I'm experiencing strange behaviour in binding of simple EditText controls within one viewmodel. For some of the properties, the binding works, for others it does not while i cannot discover any difference in the way the code is written (both in cs and axml files). What could cause such baheviour ? How can one debug binding triggering problems ? Code snippets of two properties below. The first one works, the second doesn't...
private string _firstName;
public string FirstName
{
get { return _firstName; }
set
{
_firstName = value; RaisePropertyChanged(() => FirstName);
}
}
private string _installer;
public string Installer
{
get { return _installer; }
set
{
_installer = value; RaisePropertyChanged(() => Installer);
}
}
axml :
<EditText
android:id="#+id/firstname"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="3"
android:textSize="20sp"
android:hint="First Name"
local:MvxBind="Text FirstName" />
<EditText
android:id="#+id/installer"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="20sp"
android:hint="Installer"
Mvx.MvxBind="Text Installer"
android:layout_weight="1"/>
Related
I need to add pictures to dropdown items.
In the dropdown I need to see the icon first and the text below. But for some reason, I can't see images, though I see the empty place instead.
My project is Xamarin.Android with MVVMCross. I'm missing something, maybe I need some plugins?
I have MypageView.axml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<include
layout="#layout/toolbar" />
<TextView
android:id="#+id/city"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:layout_marginBottom="8dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:textSize="12sp"
android:layout_below="#id/toolbar"
local:MvxBind="Text Strings[CityTextView]" />
<MvxSpinner
android:id="#+id/select_city"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:layout_marginBottom="24dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:spinnerMode="dropdown"
android:layout_below="#id/city"
local:MvxItemTemplate="#layout/item_city"
local:MvxDropDownItemTemplate="#layout/item_city"
local:MvxBind="ItemsSource Cities; SelectedItem SelectedCity" />
And item_city.axml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="10dp">
<ImageView
android:id="#+id/cityImage"
android:layout_width="35dp"
android:layout_height="20dp"
android:layout_marginLeft="16dp"
android:scaleType="fitXY"
local:MvxBind="DrawableName Name, Converter=IconsConverter" /> />
<TextView
android:id="#+id/cityName"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:layout_marginLeft="8dp"
android:layout_toRightOf="#id/cityImage"
android:textSize="16sp"
local:MvxBind="Text Name" />
</RelativeLayout>
In the Core, I have City.cs:
namespace My.cities.Core.Models
{
public class City
{
public City(string Id, string Name, string Flag)
{
this.Id = Id;
this.Name = Name;
this.Flag = Flag;
}
public string Id { get; set; }
public string Name { get; set; }
public string Flag { get; set; }
}
}
And MypageViewModel.cs:
using MvvmCross.Core.ViewModels;
using System.Collections.Generic;
using My.cities.Core.Models;
namespace My.cities.Core.ViewModels
{
public class MypageViewModel : BaseViewModel
{
private City _selectedCity;
private List<City> _cities = new List<City>()
{
new City("1", "London", "England")
new City("2", "Paris", "France")
};
public List<City> Cities
{
get { return _cities; }
}
public City SelectedCity
{
get
{
return _selectedCity;
}
set
{
_selectedCity = value;
RaisePropertyChanged(() => SelectedCity);
}
}
}
}
So I add the converter to MypageView.cs:
using Android.App;
using MvvmCross.Platform.Converters;
using System;
using System.Globalization;
namespace My.cities.Droid.Views
{ [Activity]
class MypageView : BaseView
{
protected override int LayoutResource => Resource.Layout.MypageView;
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
}
public static class CrossDeviceInfoHelper
{
public static string GetLocalImageUrlByPlatform(string name)
{
return CrossDeviceInfo.Current.Platform == Platform.Android ? $"#drawable/{name}" : name;
}
}
public class IconsConverter : MvxValueConverter<string, string>
{
protected override string Convert(string value, Type targetType, object parameter, CultureInfo culture)
{
if (value == "London")
return CrossDeviceInfoHelper.GetLocalImageUrlByPlatform("england");
if (value == "Paris")
return CrossDeviceInfoHelper.GetLocalImageUrlByPlatform("france");
}
}
Images England.png and France.png live here: My.sities.Droid\Resources\drawable-hdpi, My.sities.Droid\Resources\drawable-mdpi, and etc.
