Develop Reference

Android Studio programmatically check a Checkbox and call its OnCheckedChange

Can I programmatically check a checkbox and make it call whatever it is coded to do once checked or unchecked?
For example, if I have a checkbox like this
checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked) {
Toast.makeText(getContext(), "You checked the checkbox!", Toast.LENGTH_SHORT).show();
}
else {
Toast.makeText(getContext(), "You unchecked the checkbox!", Toast.LENGTH_SHORT).show();
}
}
});
And then would've called
checkBox.setChecked(true);
my checkbox would appear checked but it wouldnt make the toast.

You can do any of the following
1. Create the listener object separate and call it manually when you call setChecked
2. Extract the method for implementation of onCheckedChanged and call it manually on your change.

As the name suggest setOnCheckedChangeListener, it only calls your callback if the checkbox value actually changes.
So if it's already checked (true), and then you call checkbox.setChecked(true), the value hasn't changed, so your callback won't be called.
Try to do checkbox.setChecked(false), and it should be working correctly.
That's my best guess, without seeing the rest of your code / xml.

Android widgets' click or touch events are not simulated. you can change states of of widgets like disabling ,enabling ,checked or unchecked programmatically but todo any task when state changes , you have to change their states manually by touching on that widget.

checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
Toast.makeText(getContext(), "You checked the checkbox!", Toast.LENGTH_SHORT).show();
}
} else {
Toast.makeText(getContext(), "You unchecked the checkbox!", Toast.LENGTH_SHORT).show();
}
}
});
Just Cheked it. it will work for me.

if you add checkboxes in LinearLayout (let's call it checkLayout) like this :
val widget = AppCompatCheckBox(checkLayout.context)
val params = LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.WRAP_CONTENT
)
widget.tag = "something you can specify later"
checkLayout.addView(widget)
the code for get the selected checkbox is like this:
checkLayout.children.forEach { cb ->
if(cb is AppCompatCheckBox && cb.isChecked){
// here you have your checkbox and by tag maybe you can do whatever you want
}
}
and for dynamic added RadioButton you can add them in RadioGroup (let's call it radioLayout) and get the selected like :
val rb: AppCompatRadioButton? = radioLayout.findViewById(radioLayout.checkedRadioButtonId)
if(rb.tag == "something"){
//your code here
}

How to find out how to change the text in the checkbox when checked?

I'm new to Android. How to find out how to change the text in the checkbox when checked?
For example I have a check box that is not checked and beside it, it says "I do not accept terms" and I want to change that to "I do accept terms" when the check box is checked.

Try this code:
checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
checkBox.setText("I do accept terms");
} else {
checkBox.setText("I do not accept terms");
}
}
});

onCheckedChanged does not seem to work

I have a checkbox. It is set to true or false depending on if a task is done or not (its a manual change). When the task is done I want the textview label to change frmo not done to done and vice versa. So I have the following code. When they click the checkbox the onCheckedChanged method does get fired off. It chooses sets the string depending on if it is true or false correctly. But then it just exits. I get no error in the logs or on the screen but when I step through the program after it sets the string in the onCheckedChanged method it just exits the getView method completely. I cant understand what is going wrong. Theres a small problem in the first couple lines that the logic for setting if the box is true or false is not entirely correct but thats fine I can fix that no problem. I just cant understand why I cant update the label after clickign the checkbox. Any help would be great.
final CheckBox statusView = (CheckBox)convertView.findViewById(R.id.statusCheckBox);
//statusView.setChecked(true);
if(toDoItem.getStatus().toString().compareTo(ToDoItem.Status.DONE.toString()) == 0)
statusView.setChecked(true);
else
statusView.setChecked(false);
// TODO - Must also set up an OnCheckedChangeListener,
// which is called when the user toggles the status checkbox
statusView
.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
Log.i(TAG,"Entered onCheckedChanged()");
if(isChecked)
statusLabelValue = "Done";
else
statusLabelValue = "Not Done";
}
});
TextView statusLabel = (TextView)convertView.findViewById(R.id.StatusLabel);
statusLabel.setText(statusLabelValue);

