I'm quite new to progamming. So here's my function to select a random image in my drawable folder.
fun generateimage(index:Int)
{var images=arrayOf(R.drawable.img1,....)
main_imageView.setImageResource(images[index])
This works as an image is shown randomly every time I start the application. But I would like to be able to know which image was selected. Preferably from retrieving the image name to string.
Possible duplicate of
How to get drawable name from imageView
However, a better implementation would be to have the value in a list of int and put your R.drawable items inside it. That was you can access which element is being shown.
You can do something like this:
fun main() {
val arrayImages = arrayOf("image1", "image2", "image3", "image4", "image5")
// in your case actual images.
val randomIndex = (0..arrayImages.size).random()
val randomImage = arrayImages[randomIndex]
println(randomImage) // in your case: main_imageView.setImageResource(randomImage)
}
Note that you need to assign the variable of randomImage so you can access it later on. I don't know what type "R.drawable.img1" is, but the object you set inside this array has to store the name of the file, so you can retrieve it that way.
Related
I am coding a data class that is wanting to read a csv file to grab some information that is stored on the file. How ever, every way that I have tried to read the file will not work.
Here is what I have tried so far:
data class Bird(val birdNumIn: Int){
private var birdNum = birdNumIn
/**
* A function that searches the bird-data.csv file which is a list of birds to find the bird that was
* inputted into the class constructor and then add the values of the bird to the private variables.
*/
fun updateValues(){
var birdNumber = birdNum
var birdInfo: MutableList<String> = mutableListOf()
val minput = InputStreamReader(assets().open("bird-data.csv"), "UTF-8")
val reader = BufferedReader(minput)
}
How ever the assets().open() does not work. It returns an error of trying to open a file that does not exist, but the is in the assets folder, and the filename is spelt right.
I have tried many other methods on trying to read files, like using Java.io.File and using the path of the file.
If you would like to look at our whole project, please feel free to go to our github
What's the assets() function you're calling? This is just a bare data class, it has no connection to the Android environment it's running in, so unless you've injected an AssetManager instance (or a Context to pull it from) into your class, you can't access it.
You probably need to do this:
fun updateValues(context: Context){
val inputStream = context.assets.open("bird-data.csv")
val minput = InputStreamReader(inputStream, "UTF-8")
...
}
which requires your caller to have access to a Context.
Honestly from a quick look at your class, you might want to rework this. Instead of having a bunch of empty fields in your data class (which aren't part of the "data" by the way, only stuff in the constructor parameters is), and then having those updated later by the data class doing some IO, you might want to keep them as just basic stores of data, and create them when you read from your assets file.
So something like:
// all fixed values, initialised during construction
// Also you won't need to override toString now (unless you want to)
data class Bird(
val birdNum: Int
val nameOfBird: String
val birdFilePic: String
val birdFileSong: String
val alternativeName: String
val birdInfoFile: String
) { ... }
Then somewhere else
fun getBirbs(context: Context) {
// open CSV
// read the lines
val allBirds = lines.map {
// parse data for each bird, use it to construct a Bird object
}
}
or whatever you need to do, e.g. loading certain birds by ID.
That way your Bird class is just data and some functions/properties that work with it, it doesn't need a Context because it's not doing any I/O. Something else (that does have access to a Context) is responsible for loading your data and turning it into objects - deserialising it basically. And as soon as it's created, it's ready and initialised and immutable - you don't have to call update on it to get it actually initialised.
And if you ever wanted to do that a different way (e.g. loading a file from the internet) the data class wouldn't need to change, just the thing that does the loading. You could even have different loading classes! One that loads local data, one that fetches from the internet. The point is the separation of concerns, so it's possible to do this kind of thing because that functionality isn't baked into a class that's really about something else.
Up to you but just a thought! Especially if passing the context in like I suggested is a problem - that's a sign your design might need tweaking
In android studio I've created a map with hundreds of markers on it. I want to separate these into individual classes and put them in a separate package, so that there isn't one massive list of markers in my main code. Is there a way of doing this? I'm using Kotlin.
so what I think you are trying to say is.
There is an Activity let's say MainActivity and it has maps in it and has let's say some 200 markers on it.
and all are individually initialized and assigned and you want to club them all together so that you'll be able to use them just by searching for one.
if that's the case, what I would suggest is.
make a separate Data Class that stores Marker and other data related to it.
data class MarkerInfo(
//marker ID
val id:Int,
//marker Data
val markerData:Marker,
//other Data
var otherData:String
)
now coming to storing and accessing data.
class MainActivity(){
//at the top level, inside Activity
// This will create an empty list of Marker Info
var markerData = mutableListOf<MarkerInfo>()
//Now take any function, let's say x
private fun x(){
//Mark a Marker on Map and assign it to a variable.
val markerA : Marker = map.addMarker( MarkerOptions.position(somePosition))
//we assign a function with id and other relevant data
val x= markerData.size
//store data in list
markerData.add(MarkerInfo(x, markerA, "This is a very useful marker"))
}
}
//now to access that marker.
