http://imgur.com/DzTRV2D
In android application i have code like below
private boolean isSpinnerNotChoose(Spinner spinner)
{
if(spinner.getSelectedItem().toString().equals(""))
{
return false;
}
return true;
}
But after many tries even if condition is completed it firstly enter on return false and later anyway debbugger goes on return true (If something stays after brackets its skipped but return true always is done. In link is image how its look after if is completed.
Anyone can answer me for that situation ?
Thanks in advance :)
Better use a boolean and return the boolean once.
The boolean is initially set to true.
It will remain true, if no match happens.
If there's a match, it will change to false.
Then the boolean will be returned (true if no match happens, false if there's a match).
No ghost responses.
I also added a trim(), to cut away the eventual trailing spaces.
Try:
private boolean isSpinnerNotChoose(Spinner spinner)
{
boolean myValue = true; // default return value
if(spinner.getSelectedItem().toString().trim().equals(""))
{
myValue = false;
}
return myValue; // return once and for all
}
Related
I want to check that Rectangle was tapped. This mehod does the job and it works almost how I want:
private bool CheckRectangleTouch(Rectangle target)
{
var touchCollection = TouchPanel.GetState();
if (touchCollection.Count > 0)
{
foreach (var touch in touchCollection)
{
if (target.Contains(touch.Position))
{
return true;
}
}
}
return false;
}
Problem I have is that after I've tapped rectangle it keeps returning true until I release it (it can register 10-30 times for one tap) and I want it to return true just once - for the first touch.
I've tried this (replace code inside foreach):
var isFirstTouch = !touch.TryGetPreviousLocation(out _);
if (target.Contains(touch.Position) && isFirstTouch)
{
return true;
}
And this (bad one, I don't really want it to register after release):
if (target.Contains(touch.Position) && touch.State == TouchLocationState.Released)
{
return true;
}
But nothing is does it. Either logic is not consistent or doesn't work at all.
So how do I check for tap?
Update: this works but it's very hacky, has delay and gives me random phantom taps:
try
{
var tap = TouchPanel.ReadGesture(); // falls each time when no input
return tap.GestureType == GestureType.Tap && target.Contains(tap.Position);
}
catch { }
return false;
Here's what I ended up doing:
I have singleton to hold my game state (many different props updated as needed). I added to it:
public TouchCollection TouchCollection { get; set; }
Prop to hold TouchPanel.GetState result. I fill it in Games Update method once per frame, as #craftworkgames suggested:
State.TouchCollection = TouchPanel.GetState();
Also I added this prop to my game state:
public bool TouchActive { get; set; }
And this is the method to check for rectangle tap. It returns true only for the first contact in tap:
private bool CheckRectangleTap(Rectangle target)
{
if (State.TouchCollection.Count == 0)
{ // if no input
return State.TouchActive = false;
}
var targetTouched = false;
foreach (var touch in State.TouchCollection)
{
if (target.Contains(touch.Position))
{
targetTouched = true;
}
}
if (targetTouched && !State.TouchActive)
{ // if target is touched and it's first contact
return State.TouchActive = true;
}
return false;
}
It doesn't seem ideal but it works for my case.
I've recently found a code that could solve my background service problem, but I don't understand one part of it. Could you tell me what should I write in !calledOtherActivity? This part is red in my code and the hint says: " cannot resolve symbol 'calledOtherActivity' "
Code
#Override
public void onPause() {
if(!isFinishing()){
if(!calledOtherActivity){
stopService(serviceRef);
}
}
}
let's understand the Situation
if( condition )
{
// if condition is true it goes here
}
else
{
// bah condition is false meaning !true
}
If the condition in the above statement is false, then the statements in the else block will always be executed.
If it is true it goes inside it like i commented
This condition only can be true or false
and since you have only one in the condition called calledOtherActivity it needs to carry true or false so its a boolean
private boolean calledOtherActivity;
by default its value is false
looking to your condition it is if(!calledOtherActivity) as i said to go inside this it needs to be true
! <--- this is NOT operator this inverts the value of a boolean
so if you pass calledOtherActivity with a false value because of this NOT operator the full output of the condition becomes true
I am trying to create a random (50/50) chance of a case A or case B happen in android and I need it to be as simple and as resource efficient as possible. I've looked through stackoverflow but all I find for random boolean is in C++?
Would appreciate if someone could give me a suggestion as to how to do this, whether with boolean or with strings/integers (since I was told that booleans is a primitive).