The build is successful, but I can't see my images, only empty rectangles. Why?
UPD.
I installed Xam.Plugin.DeviceInfo and changed my code. But I still can't see icons.
In debug it says:
[0:] MvxBind:Warning: 36,05 Value '' could not be parsed as a valid string identifier
[0:] MvxBind:Warning: 36,06 Value '' could not be parsed as a valid string identifier
[0:] MvxBind:Warning: 36,06 Value 'London' was not a known drawable name
[0:] MvxBind:Warning: 36,08 Value 'Paris' was not a known drawable name
UPD2.
Also, I tried to do it this way:
public class IconsConverter : MvxValueConverter<string, int>
{
protected override int Convert(string value, Type targetType,
object parameter, CultureInfo culture)
{
switch (value)
{
case "London":
return Resource.Mipmap.England;
case "Paris":
return Resource.Mipmap.France;
}
}
}
But the error is the same:
[0:] MvxBind:Warning: 9,54 Value '' could not be parsed as a valid string identifier
[0:] MvxBind:Warning: 9,63 Value '' could not be parsed as a valid string identifier
[0:] MvxBind:Warning: 9,64 Value 'London' was not a known drawable name
[0:] MvxBind:Warning: 9,65 Value 'Paris' was not a known drawable name
I think you are lacking the android:scaleType in your ImageView. Try using android:scaleType="fitXY".
If it is not that, try using the DrawableName binding instead of DrawableId and it's better because you can use a converter in your PCL making it cross-platform with Xam.Plugin.DeviceInfo and a helper method like this one:
public static class CrossDeviceInfoHelper
{
public static string GetLocalImageUrlByPlatform(string name)
{
// Assuming we are working with Android and iOS
return CrossDeviceInfo.Current.Platform == Platform.Android ? $"#drawable/{name}" : name;
}
}
So you'll endup with a Converter like this one:
public class StringToIntValueConverter : MvxValueConverter<string, string>
{
protected override string Convert(string value, Type targetType, object parameter, CultureInfo culture)
{
if (value == "London")
return CrossDeviceInfoHelper.GetLocalImageUrlByPlatform("england");
if (value == "Paris")
return CrossDeviceInfoHelper.GetLocalImageUrlByPlatform("france");
}
}
Also if I were you I'll add an enum or something that tells you the country in your City class so that you don't have to compare strings in the converter and you could also have a Dictionary in your converter that has which city goes with which country image so that you can just call CrossDeviceInfoHelper.GetLocalImageUrlByPlatform(myDictionary[value]); and therefore not using ifs
The binding expression DrawableName Name Converter=IconsConverter is wrong. You are missing a comma:
DrawableName Name, Converter=IconsConverter
Alternatively you can write it like:
DrawableName Icons(Name)
you can see gridview in the image which is not wrapping whole nestedscrollview Guys please help me I am stucked in this code, I need a collapsing toolbar layout and I succeed too but the gridview inside the nested scrollview is not wrapping total space of nestedscrollview, I tried many ways but failed.
This is the xml which is helping me to collapse toolbar and where I am getting gridview issues,
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.patelsanket.myalbum.activities.AlbumImageDisplayActivity">
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar"
android:layout_width="match_parent"
android:layout_height="#dimen/app_bar_height"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<ImageView
android:id="#+id/headerImage1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:contentDescription="#string/shows_header_image"
android:fitsSystemWindows="true"
android:scaleType="fitXY"
android:src="#drawable/cod" />
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<GridView
android:id="#+id/album_image_grid_view"
android:layout_width="match_parent"
android:layout_height="550dip"
android:choiceMode="multipleChoice"
android:horizontalSpacing="0.5dp"
android:numColumns="2"
android:paddingBottom="20dip" />
</RelativeLayout>
</android.support.v4.widget.NestedScrollView>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/fab_margin"
android:src="#drawable/ic_add"
app:backgroundTint="#009688"
app:layout_anchor="#id/app_bar"
app:layout_anchorGravity="bottom|end|right" />
</android.support.design.widget.CoordinatorLayout>
Use RecyclerView with GridLayoutManager. As Recycler view is compitable with Collasping bartoolbar too...
