第一个iOS App RadioStation

Posted 2020-06-16

同样来自Mitch, Bennett, Lees的教材，本人编译环境为Xcode 7

新建ios Project, SingleView Application。

在Xcode环境中 - UI布局，添加UI对象，链接UI组件和UI对象。

 

UI布局：通过拖曳右下角的UI组件到Main.Storyboard中的空白Layout中

   

 

添加UI对象

本例中在ViewController的实例变量中添加了 IBOutlet类的各个UI组件的对象 - 对应三个动态Label，一个Slider

在类外面还定义了一个定义按钮动作的方法

 

定义好了之后右击对应的标签，将Reference Outlets一项拉出一条直线和对应的Label对象相连：

依次将要连接的动态标签，滑块，按钮都连接上。

 

之后再ViewController.m的viewDidLoad方法中添加动作，为按钮和滑块的动作添加实现：

//
//  ViewController.m
//  RadioStation
//
//  Created by 王 颖豪 on 2/25/16.
//  Copyright © 2016 UTT Wangsta. All rights reserved.
//

#import "ViewController.h"
#import "RadioStation.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    myStation = [[RadioStation alloc] initWithName:@"STAR 94" atFrequency:88.3];

}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
- (IBAction)sliderDidChange:(id)sender {
    [myStation setFrequency:setFrequency.value];
}

- (IBAction)buttonClick:(id)sender {
    [stationName setText:[myStation getName]];
    [stationFrequency setText:[NSString stringWithFormat:@"%.1f", [myStation getFrequency]]];
    if ([myStation getFrequency] >= [RadioStation minFMFrequency] &&
        [myStation getFrequency] <= [RadioStation maxFMFrequency]) {
        [stationBand setText:@"FM"];
    } else if( [myStation getFrequency] >= [RadioStation minAMFrequency] &&
               [myStation getFrequency] <= [RadioStation maxAMFrequency]){
        [stationBand setText:@"AM"];
    } else {
        [stationBand setText:@"Invalid Band!"];
    }
}

@end