open directory panel

ui/MainViewController.h

@@ -1,4 +1,4 @@
 #import <Cocoa/Cocoa.h>
 
-@interface MainViewController : NSViewController
+@interface MainViewController : NSViewController <NSOpenSavePanelDelegate>
 @end

ui/MainViewController.m

@@ -3,6 +3,7 @@
 
 @interface MainViewController ()
 
+@property (nonatomic, strong) NSOpenPanel *selectDirectoryPanel;
 @property (nonatomic, strong) NSButton *selectDirectoryButton;
 
 @end
@@ -18,17 +19,24 @@
     NSLog(@"[MainViewController] viewDidLoad");
     [super viewDidLoad];
 
+    // set window dimensions
     [self.view.widthAnchor constraintGreaterThanOrEqualToConstant:640.0].active = YES;
     [self.view.heightAnchor constraintGreaterThanOrEqualToConstant:480.0].active = YES;
 
+    // create open panel
+    self.selectDirectoryPanel = [NSOpenPanel openPanel];
+    [self.selectDirectoryPanel setCanChooseFiles:NO];
+    [self.selectDirectoryPanel setCanChooseDirectories:YES];
+    [self.selectDirectoryPanel setDelegate:self];
+
+    // create select directory button
     self.selectDirectoryButton = [NSButton buttonWithTitle:@"select directory"
-                                                    target:self
-                                                    action:@selector(fart:)];
+                                                    target:self.selectDirectoryPanel
+                                                    action:@selector(runModal)];
     [self.selectDirectoryButton setTranslatesAutoresizingMaskIntoConstraints:NO];
-
-
     [self.view addSubview:self.selectDirectoryButton];
 
+    // setup button constraints
     [self.selectDirectoryButton.rightAnchor
         constraintEqualToAnchor:self.view.rightAnchor
                        constant:-8.0].active = YES;
@@ -37,6 +45,11 @@
                        constant:8.0].active = YES;
 }
 
+- (void) panel:(id)sender didChangeToDirectoryURL:(NSURL *)url {
+    NSLog(@"[MainViewController] panel: %@ didChangeToDirectoryURL: %@", sender, url);
+    return [super viewWillAppear];
+}
+
 - (void) viewWillAppear {
     NSLog(@"[MainViewController] viewWillAppear");
     return [super viewWillAppear];
@@ -67,8 +80,4 @@
     return [super viewDidLayout];
 }
 
-- (void) fart {
-    NSLog(@"[MainViewController] fart!");
-}
-
 @end