Vertical ViewPager
The other answers here all seemed to have some problems with them. Even the recommended open source projects weren't merging recent pull requests with bug fixes. Then I found a VerticalViewPager from Google that they used some DeskClock app. I trust using Google's implementation a lot more than the other answers floating around here. (Google's version is similar to the current top-voted answer, but more thorough.)
Full Example
This example is almost exactly the same as my Basic ViewPager Example, with a few minor changes to make use of the VerticalViewPager class.
XML
Add the xml layouts for the main activity and for each page (fragment). Note that we use VerticalViewPager rather than the standard ViewPager. I'll include the code for that below.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.verticalviewpager.MainActivity">
<com.example.myapp.VerticalViewPager
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
fragment_one.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="@+id/textview"
android:textSize="30sp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true" />
</RelativeLayout>
Code
The code for the VerticalViewPager is not mine. It is just a stripped down version (without comments) from the Google source code. Check out that one for the most up to date version. The comments there are also helpful for understanding what is happening.
VerticalViewPager.java
import android.support.v4.view.ViewPager;
public class VerticalViewPager extends ViewPager {
public VerticalViewPager(Context context) {
this(context, null);
}
public VerticalViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
@Override
public boolean canScrollHorizontally(int direction) {
return false;
}
@Override
public boolean canScrollVertically(int direction) {
return super.canScrollHorizontally(direction);
}
private void init() {
setPageTransformer(true, new VerticalPageTransformer());
setOverScrollMode(View.OVER_SCROLL_NEVER);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
final boolean toIntercept = super.onInterceptTouchEvent(flipXY(ev));
flipXY(ev);
return toIntercept;
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
final boolean toHandle = super.onTouchEvent(flipXY(ev));
flipXY(ev);
return toHandle;
}
private MotionEvent flipXY(MotionEvent ev) {
final float width = getWidth();
final float height = getHeight();
final float x = (ev.getY() / height) * width;
final float y = (ev.getX() / width) * height;
ev.setLocation(x, y);
return ev;
}
private static final class VerticalPageTransformer implements ViewPager.PageTransformer {
@Override
public void transformPage(View view, float position) {
final int pageWidth = view.getWidth();
final int pageHeight = view.getHeight();
if (position < -1) {
view.setAlpha(0);
} else if (position <= 1) {
view.setAlpha(1);
view.setTranslationX(pageWidth * -position);
float yPosition = position * pageHeight;
view.setTranslationY(yPosition);
} else {
view.setAlpha(0);
}
}
}
}
MainActivity.java
I only swapped out VerticalViewPager
for ViewPager
.
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
public class MainActivity extends AppCompatActivity {
static final int NUMBER_OF_PAGES = 2;
MyAdapter mAdapter;
VerticalViewPager mPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mAdapter = new MyAdapter(getSupportFragmentManager());
mPager = findViewById(R.id.viewpager);
mPager.setAdapter(mAdapter);
}
public static class MyAdapter extends FragmentPagerAdapter {
public MyAdapter(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return NUMBER_OF_PAGES;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return FragmentOne.newInstance(0, Color.WHITE);
case 1:
// return a different Fragment class here
// if you want want a completely different layout
return FragmentOne.newInstance(1, Color.CYAN);
default:
return null;
}
}
}
public static class FragmentOne extends Fragment {
private static final String MY_NUM_KEY = "num";
private static final String MY_COLOR_KEY = "color";
private int mNum;
private int mColor;
// You can modify the parameters to pass in whatever you want
static FragmentOne newInstance(int num, int color) {
FragmentOne f = new FragmentOne();
Bundle args = new Bundle();
args.putInt(MY_NUM_KEY, num);
args.putInt(MY_COLOR_KEY, color);
f.setArguments(args);
return f;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mNum = getArguments() != null ? getArguments().getInt(MY_NUM_KEY) : 0;
mColor = getArguments() != null ? getArguments().getInt(MY_COLOR_KEY) : Color.BLACK;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_one, container, false);
v.setBackgroundColor(mColor);
TextView textView = v.findViewById(R.id.textview);
textView.setText("Page " + mNum);
return v;
}
}
}
Finished
You should be able to run the app and see the result in the animation above.
See also
- Basic ViewPager Example
- ViewPager with FragmentPagerAdapter