Reputation: 128428
I have tried to search on HashMap in Android, but getting problem:
Consider this example:
HashMap<String, String> meMap=new HashMap<String, String>();
meMap.put("Color1","Red");
meMap.put("Color2","Blue");
meMap.put("Color3","Green");
meMap.put("Color4","White");
now I want to iterate it and get the value of each color and want to display in "Toast". how do I display it?
Upvotes: 87
Views: 202507
Reputation: 1
Below code will generate unique random numbers list.
int size = 10; // Change according to your need
List<Integer> Lucky = new ArrayList<>();
while(Lucky.size()<size)
{
int r = new Random().nextInt(1000);
if(!Lucky.contains(r)) Lucky.add(r);
}
Upvotes: 0
Reputation: 704
Note: If you know Key, use this code
String value=meMap.get(key);
Upvotes: 1
Reputation: 1384
Iterator iterator = meMap.keySet().iterator();
while(iterator.hasNext() ){
//get key
String key=(String)iterator.next();
//toast value
Toast.makeText(getBaseContext(),""+(String)meMap.get(key),Toast.LENGTH_SHORT).show();
}
Upvotes: 1
Reputation: 180
for (Object key : meMap.keySet()) {
String value=(String)meMap.get(key);
Toast.makeText(ctx, "Key: "+key+" Value: "+value, Toast.LENGTH_LONG).show();
}
Upvotes: 4
Reputation: 3442
HashMap<String, String> meMap = new HashMap<String, String>();
meMap.put("Color1", "Red");
meMap.put("Color2", "Blue");
meMap.put("Color3", "Green");
meMap.put("Color4", "White");
Iterator myVeryOwnIterator = meMap.values().iterator();
while(myVeryOwnIterator.hasNext()) {
Toast.makeText(getBaseContext(), myVeryOwnIterator.next(), Toast.LENGTH_SHORT).show();
}
Upvotes: 7
Reputation: 162
This with no warnings!
HashMap<String, String> meMap=new HashMap<String, String>();
meMap.put("Color1","Red");
meMap.put("Color2","Blue");
meMap.put("Color3","Green");
meMap.put("Color4","White");
for (Object o : meMap.keySet()) {
Toast.makeText(getBaseContext(), meMap.get(o.toString()),
Toast.LENGTH_SHORT).show();
}
Upvotes: 8
Reputation: 73
this work for me:
HashMap<String, String> meMap=new HashMap<String, String>();
meMap.put("Color1","Red");
meMap.put("Color2","Blue");
meMap.put("Color3","Green");
meMap.put("Color4","White");
Iterator iterator = meMap.keySet().iterator();
while( iterator. hasNext() )
{
Toast.makeText(getBaseContext(), meMap.get(iterator.next().toString()),
Toast.LENGTH_SHORT).show();
}
Upvotes: 2
Reputation: 383676
Here's a simple example to demonstrate Map
usage:
Map<String, String> map = new HashMap<String, String>();
map.put("Color1","Red");
map.put("Color2","Blue");
map.put("Color3","Green");
map.put("Color4","White");
System.out.println(map);
// {Color4=White, Color3=Green, Color1=Red, Color2=Blue}
System.out.println(map.get("Color2")); // Blue
System.out.println(map.keySet());
// [Color4, Color3, Color1, Color2]
for (Map.Entry<String,String> entry : map.entrySet()) {
System.out.printf("%s -> %s%n", entry.getKey(), entry.getValue());
}
// Color4 -> White
// Color3 -> Green
// Color1 -> Red
// Color2 -> Blue
Note that the entries are iterated in arbitrary order. If you need a specific order, then you may consider e.g. LinkedHashMap
Map
interfaceOn iterating over entries:
Iterator
.On different Map
characteristics:
enum
You may want to consider using an enum
and EnumMap
instead of Map<String,String>
.
Upvotes: 93
Reputation: 207830
Iterator myVeryOwnIterator = meMap.keySet().iterator();
while(myVeryOwnIterator.hasNext()) {
String key=(String)myVeryOwnIterator.next();
String value=(String)meMap.get(key);
Toast.makeText(ctx, "Key: "+key+" Value: "+value, Toast.LENGTH_LONG).show();
}
Upvotes: 114
Reputation: 9595
HashMap<String, String> meMap=new HashMap<String, String>();
meMap.put("Color1","Red");
meMap.put("Color2","Blue");
meMap.put("Color3","Green");
meMap.put("Color4","White");
Iterator iterator = meMap.keySet().iterator();
while( iterator. hasNext() ){
Toast.makeText(getBaseContext(), meMap.get(iterator.next().toString()),
Toast.LENGTH_SHORT).show();
}
Upvotes: 2