Integer number as condition - Android studio - android-studio

Good morning. I would like to ask how Can i check if the number is integer or it isn't? I work in AndroidStudio and wanted to check this condition. I've written smth like this but with no success.Application crashes.
int value = 0;
if (!et.equals(temp)) {
value = Integer.parseInt(temp);
}
if (value != 0 && value < 10 && value > 1 && (value -(int)value!=0)) {

You can check it like this:
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String inputNumber = editText.getText().toString();
if (inputNumber.contains(".")) {
editText.setError("Your Error Message Here");
} else {
int num = Integer.parseInt(inputNumber);
// you got your interger ...
}
}
});
And use android:inputType="numberDecimal" in your EditText .

Related

How to have different color brushes using multi touch?

I am trying to make it so each finger on the screen has a different color as it paints its path. I am using pointers to create the path and toyed with assigning the pointer IDs a different color per number but no result. In the code below I am trying to make the first finger blue then when another finger begins drawing it would turn red. Currently the code makes all the paint blue but when 3 fingers are on the screen it all changes red. Any help is appreciated thank you
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if(idColor == 1)
mFingerPaint.setColor(Color.BLUE);
if(idColor == 2)
mFingerPaint.setColor(Color.RED);
for (Path completedPath : mCompletedPaths) {
canvas.drawPath(completedPath, mFingerPaint);
}
for (Path fingerPath : mFingerPaths) {
if (fingerPath != null) {
canvas.drawPath(fingerPath, mFingerPaint);
}
}
}
public boolean onTouchEvent(MotionEvent event) {
int pointerCount = event.getPointerCount();
int cappedPointerCount = pointerCount > MAX_FINGERS ? MAX_FINGERS : pointerCount;
// get pointer index from the event object
int actionIndex = event.getActionIndex();
// get masked (not specific to a pointer) action
int action = event.getActionMasked();
// get pointer ID
int id = event.getPointerId(actionIndex);
idColor = id;
if ((action == MotionEvent.ACTION_DOWN || action == MotionEvent.ACTION_POINTER_DOWN) && id < MAX_FINGERS)
{
mFingerPaths[id] = new Path();
mFingerPaths[id].moveTo(event.getX(actionIndex), event.getY(actionIndex));
}
else if ((action == MotionEvent.ACTION_POINTER_UP || action == MotionEvent.ACTION_UP) && id < MAX_FINGERS)
{
mFingerPaths[id].setLastPoint(event.getX(actionIndex), event.getY(actionIndex));
mCompletedPaths.add(mFingerPaths[id]);
mFingerPaths[id].computeBounds(mPathBounds, true);
invalidate((int) mPathBounds.left, (int) mPathBounds.top, (int) mPathBounds.right, (int) mPathBounds.bottom);
mFingerPaths[id] = null;
}
for(int i = 0; i < cappedPointerCount; i++) {
if(mFingerPaths[i] != null)
{
int index = event.findPointerIndex(i);
mFingerPaths[i].lineTo(event.getX(index), event.getY(index));
mFingerPaths[i].computeBounds(mPathBounds, true);
invalidate((int) mPathBounds.left, (int) mPathBounds.top, (int) mPathBounds.right, (int) mPathBounds.bottom);
}
}
return true;
}
}

What does "isRtlSupported && 1" mean?

In ConstraintLayout , there is some codes written below:
protected boolean isRtl() {
if (android.os.Build.VERSION.SDK_INT >= 17) {
boolean isRtlSupported = (this.getContext().getApplicationInfo().flags & 4194304) != 0;
return isRtlSupported && 1 == this.getLayoutDirection();
} else {
return false;
}
}
And I copy this to my custom layout, Android Studio cannot read the "1" in && 1 .
Why a boolean can && a int ?
Sorry, it should be read as follows
return isRtlSupported && (1 == this.getLayoutDirection());
Here 1 is replaced by View.LAYOUT_DIRECTION_RTL works fine.
i.e.
return isRtlSupported && (View.LAYOUT_DIRECTION_RTL == this.getLayoutDirection());
where
public static final int LAYOUT_DIRECTION_RTL = LayoutDirection.RTL;
in View.java
and
public static final int RTL = 1;
in LayoutDirection.java

