Develop Reference

Disable Action listener for a while

I am newbie on Android Studio. I have a question.
I am making a match cards application.
After a failed match cards flipping back after 0,5 sec. But while this time, you can still check other cards. I want to disable that. I'm extends Button to a class. I'm posting both of this scripts. Thanks for your helps.
This is my Card Class.
public class kart extends Button {
boolean acikMi = false;
boolean cevrilebilir = true;
int arkaPlanID;
int onPlanID=0;
Drawable on;
Drawable d;
public kart(Context context, int id) {
super(context);
setId(id);
arkaPlanID = R.drawable.arka1;
if(id%8==1)
onPlanID = R.drawable.c1;
if(id%8==2)
onPlanID = R.drawable.c2;
if(id%8==3)
onPlanID = R.drawable.c3;
if(id%8==4)
onPlanID = R.drawable.c4;
if(id%8==5)
onPlanID = R.drawable.c5;
if(id%8==6)
onPlanID = R.drawable.c6;
if(id%8==7)
onPlanID = R.drawable.c7;
if(id%8==0)
onPlanID = R.drawable.c8;
d = AppCompatDrawableManager.get().getDrawable(context,arkaPlanID);
on = AppCompatDrawableManager.get().getDrawable(context, onPlanID);
setBackground(d);
}
public void cevir(){
if (cevrilebilir){
if(!acikMi){
setBackground(on);
acikMi = true;
}
else{
setBackground(d);
acikMi=false;
}
}
}
And this is my Java code.
public class GameScreen extends AppCompatActivity {
int sonKart = 0;
int skor = 0;
int hamle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_game_screen);
Intent i = getIntent();
final String s = i.getStringExtra("ad");
TextView tv = (TextView) findViewById(R.id.textView);
tv.setText(s);
GridLayout gr = (GridLayout) findViewById(R.id.grid);
kart kartlar[] = new kart[16];
for (int j = 1; j <= 16; j++) {
kartlar[j - 1] = new kart(this, j);
kartlar[j-1].setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
hamle++;
final kart k = (kart)v;
k.cevir();
if (sonKart >0){
final kart k2 = (kart) findViewById(sonKart);
if (k2.onPlanID==k.onPlanID&&k2.getId()!=k.getId()){
k2.cevrilebilir=false;
k.cevrilebilir=false;
sonKart =0;
skor++;
TextView tv = (TextView) findViewById(R.id.textView3);
TextView tv2 = (TextView) findViewById(R.id.textView5);
tv.setText("Score: "+skor);
tv2.setText("Total moves: "+hamle);
if (skor==8){
Intent i = new Intent(GameScreen.this,scoreboard.class);
i.putExtra("ham",hamle);
i.putExtra("isim",s);
startActivity(i);
//oyun bitti
}
}
else{
Handler h = new Handler();
h.postDelayed(new Runnable() {
#Override
public void run() {
k2.cevir();
k.cevir();
}
},500);
sonKart =0;
TextView tv2 = (TextView) findViewById(R.id.textView5);
tv2.setText("Total moves: "+hamle);
}
}
else{
sonKart = k.getId();
}
}
});
}
for (int j=0;j<16;j++){
int rg =(int) (Math.random()*16);
kart k = kartlar[rg];
kartlar[rg] = kartlar [j];
kartlar[j] = k;
}
for (int j = 0; j < 16; j++)
gr.addView(kartlar[j]);
}
}

to disable click on button
button.setEnabled(false);

Where am I going wrong in retrieving the values?

