xamarin forms Tabbed page title no wrap - xamarin.forms

i have tabbed page with number of pages , the issue here that the title of the page is not appearing well, it need to be no wrap or expand to fit the text.
any suggestion to solve this issue.

You Need to create one TabbedPageRenderer
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Android.App;
using Android.Content;
using Android.OS;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android.AppCompat;
using AppTab.Droid;
using Android.Support.V4.View;
using Android.Support.Design.Widget;
using System.ComponentModel;
using Xamarin.Forms.Platform.Android;
using AppTab;
using Android.Graphics.Drawables;
using Android.Graphics;
[assembly: ExportRenderer(typeof(CustomTabbedPage), typeof(ScrollableTabbedPage))]
namespace AppTab.Droid
{
public class ScrollableTabbedPage : TabbedPageRenderer
{
public override void OnViewAdded(Android.Views.View child)
{
base.OnViewAdded(child);
var tabLayout = child as TabLayout;
if (tabLayout != null)
{
tabLayout.TabMode = TabLayout.ModeScrollable;
}
}
public static void Init()
{
var unused = DateTime.UtcNow;
}
private CustomTabbedPage FormsTabbedPage => Element as CustomTabbedPage;
private Android.Graphics.Color _selectedColor = Android.Graphics.Color.Black;
private static readonly Android.Graphics.Color DefaultUnselectedColor = Xamarin.Forms.Color.Gray.ToAndroid();
private static Android.Graphics.Color _barBackgroundDefault;
private Android.Graphics.Color _unselectedColor = DefaultUnselectedColor;
ViewPager _viewPager;
TabLayout _tabLayout;
protected override void OnElementChanged(ElementChangedEventArgs<TabbedPage> e)
{
base.OnElementChanged(e);
// Get tabs
for (var i = 0; i < ChildCount; i++)
{
var v = GetChildAt(i);
var pager = v as ViewPager;
if (pager != null)
_viewPager = pager;
else if (v is TabLayout)
_tabLayout = (TabLayout)v;
}
if (e.OldElement != null)
{
_tabLayout.TabSelected -= TabLayout_TabSelected;
_tabLayout.TabUnselected -= TabLayout_TabUnselected;
}
if (e.NewElement != null)
{
_barBackgroundDefault = (_tabLayout.Background as ColorDrawable)?.Color ??
Android.Graphics.Color.Blue;
SetSelectedColor();
SetBarBackgroundColor();
_tabLayout.TabSelected += TabLayout_TabSelected;
_tabLayout.TabUnselected += TabLayout_TabUnselected;
SetupTabColors();
SelectTab(0);
}
}
void SelectTab(int position)
{
if (_tabLayout.TabCount > position)
{
_tabLayout.GetTabAt(position).Icon?
.SetColorFilter(_selectedColor, PorterDuff.Mode.SrcIn);
_tabLayout.GetTabAt(position).Select();
}
else
{
throw new IndexOutOfRangeException();
}
}
void SetupTabColors()
{
_tabLayout.SetSelectedTabIndicatorColor(_selectedColor);
_tabLayout.SetTabTextColors(_unselectedColor, _selectedColor);
for (int i = 0; i < _tabLayout.TabCount; i++)
{
var tab = _tabLayout.GetTabAt(i);
tab.Icon?.SetColorFilter(_unselectedColor, PorterDuff.Mode.SrcIn);
}
}
private void TabLayout_TabUnselected(object sender, TabLayout.TabUnselectedEventArgs e)
{
var tab = e.Tab;
tab.Icon?.SetColorFilter(_unselectedColor, PorterDuff.Mode.SrcIn);
}
private void TabLayout_TabSelected(object sender, TabLayout.TabSelectedEventArgs e)
{
var tab = e.Tab;
_viewPager.CurrentItem = tab.Position;
tab.Icon?.SetColorFilter(_selectedColor, PorterDuff.Mode.SrcIn);
}
protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
int lastPosition = _tabLayout.SelectedTabPosition;
switch (e.PropertyName)
{
case nameof(CustomTabbedPage.BarBackgroundColor):
case nameof(CustomTabbedPage.BarBackgroundApplyTo):
SetBarBackgroundColor();
SetupTabColors();
SelectTab(lastPosition);
break;
case nameof(CustomTabbedPage.SelectedColor):
SetSelectedColor();
SetupTabColors();
SelectTab(lastPosition);
break;
default:
base.OnElementPropertyChanged(sender, e);
break;
}
}
private void SetSelectedColor()
{
if (FormsTabbedPage.SelectedColor != default(Xamarin.Forms.Color))
_selectedColor = FormsTabbedPage.SelectedColor.ToAndroid();
}
private void SetBarBackgroundColor()
{
if (FormsTabbedPage.BarBackgroundApplyTo.HasFlag(BarBackgroundApplyTo.Android))
{
_tabLayout.SetBackgroundColor(FormsTabbedPage.BarBackgroundColor.ToAndroid());
_unselectedColor = FormsTabbedPage.BarBackgroundColor != default(Xamarin.Forms.Color)
? FormsTabbedPage.BarBackgroundColor.ToAndroid()
: DefaultUnselectedColor;
}
else
{
_tabLayout.SetBackgroundColor(_barBackgroundDefault);
_unselectedColor = DefaultUnselectedColor;
}
}
}
}
Second you Need CustomTabbedPage class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
namespace AppTab
{
[Flags]
public enum BarBackgroundApplyTo
{
None = 0x01,
Android = 0x10,
iOS = 0x100
}
public class CustomTabbedPage : TabbedPage
{
public CustomTabbedPage()
{
}
public static readonly BindableProperty SelectedColorProperty =
BindableProperty.Create(nameof(SelectedColor), typeof(Color), typeof(CustomTabbedPage), default(Color));
public Color SelectedColor
{
get => (Color)GetValue(SelectedColorProperty);
set => SetValue(SelectedColorProperty, value);
}
public static readonly BindableProperty BarBackgroundApplyToProperty =
BindableProperty.Create(nameof(BarBackgroundApplyTo), typeof(BarBackgroundApplyTo), typeof(CustomTabbedPage), BarBackgroundApplyTo.Android);
public BarBackgroundApplyTo BarBackgroundApplyTo
{
get => (BarBackgroundApplyTo)GetValue(BarBackgroundApplyToProperty);
set => SetValue(BarBackgroundApplyToProperty, value);
}
public new static readonly BindableProperty BarBackgroundColorProperty =
BindableProperty.Create(nameof(BarBackgroundColor), typeof(Color), typeof(CustomTabbedPage), default(Color));
public new Color BarBackgroundColor
{
get => (Color)GetValue(BarBackgroundColorProperty);
set => SetValue(BarBackgroundColorProperty, value);
}
}
}
And Third You Need CustomMain Page
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Xamarin.Forms;
namespace AppTab
{
public class CustomMain : CustomTabbedPage
{
public CustomMain()
{
BarBackgroundApplyTo = BarBackgroundApplyTo.Android;
//BarBackgroundColor = Color.Red;
Children.Add(new abc() { Title = "ABC"});
Children.Add(new xyz() { Title = "XYZ" });
Children.Add(new pqr() { Title = "PQR" });
Children.Add(new str() { Title = "STR" });
Children.Add(new ftx() { Title = "FTX" });
Children.Add(new dtb() { Title = "DTB" });
}
}
}
Click here for ScreenShot

