修改以下代码public class MainActivity extends AppCompatActivity { private EditText number,content; private Button send; SmsManager smsManager; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //获取SmsManager smsManager = SmsManager.getDefault(); number = (EditText) findViewById(R.id.number); content = (EditText) findViewById(R.id.content); send = (Button) findViewById(R.id.send); send.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { PendingIntent pendingIntent = PendingIntent.getActivity(MainActivity.this,0,new Intent(),0); Log.i("Main","Pengding"+ pendingIntent); String phone = number.getText().toString(); String msg = content.getText().toString(); smsManager.sendTextMessage(phone,null,msg,pendingIntent,null); Log.i("Main","smsmanager"); Toast.makeText(MainActivity.this,"发送成功",Toast.LENGTH_SHORT); } }); } }

您需要在Toast.makeText()方法中添加.show()才能够显示Toast提示信息，修改后的代码如下：

public class MainActivity extends AppCompatActivity {
    private EditText number,content;
    private Button send;
    SmsManager smsManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //获取SmsManager
        smsManager = SmsManager.getDefault();

        number = (EditText) findViewById(R.id.number);
        content = (EditText) findViewById(R.id.content);
        send = (Button) findViewById(R.id.send);

        send.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                PendingIntent pendingIntent = PendingIntent.getActivity(MainActivity.this,0,new Intent(),0);
                Log.i("Main","Pengding"+ pendingIntent);
                String phone = number.getText().toString();
                String msg = content.getText().toString();
                smsManager.sendTextMessage(phone,null,msg,pendingIntent,null);
                Log.i("Main","smsmanager");
                Toast.makeText(MainActivity.this,"发送成功",Toast.LENGTH_SHORT).show();
            }
        });
    }
}

这样就可以在发送短信成功后弹出Toast提示“发送成功”了。