Develop Reference

Change Button Color dynamically with the Integer Value

I want to change the Button color with the Integer Value. So if my Integer Value is 1 it should be green once it goes up it should change dynamically to yellow and at the end should change to red. How can i implement this.
I tried with interpolation but i can't get the value i need its changing the color but not very precise.

Please let me know whether this is helpful.
yourButtonName.setBackgroundColor(colorIntVariable);
"colorIntVariable" is a self chosen variable name for an integer created with the rgb method:
https://developer.android.com/reference/android/graphics/Color.html#rgb(int,%20int,%20int)
int colorIntVariable = rgb(0,255,0);
Above code can be used for displaying a green object.
An example can be:
public class MainActivity extends AppCompatActivity {
Button yourButtonName;
Button plusButton;
Button minusButton;
int red;
int green;
int input = 1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
yourButtonName = findViewById(R.id.button);
plusButton = findViewById(R.id.plusbutton);
minusButton = findViewById(R.id.minusbutton);
plusButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
input = input + 10;
changeButtonColor(input);
}
});
minusButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
input = input - 10;
changeButtonColor(input);
}
});
}
public void changeButtonColor(int inputValue) {
if(inputValue <= 256) {
green = 255;
red = inputValue -1;
}
else {
green = 255 - (inputValue - 256);
red = 255;
}
int colorIntVariable = rgb(red,green,0);
yourButtonName.setBackgroundColor(colorIntVariable);
}
}

Changing the Color of the Dynamically loaded Buttons onclick

Android: I have created dynamic buttons based on my arraylist size,Lets consider 10 buttons. When a button is clicked, the color of the button will change to grey. When another one is clicked, the color of the previous button should be reset to the default color.
boolean iscolor = true;
final LinearLayout linearLayout = view.findViewById(R.id.total_count);
final LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT);
for (int j =1;j<=datalist.size()/2;j++) {
final Button btn = new Button(getContext());
final int id_ = j;
btn.setText("" + j);
btn.setTextColor(Color.WHITE);
btn.setMaxWidth(5);
btn.setId(id_);
btn.setPadding(8, 8, 8, 8);
btn.setBackgroundColor(getContext().getResources().getColor(R.color.DarkBlue));
linearLayout.addView(btn, params);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (!iscolor ) {
btn.setBackgroundColor(getResources().getColor(R.color.DarkBlue));
iscolor =true;
}
else
{
btn.setBackgroundColor(getResources().getColor(R.color.gray));
iscolor = false;
}
}});
How to restore the color of the previous clicked Button in Android.

Try this :
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
/* you need to have already stored buttons in a data structure, something like : List<Button> btns; */
for(Button b : btns){
if(b.getId() == v.getId(){ b.setBackgroundColor(getResources().getColor(R.color.gray)); } else{ b.setBackgroundColor(getResources().getColor(R.color.yourdefaultcolor)); } //no need for isColor variable
}});
linearLayout.addView(btn, params);

how do I set up a next and previous button

Hello as the title state I'm trying to setup a next and previous buttons but I'm still new at coding so this has me a little confused.
I tried to use if statements with an enum within a single button but it defaults to last if statement when the event is handled here's the code-
private enum EVENT{
pe1, pe2, pe3, pe4;
}
EVENT currentEvent = EVENT.pe1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_one_liners);
nextBtn = (Button) findViewById(R.id.nextBtn);
olText = (TextView) findViewById(R.id.olText);
nextBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (currentEvent==EVENT.pe1) {
olText.setText("PE1");
olText.startAnimation(AnimationUtils.loadAnimation(olText.this, android.R.anim.slide_in_left));
currentEvent=EVENT.pe2;
}
if (currentEvent==EVENT.pe2){
olText.setText("PE2");
olText.startAnimation(AnimationUtils.loadAnimation(olText.this, android.R.anim.slide_in_left));
currentEvent=EVENT.pe3;
}
}
});
}
I tried to use the enumerator to assign a number to each if statement so when the user hit previous it would subtract and when they hit next it would add, each number would have some text or image within its if statement but as I said it defaults to the last if statement- Any help is much appreciated.