This is my code for a button. Whenever i click this the app shuts down!I am unable to understand why it's happening?
In my code, I am trying to check if values from dynamically created EditText field has been stored on my variable array values[] and bValues[];
I looked for many answers here on how to retrieve value from dynamic edittext fields. And I came up with this from my understanding.
Can anyone tell me where am I going wrong? And a corrected demo code will be of help!
public class MainActivity extends AppCompatActivity {
private static int a;
private static EditText ainput;
private static Button btn, set;
TextView equal_sign;
private static TableLayout tableLayout;
private static LinearLayout bMatrix;
List<EditText> allEds = new ArrayList<EditText>(a*a);
double[] values = new double[(allEds.size())];
List<EditText> bMatrixValues = new ArrayList<EditText>(a);
double[] bValues = new double[bMatrixValues.size()];
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ainput = (EditText) findViewById(R.id.a);
btn = (Button) findViewById(R.id.btn);
set = (Button)findViewById(R.id.set);
tableLayout = (TableLayout) findViewById(R.id.table1);
equal_sign = (TextView) findViewById(R.id.equal_sign);
bMatrix = (LinearLayout) findViewById(R.id.bMatrix);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
a = Integer.parseInt(ainput.getText().toString());
tableLayout.removeAllViews();
createMatrix();
}
});
set.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
for (int i = 0; i < allEds.size(); i++){
values[i] = Double.parseDouble(allEds.get(i).getText().toString());
}
for (int j = 0 ; j < bMatrixValues.size(); j++){
bValues[j] = Double.parseDouble(bMatrixValues.get(j).getText().toString());
}
if (allEds.size() > 0 && bMatrixValues.size() > 0){
Toast.makeText(MainActivity.this, "Main Matrix Values inserted!", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(MainActivity.this, "Insertion failed!", Toast.LENGTH_SHORT).show();
}
}
});
}
private void createMatrix() {
int p = 1;
for (int i = 0; i < a; i++) {
TableRow row = new TableRow(this);
TableRow.LayoutParams lp = new
TableRow.LayoutParams(TableRow.LayoutParams.WRAP_CONTENT,
TableRow.LayoutParams.WRAP_CONTENT);
lp.gravity = Gravity.CENTER;
row.setLayoutParams(lp);
EditText magicField;
for (int j = 0; j < a; j++) {
magicField = new EditText(MainActivity.this);
allEds.add(magicField);
magicField.setId((p));
magicField.setHint("et-" + (Integer.toString(p)));
magicField.setGravity(Gravity.CENTER);
magicField.setWidth(100);
row.addView(magicField, j);
p++;
}
tableLayout.addView(row, i);
}
bMatrix.removeAllViews();
equal_sign.setText("=");
equal_sign.setTextSize(30);
createBMatrix();
}
private void createBMatrix() {
int id = (a * a) + 1;
for (int s = 0; s < a; s++) {
final EditText b = new EditText(this);
bMatrixValues.add(b);
b.setId(id);
b.setHint("b-" + (Integer.toString(s + 1)));
b.setGravity(Gravity.CENTER);
b.setWidth(100);
bMatrix.addView(b);
id++;
}
}
}
And this is the output screen!
Matrix style edit text field gets created nicely. But when i give values to those fields and click on set value button app shuts down..

Equal function is not working in my java code

I have 2 textviews, 1 editbox and 1 button in my xml.
In my code, this line is not working:
if(c.equals(str)){
Toast.makeText(GameActivity.this, "Alright",Toast.LENGTH_LONG).show();
}
But next line (else statement) is working and In both cases (if & else statement) it shows else function toast ("Wrong").
Here is my code:
public class GameActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.game);
Button b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
TextView tv = (TextView) findViewById(R.id.textView1);
TextView tv2 = (TextView) findViewById(R.id.textView2);
Random r = new Random();
int i = r.nextInt(10 - 2) + 2;
tv.setText(i +"");
Random r1 = new Random();
int j = r1.nextInt((9 - 2) + 1) + 2;
tv2.setText(j +"");
int a = Integer.parseInt(tv.getText().toString());
int b = Integer.parseInt(tv2.getText().toString());
int result = a*b;
String str = String.valueOf(result);
EditText txt4 = (EditText) findViewById(R.id.editText1);
String c = txt4.getText().toString();
if(TextUtils.isEmpty(txt4.getText().toString())) {
txt4.setError("Please enter your answer");
return;
}
if(c.equals(str)){
Toast.makeText(GameActivity.this, "Alright",Toast.LENGTH_LONG).show();
}
else{
Toast.makeText(GameActivity.this, "wrong",Toast.LENGTH_LONG).show();
}
txt4.setText("");
}
});
}

Try this,
I got result
public class Test extends AppCompatActivity {
Button b1;
TextView t1,t2;
EditText e1;
int a,b;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
b1 = (Button) findViewById(R.id.button2);
t1=(TextView) findViewById(R.id.textView4);
t2=(TextView) findViewById(R.id.textView5);
e1=(EditText) findViewById(R.id.editText);
Random r = new Random();
int i = r.nextInt(10 - 2) + 2;
t1.setText(i +"");
Random r1 = new Random();
int j = r1.nextInt((9 - 2) + 1) + 2;
t2.setText(j +"");
a = Integer.parseInt(t1.getText().toString());
b = Integer.parseInt(t2.getText().toString());
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
int result = a*b;
String str = String.valueOf(result);
String c = e1.getText().toString();
if(TextUtils.isEmpty(c)) {
e1.setError("Please enter your answer");
return;
}
if(c.equals(str)){
Toast.makeText(Test.this, "Alright",Toast.LENGTH_LONG).show();
}
else{
Toast.makeText(Test.this, "wrong",Toast.LENGTH_LONG).show();
}
e1.setText("");
}
});
}}

