Develop Reference

View Pager with previous and next item smaller in size with infinite scroll

Want to create the view pager same as following UI, applied custom transformer but not working.
ViewPager.java
public class MyViewPager extends ViewPager implements ViewPager.PageTransformer {
public static final String TAG = "MyViewPager";
private float MAX_SCALE = 0.0f;
private int mPageMargin;
private boolean animationEnabled=true;
private boolean fadeEnabled=false;
private float fadeFactor=0.5f;
public MyViewPager(Context context) {
this(context, null);
}
public MyViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
// clipping should be off on the pager for its children so that they can scale out of bounds.
setClipChildren(false);
setClipToPadding(false);
// to avoid fade effect at the end of the page
setOverScrollMode(2);
setPageTransformer(false, this);
setOffscreenPageLimit(3);
mPageMargin = dp2px(context.getResources(), 50);
setPadding(mPageMargin, mPageMargin, mPageMargin, mPageMargin);
}
public int dp2px(Resources resource, int dp) {
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, resource.getDisplayMetrics());
}
public void setAnimationEnabled(boolean enable) {
this.animationEnabled = enable;
}
public void setFadeEnabled(boolean fadeEnabled) {
this.fadeEnabled = fadeEnabled;
}
public void setFadeFactor(float fadeFactor) {
this.fadeFactor = fadeFactor;
}
#Override
public void setPageMargin(int marginPixels) {
mPageMargin = marginPixels;
// setPadding(mPageMargin, mPageMargin, mPageMargin, mPageMargin);
}
#Override
public void transformPage(View page, float position) {
if (mPageMargin <= 0|| !animationEnabled)
return;
page.setPadding(mPageMargin / 3, mPageMargin / 3, mPageMargin / 3, mPageMargin / 3);
if (MAX_SCALE == 0.0f && position > 0.0f && position < 1.0f) {
MAX_SCALE = position;
}
position = position - MAX_SCALE;
float absolutePosition = Math.abs(position);
if (position <= -1.0f || position >= 1.0f) {
if(fadeEnabled)
page.setAlpha(fadeFactor);
// Page is not visible -- stop any running animations
} else if (position == 0.0f) {
// Page is selected -- reset any views if necessary
page.setScaleX((1 + MAX_SCALE));
page.setScaleY((1 + MAX_SCALE));
page.setAlpha(1);
} else {
page.setScaleX(1 + MAX_SCALE * (1 - absolutePosition));
page.setScaleY(1 + MAX_SCALE * (1 - absolutePosition));
if(fadeEnabled)
page.setAlpha( Math.max(fadeFactor, 1 - absolutePosition));
}
}
}