In Resources->Layout->Tabbar.xml set tabMode to "scrollable".
It should work.

Related

Allow popups to work in Xamarin Forms WebView

This seems like a simple thing - I want to use a WebView to load / run some JavaScript from a 3rd party.
When I load the page I get a message saying "You must allow popups for this to work". I think I need to create a custom WebView (for iOS and Android!?) and I assume I need one in the shared project too?
I added this to my Android project:
using Android.Content;
using MyApp.Custom;
using MyApp.Droid.Custom;
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;
[assembly: ExportRenderer(typeof(CustomWebView), typeof(CustomWebViewRenderer))]
namespace MyApp.Droid.Custom
{
public class CustomWebViewRenderer : WebViewRenderer
{
public CustomWebViewRenderer(Context context) : base(context)
{
}
protected override void OnElementChanged(ElementChangedEventArgs<WebView> e)
{
base.OnElementChanged(e);
Control.Settings.JavaScriptCanOpenWindowsAutomatically = true;
Control.Settings.JavaScriptEnabled = true;
}
}
}
and this to my shared project
using Xamarin.Forms;
namespace MyKRing.Custom
{
public class CustomWebView : WebView
{
}
}
and then used "CustomWebView" in my XAML.
<custom:CustomWebView x:Name="WebView"
HeightRequest="1000"
Source="{Binding WebViewContent}"
WidthRequest="1000" />
My TestPageViewModel has
public WebViewSource WebViewContent
{
get => _webViewContent;
set => SetProperty(ref _webViewContent, value);
}
public TestPageViewModel()
{
AmountEntryFrameVisible = true;
NuapayFrameVisible = false;
ConfirmLoadCommand = new Command(ExecuteConfirmLoadCommand);
var localHtml = new HtmlWebViewSource();
localHtml.Html = #"<html>
<body>
<p>This is a test</p>
<script src='https://testurl.com/test.js\'></script>
<script>
TestJS.showUI('1234567890', 'https://testurl.com/ui/');
</script>
</body>
</html>";
WebViewContent = localHtml;
}
With the aim of making the JS run when the page is loaded by WebView.
Am I anywhere close? What is wrong with the above, as it just doesn't do anything (that ( can see).
1. Create the CustomWebView and create the ShowDialog method.
public class CustomWebView : WebView
{
Action<string> action;
public static readonly BindableProperty UriProperty = BindableProperty.Create(
propertyName: "Uri",
returnType: typeof(string),
declaringType: typeof(CustomWebView ),
defaultValue: default(string));
public string Uri
{
get { return (string)GetValue(UriProperty); }
set { SetValue(UriProperty, value); }
}
public void RegisterAction(Action<string> callback)
{
action = callback;
}
public void Cleanup()
{
action = null;
}
public void ShowDialog(string data)
{
if (action == null || data == null)
{
return;
}
action.Invoke(data);
}
}
2. Consume the CustomWebView
<local:CustomWebView x:Name="customWebView " Uri="index.html" />
3. Register the ShowDiaplg action to be invoked from JavaScript
customWebView.RegisterAction(data => DisplayAlert("Alert", DateTime.Now + "/n" + data, "OK"));
4. Create the custom renderer on Android platform.
CustomWebViewRenderer .cs:
[assembly: ExportRenderer(typeof(CustomWebView ), typeof(CustomWebViewRenderer))]
namespace CustomRenderer.Droid
{
public class CustomWebViewRenderer: WebViewRenderer
{
const string JavascriptFunction = "function invokeCSharpAction(data){jsBridge2.showDialog(data);}";
Context _context;
public CustomWebViewRenderer (Context context) : base(context)
{
_context = context;
}
protected override void OnElementChanged(ElementChangedEventArgs<WebView> e)
{
base.OnElementChanged(e);
if (e.OldElement != null)
{
Control.RemoveJavascriptInterface("jsBridge");
((CustomWebView )Element).Cleanup();
}
if (e.NewElement != null)
{
Control.SetWebViewClient(new JavascriptWebViewClient2(this, $"javascript: {JavascriptFunction}"));
Control.AddJavascriptInterface(new JSBridge2(this), "jsBridge2");
Control.LoadUrl($"file:///android_asset/Content/{((CustomWebView )Element).Uri}");
}
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
((CustomWebView )Element).Cleanup();
}
base.Dispose(disposing);
}
}
}
JavascriptWebViewClient2.cs:
public class JavascriptWebViewClient2 : FormsWebViewClient
{
string _javascript;
public JavascriptWebViewClient2(CustomWebViewRenderer renderer, string javascript) : base(renderer)
{
_javascript = javascript;
}
public override void OnPageFinished(WebView view, string url)
{
base.OnPageFinished(view, url);
view.EvaluateJavascript(_javascript, null);
}
}
JSBridge2.cs:
public class JSBridge2 : Java.Lang.Object
{
readonly WeakReference<CustomWebViewRenderer > hybridWebViewRenderer;
public JSBridge2(CustomWebViewRenderer hybridRenderer)
{
hybridWebViewRenderer = new WeakReference<CustomWebViewRenderer >(hybridRenderer);
}
[JavascriptInterface]
[Export("showDialog")]
public void ShowDialog(string data)
{
CustomWebViewRenderer hybridRenderer;
if (hybridWebViewRenderer != null && hybridWebViewRenderer.TryGetTarget(out hybridRenderer))
{
((CustomWebView)hybridRenderer.Element).ShowDialog(data);
}
//string ret = "Alert :" + DateTime.Now;
//return ret;
}
}
I followed the code sample in the link below. https://learn.microsoft.com/en-us/samples/xamarin/xamarin-forms-samples/customrenderers-hybridwebview/