You will have to change the textview's text in the listener:
statusView
.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
Log.i(TAG,"Entered onCheckedChanged()");
if(isChecked)
statusLabelValue = "Done";
else
statusLabelValue = "Not Done";
((TextView)(convertView.findViewById(R.id.StatusLabel))).setText(statusLabelValue);
}
});

How to unmask a editText intput type using a CheckBox

I need to use a checkbox to add a show password feature in my android app. is there a particular way i could do this. I saw there is a method that can be used called SetTransformationMethod or something.
Can anyone help me with this please thanks

Use an EditText to enter password. And a CheckBox to show password or not.
When it checked, it show password. But when it not checked, it does show stars.
this code should work for you:
checkbox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked) {
password.setInputType(InputType.TYPE_TEXT_VARIATION_PASSWORD);
} else {
password.setInputType(129);
}
}
});
129 is the input type set when setting android:inputType="textPassword"
Hope this helps you.

Android disable button when checkbox not checked

I have a multiple checkbox and a button. What should I do to disable the button if none of the checkbox is check and enable the button if it's checked?

Try with this,
Button mButton=(Button)findViewById( R.id.button01);
CheckBox mCheckBox= ( CheckBox ) findViewById( R.id.checkbox01);
mCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener()
{
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
{
if ( isChecked )
{
mButton.setEnabled(true);
}else{
mButton.setEnabled(false);
}
}
});

When you enter in that view make the button disabled (in your XML), and whenever user hit any of the check-boxes manage one global variable e.g if the global count is > 1 then make the button enable in that activity.
Manage the global variable in a way that if user is turning on the check box then increment it and if he is turning off the checkbox decrease the counter.
I hope you got the concept.
Basically it is all about managing the count how many checkboxes are turned on; if more then one is turned on make the button enabled else make it disabled.

Instead of enabling and disabling the button you can use setVisibility() method for button.
In the following manner.
Button btn =(Button)findViewById( R.id.mybutton);
CheckBox checkBox= ( CheckBox ) findViewById( R.id.checkbox01);
mCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener()
{
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
{
if ( isChecked )
{
btn.setVisibility(VISIBLE);
}
else{
btn.setVisibility(GONE);
}
}
});
By using this method you can set the visibility of your view.Your button will be visible only if checkBox is cheaked otherwise your button will not be visible.Let me know it works or not for you.

Use this:
myButton.setEnabled(false);
See this question for more details.

you can disable button by using below code.
mBtn.setEnabled(false);
and can enable it later by using below code
mBtn.setEnabled(true);

mCheckbox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
mButton.setEnabled(isChecked);
}
});
as simple as that :)

try this
termsAndConditionsCheckBox.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
if (termsAndConditionsCheckBox.isChecked() && privacyPolicyCheckBox.isChecked()){
agreebutton.setEnabled(true);
agreebutton.setTextColor(getResources().getColor(android.R.color.white));
agreebutton.setBackgroundColor(getResources().getColor(android.R.color.holo_blue_light));
}
else {
agreebutton.setEnabled(false);
agreebutton.setTextColor(getResources().getColor(android.R.color.white));
agreebutton.setBackgroundColor(getResources().getColor(android.R.color.darker_gray));
}
}
});
privacyPolicyCheckBox.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
if (termsAndConditionsCheckBox.isChecked() && privacyPolicyCheckBox.isChecked()){
agreebutton.setEnabled(true);
agreebutton.setTextColor(getResources().getColor(android.R.color.white));
agreebutton.setBackgroundColor(getResources().getColor(android.R.color.holo_blue_light));
}
else {
agreebutton.setEnabled(false);
agreebutton.setTextColor(getResources().getColor(android.R.color.white));
agreebutton.setBackgroundColor(getResources().getColor(android.R.color.darker_gray));
}
}
});