UPDATE - if you want to make current page zoom use below PageTransformer
import android.os.Bundle;
import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager2.widget.ViewPager2;
public class JavaActivity extends AppCompatActivity {
ViewPager2 myViewPager2;
MyAdapter MyAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_java);
myViewPager2 = findViewById(R.id.viewpager);
MyAdapter = new MyAdapter(this);
myViewPager2.setOrientation(ViewPager2.ORIENTATION_HORIZONTAL);
myViewPager2.setAdapter(MyAdapter);
myViewPager2.setOffscreenPageLimit(3);
float pageMargin = getResources().getDimensionPixelOffset(R.dimen.pageMargin);
float pageOffset = getResources().getDimensionPixelOffset(R.dimen.offset);
myViewPager2.setPageTransformer((page, position) -> {
float myOffset = position * -(2 * pageOffset + pageMargin);
if (position < -1) {
page.setTranslationX(-myOffset);
} else if (position <= 1) {
float scaleFactor = Math.max(0.7f, 1 - Math.abs(position - 0.14285715f));
page.setTranslationX(myOffset);
page.setScaleY(scaleFactor);
page.setAlpha(scaleFactor);
} else {
page.setAlpha(0);
page.setTranslationX(myOffset);
}
});
}
}
OUTPUT
NOTE: you can download complete code from my GitHub repositories
Try this way
JavaActivity
import android.os.Bundle;
import android.view.View;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.view.ViewCompat;
import androidx.viewpager2.widget.ViewPager2;
public class JavaActivity extends AppCompatActivity {
ViewPager2 myViewPager2;
MyAdapter MyAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_java);
myViewPager2 = findViewById(R.id.viewpager);
MyAdapter = new MyAdapter(this);
myViewPager2.setOrientation(ViewPager2.ORIENTATION_HORIZONTAL);
myViewPager2.setAdapter(MyAdapter);
myViewPager2.setOffscreenPageLimit(3);
float pageMargin= getResources().getDimensionPixelOffset(R.dimen.pageMargin);
float pageOffset = getResources().getDimensionPixelOffset(R.dimen.offset);
myViewPager2.setPageTransformer(new ViewPager2.PageTransformer() {
#Override
public void transformPage(#NonNull View page, float position) {
float myOffset = position * -(2 * pageOffset + pageMargin);
if (myViewPager2.getOrientation() == ViewPager2.ORIENTATION_HORIZONTAL) {
if (ViewCompat.getLayoutDirection(myViewPager2) == ViewCompat.LAYOUT_DIRECTION_RTL) {
page.setTranslationX(-myOffset);
} else {
page.setTranslationX(myOffset);
}
} else {
page.setTranslationY(myOffset);
}
}
});
}
}
activity_java layout file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
android:orientation="vertical"
tools:context=".JavaActivity">
<androidx.viewpager2.widget.ViewPager2
android:id="#+id/viewpager"
android:clipToPadding="false"
android:clipChildren="false"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
>
MyAdapter
import android.content.Context;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private Context context;
public MyAdapter(Context context) {
this.context = context;
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.row_item, parent, false);
return new MyViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull MyViewHolder holder, int position) {
holder.tvName.setText(String.format("Row number%d", position));
if (position % 2 ==0){
holder.imgBanner.setBackgroundColor(Color.RED);
}else {
holder.imgBanner.setBackgroundColor(Color.GREEN);
}
}
#Override
public int getItemCount() {
return 15;
}
public class MyViewHolder extends RecyclerView.ViewHolder {
TextView tvName;
ImageView imgBanner;
public MyViewHolder(#NonNull View itemView) {
super(itemView);
tvName = itemView.findViewById(R.id.tvName);
imgBanner = itemView.findViewById(R.id.imgBanner);
}
}
}
row_item layout
<?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_marginLeft="#dimen/pageMarginAndOffset"
android:layout_marginRight="#dimen/pageMarginAndOffset"
android:layout_height="match_parent"
android:orientation="vertical">
<ImageView
android:id="#+id/imgBanner"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorAccent"
android:contentDescription="#string/app_name"/>
<TextView
android:id="#+id/tvName"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:layout_centerInParent="true"
android:textColor="#android:color/white"
android:textSize="20sp"
android:textStyle="bold"
tools:text="Hello"/>
</RelativeLayout>
OUTPUT

Using ViewPager2 (that has RecyclerView in it).
vp2 is instance of ViewPager2
This worked for me:
RecyclerView rv = (RecyclerView) vp2.getChildAt(0);
rv.setPadding(80, 0, 80, 0);
rv.setClipToPadding(false);
I used FragmentStateAdapter for it and overriding getItemId() and containsItem() for add/remove fragments.
result is here:

You can make use of clipToPadding and programmatically adding the pageMargin and padding to your viewpager.
Try something like this-
viewpager.setClipToPadding(false);
viewpager.setPadding(40, 0, 70, 0);
viewpager.setPageMargin(20);

