如何使用C ++ Builder发送电子邮件Android？

Question

I have seen many examples in Delphi and not one a C ++ builder. I tried to recreate the code in C ++, but it flies only exception. How to use the Intent to С++?

void __fastcall TForm1::Button1Click(TObject *Sender)
{
    callEmail("russia@gmail.com", "Application");
}
//---------------------------------------------------------------------------
void TForm1::callEmail(const String address, const String Subject){
  JIntent* intent;
  TJIntent* intentTwo;
  intent = intentTwo->Create();
  intent->setAction(intentTwo->JavaClass->ACTION_SEND);
  intent->setFlags(intentTwo->JavaClass->FLAG_ACTIVITY_NEW_TASK);
  intent->putExtra(intentTwo->JavaClass->EXTRA_EMAIL, StringToJString(address));
  intent->putExtra(intentTwo->JavaClass->EXTRA_SUBJECT, StringToJString(Subject));
  intent->setType(StringToJString('vnd.android.cursor.dir/email'));
  SharedActivity()->startActivity(intent);
}

I thnik, maybe I think maybe something needs to change in androidmanifest or user-permission?

Answer 1

Your code is crashing because you are not constructing the Intent object correctly.

Create() is a constructor in Delphi. intent := TJIntent.Create in Delphi would be intent = new TJIntent in C++.

Also, Embarcadero uses interfaces for its iOS/Android bridge frameworks, so you should use the provided DelphiInterface<T> typedefs, such as _di_JIntent instead of JIntent* directly.

Also, JavaClass (and OCClass in iOS) is a static class property. You do not need an object instance to access it, just the class type.

Also, C++ uses single-quotes for character literals and double-quotes for string literals, whereas Delphi uses single-quotes for both. 'vnd.android.cursor.dir/email' in C++ is not a string literal, it is a multi-byte character literal instead, which is not what you want here. Use double-quotes instead.

Also, EXTRA_EMAIL must be expressed as an array of strings.

Try something more like this:

void TForm1::callEmail(const String address, const String Subject)
{
    _di_JIntent intent;
    intent = new TJIntent; // or: intent = TJIntent::JavaClass->init();
    intent->setAction(TJIntent::JavaClass->ACTION_SEND);
    // or: intent = TJIntent::JavaClass->init(TJIntent::JavaClass->ACTION_SEND);
    intent->setFlags(TJIntent::JavaClass->FLAG_ACTIVITY_NEW_TASK);
    TJavaObjectArray__1<_di_JString> *Recipients = new TJavaObjectArray__1<_di_JString>(1);
    Recipients->Items[0] = StringToJString(address);
    intent->putExtra(TJIntent::JavaClass->EXTRA_EMAIL, Recipients);
    intent->putExtra(TJIntent::JavaClass->EXTRA_SUBJECT, StringToJString(Subject));
    intent->setType(StringToJString(L"vnd.android.cursor.dir/email"));
    SharedActivity()->startActivity(intent);
}

Now, that said, you really should not be using vnd.android.cursor.dir/email as the intent's MIME type. Use message/rfc822 instead, or even plain/text . But those do not limit the intent to just email clients, other apps might also support those types. To send an email using only a true email client, use ACTION_SENDTO with a mailto: URI instead. For 1 recipient, you can put the address directly in the URI and not use EXTRA_EMAIL at all. For 2+ recipients, use a mailto: URI with no address in it and use EXTRA_EMAIL for the addresses. This is mentioned in the Android documentation:

Common Intents | Email

For example:

void TForm1::callEmail(const String address, const String Subject)
{
    _di_JIntent intent;
    intent = new TJIntent; // or: intent = TJIntent::JavaClass->init();
    intent->setAction(TJIntent::JavaClass->ACTION_SENDTO);
    intent->setData(StrToJURI(L"mailto:" + address));
    // or: intent = TJIntent::JavaClass->init(TJIntent::JavaClass->ACTION_SENDTO, StrToJURI(L"mailto:" + address));
    intent->setFlags(TJIntent::JavaClass->FLAG_ACTIVITY_NEW_TASK);
    intent->putExtra(TJIntent::JavaClass->EXTRA_SUBJECT, StringToJString(Subject));
    intent->setType(StringToJString(L"message/rfc822"));
    SharedActivity()->startActivity(intent);
}