如何通过重用单个视图控制器加载xib并处理内存警告

Question

我正在为iPhone制作一款由4款迷你游戏组成的游戏。每个迷你游戏都是一个独立的xib。每个游戏都有自己的菜单和游戏关卡。进入主菜单，选择要加载的游戏。

这就是我目前加载每个xib的方式。

MainGameViewController.h

@interface MainGameViewController : UIViewController {
    UIViewController *currentView;
    int currentViewId;
}
@property (nonatomic, retain) UIViewController *currentView;
- (void)displayView:(int)intNewView;
@end

MainGameViewController.m

@implementation MainGameViewController
@synthesize currentView;
- (void)viewDidLoad {
    [super viewDidLoad];
    currentView = [[LogoScreen alloc] init];
    [self.view addSubview:currentView.view];
}
- (void)displayView :(int)intNewView
{
    currentViewId = intNewView;
    currentView = nil;
    [currentView release];
    switch (intNewView) {
        case SCR_GAME1:
            currentView = [[Game1View alloc] init];
            break;
        case SCR_GAME1LEVEL:
            currentView = [[Game1LevelView alloc] init];
            break;
        case SCR_GAME2:
            currentView = [[Game2View alloc] init];
            break;
        case SCR_GAME2LEVEL:
            currentView = [[Game2LevelView alloc] init];
            break;
        case SCR_GAME3:
            currentView = [[Game3View alloc] init];
            break;
        case SCR_GAME3LEVEL:
            currentView = [[Game3LevelView alloc] init];
            break;
        case SCR_GAME4:
            currentView = [[Game4View alloc] init];
            break;
        case SCR_GAME4LEVEL:
            currentView = [[Game4LevelView alloc] init];
            break;       
        default:
            currentView = [[MainView alloc] init];
            break;
    }
    [self.view addSubview:currentView.view];
}
- (void)dealloc {
    [currentView release];
    currentView = nil;
    [super dealloc];
}
@end

这就是关卡的启动方式。Game1View.m

@implementation Game1View
-init {
    if (self == [super init]) {
        MainGameAppDelegate *appdelegate = [[UIApplication sharedApplication] delegate];
        isSoundOn = (appdelegate.gvar.soundstate == 1);
        gamestate = GAME_STATUS_START;
    }
    return self;
}
...
...
- (void)launchgame {
    MainGameAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
    appDelegate.gvar.currentId = objectid;
    [appDelegate displayView:SCR_GAME1LEVEL_GAME];
}
- (void)returnToMain {
    MainGameAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
    [appDelegate displayView:SCR_MAIN];
}
@end

MainGameAppDelegate.m

@implementation MainGameAppDelegate
@synthesize window;
@synthesize viewController;
- (void) displayView:(int)intNewView {
    [viewController displayView:intNewView];
}
@end

目前，当我不断在视图之间切换，然后应用程序崩溃时，我会收到内存警告。我的问题是，这是加载这些视图的正确方式吗？我已经发布了我在游戏寿命内分配的所有内容，现在我对占用内存的内容感到不知所措。任何帮助都将不胜感激。

Answer 1

您没有正确地发布游戏视图，因为您的代码在调用release之前实际上会将currentView设置为nil，这意味着您将泄露创建的每个游戏视图。

- (void)displayView :(int)intNewView
{
    currentViewId = intNewView;
    currentView = nil;
    [currentView release];
    switch (intNewView) {

你可能想这样做：

- (void)displayView :(int)intNewView
{
    currentViewId = intNewView;
    [currentView release];
    currentView = nil;
    switch (intNewView) {

此外，将视图控制器命名为"视图"会让人感到困惑。考虑给它们更多描述性的名称，比如xxxController。

编辑1:

您还需要确保旧游戏在发布之前已从视图层次结构中删除。在发布视图之前先调用[currentView.view removeFromSuperview]将其删除。