VideoView disappearing while scrolling/swiping in VerticalViewPager

I am having an issue with VideoView when using with VerticalViewPager.
When I scroll/swipe the ViewPager the VideoView becomes black. Actually here VideoView is getting disappeared the black color is the background of the ViewPager.
I don't have this issue when using horizontal ViewPager even with current custom VerticalViewpager set to horizontal.
When I scroll, VideoView disappears and when I lift my finger from screen VideoView appears back again.
I have tried many VerticalViewpager libraries and almost all of them have this same issue.
Have anyone faced this issue before? How to fix this?
These are the screenshots:
VideoView when not swiping:
VideoView when swiping vertically:
Here is my code
VerticalViewpager.java
import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class VerticalViewpager extends ViewPager {
public VerticalViewpager(Context context) {
super(context);
init();
}
public VerticalViewpager(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
private void init() {
// The majority of the magic happens here
setPageTransformer(true, new VerticalPageTransformer());
// The easiest way to get rid of the overscroll drawing that happens on the left and right
setOverScrollMode(OVER_SCROLL_NEVER);
}
private class VerticalPageTransformer implements ViewPager.PageTransformer {
#Override
public void transformPage(View view, float position) {
if (position < -1) { // [-Infinity,-1)
// This page is way off-screen to the left.
view.setAlpha(0);
} else if (position <= 1) { // [-1,1]
view.setAlpha(1);
// Counteract the default slide transition
view.setTranslationX(view.getWidth() * -position);
//set Y position to swipe in from top
float yPosition = position * view.getHeight();
view.setTranslationY(yPosition);
} else { // (1,+Infinity]
// This page is way off-screen to the right.
view.setAlpha(0);
}
}
}
/**
* Swaps the X and Y coordinates of your touch event.
*/
private MotionEvent swapXY(MotionEvent ev) {
float width = getWidth();
float height = getHeight();
float newX = (ev.getY() / height) * width;
float newY = (ev.getX() / width) * height;
ev.setLocation(newX, newY);
return ev;
}
#Override
public boolean onInterceptTouchEvent(MotionEvent ev){
boolean intercepted = super.onInterceptTouchEvent(swapXY(ev));
swapXY(ev); // return touch coordinates to original reference frame for any child views
return intercepted;
}
#Override
public boolean onTouchEvent(MotionEvent ev) {
return super.onTouchEvent(swapXY(ev));
}
}
MainActivity.java
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v7.app.AppCompatActivity;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
MyPagerAdapter adapterViewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
VerticalViewpager vpPager = (VerticalViewpager) findViewById(R.id.vpPAger);
adapterViewPager = new MyPagerAdapter(getSupportFragmentManager());
vpPager.setAdapter(adapterViewPager);
for (int i = 0; i < 2; i++) {
adapterViewPager.addFragment(FragmentWithOneImage.newInstance("Frag "+ i,R.drawable.jackie));
}
vpPager.setAdapter(adapterViewPager);
}
public static class MyPagerAdapter extends FragmentStatePagerAdapter {
private final List<Fragment> mFragments = new ArrayList<>();
public MyPagerAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment) {
mFragments.add(fragment);
}
#Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
#Override
public int getCount() {
return mFragments.size();
}
#Override
public float getPageWidth(int position) {
return super.getPageWidth(position);
}
}
}
FragmentWithOneImage.java
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.VideoView;
public class FragmentWithOneImage extends Fragment {
private String title;
private int image;
public static FragmentWithOneImage newInstance(String title, int resImage) {
FragmentWithOneImage fragment = new FragmentWithOneImage();
Bundle args = new Bundle();
args.putInt("image", resImage);
args.putString("title", title);
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
image = getArguments().getInt("image", 0);
title = getArguments().getString("title");
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_one_img, container, false);
ImageView imageView = (ImageView) view.findViewById(R.id.imgMain);
imageView.setImageResource(image);
Uri uri = Uri.parse("http://abhiandroid-8fb4.kxcdn.com/ui/wp-content/uploads/2016/04/videoviewtestingvideo.mp4");
VideoView simpleVideoView = (VideoView) view.findViewById(R.id.simpleVideoView); // initiate a video view
simpleVideoView.setVideoURI(uri);
simpleVideoView.start();
return view;
}
#Override
public void onResume() {
super.onResume();
}
}
activiy_main.xml
<?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="match_parent"
android:orientation="vertical">
<com.example.sudheeshm.verticalviewpager.VerticalViewpager
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/vpPAger"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:swipe_orientation="vertical"
android:background="#android:color/black"/>
</LinearLayout>
fragment_one_img.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/white"
>
<VideoView
android:id="#+id/simpleVideoView"
android:layout_width="match_parent"
android:layout_height="300dp" />
<ImageView
android:layout_below="#+id/simpleVideoView"
android:id="#+id/imgMain"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
attrs.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="VerticalViewpager" >
<attr name="swipe_orientation" format="enum" >
<enum name="horizontal" value="0" />
<enum name="vertical" value="1" />
</attr>
</declare-styleable>
</resources>

It has to do with VideoView being based on SurfaceView and this view is not optimized for tranlations (scrolling in a ViewPager). Check out these answers related to VideoViews in a ViewPager at these following links: post 1, 2.
Maybe you can find a solution to your issue.

