level3viewcontroller.m

一个用于下来菜单的xcode的手机程序。

/*

File: Level3ViewController.m
Abstract: The application's level 3 view controller.

Version: 1.1

Disclaimer: IMPORTANT:  This Apple software is supplied to you by Apple Inc.
("Apple") in consideration of your agreement to the following terms, and your
use, installation, modification or redistribution of this Apple software
constitutes acceptance of these terms.  If you do not agree with these terms,
please do not use, install, modify or redistribute this Apple software.

In consideration of your agreement to abide by the following terms, and subject
to these terms, Apple grants you a personal, non-exclusive license, under
Apple's copyrights in this original Apple software (the "Apple Software"), to
use, reproduce, modify and redistribute the Apple Software, with or without
modifications, in source and/or binary forms; provided that if you redistribute
the Apple Software in its entirety and without modifications, you must retain
this notice and the following text and disclaimers in all such redistributions
of the Apple Software.
Neither the name, trademarks, service marks or logos of Apple Inc. may be used
to endorse or promote products derived from the Apple Software without specific
prior written permission from Apple.  Except as expressly stated in this notice,
no other rights or licenses, express or implied, are granted by Apple herein,
including but not limited to any patent rights that may be infringed by your
derivative works or by other works in which the Apple Software may be
incorporated.

The Apple Software is provided by Apple on an "AS IS" basis.  APPLE MAKES NO
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
COMBINATION WITH YOUR PRODUCTS.

IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR
DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF
CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF
APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Copyright (C) 2008 Apple Inc. All Rights Reserved.

*/

#import "AppDelegate.h"
#import "Level3ViewController.h"
#import "LeafViewController.h"

@implementation Level3ViewController

NSString *kLevel3TitlePage = @"Level 3";

@synthesize listContent, leafViewController, myTableView;

- (void)dealloc
{
    [myTableView release];
	[listContent release];
	[super dealloc];
}

- (void)awakeFromNib
{	
	self.title = @"Level 3";
}


#pragma mark UIViewController delegates

- (void)viewWillAppear:(BOOL)animated
{
	[myTableView reloadData];	// populate our table's data
	
	NSIndexPath *tableSelection = [myTableView indexPathForSelectedRow];
	[myTableView deselectRowAtIndexPath:tableSelection animated:NO];
}


#pragma mark UITableView delegates

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
	return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
	return [listContent count];
}

- (UITableViewCellAccessoryType)tableView:(UITableView *)tableView accessoryTypeForRowWithIndexPath:(NSIndexPath *)indexPath
{
	return UITableViewCellAccessoryDisclosureIndicator;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
	// save off this level's selection to our AppDelegate
	AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
	[appDelegate.savedLocation replaceObjectAtIndex:2 withObject:[NSNumber numberWithInteger:indexPath.row]];
	
	leafViewController.title = [[listContent objectAtIndex:indexPath.row] objectForKey:kItemTitleKey];
	
	// move to the leaf level
	[[self navigationController] pushViewController:leafViewController animated:YES];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
	UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellIdentifier];
	if (cell == nil)
	{
		cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:kCellIdentifier] autorelease];
	}
	
	// get the view controller's info dictionary based on the indexPath's row
	NSDictionary* item = [listContent objectAtIndex:indexPath.row];
	cell.text = [item objectForKey:kItemTitleKey];
	return cell;
}

// User was last at level 3 or at a leaf page
//
// note: this is a part of a chain reaction down each level.
// so that each level restores itself and pushes further down until there's no further stored selections.
//
- (void)restoreLevel:(NSArray*)items withSelectionArray:(NSArray *)selectionArray
{
	// user was last at level 3 or at a leaf page
	//
	self.listContent = items;	// remember our content here at level 1 in case user navigates back to this level
	
	NSInteger itemIdx = [[selectionArray objectAtIndex:0] integerValue];
	if (itemIdx != -1)
	{
		leafViewController.title = [[listContent objectAtIndex:itemIdx] objectForKey:kItemTitleKey];
			
		// we have a selection, move one more level deep and restore its content
		// (not animated since the user should not see the restore process)
		[[self navigationController] pushViewController:leafViewController animated:NO];
	}
}

- (void)viewDidAppear:(BOOL)animated
{
	// we have moved to level 3, remove it's stored selection
	AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
	[appDelegate.savedLocation replaceObjectAtIndex:2 withObject:[NSNumber numberWithInteger:-1]];
}

@end