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How to wait for changing different imageviews in android?

I'm using this code to change between different images, but the only image that is visualized is the last one. The TextView "vista_aterrizaje" does not show the expected value in each loop.
I have tried to use invalidate() method before the sleep() one, to try to visualize it in each different loop of the for. But it does not work.
establecerImagen() method is used for changing the imageView.
for (int i = 0; i < 15; i++) {
cur_aterrizaje = aterrizajes[rand.nextInt(aterrizajes.length)];
vista_aterrizaje.setText(cur_aterrizaje);
establecerImagen(cur_aterrizaje);
vista_aterrizaje.();
mapa.invalidate();
try{
Thread.sleep(50);
} catch (Exception e) {
e.printStackTrace();
}
}
I think that the problem is in the sleep() method but I don't know how to wait a few seconds after every change of the views in order to visualize every change.

Try using CountDownTimer.
// here interval 1000 stands for 1sec,
//so onTick() will be called 15 times, each call after 1 sec interval. so you can set your own values as per your need.
int i=0;
long interval = 1000;
new CountDownTimer((15 * interval), interval){
#Override
public void onTick(long l) {
vista_aterrizaje.setText(i+"");
establecerImagen(cur_aterrizaje);
i++;
}
#Override
public void onFinish() {
}
}.start();

The parameter to sleep() is in milliseconds. So if you want to show each image for 1 second, the parameter should be 1000.
A better way to do it would be like this:
handler=new Handler();
Runnable r=new Runnable() {
public void run() {
//display your image here -- it will be displayed after a 1-second delay
}
};
handler.postDelayed(r, 1000);

Count integer with Thread in Activity and update Canvas in View

I'm developing my first android game without xml files for layouts in eclipse. This is calling MyGameView.class(extends View) from MyGameActivity.class(extends View implements OnTouchListener)
MyGameView myView;
myView = new MyGameView(this);
myView.setOnTouchListener(this);
setContentView(myView);
Everytime, I touch (MotionEvent.ACTION_DOWN), I update the Canvas in MyGameView.class with the following code. This is the code I use to update MyGameView.class from MyGameActivity.class.
myView.invalidate();
Yes it works!But I got a serious problem now.I need to move Canvas in MyGameView.class by every 0.3 second.I use Thread to update but it forced stop!!!! I tried again and again and again! I failed!
public void runtime() {
i = 0;
Thread timer = new Thread(new Runnable() {
#Override
public void run() {
while (i<1500) {
try {
Thread.sleep(300);
}
catch (InterruptedException e) {
e.printStackTrace();
}
finally {
if (right) {
i++;
//This is static int a from MyGameView.
MyGameView.a += 2;
myView.invalidate();
}
else {
i = 1500;
}
}
}
}
});
timer.start();
}
Updating Static int or boolean to MyGameView.class from MyGameActivity.class with myView.invaldate(); is working. But I can't control it with Thread! Is there something wrong with my Thread running code?
It's probably up to Thread because I can move +2 along X-axis to right everytime I press (MotionEvent.ACTION_DOWN).
//I can Move with this code but not with Thread!
case MotionEvent.ACTION_DOWN:
MyGameView.a += 2;
myView.invalidate();
break;
With Thread, it stops! Please give me a solution for this! In other words, I need to count with time without error and update canvas on every count!

Invalidate must be called from the UI thread. Try calling
postInvalidate()
instead.
See this for reference.

Run Handler Task in Android successively

atm i have a problem with my actual Android application.
For explanation:
At first i want to show a Text in a TextView Char by Char. This is my actual Code for this
tvIntro.setText("");
final Handler textHandler = new Handler();
for(int i=0; i<intro.length();i++){
final int finalCount = i;
textHandler.postDelayed(new Runnable() {
#Override
public void run() {
tvIntro.setText(tvIntro.getText() + (intro.charAt(finalCount)+""));
}
}, 150 * i);
}
After the whole text is displayed, i want to play a sound and continuously change the Color of the Screen for 5 Seconds. For this, my code is:
myBackground.setBackgroundColor(Color.RED);// set initial colour
final Thread blink = new Thread(new Runnable() {
public void run() {
while (getRunning()) {
try {
Thread.sleep(100);
if(start[0] !=1){
mp.start();
start[0] = 1;
}
}
catch (InterruptedException e) {
e.printStackTrace();
}
updateColor(myBackground);
whichColor = !whichColor;
}
}
});
private void updateColor(final RelativeLayout myBackground) {
runOnUiThread(new Runnable() {
#Override
public void run() {
if (whichColor)
myBackground.setBackgroundColor(Color.RED);
else
myBackground.setBackgroundColor(Color.GREEN);
}
});
}
All the functions are working, but i want too finish the first handler, before the second handler is executed. Furthermore the Second handler should stop after x seconds.
I have some problems understanding how the handler and the Threads work.
Would be nice if someone of you have a solution for me.

