如果想 USER 用特定次數便提示用家比 “錢” 買 完整版 ， 可以用呢個方法

本身 APPS 有個叫nsuserdefault 可以儲存資料， 例如APPS 登入資料， 用過幾次等

今次呢個 APPS 如果用家用過一次便會收 nsuserdefault 既 counter +1 , 除左儲 integer , 可以儲 string , 什至 array 都得

係你個 ACTION 個度加入。

int calCounter = [[NSUserDefaults standardUserDefaults] integerForKey:@"counter"];

calCounter +=1;

[[NSUserDefaults standardUserDefaults] setInteger:calCounter forKey:@"counter"];

[[NSUserDefaults standardUserDefaults] synchronize];

calCounter = [[NSUserDefaults standardUserDefaults] integerForKey:@"counter"];

NSLog(@"new counter %d",calCounter);

最後個兩句係比 CONSOLE 睇結果， 加唔加無乜所謂

係每次行 ACTION 前后

加上

calcounter%10 == 0 , 即係每 10 次問一問 ， 然后加入一個 FUNCTION

calCounter = [[NSUserDefaults standardUserDefaults] integerForKey:@"counter"];

if ( calCounter%10 == 0 && calCounter >1){

NSString *alertMessage = [NSString stringWithFormat:@"%d times calculation has been made",calCounter];

UIAlertView *alert = [[UIAlertView alloc]

initWithTitle:@"Go Get Full Version"

message:alertMessage

delegate:self cancelButtonTitle:@"Ignore"

otherButtonTitles:@"Buy Full Version",nil];

[alert show];

[alert release];

}