Using SQLite-net-pcl and can't update the data

So i have this really annoying problem where i Can't seem to get it to update any of the databases i have created, whats worse the i can see the instance is showing the updated information but isn't applying it. I'm really new to this and is my first course project.
This is the code that is being used to update the data:
'''
using Project.Database;
using Project.DataClasses;
using Project.Pages.SuperPages;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Essentials;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
namespace Project.Pages.UpdateDeleteListItem
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class UpdateDeleteList : ContentPage
{
private new readonly Label Title;
private Style LabelStyle;
private StoreDetails UpdateStoreDetails;
private Entry SNum;
private Entry SName;
private Entry SMName;
private Entry Addy;
public UpdateDeleteList(string pageType, object Item)
{
InitializeComponent();
BindingContext = Item;
UpdateStoreDetails = (StoreDetails)Item;
SetLabelStyle();
string titleMsg = "Update or Delete Selected " + pageType;
Frame frame = new Frame();
Label title = new Label() {Text = titleMsg };
Title = title;
StackLayout titleStack = new StackLayout() { Children = { Title } };
frame.Content = titleStack;
if (pageType == "Store")
{
StoreUDLItem(frame);
}
if (pageType == "Ticket")
{
TicketUDLItem(frame);
}
StylePage();
}
private void SaveButton_Clicked(object sender, EventArgs args)
{
if (StoreCheckValues() == true)
{
var store = SName;
var storeManager = SMName;
var storeNumber = SNum;
var address = Addy;
var storeDataAccess = new StoreDataAccess();
UpdateStoreDetails.StoreName = store.Text;
UpdateStoreDetails.StoreManger = storeManager.Text;
UpdateStoreDetails.StoreNumber = storeNumber.Text;
UpdateStoreDetails.Address = address.Text;
//MerchandiserKey = GetMerchId()
storeDataAccess.SaveStoreDetails(UpdateStoreDetails);
storeDataAccess.SaveAllStoreDetails();
}
'''
here is the data access methods:
'''
using Project.DataClasses;
using SQLite;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.IO;
using System.Text;
using Xamarin.Forms;
namespace Project.Database
{
class StoreDataAccess
{
private SQLiteConnection database;
private static object collisionLock = new object();
public ObservableCollection<StoreDetails> StoreDetails { get; set; }
public StoreDataAccess()
{
database = DependencyService.Get<IDatabaseConnection>().DbConnectionStore();
database.CreateTable<StoreDetails>();
this.StoreDetails = new ObservableCollection<StoreDetails>(database.Table<StoreDetails>());
//AddNewTicket(new Ticket ticket);
}
//add ticket method
public void AddNewStore(StoreDetails item)
{
this.StoreDetails.Add(item);
}
//retrieve ticket method
public StoreDetails GetStoreDetails(int id)
{
lock (collisionLock)
{
return database.Table<StoreDetails>().FirstOrDefault(StoreDetails => StoreDetails.StoreId == id);
}
}
//save ticket
public int SaveStoreDetails(StoreDetails storeDetailsInstance)
{
lock (collisionLock)
{
if (storeDetailsInstance.StoreId != 0)
{
database.Update(storeDetailsInstance);
return storeDetailsInstance.StoreId;
}
else
{
database.Insert(storeDetailsInstance);
return storeDetailsInstance.StoreId;
}
//database.Commit();
}
}
public void SaveAllStoreDetails()
{
lock (collisionLock)
{
foreach (var storeDetailsInstance in this.StoreDetails)
{
if (storeDetailsInstance.StoreId != 0)
{
database.Update(storeDetailsInstance);
}
else
{
database.Insert(storeDetailsInstance);
}
}
}
}
'''
This is the page that is sending the information to the first code block to bind the data too
'''
using Project.Database;
using Project.DataClasses;
using Project.Pages.UpdateDeleteListItem;
using SQLite;
using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
namespace Project.Pages.ListPages
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class StoreList : ContentPage
{
private ObservableCollection<StoreDetails> Items { get; set; }
private readonly StoreDataAccess storeDataAccess;
private readonly SQLiteConnection database;
public StoreList()
{
InitializeComponent();
storeDataAccess = new StoreDataAccess();
this.BindingContext = this.storeDataAccess;
Items = storeDataAccess.StoreDetails;
StoreView.ItemsSource = Items;
}
async void Handle_ItemTapped(object sender, ItemTappedEventArgs e)
{
if (e.Item == null) { return; }
else
{
//var id = Items[e.ItemIndex].StoreId;
await Navigation.PushAsync(new UpdateDeleteList("Store", e.Item));
//Deselect Item
((ListView)sender).SelectedItem = null;
}
}
//page reload handle
protected override void OnAppearing()
{
base.OnAppearing();
var dbName = "StoreListDatabase.db3";
var path = Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.Personal), dbName);
if (database == null)
{
new StoreDataAccess();
}
using (SQLiteConnection conn = new SQLiteConnection(path))
{
Items = storeDataAccess.StoreDetails;
StoreView.ItemsSource = Items;
}
}
}
}
'''
and lastly here is my databbase model for it:
'''
using System;
using System.Collections.Generic;
using System.Text;
using Xamarin.Forms;
using SQLite;
using System.ComponentModel;
namespace Project.DataClasses
{
class StoreDetails : INotifyPropertyChanged
{
private int _storeId;
[PrimaryKey, AutoIncrement, NotNull]
public int StoreId
{
get { return _storeId; }
set { _storeId = value; OnPropertyChanged(nameof(StoreId)); }
}
private string _storeName;
[NotNull, DefaultValue("Enter Store Name")]
public string StoreName
{
get { return _storeName; }
set { _storeName = value; OnPropertyChanged(nameof(_storeName)); }
}
private string _storeManger;
[NotNull, DefaultValue("Enter Store Managers Name")]
public string StoreManger
{
get { return _storeManger; }
set { _storeManger = value; OnPropertyChanged(nameof(StoreManger)); }
}
private string _storeNumber;
[NotNull, DefaultValue("Enter Store Number")]
public string StoreNumber
{
get { return _storeNumber; }
set { _storeNumber = value; OnPropertyChanged(nameof(StoreNumber)); }
}
private string _address;
[NotNull, DefaultValue("Enter Address")]
public string Address
{
get { return _address; }
set { _address = value; OnPropertyChanged(nameof(Address)); }
}
private int _merchandiserKey;
[NotNull]
public int MerchandiserKey
{
get { return _merchandiserKey; }
set { _merchandiserKey = value; OnPropertyChanged(nameof(MerchandiserKey)); }
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyName)
{
this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
'''
any help would be greatly appreciated
'''
public int SaveStoreDetails(StoreDetails storeDetailsInstance)
{
lock (collisionLock)
{
if (storeDetailsInstance.StoreId != 0)
{
database.Update(storeDetailsInstance);
return storeDetailsInstance.StoreId;
}
else
{
database.Insert(storeDetailsInstance);
return storeDetailsInstance.StoreId;
}
//database.Commit();
}
}
'''
this is the area where it all seems to be going wrong i just don't know why
Thank You Jason, you were correct in that the error was in calling both the savefunctions and overwriting it!!