How about this?
int eventNum = 0;
int maxEvents = XXX;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_one_liners);
prevBtn = (Button) findViewById(R.id.prevBtn);
nextBtn = (Button) findViewById(R.id.nextBtn);
olText = (TextView) findViewById(R.id.olText);
setEventData(true);
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View v) {
if(v.equals(prevBtn) && eventNum > 0) {
eventNum--;
setEventData(false);
return;
}
if(v.equals(nextBtn) && eventNum < maxEvents - 1) {
eventNum++;
setEventData(true);
return;
}
}
}
nextBtn.setOnClickListener(listener);
prevBtn.setOnClickListener(listener);
}
private void setEventData(boolean animLeft) {
olText.setText("PE" + (eventNum + 1));
if(animLeft) {
olText.startAnimation(AnimationUtils.loadAnimation(olText.this, android.R.anim.slide_in_left));
} else {
olText.startAnimation(AnimationUtils.loadAnimation(olText.this, android.R.anim.slide_in_right));
}
}

You'll want to create a class variable that keeps track of which text your TextView is showing. So in the following example, I create a list of Strings that I just store in a String array. Then I create an iterator variable which stores which String from the list I'm currently viewing in the TextView. Every time you click the previous or next button, you simply store your current state in the iterator variable so you can recall it the next time a click event comes in.
String[] labels = {"one", "two", "three", "four"};
int currentView = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onPreviousButtonClicked(View view) {
TextView textView = (TextView) findViewById(R.id.clickableLink);
currentView--; //decrement our iterator
if(currentView < 0) currentView = 0; //check to make sure we didn't go below zero
textView.setText(labels[currentView]);
}
public void onNextButtonClicked(View view) {
TextView textView = (TextView) findViewById(R.id.clickableLink);
currentView++; //increment our iterator
if(currentView > labels.length-1) currentView = labels.length-1; //check to make sure we didn't go outside the array
textView.setText(labels[currentView]);
}

How to declare intent,class,buttons in one loop?

Why this doesn't work?
public class MainActivity extends Activity {
Button[] b = null;
Intent[] intent=null;
Class[] klasa;
Typeface font;
TextView glavninaslov;
ImageView plavi,ljubicasti;
AnimationDrawable plavian,ljubicastian;
String[] naslovi;
int i=0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String[] naslovi = {"","First","Second","Third","Fourth","Fifth"};
font = Typeface.createFromAsset(getAssets(),"FatMarker.ttf");
b = new Button[]
{
( Button ) findViewById(R.id.button1),
( Button ) findViewById(R.id.button2),
( Button ) findViewById(R.id.button3),
( Button ) findViewById(R.id.button4),
( Button ) findViewById(R.id.button5),
};
for(i=1;i<6;i++)
{
klasa[i]=Class.forName(naslovi[i]);//Problem is in:"Class not found exception"
intent[i] = new Intent(MainActivity.this,klasa[i]);
b[i].setOnClickListener(new Button.OnClickListener() {
public void onClick(View v)
{
startActivity(intent[i]);
gasenje();
}
});
}
Can anyone help me...?
Does anyone had similar problems?
Please help me...
The rest of code cannot affect on program... Please help me... I would appreciate it...
I have updated my code...it starts mainactivity but when i click on some button it crush app...
Button[] b = null;
Intent[] intent=null;
Typeface font;
TextView glavninaslov;
ImageView plavi,ljubicasti;
AnimationDrawable plavian,ljubicastian;
int i=0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Class[] naslovi = {
First.class,
Second.class,
Third.class,
Fourth.class,
Fifth.class};
font = Typeface.createFromAsset(getAssets(),"FatMarker.ttf");
b = new Button[]
{
( Button ) findViewById(R.id.button1),
( Button ) findViewById(R.id.button2),
( Button ) findViewById(R.id.button3),
( Button ) findViewById(R.id.button4),
( Button ) findViewById(R.id.button5),
};
intent = new Intent[b.length];
for(i=0;i<5;i++)
{
intent[i] = new Intent(MainActivity.this,naslovi[i]);
b[i].setTag(i);
b[i].setOnClickListener(new Button.OnClickListener() {
public void onClick(View v)
{
startActivity(intent[(Integer)v.getTag()]);
gasenje();
}
});
}
This code works...thanks guys

