Develop Reference

How can I implement a rotative banner for my Android app?

On my login activity I would like to have a banner (3 actually) which would switch by certain time. Just like news on a website. With an arrow to pass to the next one, but mainly that passes automatically.
An example of what I want, these images on Tinder login screen switch when I swipe or just wait:
How do I do something like this on Android? Is there a way to do it natively? or at least is there a external resource for that?

Try this code,
public class TestActivity extends AppCompatActivity {
int images[] = {R.drawable.ic_earth, R.drawable.oval_btn,
R.drawable.ic_group_black_24dp, R.drawable.ic_earth};
ImagePagerAdapter myAdapter;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.tests);
ViewPager viewPager = findViewById(R.id.viewPager);
myAdapter = new ImagePagerAdapter(TestActivity.this, images);
viewPager.setAdapter(myCustomPagerAdapter);
setupViewPager(viewPager);
}
int currentPage = 0;
Timer timer;
final long DELAY_MS = 500;
final long PERIOD_MS = 3000;
int NUM_PAGES = 4;
private void setupViewPager(final ViewPager viewPager) {
final Handler handler = new Handler();
final Runnable Update = new Runnable() {
public void run() {
if (currentPage == NUM_PAGES) {
currentPage = 0;
}
viewPager.setCurrentItem(currentPage++, true);
}
};
timer = new Timer(); // This will create a new Thread
timer .schedule(new TimerTask() { // task to be scheduled
#Override
public void run() {
handler.post(Update);
}
}, DELAY_MS, PERIOD_MS);
}
public class ImagePagerAdapter extends PagerAdapter {
Context context;
int images[];
LayoutInflater layoutInflater;
public ImagePagerAdapter(Context context, int images[]) {
this.context = context;
this.images = images;
layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
#Override
public int getCount() {
return images.length;
}
#Override
public boolean isViewFromObject(View view, Object object) {
return view == ((LinearLayout) object);
}
#Override
public Object instantiateItem(ViewGroup container, final int position) {
View itemView = layoutInflater.inflate(R.layout.item, container, false);
ImageView imageView = (ImageView) itemView.findViewById(R.id.imageView);
imageView.setImageResource(images[position]);
container.addView(itemView);
//listening to image click
imageView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
}
});
return itemView;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((LinearLayout) object);
}
}
}

Unable to set automatically image slide in android Fragment

In my app I want an image slider.I already do that with view pager but I want image change automatically in every 2seconds. I am unable to do that.
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_about, container,false);
viewPager = (ViewPager) rootView.findViewById(R.id.viewPager);
adapter = new CustomSwipeAdapter(this.getActivity());
viewPager.setAdapter(adapter);
indicator = (CircleIndicator) rootView.findViewById(R.id.indicator);
indicator.setViewPager(viewPager);
return rootView;
}
this is my fragment class.
public class CustomSwipeAdapter extends PagerAdapter {
private int[] image_resource = {R.drawable.sample_1, R.drawable.sample_2};
private Context ctx;
private LayoutInflater layoutInflater;
public CustomSwipeAdapter(Context ctx) {
this.ctx = ctx;
}
#Override
public int getCount() {
return image_resource.length;
}
#Override
public boolean isViewFromObject(#NonNull View view, #NonNull Object object) {
return (view == object);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
layoutInflater = (LayoutInflater) ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View item_view = layoutInflater.inflate(R.layout.image_swipe_layout, container, false);
ImageView imageview = (ImageView) item_view.findViewById(R.id.image_view);
imageview.setImageResource(image_resource[position]);
container.addView(item_view);
return item_view;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((LinearLayout)object);
}
}
this is my adapter class.I want that image change automatically.Please help me.Thanks.

A code I had written a really long time ago which does something similar, maybe this can help you.
final Handler handler = new Handler();
final Runnable update = () -> {
if (currentPage == list.size()) {
currentPage = 0;
}
pager.setCurrentItem(currentPage++, true);
};
Timer timer = new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
handler.post(update);
}
}, 2500, 2500);
#Override
protected void onDestroy() {
super.onDestroy();
timer.cancel();
}
So you set a timer which gets called after a certain interval of time (~2.5 seconds here) and when it does, you check if the current page of the adapter has reached the end then reset it back to 0 else increment it.

