Best Of

Re: Is it possible to make a multiple commands in single custom control?

custom control Xaml

       <Button x:Name="button1" Text="11111"  />
        <Button x:Name="button2" Text="22222"  />

custom control code

    public static readonly BindableProperty Command1Property =
        BindableProperty.Create(propertyName: nameof(Command1),
                            returnType: typeof(ICommand),
                            declaringType: typeof(View1),
                            defaultValue: default(ICommand),
                            propertyChanged:(bindable, oldValue, newValue)=> {
                if (bindable is View1 v && newValue is ICommand command)
                {
                     v.button1.Command = command;
                }
            });

    public ICommand Command1
    {
        get { return (ICommand)GetValue(Command1Property); }
        set { SetValue(Command1Property, value); }
    }


    public static readonly BindableProperty Command2Property =
        BindableProperty.Create(propertyName: nameof(Command2),
                            returnType: typeof(ICommand),
                            declaringType: typeof(View1),
                            defaultValue: default(ICommand),
                            propertyChanged: (bindable, oldValue, newValue) => {
                                if (bindable is View1 v && newValue is ICommand command)
                                {
                                    v.button2.Command = command;
                                }
                            });

    public ICommand Command2
    {
        get { return (ICommand)GetValue(Command2Property); }
        set { SetValue(Command2Property, value); }
    }

Model

public class Model
{

    public ICommand c1 { get; set; }

    public ICommand c2 { get; set; }

    public Model()
    {
        c1 = new Command(() => {

        });

        c2 = new Command(() => {

        });
    }
}

Page

  public Page()
    {
        InitializeComponent();
        Model model = new Model();                  
        this.BindingContext = model;
    }

ColeX

Re: correct usage of storyboard in iOS Designer

The error is because there are actually three places in the Info.plist that reference Main.storyboard, but changing the Main Interface value in the Application page of the Info.plist only changes one of them.

Try this from a new Single View App template:

Delete Main.storyboard
Delete ViewController.cs and ViewController.designer.cs files
Right click on project in Solution Explorer and select Add -> New File...
Select iOS -> Storyboard, enter desired name (I'll use NewStoryboard for this example) , and click "New" button
Open Info.plist file and enter NewStoryboard in the Main Interface field.
Select the Source tab at the bottom of the Info.plist.
If there is a "Main Storyboard file base name (iPad)" entry, change the value to NewStoryboard <--- this does not get changed when change Main Interface field in step 5
Expand the UIApplicationSceneManifest entry
Drill down until you find UISceneStoryboardFile entry and change value that to NewStoryboard <--- this does not get changed when change Main Interface field in step 5
Open NewStoryboard in the iOS Designer
Open the Toolbox panel (Visual Studio for Mac menu View > Pads > Toolbox)
Drag a ViewController onto the canvas
Open the Properties panel (Visual Studio fro Mac menu View > Pads > Properties)
Select the ViewController by clicking on the bottom rectangle of the ViewController on the canvas
In the Properties panel, enter the name of the class you want for that ViewController in the Class field, let's call it InitialViewController, and hit Return/Enter
A new class should be added to your project called InitialViewController.
Now everything should be connected just as in a new project.

As for XIB's, I would avoid them. They are deprecated.

JGoldberger

Re: Is there any way to open a web page synchronously?

@LandLu said:
This is mostly like an authentication process so it could be achieved. Use the code below to open your webpage in browser:
Device.OpenUri(new Uri("Your Uri"));
Then we could return to the project through the app link:
https://github.com/xamarin/docs-archive/tree/master/Recipes/cross-platform/app-links

Don't forget that Device.OpenUri has been deprecated.

The recommended replacement is:

                if (await Xamarin.Essentials.Launcher.CanOpenAsync(uri))
                    await Xamarin.Essentials.Launcher.OpenAsync(uri);

JohnHardman

Re: Stop toasts displaying when my app is in the background

You solution is good, you could create a ToastUtils for your application as well.

public  class ToastUtils
{
    private static Toast mToast, mToastNormal;
    private static View view;


    public static void showNOrmalToast(Context mContext, String message)
    {

        ToastUtils.cancel();

        if (mToastNormal == null)
        {
            mToastNormal = Toast.MakeText(mContext, message, ToastLength.Long);
        }

        mToastNormal.Show();

    }
    /**
    *cancel toast
    */
    public static void cancel()
    {

        if (mToast != null)
        {
            mToast.Cancel();
            mToast = null;
        }

    }

}

Then you can add the cancel method in your OnPause.

 protected override void OnPause()
    {

       base.OnPause();
        ToastUtils.cancel();
    }

You can add isActivityRunning to check if whether the application is currently on the top of the task stack to determine whether to display it

    public static bool isActivityRunning(string packagename, Context context)
    {
        ActivityManager am = (ActivityManager)context.GetSystemService(Context.ActivityService);
        IList<RunningTaskInfo> runningTaskInfos = am.GetRunningTasks(1);
        string cmpNameTemp = null;
        if (null != runningTaskInfos)
        {
            cmpNameTemp = runningTaskInfos[0].TopActivity.ToString();
        }
        if (null != cmpNameTemp)
        {
            return cmpNameTemp.Contains(packagename);
        }
        return false;
    }

Before you want to show the Toast, you can check it.

