Other Add SwipeToRefresh to your views

DonManfred

Expert
Licensed User
Basically this i this Java-Class

B4X:
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ValueAnimator;
import android.app.ListActivity;
import android.app.ListFragment;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ListView;

/**
* A {@link View.OnTouchListener} that makes any {@link View} dismissable when the
* user swipes (drags her finger) horizontally across the view.
*
* <p><em>For {@link ListView} list items that don't manage their own touch events
* (i.e. you're using
* {@link ListView#setOnItemClickListener(AdapterView.OnItemClickListener)}
* or an equivalent listener on {@link ListActivity} or
* {@link ListFragment}, use {@link SwipeDismissListViewTouchListener} instead.</em></p>
*
* <p>Example usage:</p>
*
* <pre>
* view.setOnTouchListener(new SwipeDismissTouchListener(
*         view,
*         null, // Optional token/cookie object
*         new SwipeDismissTouchListener.OnDismissCallback() {
*             public void onDismiss(View view, Object token) {
*                 parent.removeView(view);
*             }
*         }));
* </pre>
*
* <p>This class Requires API level 12 or later due to use of {@link
* android.view.ViewPropertyAnimator}.</p>
*
* @see SwipeDismissListViewTouchListener
*/
public class SwipeDismissTouchListener implements View.OnTouchListener {
    // Cached ViewConfiguration and system-wide constant values
    private int mSlop;
    private int mMinFlingVelocity;
    private int mMaxFlingVelocity;
    private long mAnimationTime;

    // Fixed properties
    private View mView;
    private DismissCallbacks mCallbacks;
    private int mViewWidth = 1; // 1 and not 0 to prevent dividing by zero

    // Transient properties
    private float mDownX;
    private float mDownY;
    private boolean mSwiping;
    private int mSwipingSlop;
    private Object mToken;
    private VelocityTracker mVelocityTracker;
    private float mTranslationX;

    /**
     * The callback interface used by {@link SwipeDismissTouchListener} to inform its client
     * about a successful dismissal of the view for which it was created.
     */
    public interface DismissCallbacks {
        /**
         * Called to determine whether the view can be dismissed.
         */
        boolean canDismiss(Object token);

        /**
         * Called when the user has indicated they she would like to dismiss the view.
         *
         * @param view  The originating {@link View} to be dismissed.
         * @param token The optional token passed to this object's constructor.
         */
        void onDismiss(View view, Object token);
    }

    /**
     * Constructs a new swipe-to-dismiss touch listener for the given view.
     *
     * @param view     The view to make dismissable.
     * @param token    An optional token/cookie object to be passed through to the callback.
     * @param callbacks The callback to trigger when the user has indicated that she would like to
     *                 dismiss this view.
     */
    public SwipeDismissTouchListener(View view, Object token, DismissCallbacks callbacks) {
        ViewConfiguration vc = ViewConfiguration.get(view.getContext());
        mSlop = vc.getScaledTouchSlop();
        mMinFlingVelocity = vc.getScaledMinimumFlingVelocity() * 16;
        mMaxFlingVelocity = vc.getScaledMaximumFlingVelocity();
        mAnimationTime = view.getContext().getResources().getInteger(
                android.R.integer.config_shortAnimTime);
        mView = view;
        mToken = token;
        mCallbacks = callbacks;
    }

    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
        // offset because the view is translated during swipe
        motionEvent.offsetLocation(mTranslationX, 0);

        if (mViewWidth < 2) {
            mViewWidth = mView.getWidth();
        }

        switch (motionEvent.getActionMasked()) {
            case MotionEvent.ACTION_DOWN: {
                // TODO: ensure this is a finger, and set a flag
                mDownX = motionEvent.getRawX();
                mDownY = motionEvent.getRawY();
                if (mCallbacks.canDismiss(mToken)) {
                    mVelocityTracker = VelocityTracker.obtain();
                    mVelocityTracker.addMovement(motionEvent);
                }
                return false;
            }

            case MotionEvent.ACTION_UP: {
                if (mVelocityTracker == null) {
                    break;
                }