//let's say there is a function named y.
private fun y(){
//say we want to access the first marker
//there are two ways to do so.
//first method: you know some data which is already in there let's say we know id
for(i in markerData){
if(i.id == 1){
Log.d("TAG", i.toString())
}
}
//second method: directly
Log.d("TAG",markerData[0].toString())
}
I want to get all the attributes from my "Actual Item Inventry" (From Stock Items Form) so i have:
PXResultset<CSAnswers> res = PXSelectJoin<CSAnswers,
InnerJoin<InventoryItem,
On<CSAnswers.refNoteID, Equal<Current<InventoryItem.noteID>>>
>
>.Select(new PXGraph());
But, this returns me 0 rows.
Where is my error?
UPDATED:
My loop is like this:
foreach (PXResult<CSAnswers> record in res)
{
CSAnswers answers = (CSAnswers)record;
string refnoteid = answers.RefNoteID.ToString();
string value = answers.Value;
}
... but i can not go inside foreach.
Sorry for the English.
You should use an initialized graph rather than just "new PXGraph()" for the select. This can be as simple as "this" or "Base" depending on where this code is located. There are times that it is ok to initialize a new graph instance, but also times that it is not ok. Not knowing the context of your code sample, let's assume that "this" and "Base" were insufficient, and you need to initialize a new graph. If you need to work within another graph instance, this is how your code would look.
InventoryItemMaint graph = PXGraph<InventoryItemMaint>.CreateInstance<InventoryItemMaint>();
PXResultset<CSAnswers> res = PXSelectJoin<CSAnswers,
InnerJoin<InventoryItem, On<CSAnswers.refNoteID, Equal<Current<InventoryItem.noteID>>>>>
.Select(graph);
foreach (PXResult<CSAnswers> record in res)
{
CSAnswers answers = (CSAnswers)record;
string refnoteid = answers.RefNoteID.ToString();
string value = answers.Value;
}
However, since you should be initializing graph within a graph or graph extension, you should be able to use:
.Select(this) // To use the current graph containing this logic
or
.Select(Base) // To use the base graph that is being extended if in a graph extension
Since you are referring to:
Current<InventoryItem.noteID>
...but are using "new PXGraph()" then there is no "InventoryItem" to be in the current data cache of the generic base object PXGraph. Hence the need to reference a fully defined graph.
Another syntax for specifying exactly what value you want to pass in is to use a parameter like this:
var myNoteIdVariable = ...
InventoryItemMaint graph = PXGraph<InventoryItemMaint>.CreateInstance<InventoryItemMaint>();
PXResultset<CSAnswers> res = PXSelectJoin<CSAnswers,
InnerJoin<InventoryItem, On<CSAnswers.refNoteID, Equal<Required<InventoryItem.noteID>>>>>
.Select(graph, myNoteIdVariable);
foreach (PXResult<CSAnswers> record in res)
{
CSAnswers answers = (CSAnswers)record;
string refnoteid = answers.RefNoteID.ToString();
string value = answers.Value;
}
Notice the "Required" and the extra value in the Select() section. A quick and easy way to check if you have a value for your parameter is to use PXTrace to write to the Trace that you can check after refreshing the screen and performing whatever action would execute your code:
PXTrace.WriteInformation(myNoteIdVariable.ToString());
...to see if there is a value in myNoteIdVariable to retrieve a result set. Place that outside of the foreach block or you will only get a value in the trace when you actually get records... which is not happening in your case.
If you want to get deep into what SQL statements are being generated and executed, look for Request Profiler in the menus and enable SQL logging while you run a test. Then come back to check the results. (Remember to disable the SQL logging when done or you can generate a lot of unnecessary data.)
I created an ActivityNode (an Entry) and I can add custom fields with the
setFields(List<Field> newListField)
fonction.
BUT
I am unable to modify these fields. (In this case I try to modify the value of the field named LIBENTITE)
FieldList list = myEntry.getTextFields();
List<Field> updatedList = new ArrayList<Field>();
//I add each old field in the new list, but I modify the field LIBENTITE
for(Field myField : list){
if(myField.getName().equals("LIBENTITE")){
((TextField)myField).setTextSummary("New value");
}
updatedList.add(myField);
}
myEntry.setFields(updatedList);
activityService.updateActivityNode(myEntry);
This code should replace the old list of fields with the new one, but I can't see any change in the custom field LIBENTITE of myEntry in IBM connections.
