I just need a user-friendly way to sweep bitcoins from a offline paper wallet onto the Blockchain, without having to expose your private key, whilst you are online. ....
The bitcoins in the paper wallet are already on the blockchain. What you are asking is about moving the private key from a paper wallet to some kind of wallet that can be used for transactions.
You can create a transaction off line. Hence it is possible to never expose a private key to an online wallet.
https://bitcointalk.org/index.php?topic=944915.0It only makes sense to me that a Paper wallet is meant to be created offline to increase the security and therefore it makes further sense that the Sweep/Import option should also be done offline first and then encrypted before you go online again.
The automated Encryption and Decryption of the Private key to import/sweep the wallet, would reduce the risk of the private key being compromised during the process to sweep/import these wallets, when you go online.
OfflineStep 1 - Scan QR code on Paper wallet and retrieve the Private key
Step 2 - Insert Private key into App
Step 3 - App Encrypt Private key
Step 4 - Insert Bitcoin Address where coins will be swept to
OnlineStep 5 - Go online
Step 6 - App still running, Click on "Sweep Paper Wallet"
Step 7 - Application automatically decrypt the Private key and sweep the coins from the paper wallet onto the Address specified in Step 4
Done