I have spent days to figure this out but no luck. Wish I could get answer from here.
I tried to load data into spinner from my content provider using the cursorLoader method.
The spinner seem had received the data but I found no data in the dropdown list, although several dropdown items (with no text) had been created.
I believe problem is not from my provider because if I use the same cursor to retrieve the data and put it into array, then bind the array to the spinner, then it shows all items correctly.
Below is my code,
package com.supreme2u.shopper;
import android.app.Activity;
import android.app.LoaderManager;
import android.content.CursorLoader;
import android.content.Loader;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.SimpleCursorAdapter;
import android.widget.Spinner;
import com.supreme2u.shopper.provider.ShopperProvider;
public class RecordActivity extends Activity implements LoaderManager.LoaderCallbacks<Cursor> {
private SimpleCursorAdapter sAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_record);
getLoaderManager().initLoader(0, null, this);
sAdapter = new SimpleCursorAdapter(
this,
android.R.layout.simple_spinner_item,
null,
new String[] {ShopperProvider.TAG_COLUMN_TAG},
new int[] {R.id.spinner1},
0);
sAdapter.setDropDownViewResource(android.R.layout.simple_spinner_item);
Spinner v = (Spinner) findViewById(R.id.spinner1);
v.setAdapter(sAdapter);
}
public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
CursorLoader cursorLoader = new CursorLoader(
this,
ShopperProvider.CONTENT_URI_TAGS,
ShopperProvider.TAG_COLUMNS,
null,
null,
null);
return cursorLoader;
}
public void onLoadFinished(Loader<Cursor> arg0, Cursor arg1) {
sAdapter.swapCursor(arg1);
}
public void onLoaderReset(Loader<Cursor> arg0) {
sAdapter.swapCursor(null);
}
}
And my layout xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Spinner
android:id="#+id/spinner1"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
And from my ShopperProvider class, extracted,
public static final Uri CONTENT_URI_TAGS = Uri.parse("content://com.supreme2u.shopper.provider/tableTag");
public static final String TAG_COLUMN_ID = "_id";
public static final String TAG_COLUMN_TAG = "tagName";
public static final String[] TAG_COLUMNS = {"_id","tagName"};
The problem lies in your construction of the SimpleCursorAdapter, specifically the second and fifth parameters (layout and to). From the docs:
layout: resource identifier of a layout file that defines the views for this list item. The layout file should include at least those named views defined in "to"
to: The views that should display column in the "from" parameter. These should all be TextViews. The first N views in this list are given the values of the first N columns in the from parameter. Can be null if the cursor is not available yet.
So you are correct to use android.R.layout.simple_spinner_item for layout. However, the views passed for to need to be TextViews and contained within android.R.layout.simple_spinner_item: i.e. android.R.id.text1 instead of R.id.spinner1.
In short, use this construction instead:
sAdapter = new SimpleCursorAdapter(
this,
android.R.layout.simple_spinner_item,
null,
new String[] {ShopperProvider.TAG_COLUMN_TAG},
new int[] {android.R.id.text1},
0);
Related
I wanted to connect a viewPager with an adapter (like this: viewPager.addOnPageChangeListener()), but the letters of the pageChangeListener just turn red like it wasn't a valid code...What am I doing wrong?? Heres a screenshot:
[1]: https://i.stack.imgur.com/IOYJY.png
Context: I'm currently working on a game with a few fragments where you can choose your game cards. I need the pageChangeListener to change the pictures of them cards. Maybe there could be another way to do this but i don't know how...
package com.suffv1
import android.os.Bundle
import androidx.appcompat.app.ActionBar
import androidx.appcompat.app.AppCompatActivity
import androidx.viewpager.widget.ViewPager
import com.example.suff_02.Adapter2
import com.example.suff_02.R
import com.example.suff_02.kartenmodell
import kotlinx.android.synthetic.main.activity_main.*
class MainActivity : AppCompatActivity(){
private lateinit var actionbar: ActionBar
private lateinit var liste: ArrayList<kartenmodell>
private lateinit var myAdapter: Adapter2
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
super.setContentView(R.layout.activity_main)
actionbar = this.supportActionBar!!