I hope it helps..
After searching a lot I found that using expandable gridview it can be solved. I used the following class and it is working fine.
This is a custom implementation of the native GridView ,
Here we override the functionality pertaining to GridView's height.
This implementation does away with a fixed Height GridView , rather
the height of the GridView expands depending upon the number of child elements added into it.
public class ExpandableGridView extends GridView{
boolean expanded = false;
public boolean isExpanded()
{
return expanded;
}
public ExpandableGridView(Context context)
{
super(context);
}
public ExpandableGridView(Context context, AttributeSet attrs)
{
super(context, attrs);
}
public ExpandableGridView(Context context, AttributeSet attrs,
int defStyle)
{
super(context, attrs, defStyle);
}
#Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
if (isExpanded())
{
// Calculate entire height by providing a very large height hint.
// But do not use the highest 2 bits of this integer; those are
// reserved for the MeasureSpec mode.
int expandSpec = MeasureSpec.makeMeasureSpec(
Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec);
ViewGroup.LayoutParams params = getLayoutParams();
params.height = getMeasuredHeight();
}
else
{
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
public void setExpanded(boolean expanded)
{
this.expanded = expanded;
}
}
add this code
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
album_image_grid_view.setNestedScrollingEnabled(true);
}
or you can use RecyclerView instead of GridView
I have a Xamarin Android porject with MvvmCross.
For testing, I added a CustomImageView with a HslBackground property
public class CustomImageView : ImageView
{
private HslColor _hslBackground;
public CustomImageView (Context context)
: base(context) { }
public CustomImageView (Context context, IAttributeSet attrs)
: base(context, attrs) { }
public HslColor HslBackground
{
get { return _hslBackground; }
set
{
if (_hslBackground != value)
{
_hslBackground = value;
byte r, g, b;
value.ToRGB(out r, out g, out b);
this.Background = new ColorDrawable(new Color(r, g, b));
}
}
}
}
Here is my layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Example.MVVM.Droid.Controls.CustomImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/colorView"
android:adjustViewBounds="true"
local:MvxBind="HslBackground HslColor" />
</LinearLayout>
I added breakpoints to the HslBackground property, but either getter nor setter is called. Any idea what to do? I am using the latest MvvmCross from Nuget.
Update 1:
I see in the log
MvxBind:Error: 0.99 View type not found - md56c24830106cce038b53f4325e503c583.CustomImageView
MvxBind:Error: 0.99 View type not found - md56c24830106cce038b53f4325e503c583.CustomImageView
[art] JNI RegisterNativeMethods: attempt to register 0 native methods for md56c24830106cce038b53f4325e503c583.CustomImageView
Update 2
Binding the property to TextView works
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="24dp"
local:MvxBind="Text HslColor" />
I am porting a native Android app to Xamarin + MVVMCross. On my Native Android app I was easily able to create my custom DateDisplayPicker and use it. I'm having trouble in Xamarin. My control lives here:
My DateDisplayPicker.cs looks like so:
namespace XxxxXxxx.Droid.CustomViews
{
public class DateDisplayPicker : TextView, DatePickerDialog.IOnDateSetListener
{
private readonly Context context;
private readonly Calendar calendar;
protected DateDisplayPicker(IntPtr javaReference, JniHandleOwnership transfer) : base(javaReference, transfer)
{
}
public DateDisplayPicker(Context context) : base(context)
{
}
public DateDisplayPicker(Context context, IAttributeSet attrs) : base(context, attrs)
{
this.context = context;
SetAttributes();
this.calendar = Calendar.Instance;
}
public DateDisplayPicker(Context context, IAttributeSet attrs, int defStyle) : base(context, attrs, defStyle)
{
this.context = context;
calendar = Calendar.Instance;
}
private void SetAttributes()
{
Click += (sender, args) => ShowDateDialog();
}
