Webview Inside Nestedscrollview Cannot Be Scrolled

I've got an activity that use WebView to load the web content. The problem arise when I want to implement Flexible Space with image. I can expand and collapse the Toolbar, but when

Solution 1:

By the usage of NestedScrollingChild Interface, we can implements the NestedScrollView properties in the webview. And customize the scrolling functionality under the onTouchEvent() method.

publicclassNestedWebViewextendsWebViewimplementsNestedScrollingChild {
    privateint mLastY;
    privatefinalint[] mScrollOffset = newint[2];
    privatefinalint[] mScrollConsumed = newint[2];
    privateint mNestedOffsetY;
    private NestedScrollingChildHelper mChildHelper;

    publicNestedWebView(Context context) {
        this(context, null);
    }

    publicNestedWebView(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.webViewStyle);
    }

    publicNestedWebView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        mChildHelper = newNestedScrollingChildHelper(this);
        setNestedScrollingEnabled(true);
    }

    @OverridepublicbooleanonTouchEvent(MotionEvent ev) {
        booleanreturnValue=false;

        MotionEventevent= MotionEvent.obtain(ev);
        finalintaction= MotionEventCompat.getActionMasked(event);
        if (action == MotionEvent.ACTION_DOWN) {
            mNestedOffsetY = 0;
        }
        inteventY= (int) event.getY();
        event.offsetLocation(0, mNestedOffsetY);
        switch (action) {
            case MotionEvent.ACTION_MOVE:
                inttotalScrollOffset=0;
                intdeltaY= mLastY - eventY;
                // NestedPreScrollif (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset)) {
                    totalScrollOffset += mScrollOffset[1];
                    deltaY -= mScrollConsumed[1];
                    event.offsetLocation(0, -mScrollOffset[1]);
                    mNestedOffsetY += mScrollOffset[1];
                }
                returnValue = super.onTouchEvent(event);

                // NestedScrollif (dispatchNestedScroll(0, mScrollOffset[1], 0, deltaY, mScrollOffset)) {
                    totalScrollOffset += mScrollOffset[1];
                    event.offsetLocation(0, mScrollOffset[1]);
                    mNestedOffsetY += mScrollOffset[1];
                    mLastY -= mScrollOffset[1];
                }
                mLastY = eventY - totalScrollOffset;
                break;
            case MotionEvent.ACTION_DOWN:
                returnValue = super.onTouchEvent(event);
                mLastY = eventY;
                // start NestedScroll
                startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                returnValue = super.onTouchEvent(event);
                // end NestedScroll
                stopNestedScroll();
                break;
        }
        return returnValue;
    }

    // Nested Scroll implements@OverridepublicvoidsetNestedScrollingEnabled(boolean enabled) {
        mChildHelper.setNestedScrollingEnabled(enabled);
    }

    @OverridepublicbooleanisNestedScrollingEnabled() {
        return mChildHelper.isNestedScrollingEnabled();
    }

    @OverridepublicbooleanstartNestedScroll(int axes) {
        return mChildHelper.startNestedScroll(axes);
    }

    @OverridepublicvoidstopNestedScroll() {
        mChildHelper.stopNestedScroll();
    }

    @OverridepublicbooleanhasNestedScrollingParent() {
        return mChildHelper.hasNestedScrollingParent();
    }

    @OverridepublicbooleandispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed,
                                        int[] offsetInWindow) {
        return mChildHelper.dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, offsetInWindow);
    }

    @OverridepublicbooleandispatchNestedPreScroll(int dx, int dy, int[] consumed, int[] offsetInWindow) {
        return mChildHelper.dispatchNestedPreScroll(dx, dy, consumed, offsetInWindow);
    }

    @OverridepublicbooleandispatchNestedFling(float velocityX, float velocityY, boolean consumed) {
        return mChildHelper.dispatchNestedFling(velocityX, velocityY, consumed);
    }

    @OverridepublicbooleandispatchNestedPreFling(float velocityX, float velocityY) {
        return mChildHelper.dispatchNestedPreFling(velocityX, velocityY);
    }

}

Declare NestedWebView instead of declaring webview inside the NestedScrollView.For example,

<com.nestedscrollwebviewexample.NestedWebView
        android:id="@+id/nested_webview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#000000"
        android:fillViewport="true"
        android:focusable="true"
        android:isScrollContainer="false"
        android:visibility="visible"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        app:layout_scrollFlags="scroll|exitUntilCollapsed" />

Instead of declaring Webview you can initialize as NestedWebView inside your Activity

private NestedWebView mShopWebView;
        mShopWebView = (NestedWebView) findViewById(R.id.url_load_webview);

Solution 2:

Got this one working with changing the height attribute of the underlying Webview.

For NestedScrollView use attribute

android:fillViewport="true"

and for WebView use android:layout_height="wrap_content"

Full Answer here

Solution 3:

I faced a similar problem but I solved it on multiple Android versions by using the following custom WebView class which manages the touch events:

import android.content.Context;
import android.support.v4.view.MotionEventCompat;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.webkit.WebView;

/**
 * Created by pk on 10/16/16.
 * Creates a WebView that can be used inside a ScrollView
 */publicclassCustomWebViewextendsWebView {

    publicCustomWebView(Context context) {
        super(context);
    }

    publicCustomWebView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    publicCustomWebView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @OverridepublicbooleanonTouchEvent(MotionEvent event) {

        //Check pointer index to avoid -1 (error)if (MotionEventCompat.findPointerIndex(event, 0) == -1) {
            returnsuper.onTouchEvent(event);
        }

        if (event.getPointerCount() >= 2) {
            requestDisallowInterceptTouchEvent(true);
        } else {
            requestDisallowInterceptTouchEvent(false);
        }

        returnsuper.onTouchEvent(event);
    }

    @OverrideprotectedvoidonOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) {
        super.onOverScrolled(scrollX, scrollY, clampedX, clampedY);
        requestDisallowInterceptTouchEvent(true);


    }
}

Solution 4:

Just make NestedScrollView fillViewport = "false" and WebView layout_height = "wrap_content"

<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"android:layout_height="match_parent"android:fillViewport="false"app:layout_behavior="@string/appbar_scrolling_view_behavior">

<WebView
    android:id="@+id/read_full_content_wv"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

Solution 5:

Answer : Just change webView's height match_parent to wrap_content .

When you do height = "match_parent" then webview Not scroll in ScrollView

        android:id="@+id/read_full_content_wv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"// just change height of webView
/> ```