Delete Dmg File Mac 2017

DMG Files on Mac OS

May 05, 2017 AppDelete is an uninstaller that will remove not only applications but also widgets, preference panes, plugins, and screensavers along with their associated files. Without AppDelete these associated items will be left behind to take up space and potentially cause issues. Since DMG is a native Mac OS disk image format opening DMG file is as easy as double clicking on it in Finder. When you open DMG file this way, disk image stored inside DMG file will be mounted, and then opened in a separate Finder window. If DMG contains installation of an application, then installation window of the app will open.

In Mac OS file extension DMG is often referred as Apple Disk Image and is used to refer to files which store disk images. DMG files could be mounted as a volume in Finder. Currently DMG files on Mac OS are used to distribute software packages.

When software package in DMG file is opened it instructs Mac OS Finder to change its window in a way it is easy for user to copy application to the right folder. Finder window shows source application folder and the destination folder. All that user has to do is to drag and drop application folder to the destination folder. This will install an app.

Below are steps you need to take to install an application from DMG file:

Double click the DMG file. This will make its contents available in Finder.
Drag the application from the DMG window into Applications. This will initiate installation process.
Wait until the copy process is finished
Eject the DMG file (click Eject button on the Finder Sidebar)
Delete the DMG file

Similar file extensions

IMG file - Disk Image Format for Windows
ISO file - Image File Format

One of the aspects where Macs differ from Windows PCs the most is when it comes to installing applications. On Macs, you need mount a disk image and then unmount it and delete once the installation is finished, which can be a bit of a hassle, especially if you have to test many apps in a short amount of time.

Thinking of that, this time we’ll share a couple of neat little workflows that you can implement on your Mac using Automator. With any of them, every time you are done with an app installation on your Mac, you’ll be able to eject/unmount and delete the disk image in just a couple of clicks.

Let’s get started with how to set up these nice Automator workflows.

Delete DMG Files Automatically When You Eject Them

Mac Dmg Os

Step 1: Open Automator and choose to create a new document. From the available document types that show up on the dialog box, select Service.

Step 2: At the top of the right panel, make sure to choose from the dropdown menus the options ‘no input’ and ‘Finder’ respectively so that the end result is as the one pictured below.

Step 3: Next, on the left panel of Automator, search for the Run AppleScript action and drag it to the right panel. An AppleScript window will show up with some placeholder code in it.

Dmg File Pc

Delete that code and instead copy and paste the following one in the script box:

tell application 'Finder'
set selection_list to selection
if (count selection_list) < 1 then
display dialog ¬
'Please select a volume mounted from a disk image.' with title ¬
'No Selection Found' with icon stop ¬
buttons ['OK'] default button 1
return
end if
set my_selection to item 1 of selection_list
set my_kind to kind of my_selection
set my_name to name of my_selection
if my_kind is not 'Volume' then
display dialog ¬
'Please select a volume mounted from a disk image file.' with title ¬
'Selection is not a Disk Image' with icon stop ¬
buttons ['OK'] default button 1
return
end if
set volume_list to paragraphs of (do shell script 'hdiutil info | grep ^/dev/disk | grep -o '/Volumes/.*')
set source_list to paragraphs of (do shell script 'hdiutil info | grep ^image'-'alias | grep -o '/.*')
set match_found to false
repeat with v from 1 to (count volume_list)
if '/Volumes/' & my_name = item v of volume_list then
set match_found to true
exit repeat
end if
end repeat
if match_found is not equal to true then
display dialog ¬
'The selected volume does not appear to be a Disk Image.' with title ¬
'Could not find Disk Image' with icon stop ¬
buttons ['OK'] default button 1
return
else
set my_source to POSIX file (item v of source_list) as alias
move my_source to the trash
eject my_selection
--reveal my_source
end if
end tell

Step 4: Now save this Automator service and give it a name that is easy to remember.

Step 5: Once this is done, every time you have a disk image mounted, all you have to do is select it and on the Finder menu select Services and then Eject and Delete (or whatever you named the service you just created) and the disk image file will be both unmounted and deleted with one click.

Now, let’s take a look at another Automator workflow that achieves the same objective doing exactly the opposite.

Eject DMG Files Automatically When You Drag Them To the Trash

As you can see from the title, this Automator workflow allows you to achieve the same purpose, except that in reverse, so you can avoid this message every time you drag to the trash a mounted DMG file.

Here are the steps to create it.

Step 1: Create a new document in Automator and select Folder Action from the available document types.

Step 2: At the top of the right panel, select Other… from the dropdown menu. Then, on the dialog box that pops over, type ~/.Trash to work with that folder.

Step 3: Next, on the left panel, drag the Run Shell Script action to the right panel. On the two dropdown menus that show up, select /usr/bin/python and as arguments respectively.

Step 4: Replace the placeholder script in the script box with the following one: