We are trying to use this array of integers in other methods. Setting the final shuffled Array to a global variable has become next to impossible. We have set other variable as global. The goal here is to have a new int [] fix array every time a button is clicked. We have been able to generate a random int [] ar but can not utilize the array in other methods. So our questions after making the random int [] ar how can we use it in the onClickBtnOne method? Code with comments below
public class MainActivity extends AppCompatActivity {
Button btn1,btn2,btn3,btn4,btn5,btn6;
String T1,T2,T3,T4,T5,T6;
int test[] = new int[7];
int count = 0;
int v1,v2,v3,v4,v5,v6;
int[] fix = {3,2,1,4,6,5};
// Trying to not use above values
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1 = findViewById(R.id.btn1);
btn2 = findViewById(R.id.btn2);
btn3 = findViewById(R.id.btn3);
btn4 = findViewById(R.id.btn4);
btn5 = findViewById(R.id.btn5);
btn6 = findViewById(R.id.btn6);
main(null);
}
// end onCeate
public static void main(String args[]) {
int [] fix = {1,2,3,4,5,6};
shuffleArray(fix);
// Want to USE this fix shuffleArray
//==================================
for (int i = 0; i < fix.length; i++) {
System.out.print(fix[i] + ",");
}
System.out.println();
}
// Implementing Fisher–Yates shuffle
static void shuffleArray(int [] ar) {
// If running on Java 6 or older, use `new Random()` on RHS here
Random rnd = ThreadLocalRandom.current();
for (int i = ar.length - 1; i > 0; i--) {
int index = rnd.nextInt(i + 1);
// Simple swap
int a = ar[index];
ar[index] = ar[i];
ar[i] = a;
}
}
public void onClickBtnOne(View view){
btn1.setBackgroundColor(getColor(R.color.color_Red));
btn1.setEnabled(false);
count = count + 1;
v1 = count;
test[v1] = count;
if(fix[0] == test[v1]){
// Need a global fix[] here
// =========================
T1 = "true";
if(T1.matches("true")){
btn1.setBackgroundColor(getColor(R.color.color_Yellow));
}
}else {
T1 = "false";
}
}
The array you are trying to use does not have an add method you need to put the values in from another variable like this ar[i] = a; So if you use this type of Array declaration List value = new ArrayList<>(); where you declared the other global variable life will be much easier. Modified code below
This will do the shuffle NOTICE value.clear() without this the List will grow each time it is initialized
public void shf(View view){
value.clear();
for (int i = 1; i <= 6; i++) {
value.add(i);
}
Collections.shuffle(value);
}
And here is your test method call value.get(index) Arrays are ZERO based
public void on1(View view){
btn1.setBackgroundColor(getColor(R.color.color_Red));
btn1.setEnabled(false);
if(value.get(0) == 1){
T1 = "true";
if(T1.matches("true")){
btn1.setBackgroundColor(getColor(R.color.color_Yellow));
}
}else {
T1 = "false";
}
}
Related
int size = mcq.size();
String arr[] = null;
int i;
{
for (i = 0; i < size; i++) {
if (op1.isPressed()) {
arr[i] = tv1.getText().toString();
// Log.e("Array",arr[i]);
} else if (op2.isPressed()) {
arr[i] = tv2.getText().toString();
//Log.e("Array",arr[i]);
} else if (op3.isPressed()) {
arr[i] = tv3.getText().toString();
// Log.e("Array",arr[i]);
} else if (op4.isPressed()) {
arr[i] = tv4.getText().toString();
//Log.e("Array",arr[i]);
}
I am trying to store the data in an array when the button is pressed,but it always shows null.And when the for loop is over I want to display my array.
