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    <p>Here's my attempt at gallery that works with vertical <code>ScrollViews</code>.</p> <p>It uses its own instance of <code>GestureDetector</code> and feeds it with <code>MotionEvents</code> from <code>onInterceptTouchEvent</code>. </p> <p>When gesture detector recognizes a scroll, we determine whether it's horizontal or vertical and lock on the direction until the gesture is finished. This avoids diagonal scrolling. </p> <p>If it's a horizontal scroll, <code>onInterceptTouchEvent</code> will return true so that future motion events go to inherited <code>Gallery.onTouchEvent</code> to do the actual scrolling.</p> <p><code>Gallery</code>'s own gesture detector (<code>mGestureDetector</code> in <code>Gallery.java</code>) doesn't get all motion events and thus sometimes reports huge sudden scrolls that cause gallery to jump around. I've put in a a nasty hack that discards those. </p> <p>The code:</p> <pre><code>import android.content.Context; import android.util.AttributeSet; import android.view.GestureDetector; import android.view.MotionEvent; import android.widget.Gallery; public class BetterGallery extends Gallery { /* This gets set when we detect horizontal scrolling */ private boolean scrollingHorizontally = false; /* This gets set during vertical scrolling. We use this to avoid detecting * horizontal scrolling when vertical scrolling is already in progress * and vice versa. */ private boolean scrollingVertically = false; /* Our own gesture detector, Gallery's mGestureDetector is private. * We'll feed it with motion events from `onInterceptTouchEvent` method. */ private GestureDetector mBetterGestureDetector; public BetterGallery(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); mBetterGestureDetector = new GestureDetector(new BetterGestureListener()); } public BetterGallery(Context context, AttributeSet attrs) { super(context, attrs); mBetterGestureDetector = new GestureDetector(new BetterGestureListener()); } public BetterGallery(Context context) { super(context); mBetterGestureDetector = new GestureDetector(new BetterGestureListener()); } @Override public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { // Limit velocity so we don't fly over views return super.onFling(e1, e2, 0, velocityY); } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { // Documentation on this method's contract: // http://developer.android.com/reference/android/view/ViewGroup.html#onInterceptTouchEvent(android.view.MotionEvent) // Reset our scrolling flags if ACTION_UP or ACTION_CANCEL switch (ev.getAction()) { case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: scrollingHorizontally = false; scrollingVertically = false; } // Feed our gesture detector mBetterGestureDetector.onTouchEvent(ev); // Intercept motion events if horizontal scrolling is detected return scrollingHorizontally; } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { // Hack: eat jerky scrolls caused by stale state in mGestureDetector // which we cannot directly access if (Math.abs(distanceX) &gt; 100) return false; return super.onScroll(e1, e2, distanceX, distanceY); } @Override public boolean onTouchEvent(MotionEvent event) { // Reset our scrolling flags if ACTION_UP or ACTION_CANCEL switch(event.getAction()) { case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: scrollingHorizontally = false; scrollingVertically = false; } super.onTouchEvent(event); return scrollingHorizontally; } private class BetterGestureListener implements GestureDetector.OnGestureListener { @Override public boolean onDown(MotionEvent arg0) { return false; } @Override public boolean onFling(MotionEvent arg0, MotionEvent arg1, float arg2, float arg3) { return false; } @Override public void onLongPress(MotionEvent arg0) { } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { if (scrollingHorizontally || scrollingVertically) { // We already know we're scrolling, ignore this callback. // This avoids changing scrollingHorizontally / scrollingVertically // flags mid-scroll. return false; } scrollingHorizontally |= Math.abs(distanceX) &gt; Math.abs(distanceY); // It's a scroll, and if it's not horizontal, then it has to be vertical scrollingVertically = !scrollingHorizontally; return false; } @Override public void onShowPress(MotionEvent arg0) { } @Override public boolean onSingleTapUp(MotionEvent arg0) { return false; } } } </code></pre> <p>Warning: word "Better" in class name is likely misleading!</p> <p><strong>Update:</strong></p> <p>Forgot to mention, I've also set the activity to forward its <code>onTouchEvent</code> to gallery:</p> <pre><code>@Override public boolean onTouchEvent(MotionEvent event) { return mGallery.onTouchEvent(event); } </code></pre> <p><strong>Update 2:</strong></p> <p>I've made some improvements to this code and put it up on <a href="https://bitbucket.org/cuu508/friendlygallery" rel="nofollow noreferrer">bitbucket</a>. There's also an example app. It demonstrates that this widget has issues with ListView as child :-/</p> <p><img src="https://i.stack.imgur.com/qx2Cx.png" alt="enter image description here"></p> <p><strong>Update 3:</strong></p> <p>Switched from <code>Gallery</code> to <code>HorizontalScrollView</code> as the base class for my custom widget. <a href="http://cuu508.wordpress.com/2011/07/20/horizontal-scrolling-widget-based-on-horizontalscrollview/" rel="nofollow noreferrer">More on this here</a>. Flings work, ListViews and ExpandableListViews as children work, tested on Android 1.6, 2.2, 2.3.4. Its behaviour is now quite close to that of Google apps, IMO.</p> <p><strong>Update 4:</strong></p> <p>Google has published <a href="http://android-developers.blogspot.com/2011/08/horizontal-view-swiping-with-viewpager.html" rel="nofollow noreferrer">ViewPager</a>!</p>
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    1. POScrollView and Gallery interfering
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    1. CO+1 this solution worked for me, i recommend it :)
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      1. USMohammad Ersan
    2. CObut there is little problem, sometime it stuck, or been un-sensitive
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      1. USMohammad Ersan
    3. CO@MoshErsan: initially forgot to mention I'm forwarding `onTouchEvent` from activity to gallery. That might help.
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