Sound won't play at a specific time in unity

I am trying to make a sound play with the timer goes to 3, 2, 1.
My timer starts at ten and has a three second delay. If I use the following code:
if (tl.myCoolTimer == 10)
{
print("Play Sound");
myAudioSource.Play();
}
It plays the Beep over and over again until the game starts and the counter goes below 10.
If I use the code:
if (tl.myCoolTimer == 3)
{
print("Play Sound");
myAudioSource.Play();
}
It doesn't play the sound at all. It doesn't even print the print statement.
I literally only changed the number. I am not sure why this isn't working.
I have also tried setting it to 3f to see if it is a float issue.
Timer Scripts
This is the starting Timer. it counts down to 3 (then the game starts)
public Text startGameTimerText;
public float startGameTimer = 3;
public void Start ()
{
startGameTimerText = GetComponent<Text> ();
}
public void Update ()
{
startGameTimer -= Time.deltaTime;
startGameTimerText.text = startGameTimer.ToString ("f1");
if (startGameTimer < 0) {
GameObject.Find ("GameStartTimer").SetActive (false);
}
}
This is the Game Timer It starts at 10 and counts down to 0.
public StartGameTimer gt; //this is the script the other timer is on
public Text timerText;
public float myCoolTimer = 10;
public void Start ()
{
timerText = GetComponent<Text> ();
}
public void Update ()
{
if (gt.startGameTimer > 0) {
myCoolTimer = 10;
} else {
myCoolTimer -= Time.deltaTime;
timerText.text = myCoolTimer.ToString ("f1");
}
}
Thanks Joe for the help. Here was my final answer. I know it is hacked, but I haven't figured out the Invoke thing yet. When I set the into it kept playing the entire time it was at "3", so i need to make it play only once.
private AudioSource myAudioSource;
public bool isSoundPlayed;
void Start()
{
myAudioSource = GetComponent<AudioSource>();
isSoundPlayed = false;
}
void Update()
{
if((int)tl.myCoolTimer == 3)
{
if (isSoundPlayed == false)
{
myAudioSource.Play();
isSoundPlayed = true;
}
return;
}
if ((int)tl.myCoolTimer == 2)
{
if (isSoundPlayed == true)
{
myAudioSource.Play();
isSoundPlayed = false;
}
return;
}
if ((int)tl.myCoolTimer == 1)
{
if (isSoundPlayed == false)
{
myAudioSource.Play();
isSoundPlayed = true;
}
return;
}
}