Could not implement NavigationPageRenderer Custom renderer xamarin form

I have google a lot about building CustomRenderer to display custom navigationpage on xamarin form (to display gradient on navigationbar) but did not succeed.
here is my code:
using System;
using System.Collections.Generic;
using System.Text;
using Xamarin.Forms;
namespace BillerApp
{
public class GradientNavigationBar: NavigationPage
{
public GradientNavigationBar(Page page): base(page)
{
}
public GradientNavigationBar() : base()
{
}
public static readonly BindableProperty StartColorProperty = BindableProperty.Create(
nameof(StartColor),
typeof(Color),
typeof(GradientNavigationBar),
Color.Default);
public static readonly BindableProperty EndColorProperty = BindableProperty.Create(
nameof(EndColor),
typeof(Color),
typeof(GradientNavigationBar),
Color.Default);
public Color StartColor {
get { return (Color)GetValue(StartColorProperty); }
set { SetValue(StartColorProperty, value); }
}
public Color EndColor
{
get { return (Color)GetValue(EndColorProperty); }
set { SetValue(EndColorProperty, value); }
}
}
}
and following is the renderer on Xamarin.Droid
using Android.App;
using Android.Content;
using Android.OS;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Xamarin.Forms;
using BillerApp;
using Xamarin.Forms.Platform.Android;
using Android.Graphics.Drawables;
using BillerApp.Droid;
using System.ComponentModel;
[assembly: ExportRenderer(typeof(GradientNavigationBar), typeof(GrandientNavigationBarRenderer))]
namespace BillerApp.Droid
{
[Activity(Name = "com.companyname.BillerApp.MainActivity")]
public class GrandientNavigationBarRenderer: Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer
{
//public GrandientNavigationBarRenderer(Context context): base(context){} //can not use this constructor
protected override void OnElementChanged(ElementChangedEventArgs<NavigationPage> e)
{
base.OnElementChanged(e); // I got Invalid Cast Exception if Inherit from NavigationRenderer
if (e.OldElement != null || Element == null)
{
return;
}
var p = this.Element as GradientNavigationBar;
var context = (Activity)this.Context;
var sc = new int[] { p.StartColor.ToAndroid(), p.EndColor.ToAndroid() };
var grad = new GradientDrawable(GradientDrawable.Orientation.TopBottom, sc);
var t = context.ActionBar; // here i got null
t.SetSplitBackgroundDrawable(grad);
context.ActionBar.SetBackgroundDrawable(grad);
}
}
}
this is what i am trying to achieve:
I am using VS 2015 Community edition and have updated SDK tools to date
I would do it simply by adding something like this to your layout folder:
toolbar_gradient.xml
<gradient
android:type="linear"
android:startColor="#F3A183"
android:endColor="#EC6F66"
android:angle="270"/>
</shape>
Then in your Toolbar.xml add this line of code:
android:background="#layout/toolbar_gradient"

