Develop Reference

Android: java.lang.NumberFormatException: Invalid int: "1.01"

Hi in my app i am reading the values from the database thru cursor and displaying in textview
my cursor contains the value 1.01 now i wanna display 101 in my text view..doing the following
TextView tv2 = (TextView)view.findViewById(R.id.acValue);
int ach = Integer.parseInt(topcursor.getString(6));
tv2.setText(ach +"");
i am getting the float value as 1.01, now i wanna show the percentage in textview i.e, 101% .how can i do that
But iam getting numberformatexception. Any help is appreciated.

1.01 is not an integer value, that is why the conversion is failing. Also be careful with locale when you use the parse* methods

Try this
TextView tv2 = (TextView)view.findViewById(R.id.acValue);
String ach = topcursor.getString(6);
tv2.setText(ach);

There is no need to parse as it returns the string.
TextView tv2 = (TextView)view.findViewById(R.id.acValue);
String mResult = topcursor.getString(6);
tv2.setText(mResult);

Thank You all ...Did as follows it work fine..
float ach = Float.parseFloat(topcursor.getString(6));
String kj = String.valueOf(ach*100+"%");

Using replace() will do the trick
TextView tv2 = (TextView)view.findViewById(R.id.acValue);
int ach = Integer.parseInt(topcursor.getString(6).replace(".", ""));
tv2.setText(ach +"%");

Grab TextView (in a ListVIew Row ) from ContextMenu

I know to get a string of a specific TextView in a ListView, I can do this:
ReviewUser = ((TextView) rowView.findViewById(R.id.labelUser))
.getText().toString();
What if I want to get the TextView itself?
The TextView is an integer and I simply want to get the TextView and add 1 to it.

So you already specified that you know how to get the specific text from your ListView. Since you want to modify that same TextView, the rest is simple. This code is lengthier just to show the steps.
TextView textView = (TextView) rowView.findViewById(R.id.labelUser)
String text = textView.getText().toString();
int num = Integer.valueOf (text).intValue() + 1;
textView.setText (""+num);
Also, if you are working with a String ArrayAdapter and you know the index of the row you want to modify, what you can do is (assuming arrayAdapter is initialized and index is your index variable):
String text = arrayAdapter.get(index);
arrayAdapter.remove (text);
arrayAdapter.insert ((Integer.valueOf (text).intValue() + 1 ) + "", index);

Android - Getting User Input As An Integer

I'm a new Android developer. As a starting project, I'm trying to create a basic addition calculator. I have an EditText which is supposed to take the input (input is a string) and convert it to int1 when Button1 is pressed. When Button2 is pressed, it is supposed to take the input, convert it to int2, add int1 and int2 together and store the result in the int ans, and set the text of the EditText to ans. However, when I try to use Integer.parseInt(et.getText().toString()) I get an error and the app force closes. Could anyone provide me with the code to properly convert these Strings to integers? Thank you.
static int fn = 0;
static int sn = 0;
static int ans = 0;
static int pro = 0;
//"+" Button Clicked//
if(pro == 0){
fn = Integer.parseInt(entry.getText().toString());
entry.setText("");
pro++;
}else{
//MessageBox Crap//
//"=" Button Clicked//
sn = Integer.parseInt(entry.getText().toString());
ans = fn + sn;
entry.setText(ans);

Shouldn't ans be converted to a string before you set the contents of the EditText?

Android: Set a random image using setImageResource

I need a help with setting a random image using setImageResource method.
In the drawable folder, I have a jpeg file named photo0.jpg, photo1.jpg...photo99.jpg.
And the following code works:
int p = R.drawable.photo1;
image.setImageResource(p);
The above will display photo1.jpg but I want to show a random image.
I tried the following but it doesn't work.
String a = "R.drawable.photo";
int n = (int) (Math.random()*100)
String b = Integer.toString(n);
String c = a+b;
int p = Integer.parseInt(c);//checkpoint
image.setImageResource(p);
It seems like the string "R.drawable.photoXX" isn't being changed to integer at the checkpoint.
Could someone please teach me a right code?
Thank you in advance.

Strings are pretty much evil when it comes to work like this due to the overhead costs. Since Android already provides you with integer id's I would recommend storing all of them to an int array and then using a random number for the index.
The code would look something like this:
int imageArr[] = new int[NUM_IMAGES];
imageArr[1] = R.drawable.photo;
//(load your array here with the resource ids)
int n = (int)Math.random()*NUM_IMAGES;
image.setImage(imageArr[n]);
Here we have a pretty straight forward implementation and bypass all the creation and destruction that occurs with the string concats.

maybe the error is here
int n = (int) (Math.random()*100)
put % not * Like this
int n = (int) (Math.random()%100)
to get all numbers under 100

Android - get selection of text from EditText

I'm trying to implement a copy/paste function. How can I get a selection of text from an EditText?
EditText et=(EditText)findViewById(R.id.title);
blabla onclicklistener on a button:
int startSelection=et.getSelectionStart();
int endSelection=et.getSelectionEnd();
Then I'm stuck. Any ideas?

Seems like you've already done the hard part by finding what the selected area is. Now you just need to pull that substring out of the full text.
Try this:
String selectedText = et.getText().substring(startSelection, endSelection);
It's just a basic Java String operation.

You should use a special function from the Editable object:
Editable txt = et.getText();
txt.replace(int st, int en, CharSequence source)
This command replaces the part specified with (st..en) with the String (CharSequence).

you don't need to do all this, just long press on edit text it will show you all relevant options to Copy/Paste/Select etc. If you want to save the text use the method shown by mbaird

String selectedText = et.getText().toString().substring(startSelection, endSelection);
getText() returns an editable. substring needs a String. toString() connects them properly.

You can do it this way to get the selected text from EditText:
EditText editText = (EditText) findViewById(R.id.editText3);
int min = 0;
int max = editText.getText().length();
if (editText.isFocused()) {
final int selStart = editText.getSelectionStart();
final int selEnd = editText.getSelectionEnd();
min = Math.max(0, Math.min(selStart, selEnd));
max = Math.max(0, Math.max(selStart, selEnd));
}
// here is your selected text
final CharSequence selectedText = editText.getText().subSequence(min, max);
String text = selectedText.toString();