Auto slider images using ViewPager

I'm trying to replace colors by images from Drawable in this code.
I found this tutorial on how we can make an auto images slider by using viewpager on Android Studio, but this code is to switch colors images how can I replace this colors by images?
Here is my SliderAdapter.java
public class SliderAdapter extends PagerAdapter {
private Context context;
private List<Integer> color;
private List<String> colorName;
public SliderAdapter(Context context, List<Integer> color, List<String> colorName) {
this.context = context;
this.color = color;
this.colorName = colorName;
}
#Override
public int getCount() {
return color.size();
}
#Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.item_slider, null);
TextView textView = (TextView) view.findViewById(R.id.textView);
LinearLayout linearLayout = (LinearLayout)
view.findViewById(R.id.linearLayout);
textView.setText(colorName.get(position));
linearLayout.setBackgroundColor(color.get(position));
ViewPager viewPager = (ViewPager) container;
viewPager.addView(view, 0);
return view;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
ViewPager viewPager = (ViewPager) container;
View view = (View) object;
viewPager.removeView(view);
}
}
here is my MainActivity
public class MainActivity extends AppCompatActivity {
ViewPager viewPager;
TabLayout indicator;
List<Integer> color;
List<String> colorName;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
viewPager=(ViewPager)findViewById(R.layout.viewPager);
indicator=(TabLayout)findViewById(R.layout.indicator);
color = new ArrayList<>();
color.add(Color.RED);
color.add(Color.GREEN);
color.add(Color.BLUE);
colorName = new ArrayList<>();
colorName.add("RED");
colorName.add("GREEN");
colorName.add("BLUE");
viewPager.setAdapter(new SliderAdapterDemo(this, color, colorName));
indicator.setupWithViewPager(viewPager, true);
Timer timer = new Timer();
timer.scheduleAtFixedRate(new SliderTimer(), 4000, 6000);
}
private class SliderTimer extends TimerTask {
#Override
public void run() {
MainActivity.this.runOnUiThread(new Runnable() {
#Override
public void run() {
if (viewPager.getCurrentItem() < color.size() - 1) {
viewPager.setCurrentItem(viewPager.getCurrentItem() + 1);
} else {
viewPager.setCurrentItem(0);
}
}
});
}
}
}

android ViewPager starts at a wrong random location after reload

I am writing a simple view pager test app that loads a bunch of data from a website and creates pages to display them.
For the most part the displaying is pretty much all works. However, it falls apart when I load a new set of data to display. When I get a new set, it loads all the data perfectly well however, instead of starting from view 0 it starts at a random location. It could start at the end or somewhere in the middle.
I want all the data to load from page 1, like a book. If you load a new book the book should start from page 1 not a random page.
Reloading calls
I've tried using GotCampDetails() which sets the local variable in the class.
viewPager.setCurrentItem(0);
in my fragment but it doesn't work. Also called notifydatasetchanged() on my adapter, still didn't work.
What am I missing?
public class ViewPagerFragment extends Fragment implements WebReadResultsListener {
private ArrayList<HashMap<String, String>> campDetails;
CustomPagerAdapter adapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.camp_viewpager, container, false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
if (campDetails != null && ! campDetails.isEmpty()) {
ViewPager viewPager = (ViewPager) view.findViewById(R.id.viewpager);
adapter = new CustomPagerAdapter(getActivity(), campDetails, viewPager);
viewPager.setAdapter(adapter);
viewPager.setPageTransformer(true, new ZoomOutPageTransformer());
}
}
#Override
public boolean GotCampDetails(ArrayList<HashMap<String, String>> campDetails) {
this.campDetails = campDetails;
return true;
}
#Override
public boolean GotCampList(ArrayList<HashMap<String, String>> campDetails) {
return false;
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
getFragmentManager().putFragment(outState,"fragmentInstanceSaved",getFragmentManager().findFragmentById(R.id.content));
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Handle orientation changes here
}
}
Adapter:
public class CustomPagerAdapter extends PagerAdapter implements ColorChangeListener {
private ArrayList<HashMap<String, String>> campDetails;
private ViewGroup collection;
private Context mContext;
private boolean isRunning = false;
private ColorChangeListener colorChangeListener;
private int color= pink;
private int currentposition;
private ViewPager viewPager;
public CustomPagerAdapter(Context context, final ArrayList<HashMap<String, String>> campDetails, ViewPager viewPager) {
this.campDetails=campDetails;
this.mContext = context;
this.viewPager = viewPager;
colorChangeListener = (ColorChangeListener) mContext;
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageSelected(int pos) {
currentposition = pos;
if (campDetails.get(currentposition).get("color").equals("green")) {
color = green;
} else {
color = pink;
}
ColorAppBar(color);
}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
#Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
#Override
public Object instantiateItem(ViewGroup collection, final int position) {
LayoutInflater inflater = LayoutInflater.from(mContext);
ViewGroup layout = (ViewGroup) inflater.inflate(R.layout.child_item, collection, false);
if (campDetails.size() <= 0) {
Toast.makeText(mContext, "Error in getting camp details", Toast.LENGTH_SHORT).show();
return null;
}
if (campDetails.get(position).get("description").equals("RD") ) {
layout.setBackgroundColor(mContext.getResources().getColor(green));
} else {
layout.setBackgroundColor(mContext.getResources().getColor(pink));
}
collection.addView(layout);
this.collection = collection;
TextView eName = (TextView) layout.findViewById(R.id.en);
TextView nEName= (TextView) layout.findViewById(R.id.nen);
TextView textView6 = (TextView) layout.findViewById(R.id.textView6);
// ImageView nextImg = (ImageView) groupLayout.get(index).findViewById(R.id.nextImg);
eName.setText(campDetails.get(position).get("name"));
if (position+1 < campDetails.size()) {
nEName.setText(campDetails.get(position+1).get("name"));
textView6.setVisibility(View.VISIBLE);
} else {
nEName.setText("You are DONE!!");
textView6.setVisibility(View.INVISIBLE);
}
return layout;
}
#Override
public void destroyItem(ViewGroup collection, int position, Object view) {
collection.removeView((View) view);
}
#Override
public int getCount() {
return campDetails.size();
}
#Override
public boolean isViewFromObject(View view, Object object) {
return view == object;
}
#Override
public CharSequence getPageTitle(int position) {
return campDetails.get(position).get("name");
}
#Override
public void ColorAppBar(int color) {
colorChangeListener.ColorAppBar(color);
}
}

