How to change/override the Checkbox content description value, when accessibility turned on?

user_4424270 0
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I have a checkbox in my activity and provided android:contentDescription="selected". Also in java class provided as below. 

checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
    @Override
    public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
        checkbox.setContentDescription(b ? "Selected" : "Not Selected");
    }
});

When i turn on talkback and selected the checkbox, then it says "Checked/Not Checked" instead of "Selected/Not Selected".

It is taking default values of OS (Varies in different manufacturers and OS version) but not provided values. Is there any way, we can fix this issue?

accessibility android
1 Answers

So I ran into this issue a while back and found a rather hacky workaround. Create and use a subclass of CheckBox like this and replace the strings:

public class CustomCheckBox extends CheckBox {

    // constructors...

    @Override
    public CharSequence getAccessibilityClassName() {
        // override to disable the "checkbox" readout
        return CustomCheckBox.class.getSimpleName();
    }

    @Override
    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
        super.onInitializeAccessibilityNodeInfo(info);
        // by setting checkable to false the default checked/unchecked readouts are disabled
        info.setCheckable(false);
        // ...and then you can set whatever you want as a text
        info.setText(getStateDescription());
    }

    @Override
    public void setChecked(boolean checked) {
        if (checked == isChecked()) return;
        super.setChecked(checked);
        // since we've disabled the checked/unchecked readouts
        // we are forced to manually announce changes to the state
        announceForAccessibility(getStateDescription());
    }

    private String getStateDescription() {
        if (isChecked()) {
            return "Custom checked description";
        } else {
            return "Custom unchecked description";
        }
    }
}

Also I should start this off by saying I haven't tried the stuff mentioned below, but it seems that Android R (API 30) adds an official way to override this by adding setStateDescription(CharSequence) to CompoundButton Source Doc

/**
 * This function is called when an instance or subclass sets the state description. Once this
 * is called and the argument is not null, the app developer will be responsible for updating
 * state description when checked state changes and we will not set state description
 * in {@link #setChecked}. App developers can restore the default behavior by setting the
 * argument to null. If {@link #setChecked} is called first and then setStateDescription is
 * called, two state change events will be merged by event throttling and we can still get
 * the correct state description.
 *
 * @param stateDescription The state description.
 */
@Override
public void setStateDescription(@Nullable CharSequence stateDescription) {
    mCustomStateDescription = stateDescription;
    if (stateDescription == null) {
        setDefaultStateDescritption();
    } else {
        super.setStateDescription(stateDescription);
    }
}
user_22817180
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