How to render a xamarin.forms view in a custom renderer

I've got the following code:
Shared project:
using System;
using Xamarin.Forms;
namespace XamarinForms.Framework.Controls
{
public enum DrawerPosition
{
Left,
Right
}
public interface ISideDrawerNativeEventProxy
{
void RaiseSlideChanged(float percentage);
}
public class SideDrawer : Grid, ISideDrawerNativeEventProxy
{
#region DrawerSize
public static BindableProperty DrawerSizeProperty = BindableProperty.Create<SideDrawer, MaxedPercentSize>(d => d.DrawerSize, new MaxedPercentSize(MaxedPercentSizeType.Width, 80, 400));
public MaxedPercentSize DrawerSize
{
get { return (MaxedPercentSize) GetValue(DrawerSizeProperty); }
set { SetValue(DrawerSizeProperty, value); }
}
#endregion DrawerSize
#region IsOpen
public static BindableProperty IsOpenProperty = BindableProperty.Create<SideDrawer, bool>(d => d.IsOpen, default(bool));
public bool IsOpen
{
get { return (bool) GetValue(IsOpenProperty); }
set { SetValue(IsOpenProperty, value); }
}
#endregion IsOpen
#region DrawerPosition
public static BindableProperty DrawerPositionProperty = BindableProperty.Create<SideDrawer, DrawerPosition>(d => d.DrawerPosition, default(DrawerPosition));
public DrawerPosition DrawerPosition
{
get { return (DrawerPosition) GetValue(DrawerPositionProperty); }
set { SetValue(DrawerPositionProperty, value); }
}
#endregion DrawerPosition
public static BindableProperty MainContentProperty = BindableProperty.Create<SideDrawer, View>(d => d.MainContent, default(View));
public View MainContent
{
get { return (View) GetValue(MainContentProperty); }
set { SetValue(MainContentProperty, value); }
}
public static BindableProperty DrawerContentProperty = BindableProperty.Create<SideDrawer, View>(d => d.DrawerContent, default(View));
public View DrawerContent
{
get { return (View) GetValue(DrawerContentProperty); }
set { SetValue(DrawerContentProperty, value); }
}
#region DrawerLength
public static BindableProperty DrawerLengthProperty = BindableProperty.Create<SideDrawer, int>(d => d.DrawerLength, default(int), defaultValueCreator: DrawerLengthDefault);
private static int DrawerLengthDefault(SideDrawer bindable)
{
return 300;
}
public int DrawerLength
{
get { return (int) GetValue(DrawerLengthProperty); }
set { SetValue(DrawerLengthProperty, value); }
}
#endregion DrawerLength
#region IsContentTranslated
public static BindableProperty IsContentTranslatedProperty = BindableProperty.Create<SideDrawer, bool>(d => d.IsContentTranslated, true);
public bool IsContentTranslated
{
get { return (bool) GetValue(IsContentTranslatedProperty); }
set { SetValue(IsContentTranslatedProperty, value); }
}
#endregion IsContentTranslated
void ISideDrawerNativeEventProxy.RaiseSlideChanged(float percentage)
{
}
}
}
Android:
using System;
using System.ComponentModel;
using Android.Support.V4.Widget;
using Android.Views;
using Android.Widget;
using Mobile.XamarinForms.Droid.Controls.SideDrawer;
using Mobile.XamarinForms.Framework.Controls;
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;
using Android.Graphics;
using Application = Android.App.Application;
using Color = Android.Graphics.Color;
using RelativeLayout = Android.Widget.RelativeLayout;
using View = Android.Views.View;
[assembly: ExportRenderer(typeof(SideDrawer), typeof(SideDrawerRenderer))]
namespace Mobile.XamarinForms.Droid.Controls.SideDrawer
{
// public class SideDrawerRenderer : Xamarin.Forms.Platform.Android.AppCompat.ViewRenderer<Framework.Controls.SideDrawer, DrawerLayout>, DrawerLayout.IDrawerListener
public class SideDrawerRenderer : ViewRenderer<Framework.Controls.SideDrawer, DrawerLayout>, DrawerLayout.IDrawerListener
{
private DrawerLayout _nativeDrawerLayout;
private MarginLayoutParams _contentLayoutParameters;
private RelativeLayout _contentView;
private TextView _drawerView;
protected override void OnElementChanged(ElementChangedEventArgs<Framework.Controls.SideDrawer> e)
{
base.OnElementChanged(e);
if (this.Control == null)
{
InitializeNativeControl();
}
if (e.OldElement != null)
{
_nativeDrawerLayout.SetDrawerListener(null);
}
if (e.NewElement != null)
{
_nativeDrawerLayout.SetDrawerListener(this);
}
}
private void InitializeNativeControl()
{
_nativeDrawerLayout = new DrawerLayout(Context.ApplicationContext);
_nativeDrawerLayout.SetBackgroundColor(Element.BackgroundColor.ToAndroid());
_contentLayoutParameters = new MarginLayoutParams(LayoutParams.MatchParent, LayoutParams.MatchParent);
var layoutParamsDrawer = new DrawerLayout.LayoutParams(Element.DrawerLength, LinearLayout.LayoutParams.MatchParent);
layoutParamsDrawer.Gravity = GetDrawerGravity();
_drawerView = GetDrawerView(layoutParamsDrawer);
_contentView = GetContentView(_contentLayoutParameters);
// this one works, but i need the content from my forms property
var contentChild = new RelativeLayout(Context.ApplicationContext);
var contentChildLParams = new RelativeLayout.LayoutParams(300, 300);
contentChild.SetBackgroundColor(Color.Yellow);
_contentView.AddView(contentChild, contentChildLParams);
// i need to figure out how to make this work
// var contentRenderer = RendererFactory.GetRenderer(Element.MainContent);
// _contentView.AddView(contentRenderer.ViewGroup, new LayoutParams(LayoutParams.MatchParent, LayoutParams.MatchParent));
_nativeDrawerLayout.AddView(_drawerView);
_nativeDrawerLayout.AddView(_contentView);
SetNativeControl(_nativeDrawerLayout);
}
private int GetDrawerGravity()
{
switch (Element.DrawerPosition)
{
case DrawerPosition.Left:
return (int)GravityFlags.Start;
case DrawerPosition.Right:
