[SNIPPET] Direzione di Scrolling di una ListView - [Scroll up|down|bottom|top]

[cesco]

ciao a tutti

Eccovi un altro snippet di codice contenente una ListView e un listener custom la direzione di scroll della listView che ho dovuto implementare per necessità

Buon coding

	list.setOnDetectScrollListener(new OnDetectScrollListener() {
	@Override
	public void onUpScrolling() {
	// TODO Auto-generated method stub
	mBottom.setVisibility(View.VISIBLE);
	}
	@Override
	public void onDownScrolling() {
	// TODO Auto-generated method stub
	mBottom.setVisibility(View.GONE);
	}
	@Override
	public void onBottomScrolled() {
	// TODO Auto-generated method stub
	mBottom.setVisibility(View.VISIBLE);
	}
	@Override
	public void onTopScrolled() {
	// TODO Auto-generated method stub
	mBottom.setVisibility(View.VISIBLE);
	}
	});

view raw ImplementationSample.java hosted with ❤ by GitHub

	public interface OnDetectScrollListener {
	void onUpScrolling();
	void onDownScrolling();
	void onBottomScrolled();
	void onTopScrolled();
	}

view raw OnDetectScrollListener.java hosted with ❤ by GitHub

	import android.content.Context;
	import android.util.AttributeSet;
	import android.view.View;
	import android.widget.AbsListView;
	public class ScrollDetectableListView extends android.widget.ListView {
	private OnScrollListener onScrollListener;
	private OnDetectScrollListener onDetectScrollListener;
	public ScrollDetectableListView(Context context) {
	super(context);
	onCreate(context, null, null);
	}
	public ScrollDetectableListView(Context context, AttributeSet attrs) {
	super(context, attrs);
	onCreate(context, attrs, null);
	}
	public ScrollDetectableListView(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);
	onCreate(context, attrs, defStyle);
	}
	@SuppressWarnings("UnusedParameters")
	private void onCreate(Context context, AttributeSet attrs, Integer defStyle) {
	setListeners();
	}
	private void setListeners() {
	super.setOnScrollListener(new OnScrollListener() {
	private int oldTop;
	private int oldFirstVisibleItem;
	@Override
	public void onScrollStateChanged(AbsListView view, int scrollState) {
	if (onScrollListener != null) {
	onScrollListener.onScrollStateChanged(view, scrollState);
	}
	}
	@Override
	public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
	if (onScrollListener != null) {
	onScrollListener.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount);
	}
	if (onDetectScrollListener != null) {
	onDetectedListScroll(view, firstVisibleItem, totalItemCount, visibleItemCount);
	}
	}
	private void onDetectedListScroll(AbsListView absListView, int firstVisibleItem, int totalItemCount, int visibleItemCount) {
	View view = absListView.getChildAt(0);
	int top = (view == null) ? 0 : view.getTop();
	int lastItem = firstVisibleItem + visibleItemCount;
	if (firstVisibleItem == oldFirstVisibleItem) {
	if (top > oldTop) {
	onDetectScrollListener.onUpScrolling();
	} else if (top < oldTop) {
	onDetectScrollListener.onDownScrolling();
	}
	} else {
	if (firstVisibleItem < oldFirstVisibleItem) {
	onDetectScrollListener.onUpScrolling();
	} else {
	onDetectScrollListener.onDownScrolling();
	}
	}
	if(lastItem == totalItemCount) {
	if(oldFirstVisibleItem <= lastItem){
	onDetectScrollListener.onBottomScrolled();
	}else {
	onDetectScrollListener.onUpScrolling();
	}
	}
	oldTop = top;
	oldFirstVisibleItem = firstVisibleItem;
	}
	});
	}
	@Override
	public void setOnScrollListener(OnScrollListener onScrollListener) {
	this.onScrollListener = onScrollListener;
	}
	public void setOnDetectScrollListener(OnDetectScrollListener onDetectScrollListener) {
	this.onDetectScrollListener = onDetectScrollListener;
	}
	}

view raw ScrollDetectableListView.java hosted with ❤ by GitHub