Instead of
String str = String.valueOf(result);
you should use
String str = Integer.toString(result);

switch statement only incrementing once

I am creating a coffee ordering app for school. My intent for the code below is to increment or decrement the coffee integer based on whether the subtractCoffeeButton or addCoffeeButton is clicked. coffeeTV is used to show the user the number of coffee's queued to be ordered. subtotal and subtotalTV are used to hold the price and display it to the user.
As it is, the subtractCoffee and addCoffee buttons work to increment coffee and coffeeTV from 0 to 1 and vise-versa, subtotal and subtotalTV also work for displaying 0.00 and 2.5, but it won't increment any further than that. Further button clicks result in nothing happening when it is expected to increment coffee to 2,3,4,etc. and subtotal to 5.00,7.50,10.00,etc.
Code:
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_relative);
Button subtractCoffee = (Button) findViewById(R.id.subtractCoffeeButton);
subtractCoffee.setOnClickListener(this);
Button addCoffee = (Button) findViewById(R.id.addCoffeeButton);
addCoffee.setOnClickListener(this);
}
#Override
public void onClick(View v) {
double subtotal = 0.00;
int coffee = 0;
double coffeePrice = 2.50;
TextView coffeeTV = (TextView) findViewById(R.id.tvCoffeeOrder);
String coffeeString = coffeeTV.getText().toString();
int coffeeTracker = Integer.parseInt(coffeeString);
TextView subTotalTV = (TextView) findViewById(R.id.tvSubtotalCost);
switch (v.getId()) {
case R.id.subtractCoffeeButton:
if (coffeeTracker == 0) {
break;
} else if (coffeeTracker == 1) {
coffee = 0;
coffeeTracker = 0;
coffeeTV.setText(Integer.toString(coffee));
break;
} else {
coffee = coffee - 1;
coffeeTV.setText(Integer.toString(coffee));
subtotal = subtotal - coffeePrice;
subTotalTV.setText(Double.toString(subtotal));
}
break;
case R.id.addCoffeeButton:
coffee += 1;
coffeeTracker+=1;
coffeeTV.setText(Integer.toString(coffee));
subtotal = subtotal + coffeePrice;
subTotalTV.setText(Double.toString(subtotal));
break;
}
}

#Override
public void onClick(View v) {
double subtotal = 0.00;
int coffee = 0;
double coffeePrice = 2.50;
These variables have to be outside the onClick method.
Everytime you call onClick they get initiated again with 0.

because
double subtotal = 0.00;
int coffee = 0;
double coffeePrice = 2.50;
are in the local scope of your method. Declare as member variable and their value will persist as long as the current Activity is not destroyed

The problem is that you have
double subtotal = 0.00;
int coffee = 0;
at the beginning of your onClick() function. Thus, every time you click a button, you reset the number to 0 and then increment it to 1.
Besides, I'd recommend you to define separate OnClickListener instead of a global one. Something like:
public class MainActivity extends AppCompatActivity {
AppWidgetManager appWidgetManager;
SharedPreferences preferences;
SharedPreferences.Editor editor;
InputMethodManager inputMethodManager;
EditText mainEditText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Fabric.with(this, new Crashlytics());
setContentView(R.layout.activity_main);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
ActivityManager.TaskDescription taskDescription =
new ActivityManager.TaskDescription(null, null, getResources().getColor(R.color.primaryDark));
setTaskDescription(taskDescription);
getWindow().setNavigationBarColor(getResources().getColor(R.color.primary));
}
appWidgetManager = AppWidgetManager.getInstance(this);
inputMethodManager = (InputMethodManager) getSystemService(INPUT_METHOD_SERVICE);
preferences = PreferenceManager.getDefaultSharedPreferences(this);
editor = preferences.edit();
String savedText = preferences.getString("mainText", "");
mainEditText = (EditText) findViewById(R.id.mainEditText);
mainEditText.setMovementMethod(new ScrollAndSelectMovingMethod());
mainEditText.getText().append(savedText);
Selection.setSelection(mainEditText.getText(), savedText.length());
mainEditText.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
inputMethodManager.showSoftInput(mainEditText, InputMethodManager.SHOW_IMPLICIT);
}
});
mainEditText.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
#Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
onEditTextTextChanged(charSequence.toString());
}
#Override
public void afterTextChanged(Editable editable) {
}
});
}
#Override
public void onBackPressed() {
finish();
}
private void onEditTextTextChanged(String text) {
saveText(text);
updateWidget();
}
private void saveText(String text) {
editor.putString("mainText", text);
editor.commit();
}
private void updateWidget() {
int[] ids = appWidgetManager.getAppWidgetIds(new ComponentName(this, Widget.class));
for (int id : ids)
Widget.updateAppWidget(appWidgetManager, id);
}
}

