无法从源类型转换为目标类型(JNIEnv.GetArray(pudis.Handle);)
作者：互联网
我想在我的应用程序中接收短信.
我的项目中有一个BroadcastReceiver类,我收到一个运行时错误：
System.InvalidCastException: Cannot cast from source type to
destination type. at at (wrapper castclass)
object.__castclass_with_cache (object,intptr,intptr) at at Android.Runtime.JNIEnv.CopyArray
(intptr,Java.Lang.Object[]) <0x002a3> at at
Android.Runtime.JNIEnv.GetArray (intptr) <0x0021f>
at Messages.SMSBroadcastReceiver.OnReceive
(Android.Content.Context,Android.Content.Intent) [0x0005f] in
c:\Users\Jase\Documents\Projects\Messages\Messages\SMSBroadcastReceiver.cs:36
at
Android.Content.BroadcastReceiver.n_OnReceive_Landroid_content_Context_Landroid_content_Intent_
(intptr,intptr,intptr,intptr) [0x00019] in
/Users/builder/data/lanes/monodroid-mlion-monodroid-4.20-series/ba9bbbdd/source/monodroid/src/Mono.Android/platforms/android-21/src/generated/Android.Content.BroadcastReceiver.cs:334
at at (wrapper dynamic-method)
object.145a0c82-0de6-4c2c-90a0-3654436a06c3
(intptr,intptr,intptr,intptr)
这是我正在使用的代码：
using System;
using System.Text;
using Android.App;
using Android.OS;
using Android.Content;
using Android.Runtime;
using Android.Util;
using Android.Widget;
using Android.Telephony;
using Environment = System.Environment;
namespace Messages
{
[BroadcastReceiver(Enabled = true, Label = "SMS Receiver")]
[IntentFilter(new[] { "android.provider.Telephony.SMS_RECEIVED" })]
public class SMSBroadcastReceiver : BroadcastReceiver
{
private const string Tag = "SMSBroadcastReceiver";
private const string IntentAction = "android.provider.Telephony.SMS_RECEIVED";
public override void OnReceive(Context context, Intent intent)
{
Log.Info(Tag, "Intent: " + intent.Action);
if (intent.Action != IntentAction)
return;
var bundle = intent.Extras;
if (bundle == null)
return;
var pdus = bundle.Get("pdus");
// ********** This is the error line at runtime ****************
var castedPdus = JNIEnv.GetArray<Java.Lang.Object>(pdus.Handle);
var messages = new SmsMessage[castedPdus.Length];
var stringBuilder = new StringBuilder();
for (int i = 0; i < messages.Length; i++)
{
var bytes = new byte[JNIEnv.GetArrayLength(castedPdus[i].Handle)];
JNIEnv.CopyArray(castedPdus[i].Handle, bytes);
messages[i] = SmsMessage.CreateFromPdu(bytes);
stringBuilder.Append(String.Format("SMS from: {0}{1}Body: {2}{1}", messages[i].OriginatingAddress,
Environment.NewLine, messages[i].MessageBody));
}
Toast.MakeText(context, stringBuilder.ToString(), ToastLength.Long).Show();
}
}
}
我一直试图找到一段时间的解决方案并且已经搜索了几个小时但是这个错误的现有解决方案都没有奏效.我不明白.有人可以帮忙解释一下吗？
我正在用以下内容更新此问题：
Bundle not null: Bundle[mParcelledData.dataSize=256]
PDUS: [[B@5s294833
PDUS Handle: 2065454
Cannot cast from source type to destination type. at (wrapper castclass) object:__castclass_with_cache (object,intptr,intptr)
at Android.Runtime.JNIEnv.CopyArray[Object] (IntPtr src, Java.Lang.Object[] dest) [0x00078] in /Users/builder/data/lanes/monodroid-mlion-monodroid-4.20-series/ba9bbbdd/source/monodroid/src/Mono.Android/src/Runtime/JNIEnv.cs:946