return (int)GravityFlags.End;
default:
throw new ArgumentOutOfRangeException();
}
}
private RelativeLayout GetContentView(LayoutParams layoutParameters)
{
var view = new RelativeLayout(Context.ApplicationContext);
view.LayoutParameters = layoutParameters;
view.SetBackgroundColor(Color.Red);
return view;
}
private TextView GetDrawerView(LayoutParams layoutParameters)
{
var view = new TextView(Context.ApplicationContext);
view.LayoutParameters = layoutParameters;
view.SetBackgroundColor(Color.Purple);
view.SetTextColor(Color.Blue);
view.SetText("just some text", TextView.BufferType.Editable);
return view;
}
protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
base.OnElementPropertyChanged(sender, e);
switch (e.PropertyName)
{
case nameof(Framework.Controls.SideDrawer.Height):
break;
case nameof(Framework.Controls.SideDrawer.Width):
break;
}
}
public void OnDrawerClosed(View drawerView)
{
Element.IsOpen = false;
System.Diagnostics.Debug.WriteLine("OnDrawerClosed");
}
public void OnDrawerOpened(View drawerView)
{
Element.IsOpen = true;
System.Diagnostics.Debug.WriteLine("OnDrawerOpened");
}
public void OnDrawerSlide(View drawerView, float slideOffset)
{
switch (Element.DrawerPosition)
{
case DrawerPosition.Left:
_contentView.TranslationX = (int) Math.Abs(Element.DrawerLength*slideOffset);
break;
case DrawerPosition.Right:
_contentView.TranslationX = (int) Math.Abs(Element.DrawerLength*slideOffset)*-1;
break;
default:
throw new ArgumentOutOfRangeException();
}
_nativeDrawerLayout.BringChildToFront(_drawerView);
_nativeDrawerLayout.RequestLayout();
((ISideDrawerNativeEventProxy) Element)?.RaiseSlideChanged(slideOffset);
}
public void OnDrawerStateChanged(int newState)
{
// not really needed
// System.Diagnostics.Debug.WriteLine($"OnDrawerStateChanged {newState}");
}
}
}
How do i output the contents of e.g. MainContent (Shared project property)?
I was unable to find anything in xamarin docs about this and support is rather quiet about this topic so far (guess they are too busy).
Does anyone have experience with this issue?
Update: Reproduction solution
Android container:
internal sealed class FormsElementWrapper : FormsViewGroup
{
public override bool OnInterceptTouchEvent(MotionEvent ev)
{
return false;
}
private readonly IVisualElementRenderer _view;
public FormsElementWrapper(Xamarin.Forms.View content) : base(Application.Context)
{
_view = content != null ? Platform.CreateRenderer(content) : null;
if (_view == null)
return;
AddView(_view.ViewGroup);
}
protected override void OnLayout(bool changed, int left, int top, int right, int bottom)
{
if (_view == null)
return;
_view.Element.Layout(new Rectangle(0.0, 0.0, ContextExtensions.FromPixels(Context, right - left), ContextExtensions.FromPixels(Context, bottom - top)));
_view.UpdateLayout();
}
protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
MeasureSpecMode widthMode = MeasureSpec.GetMode(widthMeasureSpec);
MeasureSpecMode heightMode = MeasureSpec.GetMode(heightMeasureSpec);
int widthSize = MeasureSpec.GetSize(widthMeasureSpec);
int heightSize = MeasureSpec.GetSize(heightMeasureSpec);
int pxHeight = (int) ContextExtensions.ToPixels(Context, _view.Element.HeightRequest);
int pxWidth = (int) ContextExtensions.ToPixels(Context, _view.Element.WidthRequest);
var measuredWidth = widthMode != MeasureSpecMode.Exactly ? (widthMode != MeasureSpecMode.AtMost ? pxHeight : Math.Min(pxHeight, widthSize)) : widthSize;
var measuredHeight = heightMode != MeasureSpecMode.Exactly ? (heightMode != MeasureSpecMode.AtMost ? pxWidth : Math.Min(pxWidth, heightSize)) : heightSize;
SetMeasuredDimension(measuredWidth, measuredHeight);
}
}
android drawer:
using System;
using System.ComponentModel;
using Android.Support.V4.Widget;
using Android.Views;
using Android.Widget;
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;
using Color = Android.Graphics.Color;
using RelativeLayout = Android.Widget.RelativeLayout;
using View = Android.Views.View;
[assembly: ExportRenderer(typeof(SideDrawer), typeof(SideDrawerRenderer))]
namespace MyNamespace.SideDrawer
{
public class SideDrawerRenderer : ViewRenderer<SideDrawer, DrawerLayout>, DrawerLayout.IDrawerListener
{
private DrawerLayout _nativeDrawerLayout;
private FormsElementWrapper _contentView;
private FormsElementWrapper _drawerView;
protected override void OnElementChanged(ElementChangedEventArgs<Framework.Controls.SideDrawer> e)
{
base.OnElementChanged(e);
if (this.Control == null)
{
InitializeNativeControl();
}
if (e.OldElement != null)
{
_nativeDrawerLayout.SetDrawerListener(null);
}
if (e.NewElement != null)
{
_nativeDrawerLayout.SetDrawerListener(this);
}
}
private void InitializeNativeControl()
{
_nativeDrawerLayout = new DrawerLayout(Context.ApplicationContext);
_nativeDrawerLayout.SetBackgroundColor(Element.BackgroundColor.ToAndroid());
AddDrawerLayer(_nativeDrawerLayout);
AddContentLayer(_nativeDrawerLayout);
SetNativeControl(_nativeDrawerLayout);
}
private void AddContentLayer(DrawerLayout nativeDrawerLayout)
{
_contentView = new FormsElementWrapper(Element.MainContent);
nativeDrawerLayout.AddView(_contentView);
}
private void AddDrawerLayer(DrawerLayout nativeDrawerLayout)
{
_drawerView = new FormsElementWrapper(Element.DrawerContent);
UpdateDrawerLength();
nativeDrawerLayout.AddView(_drawerView);
}
private int GetDrawerGravity()
{
switch (Element.DrawerPosition)
{
case DrawerPosition.Left:
return (int)GravityFlags.Start;
case DrawerPosition.Right:
return (int)GravityFlags.End;
default:
throw new ArgumentOutOfRangeException();
