scrollview inside viewpager not scrolling

Question

I have a small vertical scrollview inside a viewpager with horizontal swippable pages. The problem is that currently i am not able to scroll through the pages by swiping horizontally over the scrollview. I want to be able to swipe horizontally over the scrollview to scroll through viewpager's pages and also have the function to swipe vertically to scroll through the scrollview's contents.

Genie

Answer 1

You can do it with the following custom scrollview

public class CustomScrollView extends ScrollView {
    private GestureDetector mGestureDetector;

    public CustomScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mGestureDetector = new GestureDetector(context, new YScrollDetector());
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        return super.onInterceptTouchEvent(ev) && mGestureDetector.onTouchEvent(ev);
    }

    // Return false if we're scrolling in the x direction  
    class YScrollDetector extends SimpleOnGestureListener {
        @Override
        public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
            return Math.abs(distanceY) > Math.abs(distanceX);
        }
    }
}

Olgaolguin

I tried it but it made no difference. The horizontal ViewPager contains 2 buttons and a scrollview. If i swipe horizontally over the buttons the viewpager pages scroll but if i do it over the scrollview then nothing happens but i can still scroll through the scrollview – Genie

Answer 2

I don´t know if it's the same case, but I had a similar problem that you have described. I have looked everywhere to find this answer: https://mcmap.net/q/1666062/-scrollview-inside-a-fragment-with-tablayout-is-not-scrolling-why.

Basically, if your Activity structure is like above example:

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            android:elevation="4dp"
            android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>

        <android.support.design.widget.TabLayout
            android:id="@+id/tab_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/toolbar"
            android:background="?attr/colorPrimary"
            android:elevation="6dp"
            android:minHeight="?attr/actionBarSize"
            app:tabMode="fixed"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"/>

        <android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:tools="http://schemas.android.com/tools"
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_below="@+id/toolbar"
            tools:context="net.voidynullness.android.tabitytabs.TabLayoutActivity"
                                           android:background="#ffffff"/>

    </android.support.design.widget.AppBarLayout>

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="@dimen/fab_margin"
        android:src="@android:drawable/ic_dialog_info"/>
</android.support.design.widget.CoordinatorLayout>

Change to (Look "android.support.design.widget.AppBarLayout"):

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            android:elevation="4dp"
            android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>

        <android.support.design.widget.TabLayout
            android:id="@+id/tab_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/toolbar"
            android:background="?attr/colorPrimary"
            android:elevation="6dp"
            android:minHeight="?attr/actionBarSize"
            app:tabMode="fixed"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"/>
    </android.support.design.widget.AppBarLayout>

        <android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:tools="http://schemas.android.com/tools"
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_below="@+id/toolbar"
            tools:context="net.voidynullness.android.tabitytabs.TabLayoutActivity"
                                           android:background="#ffffff"/>

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="@dimen/fab_margin"
        android:src="@android:drawable/ic_dialog_info"/>
</android.support.design.widget.CoordinatorLayout>

Now, you'll able to swipe horizontally and vertically!

Lingle

Do you mean horizontally and vertically? – Seaquake

Sorry @bwegs, fixed! – Lingle