Update:
Rather than using reflection as you are to create these classes, as kcoppock suggested you should just do this:
Class[] naslovi = {
First.class,
Second.class,
Third.class,
Fourth.class,
Fifth.class};
And then in your loop:
intent[i] = new Intent(MainActivity.this, naslovi[i]);
Original Answer:
Assuming you have a classes called First, Second, etc, you need to include the package name:
String[] naslovi = {"",
"com.package.First",
"com.package.Second",
"com.package.Third",
"com.package.Fourth",
"com.package.Fifth"};
Replace com.package with the package for each class.
Also after you fix that, I foresee that you'll then get an IndexOutOfBoundsException - remove the blank "" element from naslovi, and change your for loop to for(i=0;i<5;i++)

The problem is that i will not be retained at the current value when the OnClickListener is executed. You can use the buttons' tag value to retain the proper value.
for (int i=0; i<b.length; i++) {
//existing logic
b[i].setTag(i);
b[i].setOnClickListener(new OnClickListener() {
public void onClick(View view) {
startActivity(intent[(Integer)view.getTag()]);
}
});
}

get OnClick() from programmatically added buttons?

i have added some button in a layout:
LinearLayout row = (LinearLayout)findViewById(R.id.KeysList);
keys=db.getKeys(console);
my_button=new Button[keys.size()];
for (bt=0;bt<keys.size();bt++){
my_button[bt]=new Button(this);
my_button[bt].setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.FILL_PARENT));
my_button[bt].setText(keys.get(bt));
my_button[bt].setId(bt);
row.addView(my_button[bt]);
my_button[bt].setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (my_button[bt].getId() == ((Button) v).getId()){
Toast.makeText(getBaseContext(), keys.get(bt), 0).show();
}
}
});
}
I want to know which button is clicked and how to get text of the clicked button?And I think using bt here dose not seem to work!

This code is running. I hope it help you :)
final ArrayList<String> Keys = new ArrayList<String>();
for(int i = 0; i < 10; i ++){
Keys.add("Keys is : " + String.valueOf(i));
}
LinearLayout Row = (LinearLayout)findViewById(R.id.KeysList);
final Button[] my_button = new Button[Keys.size()];
for (int bt = 0; bt < Keys.size(); bt ++){
final int Index = bt;
my_button[Index] = new Button(this);
my_button[Index].setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT));
my_button[Index].setText(Keys.get(Index));
my_button[Index].setId(Index);
my_button[bt].setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (my_button[Index].getId() == ((Button) v).getId()){
Toast.makeText(getBaseContext(), Keys.get(Index), 0).show();
}
}
});
Row.addView(my_button[Index]);
}
ExampleProject id : Your project

You should probably use View#setTag to set some arbitrary data you'd like associate with the Button. Then you can just instantiate only one OnClickListener that then uses getTag and acts on that data in whatever way you need.

Another way is to have your Activity listen to all button clicks and then you just filter respective to the ID. You should not get the text of the button and use that at all. You should use your own type of identifier, ideally the idea should be enough. Or perhaps you use setTag as #qberticus described.

Consider This example :
public class MainActivity extends Activity implements View.OnClickListener
{
LinearLayout linearLayout;
Button [] button;
View.OnClickListener listener;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
linearLayout=(LinearLayout)findViewById(R.id.parent_lay);
String[] array={"U123","U124","U125"};
int length=array.length;
System.out.println("11111111111111111111111111");
button=new Button[length];
for(int i=0;i<length;i++)
{
button[i]=new Button(getApplicationContext());
button[i].setId(i);
button[i].setText("User" + i);
button[i].setOnClickListener(this);
linearLayout.addView(button[i]);
}
}
#Override
public void onClick(View view)
{
view.getId();
Button button=(Button)findViewById(view.getId());
button.setText("Changed");
}
}
This works fine :)