LWUIT TextArea NullPointerException - java-me

I run LWUITDemo, Some UI can not be shown successful.All of them are TextArea contained by Form.If I change TextArea to Label, it work well.
Sorry, I run it in nokia s40 sdk 2.0. When I run most of codes that include TextArea, exception ocurred;
The Code Like That(From LWUITDemo):
Form aboutForm = new Form("About");
aboutForm.setScrollable(true);
aboutForm.setLayout(new BorderLayout());
TextArea aboutText = new TextArea(getAboutText(), 5, 10);
aboutText.setEditable(false);
aboutForm.addComponent(BorderLayout.CENTER, aboutText);
aboutForm.show();
When I run it, it faild:
Form: showModal
java.lang.NullPointerException
at com.sun.lwuit.TextArea.shouldShowHint(+21)
at com.sun.lwuit.TextArea.calcPreferredSize(+4)
at com.sun.lwuit.Component.preferredSize(+63)
...

You Could Check below Code:
import com.sun.lwuit.Display;
import com.sun.lwuit.Form;
import com.sun.lwuit.TextArea;
import com.sun.lwuit.layouts.BorderLayout;
import javax.microedition.midlet.*;
public class TextMidlet extends MIDlet {
private Form aboutForm;
public TextMidlet() {
Display.init(this);
aboutForm = new Form();
aboutForm.setScrollable(true);
aboutForm.setLayout(new BorderLayout());
}
public void startApp() {
TextArea aboutText = new TextArea("hiiiiiiiiiiiiii", 5, 10);
aboutText.setEditable(false);
aboutForm.addComponent(BorderLayout.CENTER, aboutText);
aboutForm.show();
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
}

The code looks good to me. Please check that getAboutText() returns a String and does not return null.
If this does not help, you can use the LWUIT-Sources to debug your code. Set a breakpoint at TextArea.shouldShowHint and find out what it is that is null.

Check
import com.sun.lwuit.TextArea;

Related

setText() not reflecting changes when called from another thread

I am a beginner in javaFX and am stuck in this one area. Any help will be appreciated a lot.
This is sample app I have made for clear understanding using scene builder. There is a text area and a button.I want to set data into the text area on the button click. The setting happens in another thread.
The code is as follows:
import java.net.URL;
import java.util.ResourceBundle;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.*;
import javafx.stage.Stage;
public class TpController{
#FXML
private ScrollPane scrollPane;
#FXML
private Button button;
#FXML
public TextArea txtArea ;
private Stage stage;
public void setTextArea(TextArea txt)
{
this.txtArea = txt ;
}
public TextArea getTextArea()
{
return txtArea;
}
public void setStage(Stage stage)
{
this.stage = stage;
}
public Stage getStage()
{
return stage;
}
public void setTopText(String text) {
// set text from another class
txtArea.setText(text);
}
public void buttonHandler()
{
tpThread t = new tpThread();
t.start();
}
The tpThread class is as follows:
import java.io.IOException;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.control.TextArea;
import javafx.stage.Stage;
public class tpThread extends Thread {
#Override
public void run() {
// TODO Auto-generated method stub
FXMLLoader loader = new FXMLLoader(getClass().getResource("Justtp.fxml"));
try {
Parent root = (Parent) loader.load();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
TpController myController = loader.getController();
TextArea t = myController.getTextArea();
String data = "hi\nhello\nhow are you\nnice to meet you\nhahaha";
//System.out.println(t.setData("hi"));
myController.setTopText(data);
}
Instead of using setTopText, i have also directly used
t.setText(data);
But no use. My final output does nothing on the button click.
There are many issues with your code.
Modifications to the active scene graph off of the JavaFX application thread must be performed via Platform.runLater().
You don't need another thread to accomplish something on a button click.
You can just define an action handler for the button using setOnAction().
Event handler methods on controllers can also be cross-referenced in FXML via onAction="#handleButtonAction" where handleButtonAction is defined as a public void handleButtonAction(ActionEvent event) method in your controller.
All event handlers are invoked by the JavaFX runtime on the JavaFX application thread, so you don't need to worry about multi-threading when writing event handlers - the JavaFX event handling programming model is single threaded.
Loading an FXML as you do in your code and not attaching the resultant node to a scene is pointless as the user will never see anything that is not attached to a scene.
There may be other issues with your code which cause it not to work as you expect.
In general, for assistance debugging an issue, provide an mcve. Note it should be both minimal and complete so that somebody could copy and paste the code to replicate the issue (and pretty much nothing else).

