What I'm trying to do is:
If the EditText input is equal to the random number generated, then stop the loop otherwise keep on the loop and reset input text.
For some reason, I'm getting an infinite loop. I am new to programming, any help is really appreciated.
Here is the code:
public class Main extends Activity implements OnClickListener{
private TextView tvResult;
private TextView tvRandTest;
private EditText et1;
private String randonNumber;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tvResult = (TextView) findViewById(R.id.textView4);
tvRandTest = (TextView) findViewById(R.id.textView3);
et1 = (EditText) findViewById(R.id.editText1);
}//End Main
public void myClickHandler(View view)
{
if(view.getId() == R.id.button1)
{
//Generates 6 one digit Random Numbers
int randonNumber1 = (int) (0 + Math.random() * 9);
//Parse Numbers
String rd1 = Integer.toString(randonNumber1);
randonNumber = rd1;
boolean done = false;
do
{
et1.getText().toString();
if(et1.equals(randonNumber))
{
Toast.makeText(Main.this,"Equal Number", Toast.LENGTH_SHORT).show();
tvResult.setText(randonNumber);
done = true;
}//end if
else
{
Toast.makeText(Main.this,"Not Equal Number", Toast.LENGTH_SHORT).show();
et1.setText("");
}//end else
}//End While
while(!done);
}//End if
if(view.getId() == R.id.button2)
{
tvRandTest.setText(randonNumber);
}
}//End Method
#Override
public void onClick(View arg0) {
// TODO
}
}//End Class
if(et1.equals(randonNumber))
I will change it with
if(et1.equals(String.valueOf(randonNumber)))
you put directly the int value inside the equals method two things will happen:
the autboxing will create an Integer object starting from the int value
the toString() method will be called through this object.
the toString() method of Integer in android, as the doc stands:
Returns a string containing a concise, human-readable description of this object.
So you are compareing the address of the new object with the content of et1 and not with its real value. Here the reference
In this line et1.getText().toString(); you need to assign result to variable, for example String input = et1.getText().toString(); Then in next line you need to compare two strings, if(input.equals(randonNumber)) But your program can hang cause of infinity loop on UI thread. You should use TextWatcher
to handle when text in EditText was changed
Related
I have is an android class. I get some data from get extra which are displayed fine. All of the data is strings. Here is my class:
package adapter;
public class AddToCart extends Activity {
EditText quantity=null;
TextView total=null;
TextView name=null;
TextView price=null;
TextView ava=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.info);
Intent intent = getIntent();
final String itemprice = intent.getStringExtra("price");
String itemname = intent.getStringExtra("item");
final String itemava = intent.getStringExtra("ava");
int imagehandler = intent.getIntExtra("image", 0);
Log.e("image handler",imagehandler+"");
name = (TextView)findViewById(R.id.textView2);
price = (TextView)findViewById(R.id.textView4);
total = (TextView)findViewById(R.id.textView7);
ava = (TextView)findViewById(R.id.textView9);
quantity = (EditText)findViewById(R.id.editText1);
Button addtocart = (Button)findViewById(R.id.button1);
ImageView imageview=(ImageView)findViewById(R.id.imageView1);
name.setText(itemname);
price.setText(itemprice);
ava.setText(itemava);
imageview.setImageResource(imagehandler);
addtocart.setOnClickListener(new OnClickListener() {
int currentava = Integer.parseInt(itemava);
#Override
public void onClick(View v) {
try{
String checked = quantity.getText().toString();
if(checked==null) {
Toast.makeText(AddToCart.this,"please enter quantity for your item", Toast.LENGTH_LONG).show();
}
else {
int x=0;
double y=0.0;
x = Integer.parseInt(quantity.getText().toString());
y = Double.parseDouble(itemprice);
Log.e("x",x+"");
Log.e("y",y+"");
double totalprice=x*y;
total.setText(totalprice+"");
Toast.makeText(AddToCart.this,"your item added succesfully !", Toast.LENGTH_LONG).show();
}
}//view
catch(Exception e){
e.printStackTrace();
}
}
});
}
}
As you can see that quantity is edit text and when some number inserted into it multiply it by price value and show the total price in text view which works just fine when i click the button, but what I really need to do is to handle this functionality with two if statements. First if the edit text for quantity was empty and the user click the button I want a toast to be displayed to says : "please enter a value for quantity" and the other statement that if quantity larger than available to refuse the value and also toast : "please enter value less than available" It doesn't work as I have an invalid integer value exception. Please what is wrong with my code and how can i handle the previous issues?