As already said subtotal, coffe and coffePrice need to be outside of the onClick function. Also coffeTracker should always be the same as coffe as far as I can see, so you dont need the variable
This should be your code:
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
double subtotal = 0.00;
int coffee = 0;
double coffeePrice = 2.50;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_relative);
Button subtractCoffee = (Button) findViewById(R.id.subtractCoffeeButton);
subtractCoffee.setOnClickListener(this);
Button addCoffee = (Button) findViewById(R.id.addCoffeeButton);
addCoffee.setOnClickListener(this);
}
#Override
public void onClick(View v) {
TextView coffeeTV = (TextView) findViewById(R.id.tvCoffeeOrder);
TextView subTotalTV = (TextView) findViewById(R.id.tvSubtotalCost);
switch (v.getId()) {
case R.id.subtractCoffeeButton:
if (coffee == 0) {
break;
} else if (coffee == 1) {
coffee = 0;
coffeeTV.setText(Integer.toString(coffee));
break;
} else {
coffee = coffee - 1;
coffeeTV.setText(Integer.toString(coffee));
subtotal = subtotal - coffeePrice;
subTotalTV.setText(Double.toString(subtotal));
}
break;
case R.id.addCoffeeButton:
coffee += 1;
coffeeTV.setText(Integer.toString(coffee));
subtotal = subtotal + coffeePrice;
subTotalTV.setText(Double.toString(subtotal));
break;
}
}

Either you go with the other answers approach (field variables) or you read and parse the amounts on each onClick(). In code it would look something like:
static final double COFFEE_PRICE = 2.50;
#Override
public void onClick(View v) {
TextView coffeeTV = (TextView) findViewById(R.id.tvCoffeeOrder);
String coffeeString = coffeeTV.getText().toString();
int coffee = Integer.parseInt(coffeeString);
TextView subtotalTV = (TextView) findViewById(R.id.tvSubtotalCost);
String subtotalString = subtotalTV.getText().toString();
double subtotal = Double.parseDouble(subtotalString);
switch (v.getId()) {
case R.id.subtractCoffeeButton:
if (coffee == 0) {
break;
}
coffee--;
subtotal -= COFFEE_PRICE;
coffeeTV.setText(Integer.toString(coffee));
subtotalTV.setText(Double.toString(subtotal));
break;
case R.id.addCoffeeButton:
coffee++;
subtotal += COFFEE_PRICE;
coffeeTV.setText(Integer.toString(coffee));
subtotalTV.setText(Double.toString(subtotal));
break;
}
}

why not display two picture in text?

When I type S in text1 a corresponding picture appears in text2 however when I type G in text1 a corresponding picture is shown in text2, but the previous picture of S is shown as a letter instead of a picture. Why is that? Why can't it display two pictures? What's wrong?
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText te1 = (EditText)findViewById(R.id.t1);
final EditText te2 = (EditText)findViewById(R.id.t2);
final Button v = (Button)findViewById(R.id.b1);
v.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
//imva.setImageResource(R.id.b1);
te2.setText(" ");
String t= te1.getText().toString();
char [] aa = t.toString().toCharArray();
for (int i = 0 ; i < aa.length ; i++)
{
if (aa[i] == 's')
{
SpannableStringBuilder builder = new SpannableStringBuilder(te1.getText());
do {
ImageSpan imageSpan = new ImageSpan(getBaseContext(),R.drawable.a1);
int pos = builder.toString().indexOf("s");
builder.replace(pos, pos + 1, "$");
builder.setSpan(imageSpan, pos, pos + 1,Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
} while (builder.toString().indexOf("s") > -1);
te2.setText(builder);
}
if (aa[i] == 'g')
{
SpannableStringBuilder builder = new SpannableStringBuilder(te1.getText());
do {
ImageSpan imageSpan = new ImageSpan(getBaseContext(),R.drawable.a2);
int pos = builder.toString().indexOf("g");
builder.replace(pos, pos+ 1, "$");
builder.setSpan(imageSpan, pos, pos + 1,Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
} while (builder.toString().indexOf("g") > -1);
te2.setText(builder);
}
}