To delay the performing of tasks until a specified thread (or threads) finishes, add this line immediately after the thread you wish to wait on:
myThread.join();
And then immediately follow it with the code you wish to run after it finishes.
For your second problem, you can set a variable to be the value (in milliseconds) for the amount of time you want to wait before ending the thread, and then decrease that value by 100 (or whatever amount you choose to tell it to sleep for) each time the code runs. Have a check for the value to be less than or equal to zero, and then if that condition returns true, end the thread with an interrupt. So basically:
long timeToRun = 5000, sleepTime = 100;
// Your code here...
Thread.sleep(sleepTime);
timeToRun -= sleepTime;
if(timeToRun <= 0) {
myThread.interrupt();
}
There are likely more graceful ways to accomplish this, but at the very least this should solve your problems.

JProgressBar not working properly

So my JProgressBar I have set up doesn't work the way I want it. So whenever I run the program it just goes from 0 to 100 instantly. I tried using a ProgressMonitor, a Task, and tried a SwingWorker but nothing I tried works.
Here is my program:
int max = 10;
for (int i = 0; i <= max; i++) {
final int progress = (int)Math.round(
100.0 * ((double)i / (double)max)
);
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
Logger.getLogger(BandListGenerator.class.getName()).log(Level.SEVERE, null, ex);
}
jProgressBar2.setValue(progress);
}
});
}
#MadProgrammer Here is my attempt at making a swing worker and writing each name to the document and updating the progress bar. The program gets to around 86 percent and stops, never creating the finished document. The program creates a blank document. Here are the two methods first is the SwingWorker object I made:
public class GreenWorker extends SwingWorker<Object, Object> {
#Override
protected Object doInBackground() throws Exception {
int max = greenList.size();
XWPFParagraph tmpParagraph;
XWPFRun tmpRun;
FileInputStream file =
new FileInputStream(location + "GreenBandList.docx");
gDocument = new XWPFDocument(OPCPackage.open(file));
for (int i = 0; i < max; i++) {
tmpParagraph = gDocument.getParagraphs().get(0);
tmpRun = tmpParagraph.createRun();
if (greenList.get(i).length() == 1) {
tmpRun.setBold(true);
tmpRun.setText(greenList.get(i));
tmpRun.setBold(false);
} else {
tmpRun.setText(greenList.get(i));//Write the names to the Word Doc
}
int progress = Math.round(((float) i / max) * 100f);
setProgress(progress);
}
return null;
}
}
And here is the code for the button that starts it and has my property change event.
private void GenerateGreenList() throws IOException, InterruptedException {
//Need to fix the bug that removes the Letter Header in Yellow Band list
//********************************************************************\\
//Delete the old list and make a new one
File templateFile = new File(location + "\\backup\\GreenTemplate.docx");
FileUtils.deleteQuietly(new File(location + "GreenBandList.docx"));
FileUtils.copyFile(templateFile, new File(location +
"GreenBandList.docx"));
//Get the New Entries
String[] entries = jTextPane3.getText().split("\n");
for (String s : entries) {
if (s != null) {
greenList.add(s);
}
}
//Resort the list
Collections.sort(greenList);
//Write the names to the document
GreenWorker worker = new GreenWorker();
worker.addPropertyChangeListener(new PropertyChangeListener() {
#Override
public void propertyChange(PropertyChangeEvent evt) {
if ("progress".equals(evt.getPropertyName())) {
jProgressBar2.setValue((Integer) evt.getNewValue());
}
}
});
worker.execute();
if (worker.isDone()) {
try {
gDocument.write(new FileOutputStream(new File(location + "GreenBandList.docx")));
////////////////////////////////////////////////////////////
} catch (IOException ex) {
Logger.getLogger(BandListGenerator.class.getName()).log(Level.SEVERE, null, ex);
}
JOptionPane.showMessageDialog(null, "Green Band List Created!");
jProgressBar2.setValue(0);
}
}
I used the property change listener from one of your other posts but I don't really understand what the one you wrote does or what it does in general?

