Stop ScrollView from auto-scrolling to an EditText

问题:

Seems to be a common problem without a great solution that I have found. Goal is to stop a ScrollView from auto-scrolling to an EditText (or any view for that matter) that has focus.

You have a bunch of views (Buttons, TextViews, etc) in an ScrollView, one of which is an EditText. Upon clicking say a Button within the ScrollView, the ScrollView scrolls down to the EditText (its off screen). This is not desired, as there are other elements that you don't want scrolled off the screen.

Now I can stop this from happening when the screen first shows by having other focusable elements in the ScrollView. However, the general problem still exists. The user scrolls down manually to the EditText, enters some numbers, then scrolls up to the top (EditText off screen now), they click a button in the ScrollView, and guess what? The ScrollView scrolls down to that darn EditText.

I'm thinking about extending the ScrollView and overriding some of the methods there like findFocusableViewInBounds, but I have a feeling I'll just be getting myself into more trouble.

Please help if you can.

I've played around with things like having an 0 height EditText at the top of my ScrollView, adding Next Focusable element properties to the other items in the ScrollView, etc. I suppose one "hack" might be to get the EditText to lose focus when the virtual or manual keyboard gets hidden or something.

回答1:

After struggling with that problem for quite some time, I've found a solution that seems to work without being too ugly. First, make sure that whatever ViewGroup (directly) contains your EditText has descendantFocusability set to "Before Descendants," focusable set to "true" and focusableInTouchMode set to "true." This will not be the ScrollView itself, but the layout inside where you have your various views. Next add an onTouchListener to your ScrollView that removes focus from the EditText whenever it is touched, like so:

ScrollView scroll = (ScrollView)findViewById(R.id.scrollView1);
scroll.setOnTouchListener(new OnTouchListener() {

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if (myEditText.hasFocus()) {
            myEditText.clearFocus();
        }
        return false;
    }
});

Tell me if that doesn't fix it. What should happen is that the Layout gets focus instead of the EditText, so no scrolling should happen.

回答2:

Just create an empty view at the top of linearlayout

<View android:layout_width="fill_parent" android:id="@+id/focus_view" android:layout_height="0dp" android:focusable="true" android:focusableInTouchMode="true"><requestFocus/></View>

Single line solves the problem

回答3:

I had the same problem. There's one trick that I'm using to deal with this problem:

public void onClick(View v) {
    button.requestFocusFromTouch(); //prevents from loosing focus and scrolling view down
    ....
}

回答4:

The issue is not on the java code, but on the manifest code.

In your AndroidManifest.xml add an attribute to the Activity:

        <activity android:name=".MyActivity" android:windowSoftInputMode="adjustPan"> </activity>

回答5:

By adding 2 parameters in:

android:focusable="true"
android:focusableInTouchMode="true"

In which Main layout is there.

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/layMain"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/background"
    android:focusable="true"
    android:focusableInTouchMode="true">

By this EditText will not be auto focused.

回答6:

Here is what I did

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" style="@style/measurementTableRowStyle"
    android:focusable="true" android:layout_height="fill_parent">
    <requestFocus></requestFocus>
    <LinearLayout android:id="@+id/linearLayout1"
        android:orientation="horizontal" android:layout_width="fill_parent"
        android:layout_height="wrap_content">
        <TextView android:id="@+id/desc_text" android:text="Value : "
            style="@style/attributeNameTextStyle" android:layout_width="wrap_content"
            android:focusable="true" android:layout_height="wrap_content">
            <requestFocus></requestFocus>
        </TextView>

        <TextView style="@style/attributeValueStyle" android:id="@+id/value_text"
            android:text="TextView" android:layout_width="wrap_content"
            android:layout_height="wrap_content"></TextView>
    </LinearLayout>

The reason is in such cases you have to make all other views focus-able inside the scrollview by an explicit android:focusable="true" and then <requestFocus></requestFocus> . This should work everytime IMO

回答7:

thomas88wp answer, https://stackoverflow.com/a/6486348/528746 worked for me. But I had two problems: 1. When scrolling, I wanted to hide the keyboard
2. I had lots of EditText views and didn't want to write it for each one of them
(I do getActivity() since I'm writing this inside a Fragment and not an activity)