}
}
protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
base.OnElementPropertyChanged(sender, e);
switch (e.PropertyName)
{
case nameof(Framework.Controls.SideDrawer.Height):
break;
case nameof(Framework.Controls.SideDrawer.Width):
break;
case nameof(Framework.Controls.SideDrawer.MainContent):
_contentView = new FormsElementWrapper(Element.MainContent);
break;
case nameof(Framework.Controls.SideDrawer.DrawerContent):
_drawerView = new FormsElementWrapper(Element.DrawerContent);
break;
case nameof(Framework.Controls.SideDrawer.IsOpen):
UpdateDrawerStateProgramatically();
break;
case nameof(Framework.Controls.SideDrawer.DrawerLength):
case nameof(Framework.Controls.SideDrawer.DrawerPosition):
UpdateDrawerLength();
break;
}
}
private void UpdateDrawerLength()
{
var layoutParamsDrawer = new DrawerLayout.LayoutParams(Element.DrawerLength, ViewGroup.LayoutParams.MatchParent);
layoutParamsDrawer.Gravity = GetDrawerGravity();
_drawerView.LayoutParameters = layoutParamsDrawer;
}
private void UpdateDrawerStateProgramatically()
{
if (Element.IsOpen)
{
Control.OpenDrawer(GetDrawerGravity());
}
else
{
Control.CloseDrawer(GetDrawerGravity());
}
}
public void OnDrawerClosed(View drawerView)
{
Element.IsOpen = false;
System.Diagnostics.Debug.WriteLine("OnDrawerClosed");
}
public void OnDrawerOpened(View drawerView)
{
Element.IsOpen = true;
System.Diagnostics.Debug.WriteLine("OnDrawerOpened");
}
public void OnDrawerSlide(View drawerView, float slideOffset)
{
switch (Element.DrawerPosition)
{
case DrawerPosition.Left:
_contentView.TranslationX = (int)Math.Abs(Element.DrawerLength * slideOffset);
break;
case DrawerPosition.Right:
_contentView.TranslationX = (int)Math.Abs(Element.DrawerLength * slideOffset) * -1;
break;
default:
throw new ArgumentOutOfRangeException();
}
_nativeDrawerLayout.BringChildToFront(_drawerView);
_nativeDrawerLayout.RequestLayout();
((ISideDrawerNativeEventProxy)Element)?.RaiseSlideChanged(slideOffset);
}
public void OnDrawerStateChanged(int newState)
{
}
}
}
Xamarin.Forms Control:
public enum DrawerPosition
{
Left,
Right
}
public interface ISideDrawerNativeEventProxy
{
void RaiseSlideChanged(float percentage);
}
public class SideDrawer : Grid, ISideDrawerNativeEventProxy
{
#region IsOpen
public static BindableProperty IsOpenProperty = BindableProperty.Create<SideDrawer, bool>(d => d.IsOpen, default(bool), defaultBindingMode: BindingMode.TwoWay);
public bool IsOpen
{
get { return (bool) GetValue(IsOpenProperty); }
set { SetValue(IsOpenProperty, value); }
}
#endregion IsOpen
#region DrawerPosition
public static BindableProperty DrawerPositionProperty = BindableProperty.Create<SideDrawer, DrawerPosition>(d => d.DrawerPosition, default(DrawerPosition));
public DrawerPosition DrawerPosition
{
get { return (DrawerPosition) GetValue(DrawerPositionProperty); }
set { SetValue(DrawerPositionProperty, value); }
}
#endregion DrawerPosition
public static BindableProperty MainContentProperty = BindableProperty.Create<SideDrawer, View>(d => d.MainContent, default(View), propertyChanging: MainContentPropertyChanging, propertyChanged: MainContentPropertyChanged);
private static void MainContentPropertyChanged(BindableObject bindable, View oldValue, View newValue)
{
if (newValue == null)
return;
newValue.Parent = (View)bindable;
}
private static void MainContentPropertyChanging(BindableObject bindable, View oldValue, View newValue)
{
if (oldValue == null)
return;
oldValue.Parent = null;
}
public View MainContent
{
get { return (View) GetValue(MainContentProperty); }
set { SetValue(MainContentProperty, value); }
}
public static BindableProperty DrawerContentProperty = BindableProperty.Create<SideDrawer, View>(d => d.DrawerContent, default(View), propertyChanging: DrawerContentPropertyChanging, propertyChanged: DrawerContentPropertyChanged);
private static void DrawerContentPropertyChanged(BindableObject bindable, View oldValue, View newValue)
{
if (newValue == null)
return;
newValue.Parent = (View)bindable;
}
private static void DrawerContentPropertyChanging(BindableObject bindable, View oldValue, View newValue)
{
if (oldValue == null)
return;
oldValue.Parent = null;
}
public View DrawerContent
{
get { return (View) GetValue(DrawerContentProperty); }
set { SetValue(DrawerContentProperty, value); }
}
#region DrawerLength
public static BindableProperty DrawerLengthProperty = BindableProperty.Create<SideDrawer, int>(d => d.DrawerLength, default(int), defaultValueCreator: DrawerLengthDefault);
private static int DrawerLengthDefault(SideDrawer bindable)
{
return 300;
}
public int DrawerLength
{
get { return (int) GetValue(DrawerLengthProperty); }
set { SetValue(DrawerLengthProperty, value); }
}
#endregion DrawerLength
#region IsContentTranslated
public static BindableProperty IsContentTranslatedProperty = BindableProperty.Create<SideDrawer, bool>(d => d.IsContentTranslated, true);
public bool IsContentTranslated
{
get { return (bool) GetValue(IsContentTranslatedProperty); }
set { SetValue(IsContentTranslatedProperty, value); }
}
#endregion IsContentTranslated
void ISideDrawerNativeEventProxy.RaiseSlideChanged(float percentage)
{
}
protected override void OnBindingContextChanged()
{
base.OnBindingContextChanged();
if (MainContent != null)
SetInheritedBindingContext(MainContent, BindingContext);
if (DrawerContent != null)
SetInheritedBindingContext(DrawerContent, BindingContext);
}
}
The major flaws in my original implementation were:
lack of measurement data being forwarded
not forwarding parent hierarchy
not inheriting bindingcontext

