- (IBAction)openPDFFile:(id)sender {
NSOpenPanel *panel = [NSOpenPanel openPanel];
[panel setAllowsMultipleSelection:YES];
NSArray* fileArray = [NSArray arrayWithObjects:@"pdf", nil];
[panel setAllowedFileTypes:fileArray];
[panel beginSheetModalForWindow:self.window completionHandler:^(NSInteger result) {
if (result == NSOKButton)
{
[panel close];
NSWindow *keyWindow = [NSApplication sharedApplication].keyWindow;
if (self.window == keyWindow) {
[[self homeViewCtrl].collectionView addItemsWithURLs:[panel URLs]];
}
}
}];
}