MainActivity.java 文件源码

/**
 * Creates the activity, sets the view, and checks if Telephony is enabled.
 * Telephony enabled:
 *     Checks for phone permission.
 *     Sets the PhoneStateListener.
 * Telephony not enabled: Disables the call button and shows the Retry button.
 *
 * @param savedInstanceState Instance state
 */
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    // Create a telephony manager.
    mTelephonyManager = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
    // Check to see if Telephony is enabled.
    if (isTelephonyEnabled()) {
        Log.d(TAG, getString(R.string.telephony_enabled));
        // Check for phone permission.
        checkForPhonePermission();
        // Register the PhoneStateListener to monitor phone activity.
        mListener = new MyPhoneCallListener();
        mTelephonyManager.listen(mListener, PhoneStateListener.LISTEN_CALL_STATE);
    } else {
        Toast.makeText(this,
                R.string.telephony_not_enabled, Toast.LENGTH_LONG).show();
        Log.d(TAG, getString(R.string.telephony_not_enabled));
        // Disable the call button.
        disableCallButton();
    }
}