    ScrollView scroll = (ScrollView)view.findViewById(R.id.layout_scroll);
    scroll.setOnTouchListener(new OnTouchListener() {

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            // Check if the view with focus is EditText
            if (getActivity().getCurrentFocus() instanceof EditText)
            {
                EditText ed = (EditText)getActivity().getCurrentFocus();
                if (ed.hasFocus()) {

                    // Hide the keyboard
                    InputMethodManager inputManager = (InputMethodManager)
                            getActivity().getSystemService(Context.INPUT_METHOD_SERVICE); 
                    inputManager.hideSoftInputFromWindow(getActivity().getCurrentFocus().getWindowToken(),
                            InputMethodManager.HIDE_NOT_ALWAYS);
                    // Clear the focus
                    ed.clearFocus();
                }
            }
            return false;
        }

    });

回答8:

My fix to this most horrific bug, (worth noting that this is pre API11 only where they modified the fling method not to be stupid).

The old fling method finds the next focus that it will get to.. which isn't really that helpful. Other versions of this class don't really work as they stop focus working when the user genuinely traverses the form from the keyboard.

public class NonFocusingScrollView extends ScrollView {

    private boolean mBlockRequestFocusOnFling = false;

    public NonFocusingScrollView(Context context) {
        super(context);
    }

    public NonFocusingScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

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

    @Override
    public ArrayList<View> getFocusables(int direction) {
        if(mBlockRequestFocusOnFling)
            return new ArrayList<View>();
        return super.getFocusables(direction);
    }

    @Override
    public void requestChildFocus(View child, View focused) {
        if(!mBlockRequestFocusOnFling)
        super.requestChildFocus(child, focused);
    }


    @Override
    public void fling(int velocityY) {
        mBlockRequestFocusOnFling = true;
        super.fling(velocityY);
        mBlockRequestFocusOnFling = false;
    }
}

回答9:

We can write a custom ScrollView and override the onScrollChanged method and clear the focus from the focused view and optionally hide the keyboard.

@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
    View v = getFocusedChild();
    if (v != null) {
        InputMethodManager imm = (InputMethodManager) getContext()
                .getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.hideSoftInputFromWindow(v.getWindowToken(), 0);
        v.clearFocus();
    }
    super.onScrollChanged(l, t, oldl, oldt);
}

回答10:

Another version of thomas88wp's code:

ScrollView scroll = (ScrollView)getActivity().findViewById(R.id.scrollView_addNewBill);
    scroll.setOnTouchListener(new OnTouchListener() {
        @Override
        public boolean onTouch(View arg0, MotionEvent arg1) {        
            View focussedView = getCurrentFocus(); 
            if( focussedView != null ) focussedView.clearFocus();
                
            return false;
    }
});

回答11:

I made a test project to experiment with the various solutions if anyone wants to play with it. https://github.com/marchold/EditText-ErrorPopup-Scroll-View

回答12:

Create a custom ScrollView (create a class and have it extend HorizontalScrollView) and make a getter setter for scrollable. Then override computeScrollDeltaToGetChildRectOnScreen.

How it works: Every time android has an edit text or something in focus that is off screen it calls method computeScrollDeltaToGetChildRectOnScreen to bring it into view. If you Override it and return 0 when it is disabled than it will not scroll...

So you will have A custom scroll view like this:

    public class TrackableHorizontalScrollView extends HorizontalScrollView {


    // true if we can scroll (not locked)
    // false if we cannot scroll (locked)
    private boolean mScrollable = true;

    public TrackableHorizontalScrollView(Context context) {
        super(context);
    }

    public TrackableHorizontalScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

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

    public void setScrollingEnabled(boolean enabled) {
        mScrollable = enabled;
    }

    public boolean isScrollable() {
        return mScrollable;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                // if we can scroll pass the event to the superclass
                if (mScrollable) return super.onTouchEvent(ev);
                // only continue to handle the touch event if scrolling enabled
                return mScrollable; // mScrollable is always false at this point
            default:
                return super.onTouchEvent(ev);
        }
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        // Don't do anything with intercepted touch events if
        // we are not scrollable
        if (!mScrollable) return false;
        else return super.onInterceptTouchEvent(ev);
    }

