How do you get a value for a key in java?

Open Source Development Extension Development
1

Hello everyone,
Can anyone tell me how to get a value for a key in java ?
I need it in my extension.
Any help is appreciated !
Thanks.

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2

Want to get values from appinventor from dictionaries to extension? do you just need to save something in the extension as a key-value?

You can use HashMap:

HashMap<String, Integer> saveData = new HashMap<String, Integer>();

Use:

saveData.put("apple",2);
saveData.remove("apple");
saveData.containsKey("apple");
saveData.get("apple");
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3

Any imports needed ?

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4

java.util.HashMap

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5

Thanks, trying it now itself and I'll tell you the result.

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6

Your method is working. Thank you !

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7

Oops, its showing 'cannot find symbol' - 'get'. How to solve it ?

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8

What and where does it show? PrintScren and show code.

9

[javac] /compiler/androidX/src/kppin/com/aquib/searchy/Searchy.java:76: error: cannot find symbol
[javac] res = text.get("answer");
[javac] ^
[javac] symbol: method get(String)
[javac] location: variable text of type String
[javac] 1 error

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10

It's not a problem with "get", just java basics ...

String res = text.get("answer");
11

Tried that too......
Not working.

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12

Make such code and compile. "Not working" is not enough.
If the value is of type Integer, it must be:
int res = text.get("...");

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13

[javac] /compiler/androidX/src/CsZdF/com/aquib/searchy/Searchy.java:75: error: cannot find symbol
[javac] String res = text.get("answer");
[javac] ^
[javac] symbol: method get(String)
[javac] location: variable text of type String
[javac] 1 error

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14

Show me the HashMap initialization line.

15

HashMap<text, text> saveData = new HashMap<text, text>();
:thinking:

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16

Is it consistent with what I wrote in post 2?

HashMap<String, String> text = new HashMap<String, String>();

Now the key and value must be of type String.

And now:

text.put("apple", "two");
text.remove("apple");
text.containsKey("apple");
String value = text.get("apple");
17

Its string only.

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18

You are given as on a tray, copy and paste - must work.

19

Just a min.... trying...

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20

Its showing cannot find symbol - 'HashMap'

[javac] /compiler/androidX/src/KyBYH/com/aquib/searchy/Searchy.java:75: error: cannot find symbol [javac] HashMap text = new HashMap(); [javac] ^ [javac] symbol: class text [javac] /compiler/androidX/src/KyBYH/com/aquib/searchy/Searchy.java:75: error: cannot find symbol [javac] HashMap text = new HashMap(); [javac] ^ [javac] symbol: class text [javac] /compiler/androidX/src/KyBYH/com/aquib/searchy/Searchy.java:75: error: cannot find symbol [javac] HashMap text = new HashMap(); [javac] ^ [javac] symbol: class text [javac] /compiler/androidX/src/KyBYH/com/aquib/searchy/Searchy.java:75: error: cannot find symbol [javac] HashMap text = new HashMap(); [javac] ^ [javac] symbol: class text [javac] 4 errors
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