Android : ViewPager with a dynamic height within a ScrollView

I have a ScrollView which hosts a ViewPager which hosts Fragments of dynamic height. Since a ScrollView and ViewPager don't go well together due to the scroll handling, I used one of the custom solution from here. But I am currently getting really abnormal results. The first fragment in the ViewPager always gets a height of 0. Also sometimes the fragments don't show their content but when I scroll back and forth and come back to that fragment, content might show up.
Some code for you to look at :
The custom ViewPager :
import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
/**
* Created by Narayan Acharya on 12/07/2016.
*/
public class DynamicHeightWrappingViewPager extends ViewPager {
private View mCurrentView;
public DynamicHeightWrappingViewPager(Context context) {
super(context);
}
public DynamicHeightWrappingViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mCurrentView == null) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
return;
}
int height = 0;
mCurrentView.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
int h = mCurrentView.getMeasuredHeight();
if (h > height) height = h;
heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
Log.d("ViewPager Measure", h + ":" + heightMeasureSpec);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
public void measureCurrentView(View currentView) {
mCurrentView = currentView;
requestLayout();
}
}
The custom ScrollView :
import android.content.Context;
import android.util.AttributeSet;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.widget.ScrollView;
/**
* Created by Narayan Acharya on 12/07/2016.
*/
public class ChildrenHeightAdaptingScrollView extends ScrollView {
private GestureDetector mGestureDetector;
public ChildrenHeightAdaptingScrollView(Context context, AttributeSet attrs) {
super(context, attrs);
mGestureDetector = new GestureDetector(context, new YScrollDetector());
setFadingEdgeLength(0);
}
#Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
return super.onInterceptTouchEvent(ev)
&& mGestureDetector.onTouchEvent(ev);
}
// Return false if we're scrolling in the x direction
class YScrollDetector extends GestureDetector.SimpleOnGestureListener {
#Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
return (Math.abs(distanceY) > Math.abs(distanceX));
}
}
}
The PagerAdapter :
import android.app.Fragment;
import android.app.FragmentManager;
import android.support.v13.app.FragmentPagerAdapter;
import android.util.Log;
import android.view.ViewGroup;
/.. Some more project specific imports here../
/**
* Created by Narayan Acharya on 22/06/2016.
*/
public class EventsPagerAdapter extends FragmentPagerAdapter {
private Event event;
private int PAGE_COUNT = 2;
private int mCurrentPosition = -1;
private String tabTitles[] = new String[]{"INFO", "FAQs"};
public EventsPagerAdapter(FragmentManager fm, Event event) {
super(fm);
this.event = event;
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return EventInfoFragment.getInstance(event);
case 1:
return EventFAQsFragment.getInstance(event);
default:
return null;
}
}
#Override
public int getCount() {
return PAGE_COUNT;
}
#Override
public CharSequence getPageTitle(int position) {
// Generate title based on item position
return tabTitles[position];
}
#Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
super.setPrimaryItem(container, position, object);
if (position != mCurrentPosition) {
Fragment fragment = (Fragment) object;
DynamicHeightWrappingViewPager pager = (DynamicHeightWrappingViewPager) container;
if (fragment != null && fragment.getView() != null) {
mCurrentPosition = position;
pager.measureCurrentView(fragment.getView());
Log.d("Requested Measure for", position + " " + fragment.getClass().getSimpleName());
}
}
}
}
As per my observations, the only difference I could spot in the code from the link I mentioned above and the one I am using is that the link uses FragmentPagerAdapter from support library v4 while I am using from the v13(Cannot change this to v4, due to some other restrictions). What are the major differences between the two versions of support library for how I am using it?