    @Override
    public void scrollTo(int x, int y){
        if (!mScrollable) return;
        super.scrollTo(x, y);
    }


    //Custom smooth scroll method since norm is final and cannot be overridden
    public final void smooothScrollToIfEnabled(int x, int y){
         if (!mScrollable) return;
         smoothScrollTo(x, y);
    }

    @Override
    protected int computeScrollDeltaToGetChildRectOnScreen(android.graphics.Rect rect){
        if (!mScrollable) return 0;
        return super.computeScrollDeltaToGetChildRectOnScreen(rect);
    }


}

You can use this inside your XML like this:

<com.your.package.ui.widget.TrackableHorizontalScrollView
            android:id="@+id/wi_et_credit_scroller"
            android:layout_toRightOf="@id/wi_et_credit_iv"
            android:layout_width="fill_parent"
            android:scrollbars="none"
            android:layout_height="wrap_content"
            android:paddingRight="5dp"
            android:layout_gravity="center_vertical">

<!--Whatever you have inside the scrollview-->

</com.your.package.ui.widget.TrackableHorizontalScrollView>

回答13:

I was having a similar problem and finally got it to work. My scroll view contains a series of customized buttons, followed by an EditText (which normally has focus, but I don't want it to be losing focus). Any time the buttons were clicked, the scroll view auto-scrolled to the focused EditText. Overriding public boolean requestChildRectangleOnScreen(final View child, final Rect rectangle, final boolean immediate) and always returning false (default behavior of a ViewGroup) did the trick. Hope it helps with your situation too.

回答14:

Only this code works for me:

public static void preventScrollViewFromScrollingToEdiText(ScrollView view) {
    view.setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
    view.setFocusable(true);
    view.setFocusableInTouchMode(true);
    view.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            v.requestFocusFromTouch();
            return false;
        }
    });
}

All credits go to this original answer.

回答15:

I often has this problem when my apps handle orientation change.

In that case I use the following kind of code:

@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    // to avoid the scrollview to scroll to this element automatically
    mEditTextSearch.setFocusable(false);
    // Get the saved scroll position
    final int scrolly = savedInstanceState.getInt("scrolly");
    mScrollView.post(new Runnable() {
        @Override
        public void run() {
            mScrollView.scrollTo(0, scrolly);
            // Restore the initial state of the EditText
            mEditTextSearch.setFocusable(true);
            mEditTextSearch.setFocusableInTouchMode(true);
            mEditTextSearch.setClickable(true);
        }
    });
    ...
}

回答16:

For me, it didn't work to override ScrollView onTouch. Also did not work android:descendantFocusability="beforeDescendants" android:focusableInTouchMode="true" This and another mentioned solutions only worked for the first time - only when EditText is not selected, but once you select it, scrollview autoscrolls again.

Because I was already written a code to hide a keyboard when touching other views, I just added two lines of code and it worked like a champ:

public static void setupUI(final Activity activity, final View view) {
    //view is the parent view in your layout
    OnTouchListener mTouchListener = new OnTouchListener() {
        public boolean onTouch(View v, MotionEvent event) {
            try {
                View vFocused = null;
                vFocused = activity.getCurrentFocus();

                if (vFocused != null) {
                    hideSoftKeyboard(activity, v);
                    if (vFocused instanceof EditText) {
                        vFocused.clearFocus();//this is the trick to avoid ScrollView autoscroll
                    }
                }
            } catch (Exception e) {
            }
            return false;
        }
    };

    // Set up touch listener for non-text box views to hide keyboard.
    if (!(view instanceof EditText) && !(view instanceof ViewGroup)) {
        view.setOnTouchListener(mTouchListener);
    }

    // If a layout container, iterate over children and seed recursion.
    if (view instanceof ViewGroup) {
        view.setOnTouchListener(mTouchListener);
        for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++) {
            View innerView = ((ViewGroup) view).getChildAt(i);
            setupUI(activity, innerView);
        }
    }
}
public static void hideSoftKeyboard(Context context, View v) {
    InputMethodManager inputMethodManager = (InputMethodManager) context
            .getSystemService(Activity.INPUT_METHOD_SERVICE);
    inputMethodManager.hideSoftInputFromWindow(v.getWindowToken(), 0);
}

also added this in root view:

android:descendantFocusability="beforeDescendants" android:focusableInTouchMode="true"

Maybe its not really nice solution, but its working.

