在我的应用程序中，我正在向移动设备发送端口短信。收到消息后，我需要在我的活动中执行一些任务并更新UI。
显示接收者的宣言
<receiver android:name="com.vfi.BinarySMSReceiver" >
<intent-filter android:priority="10" >
<action android:name="android.intent.action.DATA_SMS_RECEIVED" />
<data
android:host="*"
android:port="9512"
android:scheme="sms" />
</intent-filter>
</receiver>
接收器类
public class BinarySMSReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
SmsMessage[] msgs = null;
if (null != bundle) {
String info = "SMS from ";
String sender = "";
String msg = "";
Object[] pdus = (Object[]) bundle.get("pdus");
msgs = new SmsMessage[pdus.length];
byte[] data = null;
for (int i = 0; i < msgs.length; i++) {
msgs[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
sender += msgs[i].getOriginatingAddress();
info += msgs[i].getOriginatingAddress() + "\n";
data = msgs[i].getUserData();
for (int index = 0; index < data.length; ++index) {
info += Character.toString((char) data[index]);
msg += Character.toString((char) data[index]);
}
}
Log.e("SakjsdMS", "akjsdhkas" + msg);
Log.e("sender", "asdasdasdasdasdasd" + info);
((VerifyActivity)context).msgReceived(msg);
}
}
}
活动方法
public void msgReceived(String msgContent)
{
if(msgContent.equalsIgnoreCase(etMobile.getText().toString().trim())){
showToast("Number Verified");
}else{
showToast("Sorry wrong number. Input your number again.");
}
}
我得到的例外
java.lang.RuntimeException: Unable to start receiver com.vfi.BinarySMSReceiver: java.lang.ClassCastException: android.app.ReceiverRestrictedContext cannot be cast to com.vfi.VerifyActivity
at android.app.ActivityThread.handleReceiver(ActivityThread.java:2467)
at android.app.ActivityThread.access$1700(ActivityThread.java:145)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1319)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5127)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:825)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:641)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassCastException: android.app.ReceiverRestrictedContext cannot be cast to com.vfi.VerifyActivity
at com.vfi.BinarySMSReceiver.onReceive(BinarySMSReceiver.java:46)
at android.app.ActivityThread.handleReceiver(ActivityThread.java:2460)
在android.app.ActivityThread.access $ 1700（ActivityThread.java:145）
如何在接收器中获取活动上下文来调用我的方法？
我能够通过编程方式声明接收器来解决它：
在发送消息之前的活动中
private void sendSMS() {
BinarySMSReceiver smsReceiver = null;
smsReceiver = new BinarySMSReceiver();
smsReceiver.setActivityHandler(this);
IntentFilter portIntentFilter = new IntentFilter("android.intent.action.DATA_SMS_RECEIVED");
portIntentFilter.addDataAuthority("*", "9512");
portIntentFilter.addDataScheme("sms");
registerReceiver(smsReceiver, portIntentFilter);
String messageText = etMobile.getText().toString().trim();
short SMS_PORT = 9512;
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendDataMessage(etMobile.getText().toString().trim(), null, SMS_PORT, messageText.getBytes(), null, null);
}
在接收器类
public class BinarySMSReceiver extends BroadcastReceiver {
VerifyActivity vAct = null;
void setActivityHandler(VerifyActivity main) {
vAct = main;
}
@Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
SmsMessage[] msgs = null;
if (null != bundle) {
String info = "SMS from ";
String sender = "";
String msg = "";
Object[] pdus = (Object[]) bundle.get("pdus");
msgs = new SmsMessage[pdus.length];
byte[] data = null;
for (int i = 0; i < msgs.length; i++) {
msgs[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
sender += msgs[i].getOriginatingAddress();
info += msgs[i].getOriginatingAddress() + "\n";
data = msgs[i].getUserData();
for (int index = 0; index < data.length; ++index) {
info += Character.toString((char) data[index]);
msg += Character.toString((char) data[index]);
}
}
Log.e("message", "receiver " + msg);
Log.e("sender", "from " + info);
vAct.msgReceived(msg); //activity method
}
}
}
取消注册接收器
@Override
protected void onPause() {
super.onPause();
unregisterReceiver(smsReceiver);
}
你得到的错误是你错误地将android.app.ReceiverRestrictedContext投射到com.vfi.VerifyActivity。
如果您想实现您想要做的事情，只需通过提供一些额外信息开始您的活动。
public class BinarySMSReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
SmsMessage[] msgs = null;
if (null != bundle) {
String info = "SMS from ";
String sender = "";
String msg = "";
Object[] pdus = (Object[]) bundle.get("pdus");
msgs = new SmsMessage[pdus.length];
byte[] data = null;
for (int i = 0; i < msgs.length; i++) {
msgs[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
sender += msgs[i].getOriginatingAddress();
info += msgs[i].getOriginatingAddress() + "\n";
data = msgs[i].getUserData();
for (int index = 0; index < data.length; ++index) {
info += Character.toString((char) data[index]);
msg += Character.toString((char) data[index]);
}
}
Log.e("SakjsdMS", "akjsdhkas" + msg);
Log.e("sender", "asdasdasdasdasdasd" + info);
// HERE COMES THE CHANGE
Intent intent = new Intent(context, YourActivityToLaunch.class);
intent.putExtra("message_received", msg);
context.startActivity(intent);
}
}
}
在您的其他课程中，只需以这种方式检索您的信息：
Intent intent = getIntent();
String message = intent.getStringExtra("message_received");
而已。
希望这有帮助！
你的Context在BinarySMSReceiver传递的onReceive不是活动 - 它是Context in which the receiver is running。要启动Activity，您需要使用context.startActivity(Intent)并使用Intent将任何其他数据传递给Activity。
那((VerifyActivity)context).msgReceived(msg);那是你的错。你为什么假设这个背景是你的活动？
最好的方法（没有第三方库）来发送本地广播。
在另一个答案，我给出了如何使用LocalBroadcast Best practice to launch AsyncTask from custom view的一般概念
如果您使用第三方库，我建议您查看Otto的Square
默认情况下，您的BroadcastReceiver对任何活动都不了解。您必须为其提供上下文，例如在创建broadcastReceiver时在构造函数中。
private Activity activity;
public BroadcastReceiver(Activity activity) {
super();
this.activity = activity;
}
在on onceceive方法中，您现在可以以任何您喜欢的方式使用您的活动。