Declare "itemava" globally and try again
Looks to me where you use ,
if(checked==null){
Toast.makeText(AddToCart.this,"please enter quantity for your item", Toast.LENGTH_LONG).show();
}
that there are 2 alternatives to this.
1.
Probably the easiest
if(checked==null || quantity.isEmpty()){
Toast.makeText(AddToCart.this,"please enter quantity for your item", Toast.LENGTH_LONG).show();
}
The addition is the || quantitiy.isEmpty()
I had tons of issues trying to solve for cases when the string was empty and this is the best way and also uses built in functions that are very easy to use.
2.
Not quite as easy but probably the better bet
Rather than checking to see if the string itself is null, it would be best to check if the editText has been changed at all, and then if it has been changed, make sure that it was changed to a non-empty string, like in 1. To do this add a textChangedListener like so:
quantity.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
//set a textChangedFlag to true
}
#Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
#Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
});
This will require a boolean flag that should always be initialized to false. Then after setting the flag to true in the onTextChanged method, you should still double check the string, just to be safe (this may be overkill, but I tend to error on the side of caution) by using a similar method as in 1.
if(textChangedFlag && !(checked == NULL || quantity.isEmpty())){
//do your math here
}
else{
Toast.makeText(AddToCart.this,"please enter a valid quantity", Toast.LENGTH_LONG).show();
}
Text can still be empty... Try something like this:
import android.text.TextUtils;
String value = quantity.getText().toString();
if (TextUtils.isEmpty(value)) {
// enter a value toast
} else if (!TextUtils.isDigitsOnly(value)) {
// must be numeric toast (notice the exclamation mark in condition)
} else {
int valueInt = Integer.parseInt(value);
// ...
}
i have 10 edittext values in activitya,i want to add them and show the result in newactivity.
my code
public class activitya extends Activity implements onclicklistener
{
private EditText editext1;
private EditText editext2;
private EditText editext3;
private EditText editext4;
private EditText editext5;
private Button calculate;
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activitya);
calculate =(Button)findviewbyid(R.id.button1);
calculate.setonclicklistener(this);
}
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.button1:
onadd();
break;
default:
break;
}
}
public void onadd()
{
Bundle bundle = new Bundle();
String value1 = editext1.getText().toString();
String value2 =editext2.getText().toString();
bundle.putString("sendvalue1",value1));
bundle.putString("sendvalue2",value2));
try{
Double Total =Double.parseDouble(value1)+Double.parseDouble(value2);}
catch(NumberFormatException e)
{
e.printstacktrace();
}
bundle.putString("totalvalue",String.valueof(Total));
Intent a = new intent(this,newactivity.class);
a.putExtras(bundle);
startactivity(a);
}
}
in newactivity :
public class newactivity extends activity{
private TextView total;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
total =(TextView)findviewbyid(R.id.text1);
onview();
}
public void onview()
{
Bundle bundle = this.getIntent().getExtras();
String param1 = bundle.getString("totalvalue");
total.setText(param1);
}
it shows the addition correctly only if i enter all the 10 values, strange
if i dont enter even one value it shows zero,
couldnt understand where the problem is
You have a try-catch and you do nothing in the catch. This is usually bad practice since you do not know when anything happens in your code.
In this case, Double.parseDouble is throwing an exception as you are trying to parse empty Strings. "" cannot be parsed to a double. "0" can.
You need to make sure that every edit text contains a valid value which can parse to a double or, test each value before trying to parse it.
To check all EditText length before you add all the values.
Like,
if(EditText1.getText.length()==0){
Toast.makeText(YourActivity.this,"All fields are mandatory ",
Toast.LENGTH_LONG).show();
}else if(EditText2.getText.length()==0){
} else if(){
..........
}else{
}
You will avoid NullPointerException
I am making an application in which i have to fetch item name and price from first activity to another and i am able to do that but in second activity i am allowing user to put quantity in numbers and whenever user will click on button a TextView to show total amount, but not able to calculate total Amount for item.