at Android.Runtime.JNIEnv.GetArray[Object] (IntPtr array_ptr) [0x00053] in /Users/builder/data/lanes/monodroid-mlion-monodroid-4.20-series/ba9bbbdd/source/monodroid/src/Mono.Android/src/Runtime/JNIEnv.cs:1211
at Java.Lang.Object.ToArray[Object] () [0x00000] in /Users/builder/data/lanes/monodroid-mlion-monodroid-4.20-series/ba9bbbdd/source/monodroid/src/Mono.Android/src/Java.Lang/Object.cs:338
at Java.Lang.Object.op_Explicit (Java.Lang.Object value) [0x00008] in /Users/builder/data/lanes/monodroid-mlion-monodroid-4.20-series/ba9bbbdd/source/monodroid/src/Mono.Android/src/Java.Lang/Object.cs:499
at Messages.SMSBroadcastReceiver.OnReceive (Android.Content.Context context, Android.Content.Intent intent) [0x000ba] in c:\Users\Jase\Documents\Projects\Messages\Messages\SMSBroadcastReceiver.cs:52
我还想指出,我已经尝试了很多方法来解决这个问题.我现在(真的)在谷歌的搜索结果的第60页,试图找到一些东西.问题是,我在网上找到的这个完全相同的错误的解决方案实际上都不起作用,因为它们基本上只是同一语句的微小变化,只是以稍微不同的方式编写,但做同样的事情会产生相同的异常.
我也尝试过以下方法：
// var castedPdus = JNIEnv.GetObjectArrayElement(pdus.Handle, 0);
// Object castedPdus = (Object)bundle.Get("pdus");
// var castedPdus = JNIEnv.GetArray<Java.Lang.Object>(pdus.Handle);
没有运气.
根据我使用的语句,异常从“无法从源类型转换为目标类型”到“无法将对象[]转换为对象”.好吧,呃.但问题不在于我“做错了”,而是我们被告知这样做是“错误的”.在Xamarin中没有其他方式可以在线找到我的短信.在线的每个示例似乎都基于这一个代码片段 – 给予或进行一些小的改动.我不知道现在该做什么.似乎没有一丝希望.
解决方法:
既然你说你将在Android Studio上使用Java,但没有给出答案,我会留下一个给你和其他可能正在寻找解决方案的人.
SmsReceiver.java：
package com.your.app;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.SmsMessage;
import android.util.Log;
import android.widget.Toast;
public class SmsReceiver extends BroadcastReceiver {
private static final String SMS_RECEIVED = "android.provider.Telephony.SMS_RECEIVED";
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(SMS_RECEIVED)) {
Bundle bundle = intent.getExtras();
if (bundle != null) {
// get sms objects
Object[] pdus = (Object[]) bundle.get("pdus");
if (pdus.length == 0) {
return;
}
// large message might be broken into many
SmsMessage[] messages = new SmsMessage[pdus.length];
StringBuilder sb = new StringBuilder();
for (int i = 0; i < pdus.length; i++) {
messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
sb.append(messages[i].getMessageBody());
}
String sender = messages[0].getOriginatingAddress();
Log.d("SNDR", sender);
String message = sb.toString();
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
// prevent any other broadcast receivers from receiving broadcast
abortBroadcast();
}
}
}
}
请务必将所需的权限和intent-filter添加到AndroidManifest.xml文件中.
AndroidManifest.xml中：
<uses-permission android:name="android.permission.RECEIVE_SMS" />
<application
android:allowBackup="true"
android:icon="@drawable/icon"
android:label="@string/app_name"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name="com.your.app.SmsReceiver" android:enabled="true">
<intent-filter android:priority="2147483647">
<action android:name="android.provider.Telephony.SMS_RECEIVED" />
</intent-filter>
</receiver>
</application>
标签：c,java,android,xamarin-android,xamarin-studio 来源： https://codeday.me/bug/20190703/1362087.html