can not get the android binding?

Question

can not get the android binding?

mc 5,796

I am using .net android and I want to use the zxing-android-embeded.aar but there is something wrong:

CS1503 can not convert Com.Journeyapps.Barcodescanner.Camera.CameraThread to Android.Runtime.IJavaObject

protected virtual unsafe global::Com.Journeyapps.Barcodescanner.Camera.CameraThread? CameraThread {
	// Metadata.xml XPath method reference: path="/api/package[@name='com.journeyapps.barcodescanner.camera']/class[@name='CameraInstance']/method[@name='getCameraThread' and count(parameter)=0]"
	[Register ("getCameraThread", "()Lcom/journeyapps/barcodescanner/camera/CameraThread;", "GetGetCameraThreadHandler")]
	get {
		const string __id = "getCameraThread.()Lcom/journeyapps/barcodescanner/camera/CameraThread;";
		try {
			var __rm = _members.InstanceMethods.InvokeVirtualObjectMethod (__id, this, null);
			return global::Java.Lang.Object.GetObject<global::Com.Journeyapps.Barcodescanner.Camera.CameraThread> (__rm.Handle, JniHandleOwnership.TransferLocalRef);
		} finally {
		}
	}
}

1 answer

Your answer

Answer 1

Thank you for reaching out. Please find the answer below this.

Xamarin.Android Binding Fix for CameraThread (CS1503)

What’s Breaking

Binding generator gave getCameraThread() the wrong managed return type (defaulted to Java.Lang.Object), causing:

CS1503: Cannot convert from CameraThread to IJavaObject

Where to Look

obj/<Config>/api.xml → Find CameraInstance.getCameraThread. If it doesn’t return CameraThread, that’s the issue.
Transforms/Metadata.xml → This is where you fix it.

What to Change (Minimum Fix)

Paste this into your Metadata.xml:

<metadata>
  <attr
    path="/api/package[@name='com.journeyapps.barcodescanner.camera']
          /class[@name='CameraInstance']
          /method[@name='getCameraThread' and count(parameter)=0]"
    name="managedReturn">
    Com.Journeyapps.Barcodescanner.Camera.CameraThread
  </attr>
</metadata>

Quick Verify

Rebuild the binding.
Generated C# should use:

Java.Lang.Object.GetObject<CameraThread>(result.Handle, JniHandleOwnership.TransferLocalRef);

Property type should be CameraThread everywhere.

If Still Stuck

Ensure all AAR/JAR dependencies are included. Missing deps force fallback to Object.
Turn on MSBuild diagnostics:

msbuild /v:diag

Diff api.xml between Debug and Release for signature drift.

Temporary Workaround

Use manual materialization until the binding is fixed:

Java.Lang.Object.GetObject<CameraThread>(result.Handle, JniHandleOwnership.TransferLocalRef);

References

Let me know if you need any further help with this. We'll be happy to assist. If you find this helpful, please mark this as answered.

Share via

can not get the android binding?

1 answer

Your answer