private void ShowDateDialog()
{
var c = Calendar.Instance;
var dp = new DatePickerDialog(context, this, c.Get(CalendarField.Year),
c.Get(CalendarField.Month), c.Get(CalendarField.DayOfMonth));
dp.Show();
}
public void OnDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth)
{
Text = String.Format("%s/%s/%s", monthOfYear + 1, dayOfMonth, year);
calendar.Set(year, monthOfYear, dayOfMonth);
}
public void AddDay()
{
calendar.Add(CalendarField.Date, 1);
Text = String.Format("%s/%s/%s", calendar.Get(CalendarField.Month) + 1,
calendar.Get(CalendarField.DayOfMonth), calendar.Get(CalendarField.Year));
}
public void SubtractDay()
{
calendar.Add(CalendarField.Date, -1);
Text = String.Format("%s/%s/%s", calendar.Get(CalendarField.Month) + 1,
calendar.Get(CalendarField.DayOfMonth), calendar.Get(CalendarField.Year));
}
public string GetDate()
{
var sdf = new SimpleDateFormat("yyyyMMdd");
return sdf.Format(calendar.Time);
}
}
}
And them I'm accessing it in my Android fragment like so:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content"
android:layout_width="fill_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:orientation="vertical">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true">
<com.workspace.xxxxxxxx.droid.customviews.DateDisplayPicker
android:id="#+id/managerDate"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAlignment="center"
android:layout_centerHorizontal="true"
android:text="XX-XX-XXXX"
android:textSize="16sp"
android:textColor="#android:color/holo_blue_dark"
style="#android:style/Widget.Holo.Spinner"
android:hint="Date" />
<ImageButton
android:id="#+id/managerDateMinusButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toLeftOf="#id/managerDate"
android:layout_marginRight="#dimen/button_padding"
android:src="#drawable/minus"
android:background="#android:color/transparent" />
<ImageButton
android:id="#+id/managerDatePlusButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/managerDate"
android:layout_marginLeft="#dimen/button_padding"
android:src="#drawable/plus"
android:background="#android:color/transparent" />
</RelativeLayout>
<ExpandableListView
android:id="#+id/managerExpandableListView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawSelectorOnTop="true"
android:stackFromBottom="false"
android:layout_marginLeft="15dp"
android:layout_marginRight="15dp"
android:layout_marginBottom="15dp" />
</LinearLayout>
<ProgressBar
android:id="#+id/progressBar1"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:visibility="invisible" />
<TextView
android:id="#+id/assignedMessageText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:gravity="center"
android:text="No tasks today."
android:visibility="visible"
android:layout_below="#id/progressBar1" />
</RelativeLayout>
From the few examples I've seen this is pretty much how they've been set up but I must be missing something. Any ideas? I've confirmed my namespace for the control in the axml is all lowercase. When my application errors out I get:
Pending exception is:
android.view.InflateException: Binary XML file line #1: Error inflating class com.workspace.xxxxxxxx.droid.customviews.DateDisplayPicker
(raw stack trace not found)
Caused by:
java.lang.ClassNotFoundException: Didn't find class "com.workspace.xxxxxxxx.droid.customviews.DateDisplayPicker" on path: DexPathList[[zip file "/data/app/com.workspace.xxxxxxxx-1.apk"],nativeLibraryDirectories=[/data/app-lib/com.workspace.xxxxxxxx-1, /vendor/lib, /system/lib]]
Never mind I was just being dumb. If I leave off the "com." this works so it seems like the lesson learned here is to use EXACTLY what the namespace is on the control class, in this case it was "xxxxxxxx.droid.customviews.DateDisplayPicker" in the axml. Hope this helps anyone else who strugged with this!
I'm currently creating an app for Android using MvvmCross. Part of that app requires a MvxListView, where each item has 2 TextViews. One of these TextViews are hidden by default. I'm looking to implement an accordion like functionality, where clicking on the first TextView will show/hide the other TextView.