JavaFx 2.x : Stage within a TabPane

I need to display one or more stage(s) within a TabPane by clicking on a button, such as the picture below
My target is to have a situation similar to JInternalFrame in Swing: how to accomplish this?
I am not able to add stage as children to the tab pane.
If this is not possible, what could be other solutions? I would like to have SplitPanes on the stage.
Thanks
PS I am using Win7, NetBeans 7.4 Beta (Build 201307092200), SceneBuilder 1.1
Edit: here is how it looks after some VFXWindows css changes
There's one thing worth notice: I have had to add a node ( in my case an HBox with prefSize(0,0), otherwise I can't move o resize the first window plotted, only the first one.
As last, I can't find a way to set windows full screen (maximize).
Here I put an example of windows from jfxtras inside of Tabs, I just modify the example.
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.Tab;
import javafx.scene.control.TabPane;
import javafx.stage.Stage;
import jfxtras.labs.scene.control.window.CloseIcon;
import jfxtras.labs.scene.control.window.MinimizeIcon;
import jfxtras.labs.scene.control.window.Window;
public class WindowInTab extends Application {
private static int counter = 1;
private void init(Stage primaryStage) {
TabPane tabPane = new TabPane();
Tab tab = generateTab("Windows...");
Tab anotherTab = generateTab("More Windows");
tabPane.getTabs().addAll(tab, anotherTab);
primaryStage.setResizable(true);
primaryStage.setScene(new Scene(tabPane, 600, 500));
}
private Tab generateTab(String tabName) {
Tab tab = new Tab(tabName);
final Group root = new Group();
tab.setContent(root);
Button button = new Button("Add more windows");
root.getChildren().addAll(button);
button.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent arg0) {
// create a window with title "My Window"
Window w = new Window("My Window#"+counter);
// set the window position to 10,10 (coordinates inside canvas)
w.setLayoutX(10);
w.setLayoutY(10);
// define the initial window size
w.setPrefSize(300, 200);
// either to the left
w.getLeftIcons().add(new CloseIcon(w));
// .. or to the right
w.getRightIcons().add(new MinimizeIcon(w));
// add some content
w.getContentPane().getChildren().add(new Label("Content... \nof the window#"+counter++));
// add the window to the canvas
root.getChildren().add(w);
}
});
return tab;
}
public double getSampleWidth() {return 600;}
public double getSampleHeight() {return 500;}
#Override
public void start(Stage primaryStage) throws Exception {
init(primaryStage);
primaryStage.show();
}
public static void main(String[] args) {launch(args);}
}
I don't know if this was exactly what you were looking for. Hope it helps!

Why Android libslide menu with actionbarsherlock open automatically?

I have a project with the sliding menu (from jeremy feinstein) and actionbarsherlock.
For some reason, when the activity shows up the slide menu open automatically too.
Quick note about my app architecture:
All of my activities have the slide menu integrated and on menu item click I start the related activity (with FLAG_ACTIVITY_SINGLE_TOP).
All my activities extends the class shown below.
This is quite annoying because every time the user click on one item, the menu get expanded as well forcing the user to close it down.
Anyone knows what it is causing this behavior?
What should I do to fix it and have the expected behavior.
I post below the concerned code:
package com.example.mypapp;
import com.example.mypapp.R;
import ocom.example.mypapp.SampleListFragment;
import android.os.Bundle;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.ListFragment;
import com.actionbarsherlock.view.Menu;
import com.actionbarsherlock.view.MenuItem;
import com.jeremyfeinstein.slidingmenu.lib.SlidingMenu;
import com.jeremyfeinstein.slidingmenu.lib.app.SlidingFragmentActivity;
public class MyAppBaseActivity extends SlidingFragmentActivity {
protected ListFragment mFrag;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setBehindContentView(R.layout.menu_frame);
SlidingMenu sm = getSlidingMenu();
sm.setShadowWidthRes(R.dimen.shadow_width);
sm.setShadowDrawable(R.drawable.shadow);
sm.setBehindOffsetRes(R.dimen.slidingmenu_offset);
sm.setFadeDegree(0.35f);
sm.setTouchModeAbove(SlidingMenu.TOUCHMODE_FULLSCREEN);
if (savedInstanceState == null) {
FragmentTransaction t = this.getSupportFragmentManager().beginTransaction();
mFrag = new SampleListFragment();
t.replace(R.id.menu_frame, mFrag);
t.commit();
} else {
mFrag = (ListFragment)this.getSupportFragmentManager().findFragmentById(R.id.menu_frame);
}
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == android.R.id.home) {
toggle();
}
return true;
}
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
toggle();
return true;
}
}
Where SlidingFragmentActivity has been modified to extend SherlockFragmentActivity as suggested on official page of Jeremy Feinstein when actionbarsherlock is also in the picture.