How to avoid java.util.NoSuchElementException

The code below is giving me the error java.util.NoSuchElementException right after I Ctrl+Z
to indicate that the user input is complete. By the looks of it seems as if it does not know how to just end one method without messing with the other scanner object.
I try the hasNext method and I ended up with an infinite loop, either way is not working. As a requirement for this assignment I need to be able to tell the user to use Ctrl+Z or D depending on the operating system. Also I need to be able to read from a text file and save the final tree to a text file please help.
/* sample input:
CSCI3320
project
personal
1 HW1
1 HW2
1 2 MSS.java
2 p1.java
*/
import java.util.Scanner;
import java.util.StringTokenizer;
public class Directory {
private static TreeNode root = new TreeNode("/", null, null);
public static void main(String[] args) {
userMenu();
System.out.println("The directory is displayed as follows:");
root.listAll(0);
}
private static void userMenu(){ //Displays users menu
Scanner userInput = new Scanner(System.in);//Scanner option
int option = 0;
do{ //I believe the problem is here since I am not using userInput.Next()
System.out.println("\n 1. add files from user inputs ");
System.out.println("\n 2. display the whole directory ");
System.out.println("\n 3. display the size of directory ");
System.out.println("\n 0. exit");
System.out.println("\n Please give a selection [0-3]: ");
option = userInput.nextInt();
switch(option){
case 1: addFileFromUser();
break;
case 2: System.out.println("The directory is displayed as follows:");
root.listAll(0);
break;
case 3: System.out.printf("The size of the directory is %d.\n", root.size());
break;
default:
break;
}
}while( option !=0);
userInput.close();
}
private static void addFileFromUser() {
System.out.println("To terminate inp1ut, type the correct end-of-file indicator ");
System.out.println("when you are prompted to enter input.");
System.out.println("On UNIX/Linux/Mac OS X type <ctrl> d");
System.out.println("On Windows type <ctrl> z");
Scanner input = new Scanner(System.in);
while (input.hasNext()) { //hasNext being used Crtl Z is required to break
addFileIntoDirectory(input); // out of the loop.
}
input.close();
}
private static void addFileIntoDirectory(Scanner input) {
String line = input.nextLine();
if (line.trim().equals("")) return;
StringTokenizer tokens = new StringTokenizer(line);
int n = tokens.countTokens() - 1;
TreeNode p = root;
while (n > 0 && p.isDirectory()) {
int a = Integer.valueOf( tokens.nextToken() );
p = p.getFirstChild();
while (a > 1 && p != null) {
p = p.getNextSibling();
a--;
}
n--;
}
String name = tokens.nextToken();
TreeNode newNode = new TreeNode(name, null, null);
if (p.getFirstChild() == null) {
p.setFirstChild(newNode);
}
else {
p = p.getFirstChild();
while (p.getNextSibling() != null) {
p = p.getNextSibling();
}
p.setNextSibling(newNode);
}
}
private static class TreeNode {
private String element;
private TreeNode firstChild;
private TreeNode nextSibling;
public TreeNode(String e, TreeNode f, TreeNode s) {
setElement(e);
setFirstChild(f);
setNextSibling(s);
}
public void listAll(int i) {
for (int k = 0; k < i; k++) {
System.out.print('\t');
}
System.out.println(getElement());
if (isDirectory()) {
TreeNode t = getFirstChild();
while (t != null) {
t.listAll(i+1);
t = t.getNextSibling();
}
}
}
public int size() {
int s = 1;
if (isDirectory()) {
TreeNode t = getFirstChild();
while (t != null) {
s += t.size();
t = t.getNextSibling();
}
}
return s;
}
public void setElement(String e) {
element = e;
}
public String getElement() {
return element;
}
public boolean isDirectory() {
return getFirstChild() != null;
}
public void setFirstChild(TreeNode f) {
firstChild = f;
}
public TreeNode getFirstChild() {
return firstChild;
}
public void setNextSibling(TreeNode s) {
nextSibling = s;
}
public TreeNode getNextSibling() {
return nextSibling;
}
}
}
Exception Details:
/*Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Scanner.java:907)
at java.util.Scanner.next(Scanner.java:1530)
at java.util.Scanner.nextInt(Scanner.java:2160)
at java.util.Scanner.nextInt(Scanner.java:2119)
at Directory.userMenu(Directory.java:36)
at Directory.main(Directory.java:21)*/
Your problem is this line:
option = userInput.nextInt(); //line 24
If you read the Javadoc, you will find that the nextInt() method can throw a NoSuchElementException if the input is exhausted. In other words, there is no next integer to get. Why is this happening in your code? Because you this line is in a loop once that first iteration completes (on the outer while loop) your initial input selection has been consumed. Since this is a homework, I am not going to write the code. But, if you remove the loop, you know this works at least once. Once you try to loop, it breaks. So I will give you these hints:
Change the do/while to a while loop.
Prompt the user once outside the loop.
Recreate the prompt and recapture the user input inside the loop.
For example, the code below can be used for the basis of your outer loop.
import java.util.Scanner;
public class GuessNumberGame {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("Guess the secret number: (Hint: the secret number is 1)");
int guess = input.nextInt();
while (guess != 1) {
System.out.println("Wrong guess. Try again: ");
guess = input.nextInt();
}
System.out.println("Success");
input.close();
}
}
The reason why this works is because I don't reuse the same, exhausted, scanner input object to get the next integer. In your example, the initial input is inside the loop. The second time around, that input has already been consumed. Follow this pattern and you should be able to complete your assignment.

