Question

I’m using Visual Studio 2010 and the Mono Droid v1.0.1 to begin programming in C # for the Android platform.

I have a problem. From the main Activity want to call another activty (‘prueba’), it does well, but I do not show anything on the screen. That is, show me a new screen with the title ‘prueba’ but did not show anything in it (it’s all in black).

This is the code I’m using:

• AndroidManifest.xml

   <?xml version="1.0" encoding="utf-8"?>
       <manifest xmlns:android="http://schemas.android.com/apk/res/android"   android:installLocation="internalOnly" package="MonoAndroidApplication1.MonoAndroidApplication1.apk" android:versionCode="1" android:versionName="Primera">
  
  <application android:label="MonoAndroidApplication1">
  </application>
  <uses-sdk android:minSdkVersion="4" />
  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
  <activity android:name=".Prueba" />
  </manifest>
  

• Activity1.cs

  using System;
  using Android.App;
  using Android.Content;
  using Android.Runtime;
  using Android.Views;
  using Android.Widget;
  using Android.OS;
  using System.IO;
  
  namespace MonoAndroidApplication1
  {
  
   [Activity(Label = "MonoAndroidApplication1", MainLauncher = true, Icon = "@drawable/icon")]
  
  public class Activity1 : Activity
  {
      EditText et01;
      EditText et02;
      EditText et03;
  
      Button bt01;
      Button bt02;
      Button bt03;
  
      protected override void OnCreate(Bundle bundle)
      {
          base.OnCreate(bundle);
  
          SetContentView(Resource.Layout.Main);
  
          et01 = (EditText)FindViewById(Resource.Id.edittext01);
          et02 = (EditText)FindViewById(Resource.Id.edittext02);
          et03 = (EditText)FindViewById(Resource.Id.edittext03);
          bt01 = (Button)FindViewById(Resource.Id.button01);
          bt02 = (Button)FindViewById(Resource.Id.button02);
          bt03 = (Button)FindViewById(Resource.Id.button03);
  
          bt01.Click += (sender, e) =>
          {
              et01.Text = string.Format("Click en 1");
          };
          bt02.Click += (sender, e) =>
          {
              et02.Text = string.Format("Click en 2");
          };
          bt03.Click += (sender, e) =>
          {
              et03.Text = string.Format("Click en 3");
              Intent i = new Intent(this, typeof(Prueba));
              StartActivity(i);
          };
  
          Toast.MakeText(this, "Esto es un ejemplo", ToastLength.Short).Show();
       }
     }
   }
  

• Prueba.cs

  using System;
  using Android.App;
  using Android.Content;
  using Android.Runtime;
  using Android.Views;
  using Android.Widget;
  using Android.OS;
  using System.IO;
  
  namespace MonoAndroidApplication1
  {
      [Activity(Label = "Prueba", MainLauncher = true, Icon = "@drawable/icon")]
      public class Prueba : Activity
      {
          public void onCreate(Bundle savedInstanceState)
          {
               SetContentView(Resource.Layout.Prueba);
          }
      }
   }
  

• Prueba.axml

  <?xml version="1.0" encoding="utf-8"?>
  <AbsoluteLayout
   android:id="@+id/widget0"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   xmlns:android="http://schemas.android.com/apk/res/android"
  >
    <TextView
         android:id="@+id/textoif"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="IF-Software"
   >
  </TextView>
  

• Main.axml

   <?xml version="1.0" encoding="utf-8"?>
   <TableLayout
    android:id="@+id/widget27"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
   >
     <TableRow
      android:id="@+id/widget28"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="horizontal"
     >
       <TextView
        android:id="@+id/widget32"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Prueba IF"
       >
       </TextView>
     </TableRow>
     <TableRow
      android:id="@+id/widget29"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="horizontal"
     >
       <EditText
        android:id="@+id/edittext01"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="18sp"
       >
      </EditText>
      <Button
       android:id="@+id/button01"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="1"
      >
      </Button>
    </TableRow>
    <TableRow
     android:id="@+id/widget30"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="horizontal"
    >
      <EditText
       android:id="@+id/edittext02"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:textSize="18sp"
      >
      </EditText>
      <Button
       android:id="@+id/button02"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="2"
      >
      </Button>
    </TableRow>
    <TableRow
     android:id="@+id/widget31"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="horizontal"
    >
      <EditText
       android:id="@+id/edittext03"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:textSize="18sp"
     >
     </EditText>
     <Button
      android:id="@+id/button03"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:text="3"
     >
     </Button>
   </TableRow>
  </TableLayout>
  

Answer 1

Not a MonoDroid developer, but I do notice that your missing the “override” keyword on the second activity onCreate and also not calling the parent.