[Android Apps and Games] Parthib:
[IMG="TH-IMG"]https://drive.google.com/uc?export=download&id=0B7BTXFMgzL4rYWNaeUJLR3RiWG8[/IMG]

/*
* I'm not responsible for bricked devices, dead SD cards, thermonuclear war.
* Please do some research if you have any concerns about features included in the products you find here before flashing it!
* YOU are choosing to make these modifications, and if you point the finger at me for messing up your device, I will laugh at you.
* Your warranty will be void if you tamper with any part of your device / software.
* Same statement for XDA.
*/

About Dual Boot Patcher

Dual Boot Patcher will allow any number of ROMs to be installed at the same time. It works by patching the secondary ROM's installation scripts and boot image to load the ROM files from an alternate location (/system/multiboot, /cache/multiboot, and /data/multiboot). Because of the way this is implemented, no changes to the primary ROM are necessary. Huge thanks to [MENTION=4277844]chenxiaolong[/MENTION] for his wonderful app.

This app patches

Custom kernels for dual boot support

ROMs so that they can be installed as secondary

Google Apps packages for AOSP-based ROMs

SuperSU so that it can be used in the secondary ROM

How to use the patcher

Download the patcher apk and run it. Tap "Patch Zip File" from the navigation drawer and choose the file you want to patch.

Instructions for dual booting

The patcher offers several locations for installing ROMs

Primary: This is normally used for installing a zip to the primary ROM. It is not required, but is strongly recommended because it has code to prevent the zip from inadvertently affecting other ROMs.

Dual: Dual/Secondary is the first multiboot installation location. It installs to the

system partition

. This is a good spot for installing a second ROM because it doesn't take any space away from the internal storage.

Multi-slots: There are 3 multislots: multi-slot-1, multi-slot-2, multi-slot-3. These install to the

cache partition

. This is specifically for devices, like the Galaxy S4, that have a massive cache partition.

Data-slots: There can be an unlimited number of data slots. These install to the

data partition

and eat up space on the internal storage. This is useful for devices where the system partition is nearly full and the cache partition is tiny. These slots are named "data-slot-[id]", where "id" is something you provide in the app.

Extsd-slots: There can be an unlimited number of extsd slots. These install to the external SD card, which is useful as it keeps the ROMs off of the internal storage. Note that the ROM's data files

are still stored on the data partition

.

With that said, let's get to the "how to"!

First, boot into your primary ROM and install the Dual Boot Patcher app

Open the app and go to "Roms" in the navigation drawer. It will ask if you want to set the kernel. Make sure that you do.

Go to "Patch zip file" in the navigation drawer and patch the ROM or zip you want to install. You can select one of the installation locations described above.

There are two ways of flashing the patched zip file. You can either flash it normally from recovery or flash it using the in-app flashing feature. Both methods are explained below.

Flashing from recovery

To flash from recovery, just flash the patched zip file like you would for any other zip. Nice and simple.

In-app flashing

To use in-app flashing, go to "Roms" in the navigation drawer, tap the floating button on the bottom right, and add the zips you want to install. You can queue multiple zips and they will all be flashed in one go. Once you've added all the zips you want to flash, click the check mark in the action bar and they will be flashed right away.

NOTE:

A normal backup from recovery will backup every ROM. If you would like to back up ROMs individually, please see [MENTION=3145598]rlorange[/MENTION]'s awesome tool: http://xdaforums.com/showthread.php?t=2491299

If you want to dualboot a TouchWiz ROM, I highly recommend installing TouchWiz as the primary ROM. Otherwise, any mods will need to be patched before flashing.

How do I.. blah blah..?

Switch the ROM from custom recovery if something doesn't work properly?

You can flash the DualBootUtilities zip from recovery. It will provide a menu interface that allows switching to the various ROMs.

If you have TWRP, you can also switch manually by tapping Install -> Images (bottom right) -> Go to /sdcard/MultiBoot/[Your ROM]/ -> flash boot.img.

Wipe /cache, /data, /system, or dalvik-cache?

The easiest way is to do it from the app while booted in another ROM. Just go to "Roms" in the navigation drawer, tap the 3 dots options menu for the ROM you want to wipe, and tap "Wipe ROM".

Alternatively, flash the DualBootUtilities zip from recovery, which will also allow you to wipe a ROM.

NOTE: Don't use the recovery's built-in wiping abilities as that may delete non-primary

Update the primary ROM?

Patch the zip for primary and flash it. The "primary" installation target is designed so that other ROMs won't be affected when you want to flash something for the primary ROM.

Update a non-primary ROM?

Patch and flash the zip exactly like how you did it the first time.

Flash a mod or custom kernel for the primary ROM?

Patch it for primary before flashing. If the zip does not wipe /cache, it is also safe to flash it directly.

Flash a mod or custom kernel for a non-primary ROM?

Just patch and flash it :)

Downloads

Unofficial App/Apk : https://drive.google.com/open?id=0B7BTXFMgzL4rRXNBZUhaWl9PdWs

Unofficial DualBootUtilities : https://drive.google.com/open?id=0B7BTXFMgzL4rckFVZllCUV9DZ2s

Official Downloads : https://dbp.noobdev.io/downloads/

XDA:DevDB Information

Official Dual Boot Patcher for SM-J200H/DD

Contributors

Parthib, Lzzy12, samankh

Source Code: https://github.com/Parthib24/DualBootPatcher_downgrade

Version Information

Status: Testing

Main/Official Source code

DualBootPatcher: https://github.com/chenxiaolong/DualBootPatcher

Build instructions: https://github.com/chenxiaolong/DualBootPatcher/tree/master/docs

Created 2017-08-21

Last Updated 2017-08-21