为什么80%的码农都做不了架构师？>>> 
⼀、UITextField
UITextField（输⼊框）：是控制⽂本输⼊和显⽰的控件
UITextField核⼼功能主要包含3个⽅⾯： ⽂本显⽰ 输⼊控制 外观配置
1、⽂本显⽰
// textField.text = @"你好";
// textField.textAlignment = NSTextAlignmentCenter;
textField.textColor = [UIColor blueColor];
textField.placeholder = @"请输入我爱编程";
textField.font = [UIFont fontWithName:@"" size:20];
2、输⼊控制
textField.enabled = YES;
textField.clearsOnBeginEditing = NO;
textField.secureTextEntry = YES;
textField.keyboardType = UIKeyboardTypeDefault;
textField.returnKeyType = UIReturnKeyDefault;
//自定义键盘视图
UIView * inputView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 0, 180)];
inputView.backgroundColor = [UIColor blueColor];
textField.inputView = inputView;
[inputView release];
//自定义键盘辅助视图
UIView * inputAccessaryView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 0, 60)];
inputAccessaryView.backgroundColor = [UIColor yellowColor];
textField.inputAccessoryView = inputAccessaryView;
[inputAccessaryView release];
3、外观控制
textField.borderStyle = UITextBorderStyleRoundedRect;
textField.clearButtonMode = UITextFieldViewModeWhileEditing;
//设置文本框左视图
UIButton * button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0, 0, 40, 40);
[button setBackgroundImage:[UIImage imageNamed:@"face_monkey_2_24px_541648_easyicon.net.png"] forState:UIControlStateNormal];
textField.leftView = button;
textField.leftViewMode = UITextFieldViewModeAlways;
二、UIButton
1、UIButton的状态
normal（普通状态）
默认情况
对应的枚举常量：UIControlStateNormal
highlighted（高亮状态）
按钮被按下去的时候（手指还未松开）
对应的枚举常量：UIControlStateHighlighted
disabled（失效状态，不可用状态）
如果enabled属性为NO，就是处于disable状态，代表按钮不可以被点击
对应的枚举常量：UIControlStateDisabled
UIButton有很多种状态，它提供了一些便捷属性，可以直接获取当前状态下的文字、文字颜色、图片等
@property(nonatomic,readonly,retain) NSString *currentTitle;
@property(nonatomic,readonly,retain) UIColor *currentTitleColor;
@property(nonatomic,readonly,retain) UIImage *currentImage;
@property(nonatomic,readonly,retain) UIImage *currentBackgroundImage;
UIButton * button = [UIButton buttonWithType:UIButtonTypeSystem];
// button.backgroundColor = [UIColor blackColor];
button.frame = CGRectMake(30, 100, 50, 50);
// button.layer.cornerRadius = 20;
//设置前景图片
[button setImage:[UIImage imageNamed:@""] forState:UIControlStateNormal];
//设置背景图片
//设置普通状态下的背景图片
[button setBackgroundImage:[UIImage imageNamed:@"normal.png"] forState:UIControlStateNormal];
//设置高亮状态下的背景图片
[button setBackgroundImage:[UIImage imageNamed:@"hilighted.png"] forState:UIControlStateHighlighted];
//添加事件
[button addTarget:self action:@selector(clickButton:) forControlEvents:UIControlEventTouchUpInside];
//设置按钮title
[button setTitle:@"绿鸟" forState:UIControlStateNormal];
[button setTitle:@"蓝鸟" forState:UIControlStateHighlighted];
[button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
- (void)clickButton:(UIButton *)button
{
self.window.backgroundColor = [UIColor colorWithRed:random()%100/100.0 green:random()%100/100.0 blue:random()%100/100.0 alpha:1];
button.backgroundColor = [UIColor whiteColor];
}
三、AppDelegate
＊＊＊＊键盘收回＊＊＊＊
1、将AppDelegate作为UITextField的delegate
@interface AppDelegate : UIResponder <UIApplicationDelegate, UITextFieldDelegate>
2、AppDelegate.m⽂件实现textFieldShouldReturn:⽅法
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
[textField becomeFirstResponder];
NSLog(@"%s", __FUNCTION__);
}// became first responder
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
NSLog(@"%s", __FUNCTION__); // 输出方法名
[textField resignFirstResponder];
return YES;
}// called when 'return' key pressed. return NO to ignore.
3、添加代理
textField.delegate = self;
＊＊＊＊触摸键盘外空白区域隐藏键盘＊＊＊＊
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
if (![touch.view isKindOfClass: [UITextField class]] || ![touch.view isKindOfClass: [UITextView class]]) {
[self.window endEditing:YES];
}
[super touchesBegan:touches withEvent:event];
}
四、iOS程序启动流程
1、程序入口
int main(int argc, char * argv[]) {
@autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
}
UIApplicationMain剖析:
argc: argv[].count
argv[]: 存放的是所有的参数
principalClassName:如果是nil，UIApplicationMain()函数会给系统创建一个UIApplication这个类的一个对象，而且是唯一的，叫做应用程序对象
delegateClassName:UIApplicationMain()使用给定类创建代理并给应用程序设置代理
UIApplicationMain()这个函数，开启事件循环
2、UIApplicationDelegate
UIApplicationDelegate是⼀个OC的协议。⾥⾯声明了⼀堆⽅法，这些⽅ 法都与应⽤程序运⾏状态有关，它们由应⽤程序代理实现。UIApplication 对象负责调⽤。
iOS生命周期：
UIApplicationDelegate
程序启动：
application:didFinishLaunchingWithOptions:
applicationDidBecomeActive:
挂起：
applicationWillResignActive: （tag:按两下Home键只发送此消息）
applicationDidEnterBackground:
恢复：
applicationWillEnterForeground:
applicationDidBecomeActive: （tag:从此状态返回程序只发送此消息）
结束：
applicationWillResignActive:
applicationDidEnterBackground:
AppDelegate applicationWillTerminate:
输出函数名：
NSLog(@"%s", __FUNCTION__);