loadCards()
viewpager2.addOnPageChangeListener(object: ViewPager.OnPageChangeListener{
override fun onPageScrolled(
position: Int,
positionOffset: Float,
positionOffsetPixels: Int
) {
val title = liste[position].KartenImage
actionbar.title = title
}
})
}
private fun loadCards() {
liste = ArrayList()
liste.add(kartenmodell(R.drawable.bier_radler_klein_level_1))
liste.add(kartenmodell(R.drawable.bier_hopfentrunk_klein_level_1))
liste.add(kartenmodell(R.drawable.bier_butt_light_klein_level_1))
liste.add(kartenmodell(R.drawable.bier_becks_klein_level_1))
liste.add(kartenmodell(R.drawable.bier_tyskie_klein_level_1))
myAdapter = Adapter2(this, liste)
viewpager2.adapter = myAdapter
viewpager2.setPadding(100, 0, 100, 0)
}
}
Looks like you are using ViewPager2 not the original Viewpager and Viewpager2 does not have Page Change Listeners it instead has Page Change Callbacks
So you are using the wrong method to get notified when a pages is changed.
Instead do something like
var myPageChangeCallback = object : ViewPager2.OnPageChangeCallback() {
override fun onPageSelected(position: Int) {
Toast.makeText(this#MainActivity, "Selected position: ${position}",
Toast.LENGTH_SHORT).show()
}
}
viewpager.registerOnPageChangeCallback(myPageChangeCallback)
Though architecturally a lot of times it is bad form to use a OnPageChangeCallback as you are likely breaking the encapsulation idea of the Fragment and it can be better to use the lifecycle state change to Resumed of the Fragment to do things when a page(Fragment) is selected. e.g. put the code in the Fragments onResume method.
Though in this case of setting the actionbar title it is probably ok architecturally to use a OnPageChangeCallback
To create a AddOnPageChangeListener(), you do it as:
//See how, you have to use object to create an Object of the interface OnPageChangeListener.
//This is how you do for other listeners/interfaces/class as well when you've to implement its member functions instead of new in java.
viewPager.addOnPageChangeListener(object: ViewPager.OnPageChangeListener{
override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {
TODO("Not yet implemented")
}
override fun onPageSelected(position: Int) {
TODO("Not yet implemented")
}
override fun onPageScrollStateChanged(state: Int) {
TODO("Not yet implemented")
}
})
But, further in Kotlin, you can use Kotlin functions as
//This is for onPageSelected only.
viewPager.onPageChangeListener{ position: Int ->
//This position is the selected Page's position
}
I am getting following warning in Android Studio:
"Unconditional layout inflation from view adapter: Should use View Holder pattern (use recycled view passed into this method as the second parameter) for smoother scrolling." on inflater.inflate(R.layout.animal_ticket, null) line.
How do I fix the warning? I am not able to find solution for that problem.
Thanks!
override fun getView(p0: Int, p1: View?, p2: ViewGroup?): View {
val animal = listOfAnimals[p0]
val inflater = LayoutInflater.from(context)
var holder = ViewHolder()
val myView = inflater.inflate(R.layout.animal_ticket, null)
myView.tvName.text = animal.name!!
myView.tvDes.text = animal.description!!
myView.jvAnimalImage.setImageResource(animal.image!!)
return myView
}
If there was previously another View of the same view type (getItemViewType(position: Int) returned the same value) that scrolled off screen, the list view may pass in that instance as the second parameter to getView(). It will be faster to reuse that view than to inflate a new one.
You should also use the ViewHolder to cache things about the view, such as the relatively expensive findViewById(). You can attach it to and retrieve it from the view by tag.
override fun getView(position: Int, convertView: View?, parent: ViewGroup?) {
val animal = listOfAnimals[position]
val myView = convertView ?:
LayoutInflater.from(context).inflate(R.layout.animal_ticket, parent, false)
val holder = myView.tag as? ViewHolder ?: ViewHolder(myView)
myView.tag = holder
holder.tvName.text = animal.name!! // etc
}
class ViewHolder(view: View) {
val tvName: TextView = view.name // etc
}
For any RecyclerView, you need your own ViewHolder class that has all of the views listed inside animal_ticket.