回答17:

The best Solution is to add focus options for the child of your scrollview :

android:descendantFocusability="beforeDescendants"
android:focusable="true"
android:focusableInTouchMode="true"

Then your xml file will look like :

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/scrollView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginRight="50dp"
        android:descendantFocusability="beforeDescendants"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:orientation="vertical" >

        <EditText
            android:id="@+id/editText_one"
            android:layout_width="match_parent"
            android:layout_height="100dp"
            android:text="TestApp 1" />

        <EditText
            android:id="@+id/editText_two"
            android:layout_width="match_parent"
            android:layout_height="100dp"
            android:text="TestApp 2" />

       <EditText
            android:id="@+id/editText_three"
            android:layout_width="match_parent"
            android:layout_height="100dp"
            android:text="TestApp 3" />


    </LinearLayout>

</ScrollView>

回答18:

My solution is below, to trace the source code and override some function to stop auto scrolling by focused item.

You can check if the focusedView is TextView or its child is TextView, by using focusedView.findViewById(R.id.textview_id_you_defined) != null or focusedView instanceof TextView == true.

public class StopAutoFocusScrollView extends ScrollView {

    private View focusedView;
    private ScrollMonitorListener listener;

    public interface ScrollMonitorListener {
        public boolean enableScroll(View view);
    }
    public StopAutoFocusScrollView(Context context) {
        super(context);
    }

    public StopAutoFocusScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

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

    public void setScrollMonitorListener(ScrollMonitorListener listener) {
        this.listener = listener;
    }

    @Override
    public void requestChildFocus(View child, View focused) {
        focusedView = focused
        super.requestChildFocus(child, focused);
    }
    //flow : requestChildFocus -> scrollToChild -> scrollBy
    //Therefore, you can give listener to determine you want scroll to or not
    @Override
    public void scrollBy(int x, int y) {
        if (listener == null || listener.enableScroll(focusedView)) {
            super.scrollBy(x, y);
        }
    }
}

回答19:

I had a slightly different objection to this infuriating deficiency. Whenever I tapped one of a number of RadioButtons below the EditTexts, the scroll position jumped to accommodate what Android determined to be the visible and focused EditText.

All attempts to retain the current desired scroll position via a Runnable that issued ScrollView.scrollTo(x,y) were dutifully IGNORED by Android!

I share my solution in the hope that it may save someone else 8 (eight) wasted hours.

/* This interesting little 'hack' prevents unwanted scroll 'jump' occurring when
 user touches a RadioButton for example
[ Causes focus to change - but maybe this is a lesser evil! ] */
mScrollView.setOnTouchListener(new View.OnTouchListener() {
    @Override public boolean onTouch(View v, MotionEvent event) {
        if (event.getAction() != MotionEvent.ACTION_UP) 
            return false;

        mScrollView.clearFocus();
        return false;
    }
});

回答20:

Try this one :)

public class CustomHorizontalScrollView extends HorizontalScrollView {

    public CustomHorizontalScrollView(Context context) {
    super(context);
    }

    public CustomHorizontalScrollView(Context context, AttributeSet attrs) {
    super(context, attrs);
    }

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

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

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

    @Override
    public void scrollTo(int x, int y) {
    super.scrollTo(x, y);
    }


    //Custom smooth scroll method since norm is final and cannot be overridden
    public final void smooothScrollToIfEnabled(int x, int y) {
    smoothScrollTo(x, y);
    }

    @Override
    protected int computeScrollDeltaToGetChildRectOnScreen(android.graphics.Rect rect) {
/*  if (getContext() != null && getContext() instanceof Activity) {
        Activity activity = (Activity) getContext();
        if (!activity.isFinishing()) {
        View view = activity.getCurrentFocus();
        if (view != null) {
            if (view instanceof EditText) {
            return 0;
            }
        }
        }
    }
    return super.computeScrollDeltaToGetChildRectOnScreen(rect);

*/
return 0;
    }

}