Display decimals with a textview - android

Hi i want make so the TextView level can put out decimal but i don'ty know how to do that any one got an idea? NOw it only puts out 1 but i want it to put out 1.80. :)
public class Main extends Activity {
int counter;
EditText weight, hours;
TextView amount, level;
Button calcuate;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
counter = 0;
weight = (EditText) findViewById(R.id.weight);
hours = (EditText) findViewById(R.id.hours);
amount = (TextView) findViewById(R.id.amount);
level = (TextView) findViewById(R.id.alcohol_level);
calcuate = (Button) findViewById(R.id.calcuate);
final String widmark = getResources().getString(
R.string.widmark);
final String hundra = getResources().getString(
R.string.hundra);
final String cl = getResources().getString(
R.string.cl);
calcuate.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Integer wid, mgs;
String w = weight.getText().toString();
String h = hours.getText().toString();
wid = Integer.parseInt(w) * Integer.parseInt(widmark) / Integer.parseInt(hundra);
mgs = Integer.parseInt(cl) / Integer.parseInt(wid.toString()) / Integer.parseInt(hundra);
level.setText(mgs.toString());
}
});
}
}

Your mgs variable is a Integer object. Set it to type float to have decimal places be displayed.
float mgs = Integer.parseInt(cl) / Integer.parseInt(wid.toString()) / Integer.parseInt(hundra);
I hope this helps.

int division will only produce int's. If you want your output to be of float or double type, you must use double or float division.
Double mgs;
mgs = Double.parseDouble(cl) / Double.parseDouble(wid.toString()) / Double.parseDouble(hundra);
Note that not all variables considered in the expression need to be double's, only one of them does.
Another thing that is noteworthy here is whether or not you want two decimal places (assuming a currency here). By default, Java/Android will only spit out as many decimal places as necessary. 1.80 will display as 1.8. To alleviate this, you should use a NumberFormat (specifically, use NumberFormat.getCurrencyInstance()) so that you can specify that you want the number of decimals for your default Locale's currency.

Related

How to set LineSpacing programmatically?

i am new to Android Studio . I want to increase or decrease textView's line spacing on click. currently i am using this one and it works but i want when user click + than line spacing increased and decreased for - .
here is my code.
textView.setLineSpacing(0,1.1f);
i have tried this but not works
private int textSpace = (int) 1.0f;
private int diff = (int) 0.1f;
and than this
textSize = textSpace+diff;
textView.setLineSpacing(0,textSize);
same for minus, but its not working , please help
Here is a checked example. I hope everything is well described
// Here put ids of your views
TextView textView = findViewById(R.id.textView);
Button plusButton = findViewById(R.id.plus);
Button minusButton = findViewById(R.id.minus);
// The multiplier may be unchanged
final float multiplier = textView.getLineSpacingMultiplier();
// Set the appropriate offset
final float offset = 1f;
plusButton.setOnClickListener(view -> textView.setLineSpacing(textView.getLineSpacingExtra() + offset, multiplier));
minusButton.setOnClickListener(view -> textView.setLineSpacing(textView.getLineSpacingExtra() - offset, multiplier));
I suppose you want to achieve something like this:
private int textSize = 20;
button.setOnClickListerner {
textSize += diff;
textView.setLineSpacing(0, textSize);
}

Rounding to two decimal places in Android

Should be simple I know but I cant find an answer anywhere. I'm trying to round up to two decimal places, so if my answer is 164.9835 I'd like the answer to be displayed as 164.99. But what I have so far is rounding it to 164.98 for some reason.
Any help much appreciated.
double number1 = Double.parseDouble(num1.getText().toString());
double number2 = Double.parseDouble(num2.getText().toString());
double number3 = Double.parseDouble(num3.getText().toString());
double number4 = Double.parseDouble(num4.getText().toString());
double sum = (((number1 * number2)/1000)*0.5)*(number3 - number4);
total.setText (String.format("£%s", new java.text.DecimalFormat("##.##").format(sum)));
If you want to round up you can use this method
cantDecimal = 2;
number = 164.9835
public static double aroundUp(double number, int canDecimal) {
int cifras = (int) Math.pow(10, canDecimal);
return Math.ceil(number * cifras) / cifras;
}
return = 164.99
Extra: Ceil Method in Math.
The method ceil gives the smallest integer that is greater than or equal to the argument.

How do you fix the error: "Operator '*' cannot be applied to 'android.widget.EditText', 'double'"?

Button button = (Button) findViewById(R.id.button);
final TextView tv= (TextView) findViewById(R.id.tv);
final EditText distanceTxt=(EditText) findViewById(R.id.distanceTxt);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
float distance = Float.parseFloat(distanceTxt.getText().toString());
float dec = distanceTxt * 7.9;
float total= dec * 1;
tv.setText(Float.toString(total));
That is my code and the error is basically when in type
distanceTxt * 7.9;
It says "Operator '*' cannot be applied to 'android.widget.EditText', 'double'".
I know the error might be obvious ,but honestly I can not seem to figure it out.
Thank you in advance.
You calculate distance, but you multiply distanceTxt.
float dec = distance* 7.9;
Will work
First you will use distance instead of distanceTxt then you will use float dec = (float) (distance * 7.9)it will work.

Why I can not see the double value in a textView

Why I can not see the double value in a textView?
textView = (TextView) findViewById(R.id.textView);
double x = 5/2;
textView.setText(String.valueOf(x)); // I see this result as 2.0 and not as the 2.5
In Android TextView, you can use in that way,
Use Double.toString:
result = number1/number2
String stringdouble= Double.toString(result);
textview1.setText(stringdouble));
or you can use the NumberFormat:
Double result = number1/number2;
NumberFormat nm = NumberFormat.getNumberInstance();
textview1.setText(nm.format(result));
To force for 3 units precision:
private static DecimalFormat REAL_FORMATTER = new DecimalFormat("0.###");
textview1.setText(REAL_FORMATTER.format(result));
You are seeing 2.0 because 5/2 is integer division. Change the line to double x = 5.0/2; or similar.
See this question for more.
This should work double x = ((double) 5) /2.

Show expanded float value in Android

I have a function that simply converts units, and my goal is for the output number to be displayed in expanded form, as in showing the full number, not "3.0E7". The code is as follows:
public void convertUnits(View view)
{
EditText fromNumberEditText = (EditText)view.findViewById(R.id.fromField);
TextView toNumberEditText = (TextView)view.findViewById(R.id.toField);
String fromUnitString = selectedList[selectedLeftItem];
String toUnitString = selectedList[selectedRightItem];
float fromUnit = Float.parseFloat(fromUnitString.split(",")[2]);
float toUnit = Float.parseFloat(toUnitString.split(",")[2]);
float fromNumber = Float.parseFloat(fromNumberEditText.getText().toString());
float toNumber = (fromNumber * fromUnit) / toUnit;
toNumberEditText.setText(Float.toString(toNumber));
}
The toNumberEditText has marquee, and because of that I would like for it to show the expanded number, i.e. 30000000 not 3.0E7. Whenever the toNumber float is anything more than 7 digits it assumes the "floating e" form. Is there a way to either change the amount of digits before it does this, or remove it altogether?
Use String.format():
toNumberEditText.setText(String.format("%f", toNumber));

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