Bitcoin Forum

Bitcoin => Electrum => Topic started by: bomberb17 on January 17, 2021, 07:01:20 PM



Title: Load and broadcast signed transaction in Android electrum
Post by: bomberb17 on January 17, 2021, 07:01:20 PM
I have a signed transaction file .txn (signed on a PC) and want to load and broadcast it in Android electrum. I don't see such an option, is there any way? Maybe can broadcast it using another app or website?


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: jackg on January 17, 2021, 07:02:33 PM
Its at the bottom of one of the menus at the top (I think it's Tools but it could be wallet).


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: bomberb17 on January 17, 2021, 07:05:25 PM
Its at the bottom of one of the menus at the top (I think it's Tools but it could be wallet).

Can't find it. In the send tab, there are only 4 icons, then scan, then pay, no option to load txn file


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: bomberb17 on January 17, 2021, 07:22:53 PM
https://i.imgur.com/m7j424T.jpg ?


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: o_e_l_e_o on January 17, 2021, 07:33:10 PM
Open your Electrum wallet on desktop, load the signed transaction, and click the button at the bottom left which says "Export", and then click "Show as QR code".

On your mobile wallet, press the button on the page you have screenshotted which says "Scan". Scan the QR code from your computer. Broadcast the transaction.


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: jackg on January 17, 2021, 07:34:41 PM
Did you try to click copy and then the paste icon and save icon (the one that looks like a memory card)?

Otherwise, I'd go here: https://coinb.in/#broadcast and paste it in there. You could use the python idle app to open its contents and extract what you need (downloaded) if its not readable at the moment.


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: khaled0111 on January 17, 2021, 08:10:09 PM
Electrum on Android does not support this feature. You can't import a raw transaction saved as .txn file.

This leaves you with two options: Either save the transaction as a QR-Code and scan it using your mobile as o_e_l_e_o suggested or open the .txn file using any text editor on your mobile, copy its content then load it on Electrum by clicking the paste button. It worked for me.


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: HCP on January 17, 2021, 09:00:12 PM
You can't load .txn files into the android version of Electrum. That is only available on the desktop version.

EDIT: but, as per Khaled0111's tip above, you can load raw hex text into Android Electrum using the "paste" button on the "send" tab! ;)


If you have a signed transaction in .txn file, it should be just a plaintext file with the "Raw HEX" version of the transaction... any transaction broadcast tool/website should be able to send this out for you:

https://www.blockchain.com/btc/pushtx
https://live.blockcypher.com/btc/pushtx/
https://btc.com/tools/tx/publish
https://coinb.in/#broadcast

Note, I would advise that you use a "decode raw transaction" tool prior to broadcasting it, to double check it and make sure that all of the details (addresses and amounts etc) are correct:
https://www.blockchain.com/btc/decode-tx
https://live.blockcypher.com/btc/decodetx/
https://btc.com/tools/tx/decode
https://coinb.in/#verify


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: bomberb17 on January 17, 2021, 09:06:13 PM
I see. The QR code approach is not that useful (since you would use that PC to broadcast the transaction anyway).

So I guess the only option is to broadcast it using coinb.in


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: HCP on January 17, 2021, 09:10:38 PM
open the .txn file using any text editor on your mobile, copy its content then load it on Electrum by clicking the paste button. It worked for me.
That is a very nice (and somewhat undocumented) feature... thanks for sharing!

https://talkimg.com/images/2023/11/15/z3nam.png?1


So I guess the only option is to broadcast it using coinb.in
As above, you can follow khaled0111's tip and just "copy" the raw hex using a text editor on your Android device, and then in Electrum Android, on the "Send" tab... click the "paste" icon... it'll give you a preview of the signed transaction and the option to broadcast


Title: Re: Load and broadcast signed transaction in Android electrum
Post by: o_e_l_e_o on January 17, 2021, 09:17:23 PM
The QR code approach is not that useful (since you would use that PC to broadcast the transaction anyway).
The QR code approach is in fact the best option.

If the computer the signed transaction is currently stored on has an internet connection, then you can just use that computer to broadcast the transaction. If the computer does not have an internet connection, then chances are it is because you are using it as airgapped cold storage and want to move transactions back and forth from a live watch only wallet. The best way to do this is with QR codes, since it removes the attack vector of malware being transferred on removable media, or your private keys being leaked via removable media.