-(NSString *)getPropertyType:(objc_property_t)property {
    NSString *propertyType = @"";
    unsigned int attrCount;
    objc_property_attribute_t *attrs = property_copyAttributeList(property, &attrCount);
    for (unsigned int i = 0; i < attrCount; i++) {
        if (attrs[i].name[0] == 'T') {
            if (attrs[i].value) {
                NSString *typeEncoding = [NSString stringWithUTF8String:attrs[i].value];
                
                if (typeEncoding.length > 0) {
                    NSScanner *scanner = [NSScanner scannerWithString:typeEncoding];
                    if (![scanner scanString:@"@\"" intoString:NULL]) continue;
                    
                    NSString *clsName = nil;
                    if ([scanner scanUpToCharactersFromSet: [NSCharacterSet characterSetWithCharactersInString:@"\"<"] intoString:&clsName]) {
                        if (clsName.length) propertyType = clsName;
                        break;
                    }
                }
            }
        }
    }
    return propertyType;
}

-(void)setSafeValue{
    NCBaseModelSafeType safePropertyTypeAll = [self safePropertyType];
    if (safePropertyTypeAll == NCBaseModelSafeTypeNone) {
        return;
    }
    NSMutableDictionary *safeTypeDic = [NSMutableDictionary dictionary];
    if (safePropertyTypeAll & NCBaseModelSafeTypeNSString) {
        [safeTypeDic setObject:@"" forKey:NSStringFromClass([NSString class])];
    }
    if (safePropertyTypeAll & NCBaseModelSafeTypeNSNumber) {
        [safeTypeDic setObject:@(0) forKey:NSStringFromClass([NSNumber class])];
    }
    if (safePropertyTypeAll & NCBaseModelSafeTypeNSArray) {
        [safeTypeDic setObject:@[] forKey:NSStringFromClass([NSArray class])];
    }
    
        unsigned int outCount, i;
        // 包含所有Property的数组
        objc_property_t *properties = class_copyPropertyList([self class], &outCount);
        // 遍历每个Property
        for (i = 0; i < outCount; i++) {
            // 取出对应Property
            objc_property_t property = properties[i];
            
            // 获取Property对应的变量名
            NSString *propertyName = [NSString stringWithUTF8String:property_getName(property)];
            // 获取Property的类型名
            NSString *propertyTypeName = [self getPropertyType:property];
            // 获取Property的值
            id propertyValue = [self valueForKey:propertyName];
            // 值为空，才设置默认值
            if (!propertyValue) {
                NSString *safeTypeKey =propertyTypeName;
                id safeTypeValue = safeTypeDic[safeTypeKey];
                if (safeTypeValue) {
                    [self setValue:safeTypeValue forKey:propertyName];
                }
            }
        }
        free(properties);
}

-(NCBaseModelSafeType)safePropertyType{
    return NCBaseModelSafeTypeNSString | NCBaseModelSafeTypeNSNumber | NCBaseModelSafeTypeNSArray;
}

- (void)cycleFromViewController: (UIViewController*) oldVC
               toViewController: (UIViewController*) newVC {
   // Prepare the two view controllers for the change.
   [oldVC willMoveToParentViewController:nil];
   [self addChildViewController:newVC];
 
   // Get the start frame of the new view controller and the end frame
   // for the old view controller. Both rectangles are offscreen.
   newVC.view.frame = [self newViewStartFrame];
   CGRect endFrame = [self oldViewEndFrame];
 
   // Queue up the transition animation.
   [self transitionFromViewController: oldVC toViewController: newVC
        duration: 0.25 options:0
        animations:^{
            // Animate the views to their final positions.
            newVC.view.frame = oldVC.view.frame;
            oldVC.view.frame = endFrame;
        }
        completion:^(BOOL finished) {
           // Remove the old view controller and send the final
           // notification to the new view controller.
           [oldVC removeFromParentViewController];
           [newVC didMoveToParentViewController:self];
        }];
}