Question

当我试图在应用程序处于for循环中时将NSMutableDictonary插入NSMutableArrey时，我遇到了一种非常奇怪的行为。

每个for-step构造NSMutableDict并添加到数组中。但它不起作用...当我在for循环后打印出数组时，数组中的每个NSMutableDictonary都是相同的 - 经过一些日志记录后，我看到每个for-step，数组中的所有dictionarys都被替换，并且添加了一个在最后...这是一个奇怪的行为，我不知道什么导致这... 如果我将currentID（见代码）添加到dictonary的数组中，最后看起来都很好...... 这是什么问题？

NSArray *relativeIAbnormality = [[NSArray alloc] init];
NSMutableDictionary *tempDict = [[NSMutableDictionary alloc] init];
NSMutableArray *tempArray = [[NSMutableArray alloc] init];

for (int q = 0; q < [measureData.list count]; q++) {
    [tempDict removeAllObjects];
    NSString *currentId = [[measureData.list objectAtIndex:q] valueForKey:@"id"];
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"id == %@", currentId];
    NSInteger count = [[lastMeasureData.list filteredArrayUsingPredicate:predicate] count];

    if(count > 0){

        // get the answer Value for the CURRENT measure
        float theValue = 0;
        theValue = [[[[measureData.list objectAtIndex:q] objectForKey:@"propertys"] valueForKey:@"answerValue"] floatValue];

        theValue = theValue/100;

        if(theValue > 10){
            theValue = 10;
        }else if (theValue < 0) {
            theValue = 0;
        }

        // get the answer Value for the LAST measure
        float theNewValue = 0;

        theNewValue = [[[[[lastMeasureData.list filteredArrayUsingPredicate:predicate] objectAtIndex:0] objectForKey:@"propertys"] valueForKey:@"answerValue"] floatValue];

        theNewValue = theNewValue/100;

        if(theNewValue > 10){
            theNewValue = 10;
        }else if (theNewValue < 0) {
            theNewValue = 0;
        }

        // gets the reltaive
        theValue = theValue - theNewValue;
        NSNumber *dif = [NSNumber numberWithFloat:theValue];

        [tempDict setObject:currentId forKey:@"id"];
        [tempDict setObject:dif forKey:@"dif"];

        //NSLog(@"tempDict: %@", tempDict);

        [tempArray addObject:tempDict];
        //NSLog(@"tempArray: %@", tempArray);
    }
}
//NSLog(@"full tempArray: %@", tempArray);

Answer 1

您继续使用相同的tempDict实例。将你的temp-dict的alloc-init对移到循环中。

NSArray *relativeIAbnormality = [[NSArray alloc] init];
NSMutableArray *tempArray = [[NSMutableArray alloc] init];
for (int q = 0; q < [measureData.list count]; q++) 
{
    NSMutableDictionary *tempDict = [[NSMutableDictionary alloc] init];
    ...
}

iOS：在for循环（双条目）中在NSArray中插入NSDictionary时出现奇怪的行为

1 个答案: