手工打造一Viewer

////  main.m//  ////  Created by unknown on 12/6/1.//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.//#import <UIKit/UIKit.h>// 好用的列按目建立巨集#define BARBUTTON(TITLE, SELECTOR)     [[UIBarButtonItem alloc] \initWithTitle:TITLE style:UIBarButtonItemStylePlain target:self \action:SELECTOR]//Step 5.a 一ViewController@interface convertController:UIViewController{UITextField *field1;UITextField *field2;}-(IBAction)doConvert:(id)sender;@end@implementation convertController//Step 5.b loadView置此ViewController的layerOut-(void)loadView{CGRect appFrame=[[UIScreen mainScreen]applicationFrame];//self.view=[[UIView alloc]initWithFrame:appFrame];field1 = [[UITextField alloc] initWithFrame:              CGRectMake(185.0, 16.0, 97.0, 31.0)];    field1.borderStyle = UITextBorderStyleRoundedRect;    field1.keyboardType = UIKeyboardTypeDecimalPad;    field1.clearButtonMode = UITextFieldViewModeAlways;        field2 = [[UITextField alloc] initWithFrame:              CGRectMake(185.0, 72.0, 97.0, 31.0)];    field2.borderStyle = UITextBorderStyleRoundedRect;    field2.enabled = NO;        UILabel *label1 = [[UILabel alloc] initWithFrame:                       CGRectMake(95.0, 19.0, 82.0, 21.0)];    label1.text = @"Fahrenheit";    label1.textAlignment = UITextAlignmentLeft;    label1.backgroundColor = [UIColor clearColor];        UILabel *label2 = [[UILabel alloc] initWithFrame:                       CGRectMake(121.0, 77.0, 56.0, 21.0)];    label2.text = @"Celsius";    label2.textAlignment = UITextAlignmentLeft;    label2.backgroundColor = [UIColor clearColor];        // 各元件加入容    [self.view addSubview:field1];    [self.view addSubview:field2];    [self.view addSubview:label1];    [self.view addSubview:label2];// 定文字，加入Convert按    self.title = @"Converter";    self.navigationItem.rightBarButtonItem = BARBUTTON(@"Convert", @selector(doConvert:));    }-(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];}@end//=====================//Step 1.建立UIApplicationDelegaye class@interface converDelegate :NSObject<UIApplicationDelegate>{//Step 2.加入window 指UIWindow *_window;}@end@implementation converDelegate//Step 3.applicationDidFinishLaunching-(void)applicationDidFinishLaunching:(UIApplication *)application{//Step 4.建window,且保留在_window_window=[[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];//Step 5.建一UINavigationController,且初始化一converController 物件做RootViewControllerUINavigationController *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];}@endint main(int argc, char *argv[]){@autoreleasepool {    return UIApplicationMain(argc, argv, nil, @"converDelegate");}}