Jon, Given that this is a general stream-related issue, could it be causing the random issues I've seen around HttpWebRequests? (http://bugzilla.xamarin.com/show_bug.cgi?id=1031)
Thanks, Andy -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jonathan Pryor Sent: 29 September 2011 22:23 To: Discussions related to Mono for Android Subject: Re: [mono-android] Trouble with Android.Graphics Short version: http://stackoverflow.com/questions/7535503/mono-for-android-exit-code-255-on -bitmapfactory-decodestream/7590929#7590929 Long version: We map every Java method which takes e.g. java.io.InputStream to a System.IO.Stream, and provide an "Adapter" which subclasses System.IO.Stream and invokes the corresponding InputStream methods. Ditto for OutputStream, etc. However, one thing we didn't realize until this week is that Java and C# have different conventions for "end-of-stream" (EOS) -- Java uses -1, while C# uses 0. So what would frequently happen (such as your test cases) is that you'd call the bound method, which would return a Stream, and then invoke another Java method. This would result in e.g. BitmapDrawable.createFromStream() doing a Java->Managed->Java transition for the .read() method, and because of the "mismatch" of EOS conventions, things would go "weird" (e.g. the Java stream would return 0, which C# code would interpret as EOS, when it actually meant "no data right now, try again later.") This will be fixed in the 1.9.1 release. In the meantime, try going through a MemoryStream + byte[], as I suggest in the above stack overflow answer. - Jon On Sep 29, 2011, at 12:30 PM, John Heerman wrote: > Hello, > > I've run across a problem trying to retrieve an image from the web and > decode the stream or byte array into a bitmap/drawable resource. Each > one of the tests below fail when I try to invoke the static > BitmapFactory or BitmapDrawable class. I'm running my tests in > MonoDevelop on Mac OSX Lion targeting API Level 8 with Mono for > Android 1.2. > > The exception I receive for test 1: > System.NullReferenceException: Object reference not set to an instance > of an object > at Android.Runtime.JNIEnv.get_Handle () [0x00014] in > /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:33 > at Android.Runtime.JNIEnv.get_Env () [0x00000] in /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:24 > at Android.Runtime.JNIEnv.FindClass (System.String classname) > [0x00000] in /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:145 > at Android.Graphics.BitmapFactory..cctor () [0x00000] in <filename unknown>:0 > > > The exception I receive for test 2: > System.NullReferenceException: Object reference not set to an instance > of an object > at Android.Runtime.JNIEnv.get_Handle () [0x00014] in > /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:33 > at Android.Runtime.JNIEnv.get_Env () [0x00000] in /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:24 > at Android.Runtime.JNIEnv.FindClass (System.String classname) > [0x00000] in /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:145 > at Android.Graphics.BitmapFactory..cctor () [0x00000] in <filename unknown>:0 > > The exception I receive for test 3: > System.NullReferenceException: Object reference not set to an instance > of an object > at Android.Runtime.JNIEnv.get_Handle () [0x00014] in > /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:33 > at Android.Runtime.JNIEnv.get_Env () [0x00000] in /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:24 > at Android.Runtime.JNIEnv.FindClass (System.String classname) > [0x00000] in /Volumes/Macintosh > HD/Users/jon/Development/xamarin/monodroid/Mono.Android/src/Runtime/JNIEnv.c s:145 > at Android.Graphics.Drawables.Drawable..cctor () [0x00000] in > <filename unknown>:0 > > Any help would be greatly appreciated. > > Regards, > John > > ////////////////////////////////////////////////////////// > > using System; > using System.Net; > > using Android.Graphics; > using Android.Graphics.Drawables; > > using NUnit.Framework; > > namespace App.Shared.Test > { > [TestFixture] > public class ImageTest > { > private string url = > "http://www.google.com/intl/en_com/images/srpr/logo3w.png";; > > [Test] > public void TestStreamWithBitmapFactory() > { > try > { > System.IO.Stream stream = new WebClient().OpenRead(url); > var bitmap = BitmapFactory.DecodeStream(stream); > Assert.IsNotNull(bitmap); > } > catch (Exception ex) > { > Console.WriteLine(ex.InnerException); > Assert.Fail(ex.InnerException.ToString()); > } > > } > > [Test] > public void TestBytesWithBitmapFactory() > { > try > { > byte[] bytes = new WebClient().DownloadData(url); > var bitmap = BitmapFactory.DecodeByteArray(bytes, 0, bytes.Length); > Assert.IsNotNull(bitmap); > } > catch (Exception ex) > { > Console.WriteLine(ex.InnerException); > Assert.Fail(ex.InnerException.ToString()); > } > } > > [Test] > public void TestStreamWithBitmapDrawable() > { > try > { > System.IO.Stream stream = new WebClient().OpenRead(url); > var bitmap = BitmapDrawable.CreateFromStream(stream, "src"); > Assert.IsNotNull(bitmap); > } > catch (Exception ex) > { > Console.WriteLine(ex.InnerException); > Assert.Fail(ex.InnerException.ToString()); > } > } > } > } > _______________________________________________ > Monodroid mailing list > [email protected] > > UNSUBSCRIBE INFORMATION: > http://lists.ximian.com/mailman/listinfo/monodroid _______________________________________________ Monodroid mailing list [email protected] UNSUBSCRIBE INFORMATION: http://lists.ximian.com/mailman/listinfo/monodroid _______________________________________________ Monodroid mailing list [email protected] UNSUBSCRIBE INFORMATION: http://lists.ximian.com/mailman/listinfo/monodroid
![http://www.google.com/intl/en_com/images/srpr/logo3w.png"](https://www.google.com/intl/en_com/images/srpr/logo3w.png"){kind=link}