Pass Objects between Activities

Heinz Wäscher 1 Reputation point
2021-07-03T08:50:38.147+00:00

Good morning,

I have two Activities and would like to pass an object instance between them.
The object is of type WebDavClient from a nugetpacket.

// Activity a:
Intent intent = new Intent(this, typeof(NewAcivity));
intent.PutExtra("Client", JsonConvert.SerializeObject(client));

// Activity b:
client = JsonConvert.DeserializeObject<WebDavClient>(Intent.GetStringExtra("Client"));

Am I on the wrong track in general or does it only not work with this object?
How else can objects be passed?
Via the class Intent?

Many thanks for your help.

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Xamarin
Xamarin
A Microsoft open-source app platform for building Android and iOS apps with .NET and C#.
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  1. JarvanZhang 23,936 Reputation points
    2021-07-07T08:48:44.697+00:00

    Hello,​

    Welcome to our Microsoft Q&A platform!

    1.Try using a custom object class as the tranfer parameter. Here the sample code, please check:

       //Activity1  
       Intent intent = new Intent(this, typeof(Activity1));  
       TestModel model = new TestModel { Name = "test_name" };  
       intent.PutExtra("model", JsonConvert.SerializeObject(model));  
       StartActivity(intent);  
    
       //Activity2  
       var model = JsonConvert.DeserializeObject<TestModel>(Intent.GetStringExtra("model"));  
       string text = model.Name;  
    
       //the model class  
       public class TestModel  
       {  
           public TestModel()  
           {  
           }  
           public string Name { get; set; }  
       }  
    

    If the above code works well, the issue should be due to the 'WebDavClient'.

    2.To share the client between activities, you could also create a global variable of the application. Create a custom Application class for the project and add a parameter in the custom class.

       [Application]  
       public class CustomApplication : Application  
       {  
           protected CustomApplication(IntPtr javaReference, JniHandleOwnership transfer) : base(javaReference, transfer)  
           {  
           }  
    
           public static TestModel TheModel = new TestModel();  
       }  
    
       //set the `android:name` to the custom application class  
       <manifest ...>  
         <application android:name=".CustomApplication" ...>  
         </application>  
       </manifest>  
    
    
       //Activity1  
       var model = CustomApplication.TheModel;  
       model.Name = "testing...";  
       StartActivity(new Intent(this, typeof(Activity1)));  
    
       //Activity2  
       string text = CustomApplication.TheModel.Name;  
    

    Best Regards,

    Jarvan Zhang


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