1.  Insert IBOutlet properties and action methods into the class AppDelegate :
1.  Insert IBOutlet properties and action methods into the class AppDelegate :

    @property (weak) IBOutlet NSWindow *window;
    @property (weak) IBOutlet NSScrollView *imageScrollView;
    @property (weak) IBOutlet NSScrollView *textScrollView;

    @property (weak) IBOutlet NSButton *scrollButton;

    - (IBAction)clickToScrollImageToBottom:(id)sender;
    - (IBAction)clickToScrollImageToTop:(id)sender;

    - (IBAction)clickToScrollTextLeftward:(id)sender;
    - (IBAction)clickToScrollTextRightward:(id)sender;

Implement these methods of class AppDelegate :
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification;
- (void)applicationWillTerminate:(NSNotification *)aNotification;
- (void)addScrollView;
- (void)addImageToScrollView
- (IBAction)clickToScrollImageToBottom:(id)sender;
- (IBAction)clickToScrollImageToTop:(id)sender;
- (IBAction)clickToScrollTextLeftward:(id)sender;
- (IBAction)clickToScrollTextRightward:(id)sender;

Frederick-Hsu/iOS_Objective_C_Development,Frederick-Hsu/iOS_Objective_C_Development