"how to repeat function on long click in android" Code Answer's

how to repeat function on long click in android

By Stockholm on Dec 24, 2020

import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;

/**
 * A class, that can be used as a TouchListener on any view (e.g. a Button).
 * It cyclically runs a clickListener, emulating keyboard-like behaviour. First
 * click is fired immediately, next one after the initialInterval, and subsequent
 * ones after the normalInterval.
 *
 * <p>Interval is scheduled after the onClick completes, so it has to run fast.
 * If it runs slow, it does not generate skipped onClicks. Can be rewritten to
 * achieve this.
 */
public class RepeatListener implements OnTouchListener {

    private Handler handler = new Handler();

    private int initialInterval;
    private final int normalInterval;
    private final OnClickListener clickListener;
    private View touchedView;

    private Runnable handlerRunnable = new Runnable() {
        @Override
        public void run() {
            if(touchedView.isEnabled()) {
                handler.postDelayed(this, normalInterval);
                clickListener.onClick(touchedView);
            } else {
                // if the view was disabled by the clickListener, remove the callback
                handler.removeCallbacks(handlerRunnable);
                touchedView.setPressed(false);
                touchedView = null;
            }
        }
    };

    /**
     * @param initialInterval The interval after first click event
     * @param normalInterval The interval after second and subsequent click 
     *       events
     * @param clickListener The OnClickListener, that will be called
     *       periodically
     */
    public RepeatListener(int initialInterval, int normalInterval, 
            OnClickListener clickListener) {
        if (clickListener == null)
            throw new IllegalArgumentException("null runnable");
        if (initialInterval < 0 || normalInterval < 0)
            throw new IllegalArgumentException("negative interval");

        this.initialInterval = initialInterval;
        this.normalInterval = normalInterval;
        this.clickListener = clickListener;
    }

    public boolean onTouch(View view, MotionEvent motionEvent) {
        switch (motionEvent.getAction()) {
        case MotionEvent.ACTION_DOWN:
            handler.removeCallbacks(handlerRunnable);
            handler.postDelayed(handlerRunnable, initialInterval);
            touchedView = view;
            touchedView.setPressed(true);
            clickListener.onClick(view);
            return true;
        case MotionEvent.ACTION_UP:
        case MotionEvent.ACTION_CANCEL:
            handler.removeCallbacks(handlerRunnable);
            touchedView.setPressed(false);
            touchedView = null;
            return true;
        }

        return false;
    }

}

Usage:

Button button = new Button(context);
button.setOnTouchListener(new RepeatListener(400, 100, new OnClickListener() {
  @Override
  public void onClick(View view) {
    // the code to execute repeatedly
  }
}));

Source: stackoverflow.com

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