I have a select that I get Json post with http, but I try to sets initially selected index but there is nothing in the list do not select anything. because the json is great.
public AppMainScreen() {
loadLists();
MySelect = new ObjectChoiceField( "Select: ", new Object[0], 3 );
VerticalFieldManager vfm = new VerticalFieldManager(Manager.VERTICAL_SCROLL);
vfm.add(MySelect);
add(vfm);
}
This statement appears wrong to me:
new ObjectChoiceField( "Select: ", new Object[0],3);
The second parameter to this constructor is supposed to be an array of objects whose .toString() method will be used to populate the choices. In this case, you have given it a 0 length array, i.e. no Objects. So there is nothing to choose. And then you have asked it to automatically select the 3rd item, and of course there is no 3rd item.
You should correct the code to actually supply an object array.
One option to make it easy is have your JSON load actually create a String array with one entry per selectable item. Then you use the index selected to identify the chosen item.
Related
I am using MYSQL through Sequelize to build a node.js application with typescript. I created a table and the table has a field which I made a JSON dataType and made it an array by default. I have been able to push items into the array. I would like to remove items from the array, how can I achieve this?
I tried using await category.update({array_Of_food:Sequelize.fn('array_remove',Sequelize.col('array_of_food'),JSON.stringify(category.dataValues.array_Of_food && category.dataValues.array_Of_food[index]))})
I got an error that array_remove does not exist.
I solved my problem this way since I couldn't find an inbuilt way of doing it. I know this is not the best method but at least it works. At the end, I wrote a longer code.
1.Get the string value of the item you want to remove.
const indexString = food.dataValues.food_Name as string;
2.Get the index number of that item inside the array you wish to delete it from:
const index = category.dataValues.array_Of_food?.indexOf(indexString) as number;
3.Create a variable for the the array out of the model colum that you are targeting.
const arrayValue = category.dataValues.array_Of_food
4.Remove that item from the array variable that you crceated:
arrayValue?.splice(index, 1);
5.Use the update method and pass the array variable you deleted the item from as the update: This will replace the initial array values with the new array values. Remember that the new array values contain all the values in the array column excluding the value you deleted.
await category.update({array_Of_food: arrayValue})
This worked!
I am trying to build a query to match two columns and I have tried the following:
obj= obj.filter(e => e.colOne.exactMatch(e.colTwo))
I am not be able to get this working, is there any way to filter by comparing the content of 2 columns?
The filter() method can't dynamically grab the value to filter based on each object, but can be used to filter on a static value.
You can filter a smaller object set (<100K rows) named myUnfilteredObjects of type ObjectType this way:
let myFilteredObjects = new Set<ObjectType>();
for (const unfilteredObj of myUnfilteredObjects) {
if (unfilteredObj.colOne === unfilteredObj.colTwo) {
myFilteredObjects.add(unfilteredObj);
}
}
Edit: updating with a solution for larger-scale object sets:
You can create a new boolean column in your object's underlying dataset that is true if colOne and colTwo match, and false otherwise. Filtering on this new column via the filter() method will then work as you expect.
It is not possible to compare two columns when writing Functions. A recommended strategy here would be to create a new column that captures your equality. For example in your pyspark pipeline, right before you generate the end objects that get indexed:
df.withColumn("colOneEqualsColTwo", F.when(
F.col("colOne") == F.col("colTwo"), True
).otherwise(False)
And then filter on that new column:
obj = obj.filter(e => e.colOneEqualsColTwo.exactMatch(true))
It is possible to preserve insertion order when parsing a JSON struct with a
Poco::JSON::Parser( new Poco::JSON::ParseHandler( true ) ): the non-default ParseHandler parameter preserveObjectOrder = true is handed over to the Poco::JSON::Objects so that they keep an private list of keys sorted in insertion order.
An object can then be serialized via Object::stringify() to look just like the source JSON string. Fine.
What, however, is the official way to step through a Poco::JSON::Object and access its internals in insertion order? Object::getNames() and begin()/end() use the alphabetical order of keys, not insertion order -- is there another way to access the values, or do I have to patch Poco?
As you already said:
Poco::JSON::ParseHandler goes into the Poco::JSON::Parser-constructor.
Poco::JSON::Parser::parse() creates a Poco::Dynamic::Var.
From that you'll extract a Poco::JSON::Object::Ptr.
The Poco::JSON:Object has the method "getNames". Beginning with this commit it seems to preserve the order, if it was requested via the ParseHandler. (Poco::JSON:Object::getNames 1.8.1, Poco::JSON:Object::getNames 1.9.0)
So now it should work as expected to use:
for(auto const & name : object->getNames()){
auto const & value = object->get(name); // or one of the other get-methods
// ... do things ...
}
How to get 'No User found' message from the below variable in Node.js
{"error":["No User found."]}
You can do it like this:
var data = {"error":["No User found."]};
alert(data.error[0]);
The outer object has a property "error". That property, then contains an array from which you want the first element in the array (index 0).
So, you get the error property with data.error. And, then you reach into the array and get the first element with data.error[0].
You need to iterate through this object with a for loop and grab the value based on the name of the property.
for(item in obj){
console.log(obj[item]);
}
You can use an if statement and the match method if you need to make sure that the property name is 'error'.
Here is my fiddle:
http://jsfiddle.net/nhmaggiej/eajqzxfr/
How can I iterate over a InputArray and load another input array with the same values except in lower case (I know that there is a string to lower function)?
Question: How to iterate over a String List with a LOOP structure?
InputArray: A, B, C
OutputArray should be: a, b, c
In case, you want to retain the inputArray as such and save the lowercase values in an outputArray, then follow steps in below image which is self explanatory:
In the loop Step, Input Array should be /inputArray and Output Array should be /outputArray.
Your InputArray field looks like a string field. It's not a string list.
You need to use pub.string:tokenize from the WmPublic package to split your strings into a string list and then loop through the string list.
A string field looks like this in the pipeline:
A string list looks like this in the pipeline:
See the subtle difference in the little icon at the left ?
I can see two cases out here.
If your input is a string
Convert the string to stringlist by pub.string:tokenize service.
Loop over the string list by providing the name of string list in input array property of loop.
within loop use pub.string:toLower service as transformer and map the output to an output string.
put the output string name in the output array property of Loop.
once you come out of the loop you will see two string lists, one with upper case and one with lower case.
If your input is a string list.
In this case follow steps 2 to 5 as mentioned above.