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Parsing issue android widget to int

Need help parsing, I have tried "porting" my dice roller project to Android using Android Studio, I have most of the controller values replaced with their android widget counterparts, one problem, I am not sure how to properly parse widget values to an Int. I have marked them with aligned left comments below.
modifier is an EditText
result is a TextView
I have tried many combinations and this is the most recent.
The one that worked when it was pure java was .getValue().toString().trim() but I cannot use .getValue why is this?
public void onStart()
{
super.onStart();
percentile.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick (View v)
{
{
//issue is here
int total = Nat20_core.roll10(cumulative.isChecked(),
Integer.parseInt (String.valueOf(modifier)),
Integer.parseInt(String.valueOf(result)));
//end issue
result.setText(String.valueOf(total));
}
}
});
}
I have also tried this in a previous program as
set

This is because there is no .getValue() method for EditText and TextView widget.
For EditText, you can use getText() which returns an Editable. So, you need to get the string from it using toString(). So, you will need to use:
modifier.getText().toString();
For TextView, you can use getText() which returns a CharSequence. You also need to get the string from it using toString(). So, you can use the above line too:
result.getText().toString();
Now, you need to convert the following code:
int total = Nat20_core.roll10(cumulative.isChecked(),
Integer.parseInt (String.valueOf(modifier)),
Integer.parseInt(String.valueOf(result)));
to:
int total = Nat20_core.roll10(cumulative.isChecked(),
Integer.parseInt (modifier.getText().toString()),
Integer.parseInt(result.getText().toString()));

In EditText and TextView, the "value" is "text":
Integer.parseInt(modifier.getText().toString())

Android NumberFormatException when parsing EditText

I'm writing an app that takes in an input from the AddBook class, allows it to be displayed in a List, and then allows the user to Search for their book. To this end, I'm creating a temporary EditText, binding it to the box where the user actually enters their search value, then (after ensuring that it is not empty) I compare what they've entered for the ISBN number with the ISBN numbers of each entry in the arrayList of <Book> custom objects, the list being named books.
Problem is, when I try to parse the EditText into an Int, it doesn't seem to work. I first tried using toString() on the EditText, then using Integer.parseInt() on the result of that method, but it hasn't worked out, as the conversion is seemingly unsuccessful;
All of the resources are in place and the code compiles properly, so those aren't the problems here.
EditText myEdTx = (EditText) findViewById(R.id.bookName);
if(myEdTx.getText().equals("")){Toast toast = Toast.makeText(this, "Please enter something for us to work with!", Toast.LENGTH_SHORT);
toast.show();}
else{
//resume here
for(int i=0; i<books.size(); i++)
{
Book tBook = new Book(i, null, null); tBook = books.get(i); String s=myEdTx.toString();
int tInt = Integer.parseInt(s);`

To get the string representation of an EditText's content, use:
String s = myEdTx.getText().toString();
Using toString() directly on the EditText gives you something like:
android.widget.EditText{40d31450 VFED..CL ......I. 0,0-0,0}
...which is clearly not what you want here.

You assume the user inputs a number into the text field, but that is unsafe, as you only get a string text (which theoretically can contain non-numbers as well). When I remember correctly, you can adjust a text field in android where a user only can input numbers, which should suit you more.

NumberFormatException occurs when Integer.parse() is unable to parse a String as integer, so, its better to Handle this exception.
String s = myEdTx.getText().toString();
try {
int tInt = Integer.parseInt(s);
} catch( NumberFormatException ex ) {
//do something if s is not a number, maybe defining a default value.
int tInt = 0;
}

So the current String here you are trying to parse is with white space in the line
and integer class unable to parse that white space. So use following code.
String s=myEdTx.getText().toString();
int tInt = Integer.parseInt(s.trim());

String s = myEdtx.getText().toString().trim();
int iInt = Integer.parseInt(s);

What android:inputType should I use for entering an IP Address and hostname?

I am building a small Android app where the user will enter an IP address or a hostname into an EditText widget. 90% of the time they will be entering an IP address, the rest of the time - a hostname.
So naturally, I want to make it easy for them to enter an IP address, but the ability to switch to alpha numerics for hostname entry is important.
I can't seem to find a good inputType. The numberDecimal initially seemed like a good shot, but it only allows one dot.
Ideally, I'd like to start with a standard keyboard that had the ?123 button pressed.
How do I get there?

Try using android:inputType="number", but also set android:digits="0123456789.". Works for me.

If you use inputType="phone" you gain access to a cut down keyboard containing Numbers and a Period character - this doesn't restrict the input with regards to the amount of Periods you can enter.
Please see this answer for validation while being entered.

This works perfectly keyboard with numbers and decimal by adding android:inputType="number|numberDecimal" and android:digits="0123456789."
Example
<EditText
android:id="#+id/ip_address"
android:inputType="number|numberDecimal"
android:digits="0123456789."
android:layout_width="match_parent"
android:layout_height="wrap_content"/>

You can use your own input filter for that
final EditText text = new EditText(ServerSettings.this);
InputFilter[] filters = new InputFilter[1];
filters[0] = new InputFilter() {
#Override
public CharSequence filter(CharSequence source, int start,
int end, Spanned dest, int dstart, int dend) {
if (end > start) {
String destTxt = dest.toString();
String resultingTxt = destTxt.substring(0, dstart) +
source.subSequence(start, end) +
destTxt.substring(dend);
if (!resultingTxt.matches ("^\\d{1,3}(\\." +
"(\\d{1,3}(\\.(\\d{1,3}(\\.(\\d{1,3})?)?)?)?)?)?")) {
return "";
} else {
String[] splits = resultingTxt.split("\\.");
for (int i=0; i<splits.length; i++) {
if (Integer.valueOf(splits[i]) > 255) {
return "";
}
}
}
}
return null;
}
};
text.setFilters(filters);

use this :
<EditText
android:id="#+id/txtIP"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:digits="0123456789."
/>

