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Is there a way to access the 'hide my phone number' (caller ID) function with code in Android studio?

When you dial a phone number (on your Android phone), the person being called can see your phone number.
If you do not wish that, you can hide your phone number for outgoing calls from your phone by activating the corresponding feature.
Is there a way to access (toggle) this caller ID feature (hide/show) with code? I searched on the Internet but couldn't find anything.
And of course, if it is possible, what would be the code/method to do so?

Android Service to store Sim Card serial

i have a service to get Current Sim Serial and detect whether second sim card is inserted. So i would like to store the first sim card when the service run, Does anyone can tell me which way i can use to store integer value(sim serial).
When the second sim card inserted(after device reboot), i would like to compare the stored sim and current sim, if so detected then do something.
So basically i just want to write a sim card value to storage.

For store integer value(sim serial) You Should Use Android Preferences .
For More Refer these Links
http://developer.android.com/reference/android/preference/package-summary.html
http://viralpatel.net/blogs/android-preferences-activity-example/
http://www.javacodegeeks.com/2011/01/android-quick-preferences-tutorial.html

If you really are in for security id rather suggest using a PaaS like heroku and using your own web application to store that. Anyone can just erase the data from your application and have it think it is its first time running,

Is telephony manager values reliable and changeable (cdma)?

I want to know if I can rely on the telephony values like country, MCC, etc on Android for my app. Can I change them on the run using setprop? I tried changing using setprop it didn't seem to work. From my understanding telephony manager is a class/interface which represents Hardware configuration of GSM or CDMA. In case of GSM this could be sim and in case of CDMA it cud be a hardware. My questions are:
Who update these values in both the cases for the first time?
Are these values are saved by OS as read only?
What if a user travels to different country or zone will some of the values like country code and MCC values updated automatically?
Can I reset these values?
I have no intention of changing any of these values but want to understand its working! I would appreciate if someone can help me on this.

According to android documentation
Provides access to information about the telephony services on the
device. Applications can use the methods in this class to determine
telephony services and states, as well as to access some types of
subscriber information. Applications can also register a listener to
receive notification of telephony state changes.
TelephonyManager is used for reading phone information. Regarding your question about MCC & MNC codes: yes, they will change when phone will be in other country. You can subscribe to receive those events and determine that user now in different country.

#Bo
The way CDMA works is different from GSM. CDMA has always got one home base and many visitor base location. and you can always get to know about visitor Operator using TelephonyManager methods which is considered as unreliable for CDMA.

I decided to add it as answer as well...
I found a way to tackle this problem on CDMA phone.. if it is a CDMA phone , then the phone always has an ICC hardware comparable to SIM cards in GSM. All you gotta do is use the system properties associated with the hard ware . Programmatically you can use Java reflection to get this information . This is not changeable even system is rooted unlike GSM device. Class c=Class.forName("android.os.SystemProperties"); Method get = c.getMethod("get", String.class); String homeOperator = ((String) get.invoke(c, "ro.cdma.home.operator.numeric"));

How to determine the number of SIM cards on a device?

Sometimes we encounter some devices which have two or more SIM cards. So my question is:
How can I determine the number of SIM cards on the device?
Actually, I am developing a field test app and for example, if I have 2 SIM cards on the device, the user can choose between them to launch measurements.

There is currently no Android API for handling multiple SIM cards; any device support is entirely down to the handset manufacturer having modified the Android source. You could see if the particular manufacturer offers any kind of SDK or published API to help you, but it will be on a case by case basis.

All phones that support multiple sim card switching do so outside the android SDK so you'd have to contact their manufacturers for information about how they expose this functionality.

The question is very outdated and probably the answer was already found. But this may help someone else.
Beginning from Android API 22 you can do so via the SubscriptionManager like below:
val subManager = getSystemService(TELEPHONY_SUBSCRIPTION_SERVICE) as SubscriptionManager
val simCount = subManager.activeSubscriptionInfoCountMax //Total supported sim cards by device
val simAvailable = subManager.activeSubscriptionInfoCount // Currently active sim cards amount

Is it possible to make a sim and a tranciever send text messages to another sim ( with a tranciever )automatically?

Is it possible to make a sim and a transceiver send text messages to another sim ( with a transceiver )automatically?
(I'm not going to have a full fledged mobile ...I'm just going to use a microcontroller, transceiver and a sim)

I would start with a microprocessor like this which supports sending text messages already, http://en.wikipedia.org/wiki/Snapdragon_%28system_on_chip%29 , http://www.qualcomm.eu/uk/Snapdragon This is used in many popular smart phones.
Given these companies spend millions developing these solutions, even companies like Sony, Samsung and HTC use it (rather than develop their own) and you can buy the chips for a few dollars, it would make more sense to use something like this rather than develop your own IMHO.