IOS開發（105）之處理不活動狀态

1 前言

應用程式遇到的最簡單的狀态是從活動過渡到不活動，然後再傳回到活動。今天我們進來用一個例子來看看其具體應用。

2 詳述

這張的内容比較簡單，就直接上代碼了

ZYViewController.m

//
//  ZYViewController.m
//  State Lab
//
//  Created by zhangyuc on 13-6-8.
//  Copyright (c) 2013年 zhangyuc. All rights reserved.
//

#import "ZYViewController.h"

@interface ZYViewController ()

@end

@implementation ZYViewController

@synthesize label;
@synthesize animate;

- (void)viewDidLoad
{
    [super viewDidLoad];
    //注冊通知
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationWillResignActive:) name:UIApplicationWillResignActiveNotification object:[UIApplication sharedApplication]];
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationDidBecomeActive:) name:UIApplicationDidBecomeActiveNotification object:[UIApplication sharedApplication]];
    
    CGRect bounds = self.view.bounds;
    CGRect labelFrame = CGRectMake(bounds.origin.x,CGRectGetMidY(bounds)-50, bounds.size.width,100);
    self.label = [[UILabel alloc] initWithFrame:labelFrame];
    label.font = [UIFont fontWithName:@"Helvetica" size:70];
    label.text = @"Archy!";
    label.textAlignment = UITextAlignmentCenter;
    label.backgroundColor = [UIColor clearColor];
    [self.view addSubview:label];
//    [self rotatelabelDown];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (void)dealloc {
    [label release];
    [super dealloc];
}

-(void)rotatelabelDown{
    //隐式動畫，Core Animation會将屬性從其目前值流暢的過渡到我們制定的值，完成後可以執行任何操作。
    [UIView animateWithDuration:0.5
                     animations:^{
                         //為标簽的transform設定特定的旋轉角度（以弧度為機關指定）。
                         label.transform = CGAffineTransformMakeRotation(M_PI);
                     }
                     //他們還設定一個完成程式塊來調用其他方法,使文本不停反複地顯示動畫
                     completion:^(BOOL finished){
                         [self rotateLabelUp];
                         
                     }];
}

-(void)rotateLabelUp{
    [UIView animateWithDuration:0.5
                     animations:^{
                         label.transform = CGAffineTransformMakeRotation(0);
                     }
                     completion:^(BOOL finished){
                         //添加判斷條件
                         if(animate)
                             [self rotatelabelDown];
                     }];
}

- (void)applicationWillResignActive:(UIApplication *)application
{
    NSLog(@"%@",NSStringFromSelector(_cmd));
    animate = NO;
}

- (void)applicationDidBecomeActive:(UIApplication *)application
{
    NSLog(@"%@",NSStringFromSelector(_cmd));
    animate = YES;
    [self rotatelabelDown];
}

@end
      

運作結果

控制台結果:

2013-06-08 13:20:24.265 State Lab[414:c07] application:didFinishLaunchingWithOptions:

2013-06-08 13:20:24.287 State Lab[414:c07] applicationDidBecomeActive:

2013-06-08 13:20:24.288 State Lab[414:c07] applicationDidBecomeActive:

按下Home按鈕控制台結果:

2013-06-08 13:21:57.394 State Lab[414:c07] applicationWillResignActive:

2013-06-08 13:21:57.395 State Lab[414:c07] applicationWillResignActive:

2013-06-08 13:21:57.396 State Lab[414:c07] applicationDidEnterBackground:

在次運作App結果：

控制台結果

2013-06-08 13:22:44.051 State Lab[414:c07] applicationWillEnterForeground:

2013-06-08 13:22:44.052 State Lab[414:c07] applicationDidBecomeActive:

2013-06-08 13:22:44.053 State Lab[414:c07] applicationDidBecomeActive:

3 結語