here , Arrays in Java have a size so u cannot do like this. Instead of this
use list,
ArrayList<String> arr = new ArrayList<String>();
Inorder to do using String array :
String[] arr = new String[SIZEDEFNE HERE];
For ur answer :
ArrayList<String> arr = new ArrayList<String>();
int i;
{
for (i = 0; i < size; i++) {
if (op1.isPressed()) {
arr.add(tv1.getText().toString());
} else if (op2.isPressed()) {
arr.add(tv2.getText().toString());
} else if (op3.isPressed()) {
arr.add(tv3.getText().toString());
} else if (op4.isPressed()) {
arr.add(tv4.getText().toString());
}
Retrive value using
String s = arr.get(0);
This is because your string array is null. Declare it with the size as
String[] arr = new String[size];
Try Array List. use the following code in your main java
final ArrayList<String> list = new ArrayList<String>();
Button button= (Button) findViewById(R.id.buttonId);
final EditText editText = (EditText) findViewById(R.id.editTextId)
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
list.add(editText.getText().toString());
}
});
To avoid duplication in arraylist .You can use arraylist for faster then String array
ArrayList<String> list = new ArrayList<String>();
list.add("Krishna");
list.add("Krishna");
list.add("Kishan");
list.add("Krishn");
list.add("Aryan");
list.add("Harm");
System.out.println("List"+list);
HashSet hs = new HashSet();
hs.addAll(list);
list.clear();
list.addAll(hs);
i wrote a code for calculating some weights. they are integer weights.
and i need to save them in every time the button is clicked.
please help me. i cant see why the compiler gives me an error when i try to push the button for the second time. here is my complete code:
public class TrainingActivity extends Activity {
private EditText etIn1, etIn2, etDesired;
private TextView prevInput;
int W[][] = new int[2][];
int X[][] = new int[30][];
int w0=0, w1=0, w2=0, p=1, sum=0, clicks=0;
private Button nxtData;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.training_activity);
View backgroundImage = findViewById(R.id.background);
Drawable background = backgroundImage.getBackground();
background.setAlpha(40);
etIn1= (EditText) findViewById(R.id.etInput1);
etIn2 = (EditText) findViewById(R.id.etInput2);
etDesired = (EditText) findViewById(R.id.etDesired);
prevInput = (TextView) findViewById(R.id.prevInput);
nxtData = (Button) findViewById(R.id.nextData);
nxtData.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
int sum = 0;
++clicks;
int intetIn1 = Integer.parseInt(etIn1.getText().toString());
int intetIn2 = Integer.parseInt(etIn2.getText().toString());
int intetDesired = Integer.parseInt(etDesired.getText().toString());
X[clicks-1] = new int[] {intetIn1, intetIn2, 1};
prevInput.setText("Last Inputs: (" + intetIn1 + ", " + intetIn2 +
", " + intetDesired + ")");
if(clicks == 1) {
if(intetDesired == 1) {
W[0] = new int[] {intetIn1, intetIn2, 1};
W[1] = W[0];
} else if(intetDesired == (-1)){
W[0] = new int[] {-intetIn1, -intetIn2, -1};
W[1] = W[0];
}
} else if(clicks > 1) {
for(int i=0; i<3; i++){
sum = sum + W[clicks-1][i] * X[clicks-1][i];
} if(sum>0 && intetDesired==1) {
W[clicks] = W[clicks-1];
} else if(sum<0 && intetDesired==(-1)) {
W[clicks] = W[clicks-1];
} else if(sum<=0 && intetDesired==1) {
for(int i=0; i<3; i++) {
W[clicks][i] = W[clicks-1][i] + X[clicks-1][i];
}
} else if(sum>=0 && intetDesired==(-1)) {
for(int i=0; i<3; i++) {
W[clicks][i] = W[clicks-1][i] - X[clicks-1][i];
}
}
}
etIn1.setText("");
etIn2.setText("");
etDesired.setText("");
}
});
}}
and here is the exception it throws:
java.lang.ArrayIndexOutOfBoundsException: length=2; index=2
UPDATEEEEEEEE
i fixed the problem with arrayindexoutofboundexception by changing W[2][] to W[20][]. but in some clicks it gives me this error:
java.lang.NullPointerException
and it's not clear in which clicks. sometimes it's in the second click. or some times it's in fourth click. please help.