Validation in swt text

I would like to validate numbers input in text box.
I want the user to input only integer, decimal in the box between a maximum and minimum values.
How can I make sure of this?
Thank you.
Use a VerifyListener as this will handle paste, backspace, replace.....
E.g.
text.addVerifyListener(new VerifyListener() {
#Override
public void verifyText(VerifyEvent e) {
final String oldS = text.getText();
final String newS = oldS.substring(0, e.start) + e.text + oldS.substring(e.end);
try {
BigDecimal bd = new BigDecimal(newS);
// value is decimal
// Test value range
} catch (final NumberFormatException numberFormatException) {
// value is not decimal
e.doit = false;
}
}
});
You can register a ModifyListener with the text control and use it to validate the number.
txt.addModifyListener(new ModifyListener() {
#Override
public void modifyText(ModifyEvent event) {
String txt = ((Text) event.getSource()).getText();
try {
int num = Integer.parseInt(txt);
// Checks on num
} catch (NumberFormatException e) {
// Show error
}
}
});
You could also use addVerifyListener to prevent certain characters being entered. In the event passed into that method there is a "doit" field. If you set that to false it prevents the current edit.
Integer validation in SWT
text = new Text(this, SWT.BORDER);
text.setLayoutData(gridData);
s=text.getText();
this.setLayout(new GridLayout());
text.addListener(SWT.Verify, new Listener() {
public void handleEvent(Event e) {
String string = e.text;
char[] chars = new char[string.length()];
string.getChars(0, chars.length, chars, 0);
for (int i = 0; i < chars.length; i++) {
if (!('0' <= chars[i] && chars[i] <= '9')) {
e.doit = false;
return;
}
}
}
});
If you only want to allow Integer values you could use a Spinner instead of a text field.
For the validation of Double values you have to consider that characters like E may be included in Doubles and that partial input like "4e-" should be valid while typing. Such partial expressions will give a NumberFormatException for Double.parseDouble(partialExpression)
Also see my answer at following related question:
How to set a Mask to a SWT Text to only allow Decimals
1.create a utill class implement verify listener
2.override verifytext method
3.implement your logic
4.create a object of utill class where you want to use verify listener (on text)
5.text.addverifylistener(utillclassobject)
Example :-
1. utill class:-
public class UtillVerifyListener implements VerifyListener {
#Override
public void verifyText(VerifyEvent e) {
// Get the source widget
Text source = (Text) e.getSource();
// Get the text
final String oldS = source.getText();
final String newS = oldS.substring(0, e.start) + e.text + oldS.substring(e.end);
try {
BigDecimal bd = new BigDecimal(newS);
// value is decimal
// Test value range
} catch (final NumberFormatException numberFormatException) {
// value is not decimal
e.doit = false;
}
}
2.use of verifylistener in other class
public class TestVerifyListenerOne {
public void createContents(Composite parent){
UtillVerifyListener listener=new UtillVerifyListener();
textOne = new Text(composite, SWT.BORDER);
textOne .setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, false, 1, 1));
textOne .addVerifyListener(listener)
textTwo = new Text(composite, SWT.BORDER);
textTwo .setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, false, 1, 1));
textTwo .addVerifyListener(listener);
}
}
text.addVerifyListener(new VerifyListener() {
#Override
public void verifyText(VerifyEvent e) {
Text text = (Text) e.getSource();
final String oldS = text.getText();
String newS = oldS.substring(0, e.start) + e.text + oldS.substring(e.end);
boolean isValid = true;
try {
if(! "".equals(newS)){
Float.parseFloat(newS);
}
} catch (NumberFormatException ex) {
isValid = false;
}
e.doit = isValid;
}
});

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