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@Nilzor
Created January 31, 2016 10:25
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Tow-way data bound string, based on Blog by Fabio Colini
<?xml version="1.0" encoding="utf-8"?>
<!-- Put this in /res/values -->
<resources>
<item name="textBound" type="id" />
</resources>
import android.databinding.BaseObservable;
import android.databinding.BindingAdapter;
import android.databinding.BindingConversion;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
import java.io.Serializable;
/**
* An observable class that holds a String, including event listener logic that will
* set data back to the observable upon change in the UI layer.
*
* Credits to Fabio Collini https://medium.com/@fabioCollini/android-data-binding-f9f9d3afc761#.7xkobedbt
*/
public class TwoWayBoundString extends BaseObservable implements Serializable {
static final long serialVersionUID = 1L;
private String mValue;
/**
* Creates an empty observable object
*/
public TwoWayBoundString() {
}
/**
* Wraps the given object and creates an observable object
*
* @param value The value to be wrapped as an observable.
*/
public TwoWayBoundString(String value) {
mValue = value;
}
/**
* @return the stored value.
*/
public String get() {
return mValue;
}
/**
* Set the stored value.
*/
public void set(String value) {
if (value == null && mValue == null) return;
if ((value == null && mValue != null) || !value.equals(mValue)) {
mValue = value;
notifyChange();
}
}
/** Sets the stored value without notifying of change */
public void setSilently(String value) {
mValue = value;
}
@BindingAdapter({"android:text"})
public static void bindEditText(EditText view, final TwoWayBoundString twoWayBoundString) {
if (view.getTag(R.id.textBound) == null) {
// Hook up chanbge listeners upon first initialization
view.setTag(R.id.textBound, true);
view.addTextChangedListener(new TextWatcher() {
@Override
public void afterTextChanged(Editable s) {
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
twoWayBoundString.set(s.toString());
}
});
}
String newValue = twoWayBoundString.get();
if (!view.getText().toString().equals(newValue)) {
view.setText(newValue);
}
}
// Fallback one-way binding for non-text String attributes, like "android:hint"
@BindingConversion
public static String observableStringToString(TwoWayBoundString string) {
return string.get();
}
}
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