java - 获取 HashMap<Integer, ArrayList<String>> 的所有子级

Question

我使用此代码添加到hashmap:

static HashMap<Integer, ArrayList<String>> arrayMap = new HashMap<Integer, ArrayList<String>>();

ArrayList<String> list = new ArrayList<String>();
list.add("t");
list.add("b");
arrayMap.put(12, list);

ArrayList<String> list = new ArrayList<String>();
list.add("y");
list.add("x");
arrayMap.put(18, list);

这段代码工作正常

但我无法在 foreach 中获取 arrayMap 的子元素

for(arrayMap .... ){
     return // 12:t,b   18:y,x
}

我的尝试:

for (int a = 0; a < arrayMap.size(); a++)
        {
            HashMap<String, Integer> tmpData = (HashMap<String, Integer>) arrayMap.get(a);
            Set<String> key = tmpData.keySet();
            Iterator it = key.iterator();
            while (it.hasNext()) {
                String hmKey = (String) it.next();
                Integer hmData = (Integer) tmpData.get(hmKey);

                System.out.println("Key: " + hmKey + " & Data: " + hmData);
                it.remove(); // avoids a ConcurrentModificationException
            }

        }

Answer 1

您需要迭代entrySet()

https://developer.android.com/reference/java/util/Map.html#entrySet()