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@marteinn
Last active May 2, 2023 22:35
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ScrollView with a OnBottomReachedListener for Android. MIT license (https://opensource.org/licenses/MIT).
package se.marteinn.ui;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.widget.ScrollView;
/**
* Triggers a event when scrolling reaches bottom.
*
* Created by martinsandstrom on 2010-05-12.
* Updated by martinsandstrom on 2014-07-22.
*
* Usage:
*
* scrollView.setOnBottomReachedListener(
* new InteractiveScrollView.OnBottomReachedListener() {
* @Override
* public void onBottomReached() {
* // do something
* }
* }
* );
*
*
* Include in layout:
*
* <se.marteinn.ui.InteractiveScrollView
* android:layout_width="match_parent"
* android:layout_height="match_parent" />
*
*/
public class InteractiveScrollView extends ScrollView {
OnBottomReachedListener mListener;
public InteractiveScrollView(Context context, AttributeSet attrs,
int defStyle) {
super(context, attrs, defStyle);
}
public InteractiveScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public InteractiveScrollView(Context context) {
super(context);
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
View view = (View) getChildAt(getChildCount()-1);
int diff = (view.getBottom()-(getHeight()+getScrollY()));
if (diff == 0 && mListener != null) {
mListener.onBottomReached();
}
super.onScrollChanged(l, t, oldl, oldt);
}
// Getters & Setters
public OnBottomReachedListener getOnBottomReachedListener() {
return mListener;
}
public void setOnBottomReachedListener(
OnBottomReachedListener onBottomReachedListener) {
mListener = onBottomReachedListener;
}
/**
* Event listener.
*/
public interface OnBottomReachedListener{
public void onBottomReached();
}
}
@Croydon
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Croydon commented Nov 16, 2017

@marteinn Under which license do you publish this?

@marteinn
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Author

@Croydon MIT. Will clarify in the description.

@sevar83
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sevar83 commented Feb 17, 2018

One-liner in Kotlin:

fun ViewGroup.isScrolledToBottom() = getChildAt(childCount - 1).bottom - height - scrollY == 0

@wahyuade
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wahyuade commented Mar 1, 2018

good, it's work

@jemshit
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jemshit commented Apr 25, 2018

topReach is fired multiple times

@klaszlo8207
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klaszlo8207 commented Jul 30, 2018

fixed version

public class MyScrollView extends ScrollView {

OnBottomReachedListener mListener;

private boolean bottomreached = false;

public MyStickyScrollView(Context context, AttributeSet attrs,
                          int defStyle) {
    super(context, attrs, defStyle);
}

public MyStickyScrollView(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public MyStickyScrollView(Context context) {
    super(context);
}

@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
    View view = getChildAt(getChildCount()-1);
    int diff = (view.getBottom()-(getHeight()+getScrollY()));

    if (diff == 0 && mListener != null && !bottomreached) {
        mListener.onBottomReached();
        bottomreached = true;
    }
    else {
        bottomreached = false;
    }

    super.onScrollChanged(l, t, oldl, oldt);
}

// Getters & Setters
public OnBottomReachedListener getOnBottomReachedListener() {
    return mListener;
}

public void setOnBottomReachedListener(
        OnBottomReachedListener onBottomReachedListener) {
    mListener = onBottomReachedListener;
}


/**
 * Event listener.
 */
public interface OnBottomReachedListener{
    void onBottomReached();
}

}
only fires 1 time

@mecoFarid
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diff ==0 is dangerous because it may never hit 0 as of various brand screen configurations. diff <= 0 is kinda useless because it's gonna trigger top/bottomReached multiple times.

@Wizard254
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So far, great thanks for your work, works just as expected.

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