# IOS應用內購買
## 簡介
應用程序內購買是應用程序用于購買額外內容或升級功能。
### 實例步驟
1.在 iTunes 連接中請確保擁有一個唯一的 App ID（unique App ID ），當創建捆綁的ID（ bundle ID）應用程序更新時，代碼會以相應的配置文件簽名在Xcode上
2.創建新的應用程序和更新應用程序信息。你可以知道更多有關的，在蘋果的 添加新的應用程序 文檔中
3.在應用程序頁的管理應用程序( Manage In-App Purchase)中，為app內付費添加新產品
4.確保設置的應用程序為的銀行詳細。需要將其設置為在應用程序內購買（In-App purchase）。此外在 iTunes 中使用管理用戶（Manage Users）選項，創建一個測試用戶帳戶連接您的應用程序的頁。
5.下一步是與處理代碼和為我們在應用程序內購買創建有關的 UI。
6.創建一個單一的視圖應用程序，并在 iTunes 中指定的標識符連接輸入捆綁標識符
7.更新ViewController.xib ，如下所示
8.為三個標簽創建IBOutlets，且將按鈕分別命名為 productTitleLabel、 productDescriptionLabel、 productPriceLabel 和 purchaseButton
9.選擇項目文件，然后選擇目標，然后添加StoreKit.framework
10.更新ViewController.h ，如下所示
```
#import <UIKit/UIKit.h>
#import <StoreKit/StoreKit.h>
@interface ViewController : UIViewController<
SKProductsRequestDelegate,SKPaymentTransactionObserver>
{
SKProductsRequest *productsRequest;
NSArray *validProducts;
UIActivityIndicatorView *activityIndicatorView;
IBOutlet UILabel *productTitleLabel;
IBOutlet UILabel *productDescriptionLabel;
IBOutlet UILabel *productPriceLabel;
IBOutlet UIButton *purchaseButton;
}
- (void)fetchAvailableProducts;
- (BOOL)canMakePurchases;
- (void)purchaseMyProduct:(SKProduct*)product;
- (IBAction)purchase:(id)sender;
@end
```
11.更新ViewController.m ，如下所示
```
#import "ViewController.h"
#define kTutorialPointProductID
@"com.tutorialPoints.testApp.testProduct"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Adding activity indicator
activityIndicatorView = [[UIActivityIndicatorView alloc]
initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
activityIndicatorView.center = self.view.center;
[activityIndicatorView hidesWhenStopped];
[self.view addSubview:activityIndicatorView];
[activityIndicatorView startAnimating];
//Hide purchase button initially
purchaseButton.hidden = YES;
[self fetchAvailableProducts];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(void)fetchAvailableProducts{
NSSet *productIdentifiers = [NSSet
setWithObjects:kTutorialPointProductID,nil];
productsRequest = [[SKProductsRequest alloc]
initWithProductIdentifiers:productIdentifiers];
productsRequest.delegate = self;
[productsRequest start];
}
- (BOOL)canMakePurchases
{
return [SKPaymentQueue canMakePayments];
}
- (void)purchaseMyProduct:(SKProduct*)product{
if ([self canMakePurchases]) {
SKPayment *payment = [SKPayment paymentWithProduct:product];
[[SKPaymentQueue defaultQueue] addTransactionObserver:self];
[[SKPaymentQueue defaultQueue] addPayment:payment];
}
else{
UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:
@"Purchases are disabled in your device" message:nil delegate:
self cancelButtonTitle:@"Ok" otherButtonTitles: nil];
[alertView show];
}
}
-(IBAction)purchase:(id)sender{
[self purchaseMyProduct:[validProducts objectAtIndex:0]];
purchaseButton.enabled = NO;
}
#pragma mark StoreKit Delegate
-(void)paymentQueue:(SKPaymentQueue *)queue
updatedTransactions:(NSArray *)transactions {
for (SKPaymentTransaction *transaction in transactions) {
switch (transaction.transactionState) {
case SKPaymentTransactionStatePurchasing:
NSLog(@"Purchasing");
break;
case SKPaymentTransactionStatePurchased:
if ([transaction.payment.productIdentifier
isEqualToString:kTutorialPointProductID]) {
NSLog(@"Purchased ");
UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:
@"Purchase is completed succesfully" message:nil delegate:
self cancelButtonTitle:@"Ok" otherButtonTitles: nil];
[alertView show];
}
[[SKPaymentQueue defaultQueue] finishTransaction:transaction];
break;
case SKPaymentTransactionStateRestored:
NSLog(@"Restored ");
[[SKPaymentQueue defaultQueue] finishTransaction:transaction];
break;
case SKPaymentTransactionStateFailed:
NSLog(@"Purchase failed ");
break;
default:
break;
}
}
}
-(void)productsRequest:(SKProductsRequest *)request
didReceiveResponse:(SKProductsResponse *)response
{
SKProduct *validProduct = nil;
int count = [response.products count];
if (count>0) {
validProducts = response.products;
validProduct = [response.products objectAtIndex:0];
if ([validProduct.productIdentifier
isEqualToString:kTutorialPointProductID]) {
[productTitleLabel setText:[NSString stringWithFormat:
@"Product Title: %@",validProduct.localizedTitle]];
[productDescriptionLabel setText:[NSString stringWithFormat:
@"Product Desc: %@",validProduct.localizedDescription]];
[productPriceLabel setText:[NSString stringWithFormat:
@"Product Price: %@",validProduct.price]];
}
} else {
UIAlertView *tmp = [[UIAlertView alloc]
initWithTitle:@"Not Available"
message:@"No products to purchase"
delegate:self
cancelButtonTitle:nil
otherButtonTitles:@"Ok", nil];
[tmp show];
}
[activityIndicatorView stopAnimating];
purchaseButton.hidden = NO;
}
@end
```
**注意：** 需要修改你創建In-App Pur（應用內購買）的 kTutorialPointProductID 。通過修改fetchAvailableProducts產品標識符的 NSSet, 你可以添加多個產品。
### 輸出
運行該應用程序,輸出結果如下
確保已經中登錄。單擊購買選擇現有的Apple ID。輸入有效的測試帳戶的用戶名和密碼。幾秒鐘后，顯示下面的信息
一旦產品成功購買，將獲得以下信息。可以在顯示此信息的地方，更新應用功能相關的代碼