Basically, it works like this:
1) Create ViewHolder that 'holds' all of the views of the item you want to display;
2) Bind the ViewHolder to the RecyclerView and assign values to the views inside;
Here is a example adapter I wrote :
class MyActivity : Activity() {
//users is the list we're going to use to get information for the views
val users = ArrayList<User>()
//...getting user information
//.. your activity stuff here
//Creating our adapter
/*
Note that to extend the RecyclerView.Adapter, you need to specify a
ViewHolder. The code becomes much easier to manage if you just put the
ViewHolder inside your adapter.
*/
inner class MyAdapter : RecyclerView.Adapter<MyAdapter.MyViewHolder>() {
//This is the view holder
inner class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
//Here you declare your views and get them from the itemView
//The itemView is one that is passed each time to the RecyclerView
//(the items inside your XML layout file)
internal val userImageView = itemView.findViewById(R.id.userImage)
internal val userFullName = itemView.findViewById(R.id.userName)
}
//This is where you return your own ViewHolder with your layout
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
//user_list_item.xml is below
val itemView = layoutInflater.inflate(R.layout.user_list_item, parent, false))
return MyViewHolder(itemView)
}
//In here is where you want to set your values for the views
override fun onBindViewHolder(holder: SentRequestViewHolder, position: Int) {
val currentUser = users[position]
holder.userImage.drawable = currentUser.drawable
holder.userFullName.text = currentUser.name
}
//You must override this method as well for the adapter to work properly
override fun getItemCount() = users.size
}
You have to override these methods when using a RecyclerView.Adapter
Here is the user_list_item.xml
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="100dp">
<ImageView
android:id="#+id/userImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView
android:id="#+id/userName"
android:layout_below="#id/userImage"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</RelativeLayout>
Im currently developing a application for watching who is responsible for different Patients, however i havent been able to solve how to fill a table with different object types.
Below is my code for my TableView controller. The TableView will end up with four different object typs, all will be retrieved from a database.
I want my table to hold Patient objects, User objects (responsible) and a RelationManager object.
Below is my code, if you need more of the code, please let me know :-).
package fird.presentation;
import fird.Patient;
import fird.RelationManager;
import fird.User;
import fird.data.DAOFactory;
import fird.data.DataDAO;
import java.net.URL;
import java.util.Arrays;
import java.util.List;
import java.util.ResourceBundle;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.TextField;
import javafx.scene.control.cell.PropertyValueFactory;
/**
* FXML Controller class
*
* #author SimonKragh
*/
public class KMAMainFrameOverviewController implements Initializable {
#FXML
private TextField txtCPRKMAMainFrame;
#FXML
private TableColumn<Patient, String> TableColumnCPR;
#FXML
private TableColumn<Patient, String> TableColumnFirstname;
#FXML
private TableColumn<Patient, String> TableColumnSurname;
#FXML
private TableColumn<User, String> TableColumnResponsible;
#FXML
private TableColumn<RelationManager, String> TableColumnLastEdited;
#FXML
private TableView<RelationManager> tblPatients;
#FXML
private Button btnShowHistory;
#FXML
private TableColumn<?, ?> TableColumnDepartment;
/**
* Initializes the controller clas #FXML private Button btnShowHistory;
*
* #FXML private TableColumn<?, ?> TableColumnDepartment; s.
*/
#Override
public void initialize(URL url, ResourceBundle rb) {
// Start of logic for the KMAMainFrameOverviewController
DataDAO dao = DAOFactory.getDataDao();
TableColumnCPR.setCellValueFactory(new PropertyValueFactory<Patient, String>("CPR"));
TableColumnFirstname.setCellValueFactory(new PropertyValueFactory<Patient, String>("Firstname"));
TableColumnSurname.setCellValueFactory(new PropertyValueFactory<Patient, String>("Surname"));
TableColumnResponsible.setCellValueFactory(new PropertyValueFactory<User, String>("Responsible"));
TableColumnLastEdited.setCellValueFactory(new PropertyValueFactory<RelationManager, String>("Last Edited"));
ObservableList<RelationManager> relationData = FXCollections.observableArrayList(dao.getAllActiveRelations());
tblPatients.setItems(relationData);
tblPatients.getColumns().addAll(TableColumnCPR, TableColumnFirstname, TableColumnSurname, TableColumnResponsible, TableColumnLastEdited);
System.out.println(tblPatients.getItems().toString());
}
}
relationData is a RelationManager object returned. This object contains a User object, a Patient object and a Responsible object.