This might seem like really stupid and I am not sure why this works exactly! If anyone knows why, please do answer.
The problem with the ViewPager collapsing was that it simply contained a WebView in each Fragment. I toiled hard trying to find solutions and writing more custom ViewPagers and ScrollViews. Just when I was about to give up I wrapped the WebView in a LinearLayout and the Fragment at position 0 did not collapse. It works smoothly now.
So if anyone is getting blank pages while trying this or similar solutions please try to wrap it in a LinearLayout or something.
Hope this helps someone!

Photo album like card flip using ViewPager?

How can i implement same as the UI and code found in GitHub by using latest tools like ViewPager. the code founded hasn't developed with latest tools.It seems little difficult UI for me.
Any suggestion ?

Try like this
<?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">
<com.example.pagercontainer.PagerContainer
android:id="#+id/pager_container"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#CCC">
<android.support.v4.view.ViewPager
android:layout_width="150dp"
android:layout_height="100dp"
android:layout_gravity="center_horizontal" />
</com.example.pagercontainer.PagerContainer>
</RelativeLayout>
PagerActivity.java
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
/**
* PagerActivity: A Sample Activity for PagerContainer
*/
public class PagerActivity extends Activity {
PagerContainer mContainer;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mContainer = (PagerContainer) findViewById(R.id.pager_container);
ViewPager pager = mContainer.getViewPager();
PagerAdapter adapter = new MyPagerAdapter();
pager.setAdapter(adapter);
//Necessary or the pager will only have one extra page to show
// make this at least however many pages you can see
pager.setOffscreenPageLimit(adapter.getCount());
//A little space between pages
pager.setPageMargin(15);
//If hardware acceleration is enabled, you should also remove
// clipping on the pager for its children.
pager.setClipChildren(false);
}
//Nothing special about this adapter, just throwing up colored views for demo
private class MyPagerAdapter extends PagerAdapter {
#Override
public Object instantiateItem(ViewGroup container, int position) {
TextView view = new TextView(PagerActivity.this);
view.setText("Item "+position);
view.setGravity(Gravity.CENTER);
view.setBackgroundColor(Color.argb(255, position * 50, position * 10, position * 50));
container.addView(view);
return view;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((View)object);
}
#Override
public int getCount() {
return 5;
}
#Override
public boolean isViewFromObject(View view, Object object) {
return (view == object);
}
}
}
PagerContainer .java
import android.content.Context;
import android.graphics.Point;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.FrameLayout;
/**
* PagerContainer: A layout that displays a ViewPager with its children that are outside
* the typical pager bounds.
*/
public class PagerContainer extends FrameLayout implements ViewPager.OnPageChangeListener {
private ViewPager mPager;
boolean mNeedsRedraw = false;
public PagerContainer(Context context) {
super(context);
init();
}
public PagerContainer(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public PagerContainer(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
//Disable clipping of children so non-selected pages are visible
setClipChildren(false);
//Child clipping doesn't work with hardware acceleration in Android 3.x/4.x
//You need to set this value here if using hardware acceleration in an
// application targeted at these releases.
setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}
#Override
protected void onFinishInflate() {
try {
mPager = (ViewPager) getChildAt(0);
mPager.setOnPageChangeListener(this);
} catch (Exception e) {
throw new IllegalStateException("The root child of PagerContainer must be a ViewPager");
}
}
public ViewPager getViewPager() {
return mPager;
}
private Point mCenter = new Point();
private Point mInitialTouch = new Point();
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
mCenter.x = w / 2;
mCenter.y = h / 2;
}
#Override
public boolean onTouchEvent(MotionEvent ev) {
//We capture any touches not already handled by the ViewPager
// to implement scrolling from a touch outside the pager bounds.
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
mInitialTouch.x = (int)ev.getX();
mInitialTouch.y = (int)ev.getY();
default:
ev.offsetLocation(mCenter.x - mInitialTouch.x, mCenter.y - mInitialTouch.y);
break;
}
return mPager.dispatchTouchEvent(ev);
}
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
//Force the container to redraw on scrolling.
//Without this the outer pages render initially and then stay static
if (mNeedsRedraw) invalidate();
}
#Override
public void onPageSelected(int position) { }
#Override
public void onPageScrollStateChanged(int state) {
mNeedsRedraw = (state != ViewPager.SCROLL_STATE_IDLE);
}
}
See this

