Is it possible to have a ViewPager inside of a ScrollView?
I'm trying to use a ViewPager
inside of a ScrollView
, but the ViewPager
does not appear. If I remove the ScrollView
the ViewPager
appears fine.
I've created a simple test project with the following:
main.xml layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<android.support.v4.view.ViewPager
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/viewpager" />
</ScrollView>
</LinearLayout>
Activity class:
public class ScrollViewWithViewPagerActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ViewPager vp = (ViewPager) findViewById(R.id.viewpager);
vp.setAdapter(new MyPagerAdapter(this));
}
}
class MyPagerAdapter extends PagerAdapter {
private Context ctx;
public MyPagerAdapter(Context context) {
ctx = context;
}
@Override
public int getCount() {
return 2;
}
@Override
public Object instantiateItem(View collection, int position) {
TextView tv = new TextView(ctx);
tv.setTextSize(50);
tv.setText开发者_运维知识库Color(Color.WHITE);
tv.setText("SMILE DUDE, SMILE DUDE, SMILE DUDE, SMILE DUDE, SMILE DUDE, " +
"SMILE DUDE, SMILE DUDE, SMILE DUDE, SMILE DUDE, SMILE DUDE, " +
"SMILE DUDE, SMILE DUDE, SMILE DUDE, SMILE DUDE, SMILE DUDE, " +
"SMILE DUDE, SMILE DUDE, SMILE DUDE");
((ViewPager) collection).addView(tv);
return tv;
}
@Override
public void destroyItem(View collection, int position, Object view) {
((ViewPager) collection).removeView((View) view);
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
@Override
public Parcelable saveState() {
return null;
}
@Override
public void restoreState(Parcelable arg0, ClassLoader arg1) {
}
@Override
public void startUpdate(View arg0) {
}
@Override
public void finishUpdate(View arg0) {
}
}
Thanks for your time.
I've figured it out;
I needed to add android:fillViewport="true"
to the ScrollView element.
Yes it is possible to have viewpager inside scrollview.
Use below code and you will achieve your goal, i have done the same in my code as well.
public class WrapContentHeightViewPager extends ViewPager {
public WrapContentHeightViewPager(Context context) {
super(context);
}
public WrapContentHeightViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int height = 0;
for (int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
child.measure(widthMeasureSpec, View.MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
int h = child.getMeasuredHeight();
if (h > height) height = h;
}
heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
@Override
public boolean onTouch(View v, MotionEvent event) {
int dragthreshold = 30;
int downX = 0;
int downY = 0;
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
downX = (int) event.getRawX();
downY = (int) event.getRawY();
break;
case MotionEvent.ACTION_MOVE:
int distanceX = Math.abs((int) event.getRawX() - downX);
int distanceY = Math.abs((int) event.getRawY() - downY);
if (distanceY > distanceX && distanceY > dragthreshold) {
mViewPager.getParent().requestDisallowInterceptTouchEvent(false);
mScrollView.getParent().requestDisallowInterceptTouchEvent(true);
} else if (distanceX > distanceY && distanceX > dragthreshold) {
mViewPager.getParent().requestDisallowInterceptTouchEvent(true);
mScrollView.getParent().requestDisallowInterceptTouchEvent(false);
}
break;
case MotionEvent.ACTION_UP:
mScrollView.getParent().requestDisallowInterceptTouchEvent(false);
mViewPager.getParent().requestDisallowInterceptTouchEvent(false);
break;
}
return false;
}
Hope this aids someone in resolving scroll issues with nested ViewPager within a ScrollView.
This solution worked for me, with dynamic content.
http://www.henning.ms/2013/09/09/viewpager-that-simply-dont-measure-up/
In the xml ScrollView
put android:fillViewport=true
and android:layout_height=wrap_content
And in custom ViewPager too put android:layout_height=wrap_content
In case someone is having the same problem, when I use the class below it works fine.
class CustomWrapContentViewPager(cont: Context, attr: AttributeSet?) : ViewPager(cont,attr) {
override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec)
var height = 0
for (i in 0 until childCount) {
val child: View = getChildAt(i)
child.measure(
widthMeasureSpec,
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED)
)
val h: Int = child.measuredHeight
if (h > height) height = h
}
val heightMeasure = MeasureSpec.makeMeasureSpec(
height,
MeasureSpec.EXACTLY
)
super.onMeasure(widthMeasureSpec, heightMeasure)
}
}
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