ScrollView滚动到顶部按钮点击android

Question

I have this strange "bug". A button that change its backgroundcolor inside a scrollview cause the scrollview to scroll up.

Layout

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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">

<ScrollView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <include layout="@layout/img_loading"  />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textIsSelectable="true"
            android:id="@+id/txt_read_story_title" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textIsSelectable="true"
            android:id="@+id/txt_read_story_author"
            />
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textIsSelectable="true"
            android:id="@+id/txt_read_story_content"
             />

        <include layout="@layout/inc_reactions_buttons" />
    </LinearLayout>
</ScrollView>

</android.support.constraint.ConstraintLayout>

Inside the inc_reactions_buttons.xml layout there are six buttons in an horizontal linearlayout.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:gravity="center_horizontal">


    <ImageView
        android:id="@+id/btn_funny"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_reaction_funny" />

 ...

</LinearLayout>

In the OnClickListener of this buttons, I change the enabled and the backgroundColor of them

mBtnLove.setEnabled(false);
mBtnLove.setBackground(Color.parseColor("#FF000000"))

The problem is that when a button is clicked, the scrollView scroll to the top. If I remove the setBackground, the scroll doesn't happens. I've already tried to use other types of view (ImageView, ImageButton) but the result is the same. Happens on API 25 and 26 (didn't test on earlier version)

Anyone knows the reason?

Thanks

Answer 1

Ok, found a solution.

As I stated in a comment above, the problem is caused by the TextViews having the attribute "textIsSelectable" set to True. It is not clear the reason (something calling the requestChildFocus), but I've found a workaround. In my buttons code, I set the textIsSelectable attribute to false, then change the backgroundColor of buttons, then reset the textIsSelectable to true.

Anyone have a better option?

Answer 2

Had same problem. In my case, simply setting

setKeyListener(null);
setFocusable(false);

for each EditText inside my ScrollView, fixed it.

Setting textIsSelectable to false is a solution too.