android - custom view has width and height of 0

I'm trying to create a custom view with two TextViews inside a vertical LinearLayout, but am totally confused as to how it all works.
Currently nothing is appearing as I my onDraw method isn't being called. I think this is due to the fact that my view (the LinearLayout?) has a width and height of both 0.
I think I should be overwriting my onMeasure, but after trying setMeasuredDimension(100,100) this still isn't working.
I am trying to inflate an xml inside the view and use the two TextViews in that.
An explanation would also be great so I can hopefully get my head around how this all works.
Thanks
size_button.xml
<?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="vertical" >
<TextView
android:id="#+id/sizeButtonSizeText"
android:layout_width="wrap_content"
android:layout_height="match_parent" />
<TextView
android:id="#+id/sizeButtonSlugText"
android:layout_width="wrap_content"
android:layout_height="match_parent" />
</LinearLayout>
SizeButton.java
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View.MeasureSpec;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.nap.library.NapApplication;
import com.nap.library.R;
public class SizeButton extends LinearLayout {
private TextView mSize;
private TextView mSlug;
private String mSizeText;
private String mSlugText;
private Paint mPaint;
private boolean mSoldOut;
private Context mContext;
/*
public SizeButton(Context context) {
super(context);
setup();
}
public SizeButton(Context context, AttributeSet attrs) {
super(context, attrs);
setup();
}
*/
public SizeButton(Context context, String size, String slug) {
super(context);
mContext = context;
mSizeText = size;
mSlugText = slug;
setup();
}
public void setSoldOut(){
this.mSoldOut = true;
}
public boolean isSoldOut(){
return mSoldOut;
}
public void setSizeText(String size){
mSize.setText(size);
}
public void setSlugText(String slug){
mSlug.setText(slug);
}
public void setup(){
mPaint = new Paint();
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
LinearLayout buttonLayout = (LinearLayout) inflater.inflate(R.layout.size_button, null);
mSize = (TextView) buttonLayout.findViewById(R.id.sizeButtonSizeText);
mSize.setGravity(Gravity.CENTER);
mSize.setTextColor(Color.BLACK);
mSize.setText(mSizeText);
mSize.setTypeface(NapApplication.mPorter);
mSize.setWidth(10);
mSlug = (TextView) buttonLayout.findViewById(R.id.sizeButtonSlugText);
mSlug.setGravity(Gravity.CENTER);
mSlug.setTextColor(Color.BLACK);
mSlug.setText(mSlugText);
mSlug.setTypeface(NapApplication.mPorter);
invalidate();
requestLayout();
LinearLayout.LayoutParams layoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT);
mSize.setLayoutParams(layoutParams);
mSlug.setLayoutParams(layoutParams);
Log.i("button","in setup");
Log.i("button","width = "+this.getWidth()+" height = "+this.getHeight());
Log.i("button","width = "+mSize.getWidth()+" sizeheight = "+mSize.getHeight());
Log.i("button","width = "+mSlug.getWidth()+" slugheight = "+mSlug.getHeight());
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
Log.i("button","in onMeasure");
setMeasuredDimension(100,100);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Log.i("button","in ondraw");
}
}
ProductFragment.java - where the button is added to the fragment
for (int i = 0; i < mItem.getSizes().length; i++) {
final SizeButton sizeButton = new SizeButton(getActivity(),mItem.getSizes()[i],"hello");
// Each size button has a sku set as its tag
sizeButton.setTag(mItem.getSkus()[i]);
sizeButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
if(mItem.getSizes().length > 1) {
boolean selected = !sizeButton.isSelected();
if (selected) {
mCurrentSku = (String) v.getTag();
} else {
mCurrentSku = null;
}
}
configureButtons();
}
});
Log.e("button","Adding button to view");
mSizesWrapper.addView(sizeButton);
}

As your are extending a ViewGroup, you should override dispatchDraw(), not onDraw()