Lwuit touch screen strange behaviour

I am making an application using LWUIT.
There is a form
There is a list embedded on the form.
The list has 5 elements.
Initially, when I first load the app, if I choose the 1st element, 2nd gets chosen; when I choose the second the 3rd gets chose and and so on (Weird!)
I am not able to click any button on the screen either
next what I do is, shift to a different from using arrow keys (of the keyboard... I am running the app on a simulator btw)
Then I come back to the first form and now everything works as expected(no weird behaviour).
What could be the issue?
I am using Sun Java Micro Edition SDK 3.0 (default touch screen for testing)
My code is:
List dummy = new List();
dummy.addItem("wewerwer");
dummy.addItem("wewerdswer");
dummy.addItem("wewqweerwer");
dummy.addItem("dscxwewerwer");
dummy.addItem("jhgwewerwer");
mainListForm.setLayout(new BorderLayout());
mainListForm.addComponent(BorderLayout.CENTER,dummy);
mainListForm.show();
What could possible be going wrong here?
UPDATE 1
I think there is a bug here. I have attached the complete code below along with the screen shot
import javax.microedition.midlet.*;
import com.sun.lwuit.*;
import com.sun.lwuit.events.*;
import com.sun.lwuit.plaf.UIManager;
import com.sun.lwuit.util.Resources;
public class Demo extends MIDlet implements ActionListener {
private Form mForm;
List abc;
public void startApp() {
Display.init(this);
try {
Resources r = Resources.open("/Test.res");
UIManager.getInstance().setThemeProps(r.getTheme(
r.getThemeResourceNames()[0])
);
} catch (Exception e){
System.out.println(e.toString());
}
if (mForm == null) {
Button click = new Button("Press me!");
click.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
System.out.println("I have been pressed");
}
});
abc = new List();
abc.addItem("Str1");
abc.addItem("Str2");
abc.addItem("Str3");
abc.addItem("Str4");
abc.addItem("Str5");
abc.addItem("Str6");
Form f = new Form("Hello, LWUIT!");
abc.addActionListener(this);
f.addComponent(abc);
Command exitCommand = new Command("Exit");
f.addCommand(exitCommand);
f.addCommandListener(this);
f.addComponent(click);
f.show();
}
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void actionPerformed(ActionEvent ae) {
System.out.println(abc.getSelectedIndex());
}
}
So now when I click on 'Str1' of the list Str2 gets selected and so on.
IDE: Netbeans
Emulator: Default Touch screen phone
On the action event set the list to active again after the event by invoking setHandlesInput(true)
OK....so this is how you resolve it.
After the form is displayed remove the list from the form and again add it to the form and then repaint the form.
Earlier Code
1) form.addComponenet(BorderLayout.center,list);
2) form.show();
Word Around for the problem
1)form.addComponenet(BorderLayout.center,list);
2)form.show();
3)form.setScrollable(false);
I know its kind of strange, but this way the list index selection works smooth for touch screen phones.

LWUIT assistance

import com.sun.lwuit.Button;
import com.sun.lwuit.Command;
import com.sun.lwuit.Display;
import com.sun.lwuit.Label;
import com.sun.lwuit.events.ActionEvent;
import com.sun.lwuit.events.ActionListener;
import com.sun.lwuit.layouts.BorderLayout;
import com.sun.lwuit.plaf.UIManager;
import com.sun.lwuit.util.Resources;
import java.io.IOException;
public class Ruwwa extends javax.microedition.midlet.MIDlet
implements ActionListener{
Form f;
Button mybutton1;
Button mybutton2;
Command exit;
Command ok;
public void startApp() {
Display.init(this);
f = new Form();
try {
Resources r = Resources.open("/mairuwa.res");
UIManager.getInstance().setThemeProps(r.getTheme("Mairuwa Theme"));
} catch (IOException ioe) {
ioe.printStackTrace();
}
mybutton1=new Button("Report A Problem");
mybutton2=new Button("Request Info");
f.setLayout(new BorderLayout());
f.addComponent(BorderLayout.CENTER, new Label("The Mairuwa Portal"));
ok = new Command("OK");
exit = new Command("Exit");
f.addCommand(ok);
f.addCommand(exit);
f.addCommandListener(this);
f.show();
}
public void pauseApp() {}
public void destroyApp(boolean unconditional) {}
public void actionPerformed(ActionEvent ae) {
notifyDestroyed();
}
}
I would like to add another label under the "The Mairuwa Portal" and also place two buttons ("Report A Problem","Request Information") beneath this as well. An illustration of what I am describing is
label: The Mairuwa Portal
then another label beneath it: I want to:
Then two buttons beneath this Button:Report Problem Button: Request Information
I have been able to add OK and EXIT button to the project,but this above buttons I talked about should as I described.
These buttons will carry functionality. I hope this can be done in LWUIT.
You need to include all JSR's when compiling a LWUIT application in the IDE. LWUIT doesn't require them all to run but requires 184, 226, MMAPI & file connector to compile. This is causing your verification error.
I would recommend developing with the Sun/Oracle simulators and using the more device like emulators for QA.
The exception you got means your application was built incorrectly, see that Ruwwa is in the jar file that was produced by your build. If not fix your build.

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