半手工打造一個Viewer (配合NIB)

//
//  main.m
//  
//
//  Created by unknown on 12/6/1.
//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import <UIKit/UIKit.h>

// 好用的列按鈕項目建立巨集
#define BARBUTTON(TITLE, SELECTOR)     [[UIBarButtonItem alloc] \
initWithTitle:TITLE style:UIBarButtonItemStylePlain target:self \
action:SELECTOR]

//Step 5.a 設計一個ViewController
@interface convertController:UIViewController
{
	
	UITextField *field1;
	UITextField *field2;
}
-(IBAction)doConvert:(id)sender;
@end

@implementation convertController
//Step 5.b 複寫loadView來佈置此ViewController的layerOut
-(void)loadView
{
	// 建立視圖
	self.view=[[[NSBundle mainBundle]loadNibNamed:@"View" owner:self options:NULL] lastObject];
	
	//映射到HelloWorldController的item
	field1=(UITextField *)[self.view viewWithTag:11];
	field2=(UITextField *)[self.view viewWithTag:12];
	
	[field1 setText:@"100"];
	
	UIBarButtonItem *convertButtonItem =[[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doConvert:)] autorelease];
	
	self.navigationItem.rightBarButtonItem=convertButtonItem;
	
	[self setTitle:@"Converter"];
    

}
-(IBAction)doConvert:(id)sender
{
	float invalue = [[field1 text] floatValue];
    float outvalue = (invalue - 32.0f) * 5.0f / 9.0f;
    [field2 setText:[NSString stringWithFormat:@"%3.2f", outvalue]];
    [field1 resignFirstResponder];
}
// 應用程式支援所有裝置擺設方向
- (BOOL) shouldAutorotateToInterfaceOrientation:
(UIInterfaceOrientation)toInterfaceOrientation
{
    return YES;
}
@end


//=====================
//Step 1.建立UIApplicationDelegaye class
@interface converDelegate :NSObject<UIApplicationDelegate>
{
//Step 2.加入window 指標	
	UIWindow *_window;
}

@end

@implementation converDelegate
//Step 3.複寫applicationDidFinishLaunching
-(void)applicationDidFinishLaunching:(UIApplication *)application
{
	//Step 4.構建window,並且保留在_window
	_window=[[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
	//Step 5.建構一個UINavigationController,並且初始化一個converController 物件當做RootViewController
	UINavigationController *nc=[[UINavigationController alloc]initWithRootViewController:[[convertController alloc]init]];
	//Step 6.把nc挂入到window的Root
	[_window setRootViewController:nc];
	//Step 7.show window 
	[_window makeKeyAndVisible];
}

@end


int main(int argc, char *argv[])
{
	@autoreleasepool {
	    return UIApplicationMain(argc, argv, nil, @"converDelegate");
	}
}