 public  class ToastUtils
{
    private static Toast mToast, mToastNormal;
    private static View view;

    public static bool isActivityRunning(string packagename, Context context)
    {
        ActivityManager am = (ActivityManager)context.GetSystemService(Context.ActivityService);
        IList<RunningTaskInfo> runningTaskInfos = am.GetRunningTasks(1);
        string cmpNameTemp = null;
        if (null != runningTaskInfos)
        {
            cmpNameTemp = runningTaskInfos[0].TopActivity.ToString();
        }
        if (null != cmpNameTemp)
        {
            return cmpNameTemp.Contains(packagename);
        }
        return false;
    }

    public static void showNOrmalToast(Context mContext, String message)
    {

       ToastUtils.cancel();

        if (mToastNormal == null)
        {
            mToastNormal = Toast.MakeText(mContext, message, ToastLength.Long);
        }

        if (isActivityRunning(mContext.PackageName, mContext))
        {
            mToastNormal.Show();
        }


    }
    /**
    *cancel toast
    */
    public static void cancel()
    {

        if (mToast != null)
        {
            mToast.Cancel();
            mToast = null;
        }

    }

}

LeonLu

Re: How to add square border to image in xamarin froms.

I don't know if you're still working on this since it's about 40 days old,

but for future people, if you have that visual issue of a small frame having content that isn't being displayed, change the padding of the frame to 0 and check again. Frames have a default padding of 20, so if the frame is only being given a 40x40 slot, nothing will show. If the frame is given a 60x50 slot, you are giving the content within the frame a 20x10 spot, when it most likely needs more than that.

Just change the padding to 0 and see if it works. If it does, then play around with the padding til you find the amount that looks good while still giving it's content enough real estate.

SunliMin

Re: xamarin android / ios icons pack - where to get?

As there is so many policies about trademark so is there any place where we can generate new icons?

Are you looking for https://www.iconsgenerator.com/?

ColeX

Re: Xamarin forms: Device.OpenUri is not working for opening pdf in iPhone.

OpenUri method opens safari on iOS , but safari blocks the insecure websites , we could use Webview to show online pdf , if problem persists , enable your domain in info.plist ,refer iOS and ATS .

<key>NSAppTransportSecurity</key>
    <dict>
        <key>NSExceptionDomains</key>
        <dict>
            <key>xamarin.com</key>
            <dict>
                <key>NSIncludesSubdomains</key>
                <true/>
                <key>NSTemporaryExceptionAllowsInsecureHTTPLoads</key>
                <true/>
                <key>NSTemporaryExceptionMinimumTLSVersion</key>
                <string>TLSv1.1</string>
            </dict>
        </dict>
    </dict>
</key>

For android part, you could still call OpenUri to show pdf .

if(Device.RuntimePlatform == Device.iOS){
    webview.Source = "https://d1kv7s9g8y3npv.cloudfront.net/cbrain-app/files/doc-lib/2018/02/15/04/38/50/084/head/Catechism Lesson 6 Fill-in-the-Blanks.pdf"
}
if(Device.RuntimePlatform == Device.Android){
    Device.OpenUri(new Uri("https://d1kv7s9g8y3npv.cloudfront.net/cbrain-app/files/doc-lib/2018/02/15/04/38/50/084/head/Catechism Lesson 6 Fill-in-the-Blanks.pdf"));
}

ColeX

Re: How to call function from web api in xamarin froms

I simple use this:

var httpClient = new HttpClient();
var response = httpClient.GetStringAsync(<URL>).GetAwaiter().GetResult();

Object = JsonConvert.DeserializeObject<Object >(response);

MarcDieters

Re: How to call function from web api in xamarin froms

First , ensure that the string returned web service should be valid json formatting , just like

[
{
"CategoryName ": 1,
"PartnerName ": "cole1",
"Zip ": "123",
"City": "NewYork",
},
{
"CategoryName ": 2,
"PartnerName ": "cole2",
"Zip ": "test2",
"City": "San Francisco",
},
//xxx
]

Then Generate model class according to your json string , you could use this website.

public class Prts
    {
        [JsonProperty("CategoryName")]
        public string CategoryName { get; set; }
        [JsonProperty("PartnerName")]
        public string PartnerName { get; set; }
        [JsonProperty("Zip")]
        public string Zip { get; set; }
        [JsonProperty("City")]
        public string City { get; set; }
    }

Last , consume RESTful api and Retrieve Data

public async Task<List<TodoItem>> RefreshDataAsync ()
{
  ...
  var uri = new Uri (string.Format (Constants.TodoItemsUrl, string.Empty));
  ...
  var response = await _client.GetAsync (uri);
  if (response.IsSuccessStatusCode)
  {
      var content = await response.Content.ReadAsStringAsync ();
      Items = JsonConvert.DeserializeObject <List<TodoItem>> (content);
  }
  ...
}

Check my answer: https://forums.xamarin.com/discussion/comment/396211/#Comment_396211

ColeX

Re: How to Show a progress bar in Local Notification in xamarin IOS?

We need UserNotificationsUI .

Add a Notification Content Extension (new to iOS 10) to the app's solution.
Drag custom view(progress) onto Stroyboard in the extension .
Set the Notification Content Extension's categories in info.plist .

Display content and write callback in the method DidReceiveNotification .

public void DidReceiveNotification (UNNotification notification)
{
    label.Text = notification.Request.Content.Body;

    // Grab content
    var content = notification.Request.Content;

    // Display content in the UILabels
    EventTitle.Text = content.Title;
    EventDate.Text = content.Subtitle;
    EventMessage.Text = content.Body;

    // Get location and display
    var location = content.UserInfo ["location"].ToString ();
    if (location != null) {
        Event.Location.Text = location;
    }
 }

Details refer https://docs.microsoft.com/en-us/xamarin/ios/platform/user-notifications/advanced-user-notifications?tabs=windows .

ColeX