What is the ruling of Islamic law regarding the occurrence of divorce in the three mentioned cases?

The answer pertains to two issues:

First: If you are unsure whether what you swore by constitutes a divorce or an oath, the preponderant opinion is that an expiation for an oath (kaffarat yamin) is obligatory.

Second: If you said to your wife, "By Allah, I will divorce you if you take your father's phone," then if you intended to make the divorce effective upon the occurrence of the action, the divorce occurs when she takes the phone. But if you intended to swear an oath promising to divorce her in the future, then you have the choice between expiating for your oath or divorcing her. If you neither expiate nor divorce her, then divorce is not binding on you unless its occurrence becomes impossible due to the death of one of you, in which case expiation becomes binding. If the divorce occurs, you may take her back before her waiting period ('iddah) ends.