I finally managed to get it done.
I had to delay the function call setCurrentItem by a few milliseconds. Race condition? I don't know why this is the case but now it works perfectly.
Here is what I added in case someone else may find it useful:
pager.postDelayed(new Runnable() {
#Override
public void run() {
pager.setCurrentItem(pos);
}
}, 100);

I'm having trouble following the details well enough to pinpoint the problem, but this guy seems to have accomplished what you're trying to do: dynamically add and remove view to viewpager
hope it helps

how to fill array from JSON for image slider in android

I have image slider in android studio, but images array from inside project.
I want to use images from JSON, how to the best solution..
this is my adapter
public class adapter_image_slider extends PagerAdapter {
Context mContext;
public adapter_image_slider(Context context) {
this.mContext = context;
}
#Override
public int getCount() {
return sliderImagesId.length;
}
private int[] sliderImagesId = new int[]{
R.drawable.imghome1, R.drawable.imghome2, R.drawable.imghome3,
};
#Override
public boolean isViewFromObject(View v, Object obj) {
return v == ((ImageView) obj);
}
#Override
public Object instantiateItem(ViewGroup container, int i) {
ImageView mImageView = new ImageView(mContext);
mImageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
mImageView.setImageResource(sliderImagesId[i]);
((ViewPager) container).addView(mImageView, 0);
return mImageView;
}
#Override
public void destroyItem(ViewGroup container, int i, Object obj) {
((ViewPager) container).removeView((ImageView) obj);
}
}
and this is my main activity :
public class activity_img_slider_json extends Fragment {
private static ViewPager mPager;
private static int currentPage = 0;
private static final Integer[] XMEN= {R.drawable.imghome1,R.drawable.imghome2,R.drawable.imghome3,};
private ArrayList<Integer> XMENArray = new ArrayList<Integer>();
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.activity_img_slider_json,null);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
super.onCreate(savedInstanceState);
init();
}
private void init() {
for(int i=0;i<XMEN.length;i++)
XMENArray.add(XMEN[i]);
mPager = (ViewPager)getActivity().findViewById(R.id.pager);
mPager.setAdapter(new adapter_img_slider_json(getActivity(), XMENArray));
CircleIndicator indicator = (CircleIndicator)getActivity().findViewById(R.id.indicator);
indicator.setViewPager(mPager);
// Auto start of viewpager
final Handler handler = new Handler();
final Runnable Update = new Runnable() {
public void run() {
if (currentPage == XMEN.length) {
currentPage = 0;
}
mPager.setCurrentItem(currentPage++, true);
}
};
}
}
Thanks For Attention.