PropertyInfo targetPropertyInfo)
: base(target, targetPropertyInfo)
{
View.SignatureChanged += OnSignatureChanged;
}
public override MvxBindingMode DefaultMode
{
get { return MvxBindingMode.TwoWay; }
}
private void OnSignatureChanged(object sender, EventArgs eventArgs)
{
FireValueChanged(View.Signature);
}
protected override void Dispose(bool isDisposing)
{
base.Dispose(isDisposing);
if (isDisposing)
{
View.SignatureChanged -= OnSignatureChanged;
}
}
}
and registered using
registry.RegisterFactory(new MvxSimplePropertyInfoTargetBindingFactory(typeof(SignatureWidgetSignatureTargetBinding), typeof(SignatureWidget), "Signature"));
MvvmCross will automatically bind a View property if you model it using the format:
public foo Bar {
get { /* ... your code ... */ }
set { /* ... your code ... */ }
}
public event EventHandler BarChanged;
Based on this I think your problem is that you are trying to use a field - public Signature Signature; - try using a property instead.
I think the binding mode you are looking for is also the unusual OneWayToSource instead of TwoWay
Is it somehow possible to bind view properties to ICommand.CanExecute?
I'd for example like to be able to do something like this in a touch view:
this
.CreateBinding(SignInWithFacebookButton)
.For(b => b.Enabled)
.To((SignInViewModel vm) => vm.SignInWithFacebookCommand.CanExecute)
.Apply();
I've already read How to use CanExecute with Mvvmcross, but unfortunately it skips the questions and instead just proposes another implementation.
One way of doing this is to use your own custom button inheriting from UIButton.
For Android, I've got an implementation of this to hand - it is:
public class FullButton : Button
{
protected FullButton(IntPtr javaReference, JniHandleOwnership transfer) : base(javaReference, transfer)
{
Click += OnClick;
}
public FullButton(Context context) : base(context)
{
Click += OnClick;
}
public FullButton(Context context, IAttributeSet attrs) : base(context, attrs)
{
Click += OnClick;
}
public FullButton(Context context, IAttributeSet attrs, int defStyle) : base(context, attrs, defStyle)
{
Click += OnClick;
}
private IDisposable _subscription;
private object _commandParameter;
public object CommandParameter
{
get { return _commandParameter; }
set
{
_commandParameter = value;
UpdateEnabled();
}
}
private ICommand _command;
public ICommand Command
{
get { return _command; }
set
{
if (_subscription != null)
{
_subscription.Dispose();
_subscription = null;
}
_command = value;
if (_command != null)
{
var cec = typeof (ICommand).GetEvent("CanExecuteChanged");
_subscription = cec.WeakSubscribe(_command, (s, e) =>
{
UpdateEnabled();
});
}
UpdateEnabled();
}
}
private void OnClick(object sender, EventArgs eventArgs)
{
if (Command == null)
return;
if (Command.CanExecute(CommandParameter))
Command.Execute(CommandParameter);
}
private void UpdateEnabled()
{
Enabled = ShouldBeEnabled();
}
private bool ShouldBeEnabled()
{
if (_command == null)
return false;
return _command.CanExecute(CommandParameter);
}
}
and this can be bound as:
<FullButton
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Show Detail"
local:MvxBind="Command ShowDetailCommand; CommandParameter CurrentItem" />
For iOS, I'd expect the same type of technique to work... inheriting from a UIButton and using TouchUpInside instead of Click - but I'm afraid I don't have this code with me at the moment.