Best,
Simon.
The exact details of how you do this depend on your requirements: for example, for a given RelationManager object, do the User, Patient, or Responsible objects associated with it ever change? Do you need the table to be editable?
But the basic idea is that each row in the table represents some RelationManager, so the table type is TableView<RelationManager>. Each column displays a value of some type (call it S), so each column is of type TableColumn<RelationManager, S>, where S might vary from one column to the next.
The cell value factory is an object that specifies how to get from the RelationManager object to an observable value of type S. The exact way you do this depends on how your model classes are set up.
If the individual objects associated with a given RelationManager never change (e.g. the Patient for a given RelationManager is always the same), then it's pretty straightforward. Assuming you have the usual setup for Patient:
public class Patient {
private StringProperty firstName = new SimpleStringProperty(...);
public StringProperty firstNameProperty() {
return firstName ;
}
public String getFirstName() {
return firstName.get();
}
public void setFirstName(String firstName) {
this.firstName.set(firstName);
}
// etc etc
}
then you can just do
TableColumn<RelationManager, String> firstNameColumn = new TableColumn<>("First Name");
firstNameColumn.setCellValueFactory(new Callback<CellDataFeatures<RelationManager,String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(CellDataFeatures<RelationManager, String> data) {
return data.getValue() // the RelationManager
.getPatient().firstNameProperty();
}
});
If you are not using JavaFX properties, you can use the same fallback that the PropertyValueFactory uses, i.e.:
TableColumn<RelationManager, String> firstNameColumn = new TableColumn<>("First Name");
firstNameColumn.setCellValueFactory(new Callback<CellDataFeatures<RelationManager,String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(CellDataFeatures<RelationManager, String> data) {
return new ReadOnlyStringWrapper(data.getValue().getPatient().getFirstName());
}
});
but note that this won't update if you change the name of the patient externally to the table.
However, none of this will work if the patient object associated with the relation manager is changed (the cell will still be observing the wrong firstNameProperty()). In that case you need an observable value that changes when either the "intermediate" patient property or the firstNameProperty change. JavaFX has a Bindings API with some select(...) methods that can do this: unfortunately in JavaFX 8 they spew out enormous amounts of warnings to the console if any of the objects along the way are null, which they will be in a TableView context. In this case I would recommend looking at the EasyBind framework, which will allow you to do something like
firstNameColumn.setCellValueFactory( data ->
EasyBind.select(data.getValue().patientProperty())
.selectObject(Patient::firstNameProperty));
(EasyBind requires JavaFX 8, so you if you get to use it, you also get to use lambda expressions and method references :).)
In either case, if you want the table to be editable, there's a little extra work to do for the editable cells in terms of wiring editing commits back to the appropriate call to set a property.
I'm working on a JavaFX application which has a layout generated from an external data structure, composed of
displaying components that know their own aspect ratios (height as a dependent of width)
2 types of structural components that
display all children with an equal width across their page, each child up as much vertical space as needed
display all children down the page using the full width and taking as much vertical space as needed
But I'm finding things aren't displaying as I expect. I've made a simplified case that demonstrates the problem.
The code is below, and the problem is that v3 doesn't get displayed, and I can't for the life of me work out why. I guess there's some facet of VBoxes and HBoxes that I haven't understood.
I'd really appreciate any help or ideas. Thanks in advance!
