Open a File from One App in Another Mac App with Proxy Icons

How often have you had a file open in one application on your Mac, only to need it opened in another OS X app instead? Fairly often, right? When confronted with that situation, most Mac users will do one of two things; go back to the Finder file system and re-open the file in the desired app, or open the other app and open the file directly from there. But there’s another way to re-open a file in one application from another, and it’s often faster and easier than the traditional methods.

This is going to use something called a Proxy icon, which is the little icon thumbnail that resides next to a saved files name in the titlebar of a file window. They appear in most Mac apps that support them, but if you’ve never heard the term proxy icon before, you’re probably not alone. Nonetheless, that little icon is interactive, and in this case we’re going to use it to relaunch a file into a new app.

Below is an example of what the proxy icon looks like for a demonstration saved file within TextEdit.

Note the file in question must be saved and reside in the file system somewhere, as unsaved files do not show a proxy icon in the titlebar. Additionally, not every single app in OS X supports them, though every default app on the Mac does.

To re-open this active file from one app to another, all you need to do is click and hold on the files proxy icon until it turns dark (this signifies it’s selected), then continue to hold and drag the files proxy icon into a new application icon.

That new app can be something stored in the Dock, which is what’s demonstrated in this screenshot example by opening a file from the Preview app into the Skitch app.

This also works to open files by dragging them into apps stored within the Finder toolbar or even Launchpad.

To drag a proxy icon into an app within Launchpad, simply click and hold the files proxy icon, then summon launchpad with a keystroke, or by holding the Option key as you drag over the Launchpad Dock icon. Then just drop the file icon onto the desired app as usual.

The titlebar proxy icons can also be used to create aliases in OS X, and by clicking into the actual filename you can even rename or move a file from the Mac titlebar too.