I've currently gotten most of this to work with the MvvmCross Visibility Plugin, but the click event is bound to the MvxListView instead of the TextView inside it. What I've currently gotten to work looks like this:
FirstViewModel:
public class FirstViewModel
: MvxViewModel
{
public FirstViewModel(IListService listService)
{
Interests = new ObservableCollection<Interest>();
List<Interest> tempInterests = listService.GetInterestFeeds("");
foreach (var interest in tempInterests)
{
interest._parent = this;
Interests.Add(interest);
}
var pluginLoader = new PluginLoader();
pluginLoader.EnsureLoaded();
}
private ObservableCollection<Interest> _interests;
public ObservableCollection<Interest> Interests
{
get { return _interests; }
set { _interests = value; RaisePropertyChanged(() => Interests); }
}
public ICommand ItemVisibleCommand
{
get
{
return new MvxCommand<Interest>(item => item.IsVisible = !item.IsVisible);
}
}
}
FirstView:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
...>
<Mvx.MvxListView
...
local:MvxBind="ItemsSource Interests"
local:MvxItemTemplate="#layout/item_interests" />
</LinearLayout>
item_interests:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="30dp"
local:MvxBind="Text InterestName" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="20dp"
local:MvxBind="Text InterestDescription; Visibility IsVisible, Converter=Visibility" />
</LinearLayout>
In order to bind it to the TextView inside the MvxListView, I've been trying to modify my code to something similar to How to bind ItemClick in MvxListView in MvxListView as per the anwser by Stuart, resulting in the following code:
item_interest:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="30dp"
local:MvxBind="Text InterestName; Click ItemVisibleCommand" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="20dp"
local:MvxBind="Text InterestDescription; Visibility IsVisible, Converter=Visibility" />
</LinearLayout>
FirstViewModel:
public class FirstViewModel
: MvxViewModel
{
public FirstViewModel(IListService listService)
{
Interests = new ObservableCollection<Interest>();
List<Interest> tempInterests = listService.GetInterestFeeds("");
foreach (var interest in tempInterests)
{
interest._parent = this;
Interests.Add(interest);
}
var pluginLoader = new PluginLoader();
pluginLoader.EnsureLoaded();
}
private ObservableCollection<Interest> _interests;
public ObservableCollection<Interest> Interests
{
get { return _interests; }
set { _interests = value; RaisePropertyChanged(() => Interests); }
}
public void MakeItemVisible(bool isVisible)
{
isVisible = !isVisible;
}
Interest:
public class Interest : INotifyPropertyChanged
{
public string InterestId { get; set; }
public string InterestName { get; set; }
public string InterestDescription { get; set; }
public event PropertyChangedEventHandler PropertyChanged;
public FirstViewModel _parent { get; set; }
private bool _isVisible;
public bool IsVisible
{
get { return _isVisible; }
set
{
_isVisible = value;
onPropertyChanged(this, "IsVisible");
}
}
private void onPropertyChanged(object sender, string propertyName)
{
if (this.PropertyChanged != null)
{
PropertyChanged(sender, new PropertyChangedEventArgs(propertyName));
}
}
public Interest(string id, string name, string description)
{
//Initialisers
}
private MvxCommand<bool> _itemVisible;
public ICommand ItemVisibleCommand
{
get
{
_itemVisible = _itemVisible ?? new MvxCommand<bool>(IsVisible => _parent.MakeItemVisible(IsVisible));
return _itemVisible;
}
}
}
resulting in the following exception:
04-04 15:05:40.575 I/MonoDroid(18011): UNHANDLED EXCEPTION: System.NullReferenceException: Object reference not set to an instance of an object
04-04 15:05:40.575 I/MonoDroid(18011): at Cirrious.MvvmCross.ViewModels.MvxCommand`1<bool>.Execute (object) <IL 0x00010, 0x00088>
04-04 15:05:40.575 I/MonoDroid(18011): at Cirrious.MvvmCross.Binding.Droid.Target.MvxViewClickBinding.ViewOnClick (object,System.EventArgs) <IL 0x0001f, 0x000fb>
04-04 15:05:40.575 I/MonoDroid(18011): at Android.Views.View/IOnClickListenerImplementor.OnClick (Android.Views.View) [0x0000d] in /Users/builder/data/lanes/monodroid-mlion-monodroid-4.12-series/a1e3982a/source/monodroid/src/Mono.Android/platforms/android-15/src/generated/Android.Views.View.cs:1615
04-04 15:05:40.575 I/MonoDroid(18011): at Android.Views.View/IOnClickListenerInvoker.n_OnClick_Landroid_view_View_ (intptr,intptr,intptr) [0x00011] in /Users/builder/data/lanes/monodroid-mlion-monodroid-4.12-series/a1e3982a/source/monodroid/src/Mono.Android/platforms/android-15/src/generated/Android.Views.View.cs:1582
04-04 15:05:40.575 I/MonoDroid(18011): at (wrapper dynamic-method) object.a963c1ac-b573-4022-b41d-f0f002438c84 (intptr,intptr,intptr) <IL 0x00017, 0x00043>
Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object
Thanks in advance to anyone who's taken the time to read all that :)
UPDATE - I tried to do as Stuart suggested, and got the following solution:
First off, to preserve the original Interest entity, it got wrapped in an InterestWrapper.
public class InterestWrapper : INotifyPropertyChanged
{
private Interest _interest;
private InterestAndroidViewModel _parent; //TO-DO
public Interest Item { get { return _interest; } }
public event PropertyChangedEventHandler PropertyChanged;
private bool _isVisible;
public bool IsVisible
{
get { return _isVisible; }
set
{
_isVisible = value;
onPropertyChanged(this, "IsVisible");
}
}
private void onPropertyChanged(object sender, string propertyName)
{
if (this.PropertyChanged != null)
{
PropertyChanged(sender, new PropertyChangedEventArgs(propertyName));
}
}
public InterestWrapper(Interest interest, InterestAndroidViewModel parent)
{
IsVisible = false;
_interest = interest;
_parent = parent;
}
public IMvxCommand ItemVisibleCommand
{
get
{
return new MvxCommand(() => _parent.MakeItemVisible(_interest));
}
}
}
FirstViewModel
public class FirstViewModel
: MvxViewModel
{
public FirstViewModel(IListService listService)
{
Interests = new ObservableCollection<InterestWrapper>();
List<Interest> tempInterests = listService.GetInterestFeeds("");
foreach (var interest in tempInterests)
{
InterestWrapper wrapper = new InterestWrapper(interest, this);
Interests.Add(wrapper);
}
}
private ObservableCollection<InterestWrapper> _interests;
public ObservableCollection<InterestWrapper> Interests
{
get { return _interests; }
set { _interests = value; RaisePropertyChanged(() => Interests); }
}
public void MakeItemVisible(Interest interest)
{
if (interest.IsVisible)
{
interest.IsVisible = !interest.IsVisible;
}
else
{
foreach (var _interest in _interests)
{
_interest.Item.IsVisible = false;
}
interest.IsVisible = !interest.IsVisible;
}
}
}
item_interest:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
...
<RelativeLayout
...
<TextView
...
local:MvxBind="Text Item.InterestName; Click ItemVisibleCommand" />
<Mvx.MvxImageView
...
local:MvxBind="Visibility Item.IsVisible, Converter=InvertedVisibility; Click ShowEducationsCommand" />
</RelativeLayout>
</RelativeLayout>
The local:MvxBind="Text InterestName; Click ItemVisibleCommand" can only really call a non-parameterized MvxCommand - it can't call MvxCommand<bool> as it doesn't know what the bool value is.
If you wanted to, you could use the CommandParameter converter to pass in the value - e.g. local:MvxBind="Text InterestName; Click CommandParameter(ItemVisibleCommand, IsVisible)"
But overall, in this case I'd probably recommend rewriting ItemVisibleCommand as just a "toggle visible" command instead
Look through this question it's the as your one and has the solution suggested by Stuart, so think it's what you are looking for.
Binding button click in ListView template MvvMCross