1 随機數的使用
頭檔案的引用
#import <time.h>
#import <mach/mach_time.h>
srandom()的使用
srandom((unsigned)(mach_absolute_time() & 0xFFFFFFFF));
直接使用 random() 來調用随機數
2 在UIImageView 中旋轉圖像
float rotateAngle = M_PI;
CGAffineTransform transform =CGAffineTransformMakeRotation(rotateAngle);
imageView.transform = transform;
以上代碼旋轉imageView, 角度為rotateAngle, 方向可以自己測試哦!
3 在Quartz中如何設定旋轉點
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"bg.png"]];
imageView.layer.anchorPoint = CGPointMake(0.5, 1.0);
這個是把旋轉點設定為底部中間。記住是在QuartzCore.framework中才得到支援。
4 建立.plist檔案并存儲
NSString *errorDesc; //用來存放錯誤資訊
NSMutableDictionary *rootObj = [NSMutableDictionary dictionaryWithCapacity:4]; //NSDictionary, NSData等檔案可以直接轉化為plist檔案
NSDictionary *innerDict;
NSString *name;
Player *player;
NSInteger saveIndex;
for(int i = 0; i < [playerArray count]; i++) {
player = nil;
player = [playerArray objectAtIndex:i];
if(player == nil)
break;
name = player.playerName;// This "Player1" denotes the player name could also be the computer name
innerDict = [self getAllNodeInfoToDictionary:player];
[rootObj setObject:innerDict forKey:name]; // This "Player1" denotes the person who start this game
}
player = nil;
NSData *plistData = [NSPropertyListSerialization dataFromPropertyList:(id)rootObj format:NSPropertyListXMLFormat_v1_0 errorDescription:&errorDesc];
紅色部分可以忽略,隻是給rootObj添加一點内容。這個plistData為建立好的plist檔案,用其writeToFile方法就可以寫成檔案。下面是代碼:
/*得到移動裝置上的檔案存放位置*/
NSString *documentsPath = [self getDocumentsDirectory];
NSString *savePath = [documentsPath stringByAppendingPathComponent:@"save.plist"];
/*存檔案*/
if (plistData) {
[plistData writeToFile:savePath atomically:YES];
}
else {
NSLog(errorDesc);
[errorDesc release];
}
- (NSString *)getDocumentsDirectory {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
return [paths objectAtIndex:0];
4 讀取plist檔案并轉化為NSDictionary
NSString *documentsPath = [self getDocumentsDirectory];
NSString *fullPath = [documentsPath stringByAppendingPathComponent:@"save.plist"];
NSMutableDictionary* plistDict = [[NSMutableDictionary alloc] initWithContentsOfFile:fullPath];
5 讀取一般性文檔檔案
NSString *tmp;
NSArray *lines; /*将檔案轉化為一行一行的*/
lines = [[NSString stringWithContentsOfFile:@"testFileReadLines.txt"]
componentsSeparatedByString:@"/n"];
NSEnumerator *nse = [lines objectEnumerator];
// 讀取<>裡的内容
while(tmp = [nse nextObject]) {
NSString *stringBetweenBrackets = nil;
NSScanner *scanner = [NSScanner scannerWithString:tmp];
[scanner scanUpToString:@"<" intoString:nil];
[scanner scanString:@"<" intoString:nil];
[scanner scanUpToString:@">" intoString:&stringBetweenBrackets];
NSLog([stringBetweenBrackets description]);
}
6 隐藏NavigationBar
[ self . navigationController setNavigationBarHidden: YES animated: YES ];
UIKeyboardWillShowNotification
UIKeyboardWillHideNotification
UIKeyboard...
iOS 5新增加了一些
UIKeyboardDidChangeFrameNotification(will)
一般情況下,前兩個事件已經可以完成你要做的事情。在你的事件處理方法中加上NSNotification參數可以為你獲得更多的東西:
- - (void)keyboardWillShow:(NSNotification *)notification
- {
- CGPoint beginCentre = [[[notification userInfo] valueForKey:UIKeyboardCenterBeginUserInfoKey] CGPointValue];
- CGPoint endCentre = [[[notification userInfo] valueForKey:UIKeyboardCenterEndUserInfoKey] CGPointValue];
- CGRect keyboardBounds = [[[notification userInfo] valueForKey:UIKeyboardBoundsUserInfoKey] CGRectValue];
- CGRect keyboardFrames = [[[notification userInfo] valueForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
- UIViewAnimationCurve animationCurve = [[[notification userInfo] valueForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
- NSTimeInterval animationDuration = [[[notification userInfo] valueForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
- }
如果你要在程式中使用鍵盤的高度和寬度,永遠不要嘗試去手動指定,動态擷取也很簡單而且一定準确,不會出現鍵盤擋住輸入框的問題。
你可以利用這些參數把動畫做的和鍵盤一緻。假設你要把一個控件放在Window上,并且想讓它的互動方式和鍵盤一樣,
如果隻是簡單的做個向下偏移動畫并不能很好的完成,因為你還要考慮從導航欄中Pop出來的時候,這個時候的鍵盤動畫是
在x軸上偏移的,你用UIKeyboardFrameEndUserInfoKey擷取的frame可以很準确的做到。