Create a hierarchy custom server control

I have a self-referencing table and I want to visualize it using:
<ol>
<li>
</li>
</ol>
I want to create a custom server data-bound control with templates, I have read the MSDN article:
http://msdn.microsoft.com/en-us/library/aa479322.aspx
But I think that, I have to use different aproach and inherit the
HierarchicalDataBoundControl
or implement
IHierarchicalDataSource
But I cannot find any examples, or something to read from.
Can someone point me to a book or an article, or explain it to me in steps how it needs to be done.
A summary of what is required is this:
A Control which extends HierarchicalDataSourceControl AND DataSourceControl that implements IHeirarchicalDataSource. Believe me working from the documentation provided took A LOT of trial and error but in the end it is worth it. Mines been on hold but shortly I'll complete a project using this which will be able to bind to any n depth structure + navigate it in code using Node.GetParent().GetChildren().Where .. etc. It's complicted and may be overkill for what you need and you may revert back to repeater. Given the posting length allowed at stackoverflow I can't give you full code listing (some 100k chars)
To give you a flavour of whats in my other code here is the generic IHierachicalDataSourceControl:
#region Generic Hierachical DatasourceControl
/// <summary>
/// Datasource control
/// </summary>
public class GenericHierachicalDataSourceControl<TDataContext, TNode, TEntity> : HierarchicalDataSourceControl, IHierarchicalDataSource
where TDataContext : DataContext, new()
where TNode : class,PNS.GenericLinqNodeHeirachy<TDataContext, TNode, TEntity>.IHeirachicalNode, new()
where TEntity : class,PNS.GenericLinqNodeHeirachy<TDataContext, TNode, TEntity>.IHeirachyNodeEntity, new()
{
NodeDataSourceView view;
protected override HierarchicalDataSourceView GetHierarchicalView(string viewPath)
{
view = new NodeDataSourceView(viewPath);
return view;
}
public class NodeDataSourceView : HierarchicalDataSourceView
{
private string _viewPath;
public NodeDataSourceView(string viewPath)
{
_viewPath = viewPath;
}
public override IHierarchicalEnumerable Select()
{
var hierarchy = new HierarchicalEnumerable();
List<TNode> topNodes;
if (String.IsNullOrEmpty(_viewPath))
{
//get all top level nodes (ones without parents)
topNodes = GenericLinqNodeHeirachy<TDataContext, TNode, TEntity>.NodesDAL.GetTopLevelNodes().ToList();
}
else
{
//get the last node in the path
string[] nodes = _viewPath.Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
topNodes = new List<TNode>();
topNodes.Add(GenericLinqNodeHeirachy<TDataContext, TNode, TEntity>.NodesDAL.GetNode(nodes[nodes.Length - 1]));
}
//for each node in the path
foreach (var node in topNodes)
{
if (node.Entity != null)
{
hierarchy.Add(node.Entity);
}
}
return hierarchy;
}
}
public class HierarchicalEnumerable : List<TEntity>, IHierarchicalEnumerable
{
public HierarchicalEnumerable()
: base()
{
}
public IHierarchyData GetHierarchyData(object enumeratedItem)
{
return enumeratedItem as IHierarchyData;
}
}
}
and another part:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI.WebControls;
using System.Web.UI;
using System.Web.UI.HtmlControls;
namespace BootstrapProject.CodeBase
{
public class GenericHierarchicalDataboundControl : HierarchicalDataBoundControl
{
private string _textField;
public string TextField
{
get { return _textField; }
set { _textField = value; }
}
protected override string TagName
{
get
{
return "div";
}
}
protected override HtmlTextWriterTag TagKey
{
get
{
return HtmlTextWriterTag.Div;
}
}
protected override void CreateChildControls()
{
if (null != Page && Page.IsPostBack && null != ViewState["_!DataBound"])
{
this.RequiresDataBinding = true;
this.EnsureDataBound();
}
}
protected override void PerformDataBinding()
{
IHierarchicalEnumerable dataSource = GetData(string.Empty).Select();
this.PerformDataBinding(0, this.Controls, dataSource);
this.MarkAsDataBound();
}
protected virtual void PerformDataBinding(int level, ControlCollection controls, IHierarchicalEnumerable dataSource)
{
if (null != dataSource)
{
//controls.Clear();
HtmlGenericControl ul = new HtmlGenericControl("ul");
foreach (object value in dataSource)
{
var itemData = dataSource.GetHierarchyData(value);
Control item = CreateAndBindControl(level, value);
ul.Controls.Add(item);
var data = dataSource.GetHierarchyData(value);
if (data != null && data.HasChildren)
{
IHierarchicalEnumerable childData = data.GetChildren();
PerformDataBinding(1 + level, item.Controls, childData);
}
controls.Add(ul);
}
}
}
protected virtual Control CreateAndBindControl(int level, object dataItem)
{
HtmlGenericControl li = new HtmlGenericControl("li");
string text = String.Empty;
if (!String.IsNullOrEmpty(TextField))
{
text = DataBinder.GetPropertyValue(dataItem, TextField).ToString();
}
else
{
text = dataItem.ToString();
}
li.Attributes.Add("rel", text);
li.Controls.Add(new HyperLink { Text = text });
return li;
}
}
}
And finally:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using BootstrapProject.CodeBase.DAL;
using PNS;
namespace BootstrapProject.CodeBase
{
public class NodeDataSourceControl : HierarchicalDataSourceControl, IHierarchicalDataSource
{
NodeDataSourceView view;
protected override HierarchicalDataSourceView GetHierarchicalView(string viewPath)
{
view = new NodeDataSourceView(viewPath);
return view;
}
}
public class NodeDataSourceView : HierarchicalDataSourceView
{
private string _viewPath;
public NodeDataSourceView(string viewPath)
{
_viewPath = viewPath;
}
public override IHierarchicalEnumerable Select()
{
var hierarchy = new CMSPageHierarchicalEnumerable();
List<DAL.Node> topNodes;
if (String.IsNullOrEmpty(_viewPath))
{
//get all top level nodes (ones without parents)
topNodes = CMS.NodesDAL.GetTopLevelNodes().ToList();
}
else
{
//get the last node in the path
string[] nodes = _viewPath.Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
topNodes = new List<DAL.Node>();
topNodes.AddRange(CMS.NodesDAL.GetNode(nodes[nodes.Length - 1]).NodeChildren);
}
//for each node in the path
foreach (var node in topNodes)
{
if (node.Page != null)
{
hierarchy.Add(node.Page);
}
}
return hierarchy;
}
}
}

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