So I tried to create a new list of fields, not modifying my field but adding a new one :
for(Field myField:list){
if(!myField.getName().equals("LIBENTITE")){
updatedList.add(myField);
}
}
Field newTextField = new TextField("New Value");
newTextField .setFieldName("LIBENTITE");
updatedList.add(newTextField );
And this code is just adding the new field in myEntry. What I see is that the other custom fields did not change and I have now two custom fields named LIBENTITE, one with the old value and the second with the new value, in myEntry.
So I though that maybe if I clear the old list of Fields, and then I add the new one, it would work.
I tried the two fonctions
myEntry.clearFieldsMap();
and
myEntry.remove("LIBENTITE");
but none of them seems to work, I still can't remove a custom field from myEntry using SBT.
Any suggestions ?
I have two suggestions, as I had (or have) similar problems:
If you want to update an existing text field in an activity node, you have to call node.setField(fld) to update the field in the node object.
Code snippet from my working application, where I'm updating a text field containing a (computed) start time:
ActivityNode node = activityService.getActivityNode(id);
node.setTitle(formatTitle()); // add/update start and end time in title
boolean startFound = false;
// ...
FieldList textfields =node.getTextFields();
Iterator<Field> iterFields = textfields.iterator();
while (iterFields.hasNext()) {
TextField fld = (TextField) iterFields.next();
if (fld.getName().equals(Constants.FIELDNAME_STARTTIME)) {
fld.setTextSummary(this.getStartTimeString()); // NOTE: .setFieldValue does *not* work
node.setField(fld); // write updated field back. This seems to be the only way updating fields works
startFound=true;
}
}
If there is no field with that name, I create a new one (that's the reason I'm using the startFound boolean variable).
I think that the node.setField(fld) should do the trick. If not, there might be a way to sidestep the problem:
You have access to the underlying DOM object which was parsed in. You can use this to tweak the DOM object, which finally will be written back to Connections.
I had to use this as there seems to be another nasty bug in the SBT SDK: If you read in a text field which has no value, and write it back, an error will be thrown. Looks like the DOM object misses some required nodes, so you have to create them yourself to avoid the error.
Some code to demonstrate this:
// ....
} else if (null == fld.getTextSummary()) { // a text field without any contents. Which is BAD!
// there is a bug in the SBT API: if we read a field which has no value
// and try to write the node back (even without touching the field) a NullPointerException
// will be thrown. It seems that there is no value node set for the field. We
// can't set a value with fld.setTextSummary(), the error will still be thrown.
// therefore we have to remove the field, and - optionally - we set a defined "empty" value
// to avoid the problem.
// node.remove(fld.getName()); // remove the field -- this does *not* work! At least not for empty fields
// so we have to do it the hard way: we delete the node of the field in the cached dom structure
String fieldName = fld.getName();
DeferredElementNSImpl fldData = (DeferredElementNSImpl) fld.getDataHandler().getData();
fldData.getParentNode().removeChild(fldData); // remove the field from the cached dom structure, therefore delete it
// and create it again, but with a substitute value
Field newEmptyField = new TextField (Constants.FIELD_TEXTFIELD_EMPTY_VALUE); // create a field with a placeholder value
newEmptyField.setFieldName(fieldName);
node.setField(newEmptyField);
}
Hope that helps.
Just so that post does not stay unanswered I write the answer that was in a comment of the initial question :
"currently, there is no solution to this issue, the TextFields are read-only map. we have the issue recorded on github.com/OpenNTF/SocialSDK/issues/1657"
I seem to be having a problem with assigning values to fields of a content item with a custom content part and the values not persisting.
I have to create the content item (OrchardServices.ContentManager.Create) first before calling the following code which modifies a field value:
var fields = contentItem.As<MyPart>().Fields;
var imageField = fields.FirstOrDefault(o => o.Name.Equals("Image"));
if (imageField != null)
{
((MediaLibraryPickerField)imageField).Ids = new int[] { imageId };
}
The above code works perfectly when against an item that already exists, but the imageId value is lost if this is done before creating it.
Please note, this is not exclusive to MediaLibraryPickerFields.
I noticed that other people have reported this aswell:
https://orchard.codeplex.com/workitem/18412
Is it simply the case that an item must be created prior to amending it's value field?
This would be a shame, as I'm assigning this fields as part of a large import process and would inhibit performance to create it and then modify the item only to update it again.
As the comments on this issue explain, you do need to call Create. I'm not sure I understand why you think that is an issue however.