<EditText
android:id="#+id/ip_address"
android:inputType="number|numberDecimal"
android:digits="0123456789."
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
worked for me

I think your only option is..
EditText android:inputType="text" ... />
You could possible check the Text for 3 dots a IP address contains

I think you need to use TextWatcher for validation, register it with TextView.addTextChangedListener() method and use Pattern.DOMAIN_NAME and Pattern.IP_ADDRESS (Android 2.2+).
See:
Android: How can I validate EditText input?
Validating IP in android

You can extend the DigitsKeyListener (source) and change the filter() function (validation that will check either ip pattern or a string hostname) and getInputType() to return InputType.TYPE_CLASS_PHONE;

Maybe if you use 2 radiobutton, one shows an edittext for host, the other one shows 4 numeric edittext for IP, then, once the user submit data you concat all 4 edittext values with dots between them, something like this, edittext1.getText() + "." + edittext2.getText() + "." edittext3.getText() + "." edittext4.getText() so you can obtain a validated IP address like that but obviously it will imply more work.

Here is the code that allows you to display a soft keyboard with only numbers and a dot (but allows you to enter multiple dots).
etIpAddress.setInputType(InputType.TYPE_CLASS_NUMBER);
etIpAddress.setInputType(InputType.TYPE_NUMBER_FLAG_DECIMAL);
etIpAddress.setKeyListener(DigitsKeyListener.getInstance(false,false));
etIpAddress.setKeyListener(DigitsKeyListener.getInstance("0123456789."));

SKTs answer is working pretty well until the InputFilter passes Spannables. Spannables are tricky to handle which is described for example ins answers of this question. In this case, returning "" for invalid input will replace the whole text by an empty string. I've adapted the solution also to handle this case. Here is the code, differing the types, in Kotlin:
val ipAddressFilters = arrayOf(InputFilter { source, start, end, dest, dstart, dend ->
if (end > start) {
val toCheck = if (source is Spannable) {
source.toString()
} else {
val destString = dest.toString()
destString.substring(0, dstart) + source.subSequence(start, end) + destString.substring(dend)
}
if (!toCheck.matches("^\\d{1,3}(\\.(\\d{1,3}(\\.(\\d{1,3}(\\.(\\d{1,3})?)?)?)?)?)?".toRegex())) {
return#InputFilter if (source is Spannable) { dest } else { "" }
} else {
val splits = toCheck.split("\\.".toRegex()).toTypedArray()
for (i in splits.indices) {
if (splits[i] != "" && Integer.valueOf(splits[i]) > 255) {
return#InputFilter if (source is Spannable) { dest } else { "" }
}
}
}
}
null
})

Try using android:inputType="textUri". It works especially well when you want hostname or IP address.

Limit EditText to text (A-z) only

I want an editText that only allows text input from A to z, no numbers or other characters. I've found out I have to use InputFilter but I don't understand how this code works.
InputFilter filter = new InputFilter() {
public CharSequence filter(CharSequence source, int start, int end,
Spanned dest, int dstart, int dend) {
for (int i = start; i < end; i++) {
if (!Character.isLetterOrDigit(source.charAt(i))) {
return "";
}
}
return null;
}
};
edit.setFilters(new InputFilter[]{filter});

The code you posted adds a custom filter to the EditText field. It checks to see if the character entered is not a number or digit and then, if so, returns an empty string "". That code is here:
if (!Character.isLetterOrDigit(source.charAt(i))) {
return "";
}
For your needs, you want to change the code slightly to check if the character is NOT a letter. So, just change the call to the static Character object to use the isLetter() method. That will look like this:
if (!Character.isLetter(source.charAt(i))) {
return "";
}
Now, anything that is not a letter will return an empty string.

Haven't actually done it, but check Androids NumberKeyListener. You can find the source code for it here:
http://www.java2s.com/Open-Source/Android/android-core/platform-frameworks-base/android/text/method/NumberKeyListener.java.htm
it does exactly the opposite of what you need, but that should be a good enough starting point.

what's the best way to apply a mask to an EditText on Android?

what's the best way to mask a EditText on Android?
I Would like my EditText to behave like this decimal number input here.
Is there a easy way to do this?

You have to programmatically set an InputFilter on your EditText by setFilters.
From the documentation:
InputFilters can be attached to Editables to constrain the changes that can be made to them.
You can even change the users input, for example by adding a decimal point which is what you want if I get you correctly.

I built a decimal mask for an edit text that will auto change the edit text to the number of decimal places you want. Bascially, you listen for text changes and loss of focus.
private void formatNumber() {
sNumberToFormat = etNumberToFormat.getText().toString();
sDecimalMask = etDecimalMask.getText().toString();
boolean periodMask = false;
String delimiter = getDelimiter();
String[] decimalMask = getsDecimalMask();
if (decimalMask.length == 1) {
return;
} else {
if (delimiter.equalsIgnoreCase(",")) {
//decimal format only currently works with dot delimiters.
sDecimalMask = sDecimalMask.replace(",", ".");
}
DecimalFormat df = new DecimalFormat(sDecimalMask);
df.setRoundingMode(RoundingMode.UP);
sNumberToFormat = df.format(Float.valueOf(sNumberToFormat.replace(",", ".")));
//if (maxNumber > Float.valueOf(sNumberToFormat)) {
if (delimiter.equalsIgnoreCase(",")) {
sNumberToFormat = sNumberToFormat.replace(".", ",");
}
etNumberToFormat.setText(sNumberToFormat);
}
}
The complete demo is here.

I think you can use:
android:numeric="decimal"
on your EditText