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Priority;
import javafx.scene.layout.Region;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
import java.util.Random;
public class Test extends Application {
static Random rand = new Random();
public static void main(String args[]) {
Application.launch("something");
}
#Override
public void start(Stage mainStage) throws Exception {
testVBoxes(mainStage);
}
private void testVBoxes(Stage mainStage) {
VBox root = new VBox();
Scene one = new Scene(root, 800, 600, Color.WHITE);
FixedAspectRatioH h1 = new FixedAspectRatioH();
FixedAspectRatioH h2 = new FixedAspectRatioH();
FixedAspectRatioH h3 = new FixedAspectRatioH();
FixedAspectRatioV v1 = new FixedAspectRatioV();
FixedAspectRatioV v2 = new FixedAspectRatioV();
FixedAspectRatioV v3 = new FixedAspectRatioV();
h1.prefWidthProperty().bind(root.widthProperty());
h2.add(v2);
v1.add(h3);
v1.add(h2);
h1.add(v1);
h1.add(v3);
root.getChildren().add(h1);
mainStage.setScene(one);
mainStage.show();
}
private class FixedAspectRatioV extends VBox {
public FixedAspectRatioV() {
Rectangle r = new Rectangle();
r.setFill(Color.rgb(rand.nextInt(256), rand.nextInt(256), rand.nextInt(256)));
r.widthProperty().bind(widthProperty());
r.heightProperty().bind(r.widthProperty().divide(3));
getChildren().add(r);
}
public void add(Region n) {
n.prefWidthProperty().bind(widthProperty());
getChildren().add(n);
}
}
private class FixedAspectRatioH extends HBox {
public FixedAspectRatioH() {
Rectangle r = new Rectangle();
r.setFill(Color.rgb(rand.nextInt(256), rand.nextInt(256), rand.nextInt(256)));
r.widthProperty().bind(widthProperty().divide(4));
r.heightProperty().bind(r.widthProperty());
getChildren().add(r);
}
public void add(Region n) {
HBox.setHgrow(n, Priority.ALWAYS);
getChildren().add(n);
}
}
}
its 2 years but the solution is you forgot
Node.setPrefSize(width,height);
and also add this to your constructor Hbox.setFillHeight(true);
Hi I'm completely new to android programming and use AIDE via tablet.
I'm trying to create a very basic program with a Spinner box that gives output on the selection Ive made via an TextView or System.Out.printIn. (Perhaps the next step up from Hello world - if you will)
For some reason that I cannot fathom,the compiler refuses to recognise the OnClickListener and gives the error message 'Unknown method OnClickListener in Android.Widget.Spinner'
When I have already checked this in the imports.
As a matter of interest I have changed the name of the Spinner and the error seems to dissapear, the problem then is the Spinner name. I have tried several variations on this, and have came to the conclusion that the best option for me is to create a variable just after Main Acivity, and before the layout is declared.
I have also disabled one of the overrides in order to resolve my problem
has anyone got an idea what the problem could be?
package com.BGilbert.AUC;
import android.app.*;
import android.os.*;
import android.widget.*;
import android.view.View.OnClickListener;
import android.widget.Spinner.*;
import android.view.*;
public class MainActivity extends Activity {;
String Fbstring;
OnClickListener Myonclick;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.setContentView(R.layout.main);
final Spinner Fbspinner=(Spinner)findViewById(R.id.Spinner);
// The problem is with this line. OnClickListener just wont be
// recognised
Fbspinner.OnClickListener(Myonclick);
}
// Override previously disabled
#Override
public void Onselect(AdapterView<?> parent,View V, int pos, long id) {
Fbstring = parent.getItemAtPosition(pos).toString();
System.out.println(Fbstring);
}
#Override
public void onNothingSelected(AdapterView<?> arg0) {
}
}
You can't set an onClickListener on a spinner, only on it's views which is too advanced for you at the moment. Instead, use an onItemSelectedListener.
public class MainActivity extends Activity extends Activity implements OnItemSelectedListener {
public void onItemSelected(AdapterView<?> parent, View view,
int pos, long id) {
...
...
}
You should read the documentation first http://developer.android.com/guide/topics/ui/controls/spinner.html
Also try to use standard naming conventions:
http://www.oracle.com/technetwork/java/codeconv-138413.html
http://www.oracle.com/technetwork/java/javase/documentation/codeconventions-135099.html#367
Finally, you have many problems in this code, e.g.
public class MainActivity extends Activity {;
Note the semicolon at the end.
Get your code compiling first, then come back with your next question.
Good luck