I tried the following
public static boolean getRandomBoolean() {
return Math.random() < 0.5; }
boolean atrg = getRandomBoolean();
if (atrg = true)
{ Toast.makeText(cxt, "TRUE", Toast.LENGTH_SHORT).show(); }
else if (atrg = false)
{ Toast.makeText(cxt, "FALSE", Toast.LENGTH_SHORT).show(); }
But in nearly every case, I tested (>20x), its TRUE?. This is likely a stupid question but is getRandomBoolean a boolean or an int/double? Sorry, I'm very new to android, as you probably guessed.
Your random generator is fine, but your toast displaying the result is not.
The problem is in the if-statement where you use a single equals sign (=) which is an assignment. The result of this assignment will be true and thus it will never show the "FALSE" toast.
Try this instead.
boolean atrg = getRandomBoolean();
if (atrg) {
Toast.makeText(cxt, "TRUE", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(cxt, "FALSE", Toast.LENGTH_SHORT).show();
}
This is not how you check boolean in if. = is the assignment operator and == is used for comparison. You should check like:
if(atrg == true)
or in case of boolean it is simply:
if(atrg)
Your statement:
if(atrg = true)
assigns atrg with true and you never get a false case.
Just use Math.random(), it will return a value between 0 and 1.. Example below:
public static boolean getRandomBoolean() {
return Math.random() < 0.5;
}
public static void main(String[] args) {
System.out.println(getRandomBoolean());
}
I have some code, but it is not working as expected. My logic doesn't seem to be faulty, so I think it is an implementation error. My code:
public boolean[] party_check(){
Date date_ET = new Date(party_dateET.getYear(), party_dateET.getMonth(), party_dateET.getDayOfMonth());///Date is deprecated,
///but easy to handle
///this is used to test the date contained in the datepicker, party_dateET. If it is before the day today, then it will not write,
///and a message is displayed
boolean[] return_array = new boolean[4];
///EditText party_titleET;
///EditText party_timeET;
///EditText party_dateET;
///EditText party_venueET;
return_array[0] = true;
if(party_titleET.getText().length() == 0){
return_array[1] = false;
return_array[0] = false;
}else{
return_array[1] = true;
}
if(date_ET.before(Calendar.getInstance().getTime()) == true){
return_array[2] = false;
return_array[0] = false;
///tests that the date entered is not invalid, ie. is in the future.
///not test for time. I could say that if time == 00:00, then don't run, or use a listener to check if it has changed,
///using a boolean value. But this would not really benefit the task much, so I haven't. It would also
///take more coding, and more complex coding.
}else{
return_array[2] = true;
}
if(party_venueET.getText().length() == 0){
return_array[3] = false;
return_array[0] = false;
}else{
return_array[3] = true;
}
return return_array;
///return_array[0] - 1st value in array - is used as toggle as to whether the party is ready or not.
///return_array[1-4] are used to indicate to the user which textbox is empty/ has a problem.
}
However it does not do what I expect it to do when I return the boolean array. This is used for testing whether the user has entered a text value into the EditText's.
However it does not work as expected. Is my logic faulty, or I have implemented it wrong? Thanks for the help!!
The hint does not get returned, when you use getText(). You can use getHint() though.
Text and Hint are different properties.
So the Text will be empty, if the hint is shown.
Let's say that the hint is a "dress" for the text (not to let it "naked"), but it's not the text itself.
I have the following code that evaluates to true in the emulator (OS 2.3.3) when "applications > settings > development > allow mock locations" is unchecked. I would expect the method to return false but it returns true.
public static boolean isMockLocationSet(Context context) {
if (Settings.Secure.getInt(context.getContentResolver(), Settings.Secure.ALLOW_MOCK_LOCATION, 0) == 0) {
return false;
}
else {
return true;
}
}
The following change returns false, as expected (BTW what is better .equals or .ContentEquals?):
public static boolean isMockLocationSet(Context context) {
if (Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ALLOW_MOCK_LOCATION).equals("0")) { //.contentEquals("0")
return false;
}
else {
return true;
}
}
I prefer the first example because it should allow for cases where a null value may exist, assigning a default of 0 and still allowing execution of the logic without failure (in fact, I suspect this case may exist but have not proved it - e.g. a manufacturer implements Android without all the these settings established (i.e. some like Allow Mock Locations would begin their life as null)...waiting until a user check's the setting before writing a 1 (or 0 when unchecked) to the table).
So what is the problem? Well, I get the feeling from bug reports that different devices handle this check differently but not having access to all device types, I am looking for recommendations on how to handle generically / the best. Also, why would the first example not work?
Well I decided to simply use the following check:
public static boolean isMockLocationSet(Context context) {
if (Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ALLOW_MOCK_LOCATION).contentEquals("1")) {
return true;
}
else {
return false;
}
}
This method, of course, deals with the null case appropriately--returning false.
I cannot say why the code in the original question does not work...maybe a bug in the SDK.