                float deltaX = motionEvent.getRawX() - mDownX;
                mVelocityTracker.addMovement(motionEvent);
                mVelocityTracker.computeCurrentVelocity(1000);
                float velocityX = mVelocityTracker.getXVelocity();
                float absVelocityX = Math.abs(velocityX);
                float absVelocityY = Math.abs(mVelocityTracker.getYVelocity());
                boolean dismiss = false;
                boolean dismissRight = false;
                if (Math.abs(deltaX) > mViewWidth / 2 && mSwiping) {
                    dismiss = true;
                    dismissRight = deltaX > 0;
                } else if (mMinFlingVelocity <= absVelocityX && absVelocityX <= mMaxFlingVelocity
                        && absVelocityY < absVelocityX
                        && absVelocityY < absVelocityX && mSwiping) {
                    // dismiss only if flinging in the same direction as dragging
                    dismiss = (velocityX < 0) == (deltaX < 0);
                    dismissRight = mVelocityTracker.getXVelocity() > 0;
                }
                if (dismiss) {
                    // dismiss
                    mView.animate()
                            .translationX(dismissRight ? mViewWidth : -mViewWidth)
                            .alpha(0)
                            .setDuration(mAnimationTime)
                            .setListener(new AnimatorListenerAdapter() {
                                @Override
                                public void onAnimationEnd(Animator animation) {
                                    performDismiss();
                                }
                            });
                } else if (mSwiping) {
                    // cancel
                    mView.animate()
                            .translationX(0)
                            .alpha(1)
                            .setDuration(mAnimationTime)
                            .setListener(null);
                }
                mVelocityTracker.recycle();
                mVelocityTracker = null;
                mTranslationX = 0;
                mDownX = 0;
                mDownY = 0;
                mSwiping = false;
                break;
            }

            case MotionEvent.ACTION_CANCEL: {
                if (mVelocityTracker == null) {
                    break;
                }

                mView.animate()
                        .translationX(0)
                        .alpha(1)
                        .setDuration(mAnimationTime)
                        .setListener(null);
                mVelocityTracker.recycle();
                mVelocityTracker = null;
                mTranslationX = 0;
                mDownX = 0;
                mDownY = 0;
                mSwiping = false;
                break;
            }

            case MotionEvent.ACTION_MOVE: {
                if (mVelocityTracker == null) {
                    break;
                }

                mVelocityTracker.addMovement(motionEvent);
                float deltaX = motionEvent.getRawX() - mDownX;
                float deltaY = motionEvent.getRawY() - mDownY;
                if (Math.abs(deltaX) > mSlop && Math.abs(deltaY) < Math.abs(deltaX) / 2) {
                    mSwiping = true;
                    mSwipingSlop = (deltaX > 0 ? mSlop : -mSlop);
                    mView.getParent().requestDisallowInterceptTouchEvent(true);

                    // Cancel listview's touch
                    MotionEvent cancelEvent = MotionEvent.obtain(motionEvent);
                    cancelEvent.setAction(MotionEvent.ACTION_CANCEL |
                            (motionEvent.getActionIndex() <<
                                    MotionEvent.ACTION_POINTER_INDEX_SHIFT));
                    mView.onTouchEvent(cancelEvent);
                    cancelEvent.recycle();
                }

                if (mSwiping) {
                    mTranslationX = deltaX;
                    mView.setTranslationX(deltaX - mSwipingSlop);
                    // TODO: use an ease-out interpolator or such
                    mView.setAlpha(Math.max(0f, Math.min(1f,
                            1f - 2f * Math.abs(deltaX) / mViewWidth)));
                    return true;
                }
                break;
            }
        }
        return false;
    }

    private void performDismiss() {
        // Animate the dismissed view to zero-height and then fire the dismiss callback.
        // This triggers layout on each animation frame; in the future we may want to do something
        // smarter and more performant.

        final ViewGroup.LayoutParams lp = mView.getLayoutParams();
        final int originalHeight = mView.getHeight();

        ValueAnimator animator = ValueAnimator.ofInt(originalHeight, 1).setDuration(mAnimationTime);

        animator.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationEnd(Animator animation) {
                mCallbacks.onDismiss(mView, mToken);
                // Reset view presentation
                mView.setAlpha(1f);
                mView.setTranslationX(0);
                lp.height = originalHeight;
                mView.setLayoutParams(lp);
            }
        });

        animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator valueAnimator) {
                lp.height = (Integer) valueAnimator.getAnimatedValue();
                mView.setLayoutParams(lp);
            }
        });

        animator.start();
    }
}
Save it into a java file and add this file to your Project

Assuming your view is instanced into the variable "v"
The view is given as parameter too (to be used in the Events)
tag is another parameter you can use to set a Tag to this view which then will be used in the events too.

B4X:
        v.setOnTouchListener((new SwipeDismissTouchListener(
                v,
                tag,
        new SwipeDismissTouchListener.DismissCallbacks() {
            @Override
            public boolean canDismiss(Object token) {
                return true;
            }

            @Override
            public void onDismiss(View view, Object token) {
                ba.raiseEvent(ba.context, eventName+"_ondismiss", token);
                //ba.raiseEventFromDifferentThread(ba.context, null, 0, eventName + "_ondismiss", true, new Object[] {token});
                view.setVisibility(4); 
                //dismissableContainer.removeView(dismissableButton);
            }
        })));
 
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