Adding Quicklook to an existing NSTableView - macos

Question

I've been searching high and low for an example of an easy implementation of Quicklook to an existing NSTableView and while I've found example projects they're way beyond my skill set to disassemble and duct-tape into my project.
I can get the Quicklook window to appear when a button is pressed using
[[QLPreviewPanel sharedPreviewPanel] makeKeyAndOrderFront:nil];
But I haven't the slightest clue on how to set the data source so that the window is populated with the file.
Simply put, is there any stupid-simple tutorial on how to do this...?

Answer 1

Create a class that conforms to the QLPreviewItem protocol and implement:
- (NSURL *)previewItemURL {
// <Return File URL for file you want to preview>
}
Have your class that triggers the preview panel implement QLPreviewPanelDataSource, QLPreviewPanelDelegate and add the following to your implementation:
# pragma mark - QuartzPanel
- (IBAction)togglePreviewPanel:(id)previewPanel {
if ([QLPreviewPanel sharedPreviewPanelExists] && [[QLPreviewPanel sharedPreviewPanel] isVisible]) {
[[QLPreviewPanel sharedPreviewPanel] orderOut:nil];
} else {
[[QLPreviewPanel sharedPreviewPanel] makeKeyAndOrderFront:nil];
}
}
- (BOOL)acceptsFirstResponder {
return YES;
}
- (BOOL)acceptsPreviewPanelControl:(QLPreviewPanel *)panel {
return YES;
}
- (void)beginPreviewPanelControl:(QLPreviewPanel *)panel {
_previewPanel = panel; // create a property to hold a reference to your panel
panel.delegate = self;
panel.dataSource = self;
}
- (void)endPreviewPanelControl:(QLPreviewPanel *)panel {
_previewPanel = nil;
}
#pragma mark - QLPreviewPanelDataSource
- (NSInteger)numberOfPreviewItemsInPreviewPanel:(QLPreviewPanel *)panel {
return self.previewItems.count; // Items to preview of your custom subclass you created above
}
- (id <QLPreviewItem>)previewPanel:(QLPreviewPanel *)panel previewItemAtIndex:(NSInteger)index {
return (id<QLPreviewItem>)self.previewItems[index];
}
#pragma mark - QLPreviewPanelDelegate
- (BOOL)previewPanel:(QLPreviewPanel *)panel handleEvent:(NSEvent *)event {
// redirect all key down events to the table view
if ([event type] == NSKeyDown) {
NSString *key = [event charactersIgnoringModifiers];
if ([key isEqual:#" "]) {
[self togglePreviewPanel:self];
}
return YES;
}
return NO;
}