W[clicks] = W[clicks - 1];
in above line, you have get error because you have only define size of the array
int W[][] = new int[2][];
so it assigned W[0][] and W[1][] only
When click on second time variable clicks value is 2 then compiler gives ArrayIndexOutOfBoundException
EDITED.............................................................
you have got null value because of your bad logic and not proper way to build two dimensional array. Pls use debug tool to find the actual problem to implement logic and use two dimensional array like below example in java or android:
List<List<Integer>> triangle = new ArrayList<List<Integer>>();
List<Integer> row1 = new ArrayList<Integer>(1);
row1.add(2);
triangle.add(row1);
List<Integer> row2 = new ArrayList<Integer>(2);
row2.add(3);row2.add(4);
triangle.add(row2);
triangle.add(Arrays.asList(6,5,7));
triangle.add(Arrays.asList(4,1,8,3));
System.out.println("Size = "+ triangle.size());
for (int i=0; i<triangle.size();i++)
System.out.println(triangle.get(i));
I have an array of buttons which contains two elements.
I'd like to create a string from the text of the buttons.
The thing i am struggling with is the if statement. Basically, it is never firing the toast. Why?
String word2 = "ok";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button buttons[] = new Button[2];
buttons[0] = (Button) findViewById(R.id.btn);
buttons[1] = (Button) findViewById(R.id.btn2);
buttons[0].setText("o");
buttons[1].setText("k");
buttons[0].setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String word = "";
for (int i = 0; i < 2; i++) {
word += buttons[i].getText().toString();
}
if (word == word2) {
Toast.makeText(getApplicationContext(), "Good",
Toast.LENGTH_LONG).show();
}
}
});
}
Change this:
if (word == word2) {
with this:
if(word.equals(word2)) {
You can't compare String with ==
Write Better Questions (basically questions)
Compare string with .equals() not ==.
Just use if(word.equals(word2) {
Why? The first one is content comparision, but the second one i just
a reference comparision so:
String a = new String("x");
String b = new String("x");
if(a==b){
System.out.println("It wont work");
}else if(a.equals(b)){
System.out.println("It will");
}
Dont ever use new String(), it was just for proof
I must write it.
Change line
for (int i = 0; i < 2; i++) {
into
for (int i = 0; i < buttons.length; i++) {
So your application will be easier to change
I visit so many solutions regarding this issue but can't catch it clearly .When ever I run the project first time it works perfectly but when I run it second time then it fire this error in logCat
The specified child already has a parent. You must call removeView() on the child's parent first
where is the error in that code segment ?where should I change in code. any suggestion is acceptable .Thanks in advance ..
Main.java
public class MainActivity extends Activity {
List<PieDetailsItem> piedata = new ArrayList<PieDetailsItem>(0);
EditText edt3;
Button btnChart;
public String s15;
public String[] strArray;
public ImageView mImageView ;
public LinearLayout finalLayout ;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
finalLayout = (LinearLayout) findViewById(R.id.pie_container);
mImageView = new ImageView(this);
edt3 = (EditText) this.findViewById(R.id.editText1);
btnChart = (Button) findViewById(R.id.button1);
btnChart.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
/*if(mImageView != null) {
finalLayout.removeView(mImageView);
}
else {*/
s15 = edt3.getText().toString();
/*System.out.println("value 1 is --->"+s10);
System.out.println("value 2 is --->"+s12);*/
System.out.println("value 3 is --->"+s15);
String domain = s15;
strArray = domain.split("\\,");
for (String str : strArray) {
System.out.println(str);
}
// }
openChart();
}
});
}
private void openChart(){
Integer[] items = new Integer[strArray.length];
//double[] distribution = new double[strArray.length];