Swing is a single threaded environment, that is, there is a single thread which is responsible for processing all the events that occur within the system, including repaint events. Should anything block this thread for any reason, it will prevent Swing from processing any new events, including, repaint events...
So all this ...
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
Logger.getLogger(BandListGenerator.class.getName()).log(Level.SEVERE, null, ex); }
jProgressBar2.setValue(progress);
}
});
Is constantly pausing the Event Dispatching Thread, preventing it from actually doing any updates (or at least spacing them randomly)...
It's also likely that your outer loop is been run from within the context of the EDT, meaning that until it exists, nothing in the Event Queue will be processed. All your repaint requests will be consolidated down to a single paint request and voila, instant filled progress bar...
You really should use a SwingWorker - I know you said you tried one, but you've not shown any code as to your attempt in this regards, so it's difficult to know why it didn't work, however...
SwingWorker and JProgressBar example
SwingWorker and JProgressBar example
SwingWorker and JProgressBar example
SwingWorker and JProgressBar example
SwingWorker and dual welding JProgressBar example
SwingWorker and JProgressBar example
And forgive me if we haven't said this a few times before :P

You are evoking Thread.sleep inside the EvokeLater which means that it is running on another thread than your for loop. i.e., your for loop is completing instantaneously (well, however long it takes to loop from 1 to 100, which is almost instantaneously).
Move Thread.sleep outside of EvokeLater and it should work as you intend.
int max = 10;
for (int i = 0; i <= max; i++) {
final int progress = (int)Math.round(
100.0 * ((double)i / (double)max)
);
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
jProgressBar2.setValue(progress);
}
});
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
Logger.getLogger(BandListGenerator.class.getName()).log(Level.SEVERE, null, ex);
}
}
Edit: agree with #MadProgrammer. It appears this is just an illustrative question, but you should make sure whatever you're trying to accomplish here you use a SwingWorker for.

Rectangle colouring logic

I have one three rectangles in my canvas. I wanted to change the colours of three rectangles
in a slow manner one by one.
For example: When starting the application, user should be able to see three rectangles with the same colour (blue).
After 2 secons that rectangles colour should change to red.
Again after 2 secons the next rectangles colour should get changed.
The last one is also done the same way, that means after 2 seconds of the 2nd rectangle.
I wrote in my own way. But it is not working. All the rectanlges are changed together. I want one by one.
Could anyone give me the logic.
final Runnable timer = new Runnable() {
public void run() {
//list of rectangles size =3; each contain Rectangle.
for(int i = 0 ; i < rectangleList.size();i++){
if(rectangleListt.get(i).getBackgroundColor().equals(ColorConstants.blue)){
try {
rectangleList.get(i).setBackgroundColor(ColorConstants.yellow);
Thread.sleep(1500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//rectSubFigureList.get(i).setBorder(null);
}/*else{
rectSubFigureList.get(i).setBackgroundColor(ColorConstants.blue);
}*/
}

You're likely calling Thread.sleep inside of Swing's event thread or EDT (for event dispatch thread), and this will cause the thread itself to sleep. Since this thread is responsible for all of Swing's graphics and user interactions, this will in effect put your entire application to sleep, and is not what you want to have happen. Instead, read up on and use a Swing Timer for this.
References:
Swing Timer tutorial
Swing Event Dispatch Thread and Swingworker tutorial
To expand on Hidde's code, you could do:
// the timer:
Timer t = new Timer(2000, new ActionListener() {
private int changed = 0; // better to keep this private and in the class
#Override
public void actionPerformed(ActionEvent e) {
if (changed < rectangleList.size()) {
rectangleList.setBackgroundColor(someColor);
} else {
((Timer) e.getSource()).stop();
}
changed++;
}
});
t.start();

You can set a Timer:
// declaration:
static int changed = 0;
// the timer:
Timer t = new Timer(2000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// Change the colour here:
if (changed == 0) {
// change the first one
} else if (changed == 1) {
// change the second one
} else if (changed == 2) {
// change the last one
} else {
((Timer) e.getSource()).stop();
}
changed ++;
}
});
t.start();