I know this is very simple task to do but i am getting error while write this line in button onClick():
txtResult=txtCost*txtQty
here i am placing second activity code,
please correct this one:-
public class SecondScreenActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.screen2);
TextView txtName = (TextView) findViewById(R.id.txtName);
TextView txtCost = (TextView) findViewById(R.id.txtCost);
EditText txtQty=(EditText)findViewById(R.id.txtQty);
Button btnClose = (Button) findViewById(R.id.btnCalculate);
TextView txtResult = (TextView) findViewById(R.id.txtResult);
Intent i = getIntent();
// Receiving the Data
String name = i.getStringExtra("name");
String cost = i.getStringExtra("cost");
// Displaying Received data
txtName.setText(name);
txtCost.setText(cost);
// Binding Click event to Button
btnClose.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
//Closing SecondScreen Activity
//finish();
txtResult=txtCost*txtQty;
}
});
}
}
You can do it by
int cost = Integer.parseInt(txtCost.getText().toString());
int qty = Integer.parseInt(txtQty.getText().toString());
int result = cost*qty;
and then set this result into txtResult
txtResult.setText(result+"");
or you can convert int to String and then apply setText
Why are to multiplying value in Textview
btnClose.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
Float f_name = new Float(name);
Float f_cost = new Float(cost);
Float f_result=f_name *f_cost ;
txtResult.setText(f_result);
}
});
}
}
txtResult=txtCost*txtQty;
These are TextView objects. You can't do maths on objects. Get the textview's values into integers and then try to multiply.
Do something like this.. depending on the type of variable you want (integer, float, double).
int a = new Integer(txtCost.getText().toString());
int b = new Integer(txtQty.getText().toString());
int c = a * b;
txtResult.setText(d);
There are 2 changes that needs to be made.
Make both txtCost and txtQty global variables.
both these variables cannot be directly multiplied. Instead do somthing like this.
double cost = Double.parseDouble(txtCost.getText().toString());
double qty = Double.parseDouble(txtQty.getText().toString());
txtResult = cost * qty ;
What's wrong here ?
Random numbers work well.
Checking the part number also works well.
But when I type a the same number that has been randomly selected is always "Toast Bad".
Code: http://pastebin.com/0pdySnW9
Sorry but i can't paste code here.
In your onClick method you are infact generating another random number.
So the number you are typing in, is NOT going to be equal to the random number, as it is NOT the one displayed on screen.
Depending on what you are trying to achieve.. remove line 32, and make random a global variable.
In your onClick you are generating a new random number with this line
int random = random();
You should make your random variable amember variable so that it can be accessed throughout your activity without changing
ex
public class MainActivity extends Activity implements OnClickListener {
private TextView display;
private Button ok;
public EditText et;
private int random; //note this is now a member variable
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ok = (Button) findViewById(R.id.button1);
ok.setOnClickListener(this);
display = (TextView) findViewById(R.id.textView1);
et = (EditText) findViewById(R.id.etNumbers);
random = random();
display.setText("Random Number:" + random); // Show the random number
}
// ************RANDOM******************************
public static int random() {
Random generator = new Random();
int x = generator.nextInt(100);
return x;
}
// ************************************************
public void onClick(View v) {
// TODO Auto-generated method stub
int numberEntered = -1;
try {
numberEntered = Integer.parseInt(et.getText().toString());
} catch (NumberFormatException nfe) {
Toast.makeText(et.getContext(), "That's not a number!",
Toast.LENGTH_LONG).show();
}
if (random == numberEntered) {
Toast.makeText(et.getContext(), "Great!", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(et.getContext(), "Bad!", Toast.LENGTH_LONG).show();
}
}
}
I have a large table with all kinds of strings and numbers, and a number of them have to be editable. The table is loaded from an object with getters and setters of course.
I want to create a general input screen with an edit text and an ok button; and use that to edit the fields. However, i can't get this to work, this is a snippet of my code:
public class InputViewController extends Activity {
private String inputType;
EditText mEdit;
private String inputString;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.inputscreen);
Bundle extras=getIntent().getExtras();
{
//get the type of input from the screen that sent us here, contained in a putextra
inputType = extras.getString("inputType");
TextView textViewInput = (TextView) findViewById(R.id.textViewInput);
textViewInput.setText(inputType);
mEdit = (EditText)findViewById(R.id.editText1);
}
//save input and return to previous screen
final Button button = (Button) findViewById(R.id.button3);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
//save input based on inputType
if(inputType.equals("Oplossing")){
inputString = mEdit.getText().toString();
ActivityViewController.activityObject.setSolution(inputString);
System.out.println(ActivityViewController.activityObject.getSolution());
}
//return to previous screen
finish();
}
});