for (int i = 0; i < items.length; i++) {
items[i] = Integer.parseInt(strArray[i]);
System.out.println("xxxxxx"+items[i]);
}
PieDetailsItem item;
int maxCount = 0;
int itemCount = 0;
// int items[] = { 20, 40, 10, 15, 5 };
int colors[] = { -6777216, -16776961, -16711681, -12303292, -7829368 };
// String itemslabel[] = { " vauesr ur 100", " vauesr ur 200",
// " vauesr ur 300", " vauesr ur 400", " vauesr ur 500" };
for (int i = 0; i < items.length; i++) {
itemCount = items[i];
item = new PieDetailsItem();
item.count = itemCount;
// item.label = itemslabel[i];
item.color = colors[i];
piedata.add(item);
maxCount = maxCount + itemCount;
}
int size = 200;
int BgColor = 0xffa11b1;
Bitmap mBaggroundImage = Bitmap.createBitmap(size, size,
Bitmap.Config.ARGB_8888);
View_PieChart piechart = new View_PieChart(this);
piechart.setLayoutParams(new LayoutParams(size, size));
piechart.setGeometry(size, size, 2, 2, 2, 2, 2130837504);
piechart.setSkinparams(BgColor);
piechart.setData(piedata, maxCount);
piechart.invalidate();
piechart.draw(new Canvas(mBaggroundImage));
piechart = null;
//ImageView mImageView = new ImageView(this);
mImageView.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
mImageView.setBackgroundColor(BgColor);
mImageView.setImageBitmap(mBaggroundImage);
//LinearLayout finalLayout = (LinearLayout) findViewById(R.id.pie_container);
finalLayout.addView(mImageView);
}
}
You're adding mImageView to the layout multiple times. A view can only be part of 1 ViewGroup. You need to either add it only once, or create a second ImageView if you really want 2 of them in the layout.
i wanted to make an application in which i have to randomaly generate images but in order....
like :- APPLE.... i want to generate it as A_PP_E....
but i also want them uniqualy every time
final int[] imageViews = {
R.id.imageView2, R.id.imageView10, R.id.imageView3,
R.id.imageView4, R.id.imageView5, R.id.imageView6, R.id.imageView8 };
int[] photos={R.drawable.aa, R.drawable.pp
,R.drawable.ee,
R.drawable.pp_blue,R.drawable.ll};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// for randomizing the view
Random rng = new Random();
List<Integer> generated = new ArrayList<Integer>();
for (int i = 0; i < 5; i++)
{
while(true)
{
Integer next = rng.nextInt(5) ;
if (!generated.contains(next))
{
generated.add(next);
ImageView iv = (ImageView)findViewById(imageViews[i]);
iv.setImageResource(photos[next]);
break;
}
}
}
Step 1): put the images in the array in correct order as follows:
int[] photos={R.drawable.aa, R.drawable.pp, R.drawable.pp_blue, R.drawable.ll, R.drawable.ee}; // correct order APPLE
Step 2): Update your code as below:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Random rng = new Random();
List<Integer> generated = new ArrayList<Integer>();
// select `n` places which will be "BLANK"
int n = 2; // example `n=2`
for (int i = 0; i < n; i++)
{
while(true)
{
Integer next = rng.nextInt(5) ;
if (!generated.contains(next))
{
generated.add(next);
break;
}
}
}
// now `generated` has `n` random positions
// set these `n` positions as "BLANK" rest as "FILLED"
for (int i = 0; i < 5; i++)
{
ImageView iv = (ImageView)findViewById(imageViews[i]);
if(generated.contains(i)) {
// this was a random selected position
// set it blank or empty
iv.setImageBitmap(null);
}
else {
// set this image as the correct alphabet
iv.setImageResource(photos[i]);
}
}
}
i m doing this for getting blank images in another image view array....and its giving correct output
int n = 2; // example `n=2`
for (int i = 0; i < n; i++)
{
while(true)
{
Integer next = rng.nextInt(5) ;
Log.i("test","value:-"+next);
if (!generated.contains(next))
{
generated.add(next);
break;
}
}
}
for (int i1 = 0; i1 < 2; i1++)
{
ImageView ne = (ImageView)findViewById(nextimages[i1]);
ne.setImageResource(photos[generated.get(i1)]);Log.i("test","value:-"+photos[generated.get(i1)]);
}