iPhone

开发平台：

MultiPlatform

PersistenceViewController.m：源码内容

							//
//  PersistenceAppDelegate.m
//  Persistence
//
//  Created by Jeff LaMarche on 7/29/08.
//  Copyright __MyCompanyName__ 2008. All rights reserved.
//
#import "PersistenceViewController.h"
#import "FourLines.h"
@implementation PersistenceViewController
@synthesize field1;
@synthesize field2;
@synthesize field3;
@synthesize field4;
- (NSString *)dataFilePath
{
	NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
	NSString *documentsDirectory = [paths objectAtIndex:0];
	return [documentsDirectory stringByAppendingPathComponent:kFilename];
	
}
- (void)applicationWillTerminate:(NSNotification *)notification
{
	//	NSMutableArray *array = [[NSMutableArray alloc] init];
	//	[array addObject:field1.text];
	//	[array addObject:field2.text];
	//	[array addObject:field3.text];
	//	[array addObject:field4.text];
	//	[array writeToFile:[self dataFilePath] atomically:YES];
	//	[array release];
	
	FourLines *fourLines = [[FourLines alloc] init];
	fourLines.field1 = field1.text;
	fourLines.field2 = field2.text;
	fourLines.field3 = field3.text;
	fourLines.field4 = field4.text;
	
	NSMutableData *data = [[NSMutableData alloc] init];
	NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data];
	[archiver encodeObject:fourLines forKey:kDataKey];
	[archiver finishEncoding];
	[data writeToFile:[self dataFilePath] atomically:YES];
	[fourLines release];
	[archiver release];
	[data release];
}
#pragma mark -
- (void)viewDidLoad {
	
	NSString *filePath = [self dataFilePath];
	if ([[NSFileManager defaultManager] fileExistsAtPath:filePath])
	{
		NSData *data = [[NSMutableData alloc] initWithContentsOfFile:[self dataFilePath]];
		NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data];
		FourLines *fourLines = [unarchiver decodeObjectForKey:kDataKey];
		[unarchiver finishDecoding];
		
		field1.text = fourLines.field1;
		field2.text = fourLines.field2;
		field3.text = fourLines.field3;
		field4.text = fourLines.field4;
		
		[unarchiver release];
		[data release];
	}
	
	UIApplication *app = [UIApplication sharedApplication];
	[[NSNotificationCenter defaultCenter] addObserver:self
											 selector:@selector(applicationWillTerminate:)
												 name:UIApplicationWillTerminateNotification 
											   object:app];
	[super viewDidLoad];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
	// Return YES for supported orientations
	return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
- (void)didReceiveMemoryWarning {
	[super didReceiveMemoryWarning]; // Releases the view if it doesn't have a superview
	// Release anything that's not essential, such as cached data
}
- (void)dealloc {
	[field1 release];
	[field2 release];
	[field3 release];
	[field4 release];
	[super dealloc];
}
@end

						