Develop Reference

Divider line in RecyclerView behaves strange when expand and collapse items

When expanding and collapsing my Recyclerview items, divider lines drawn multiple times or overdrawn with items.
Also when expanding and collapsing views, dividers thickness is getting reduced.
My problem is divider line drawn each and every time I expand and collapse item in Recyclerview.
So is it possible to prevent divider line drawing if it already drawn?
While expanding an item, divider line will move according to the view.?
Below is my RecyclerView Decoration Class used for divider line,
public class SeparatorDecoration extends RecyclerView.ItemDecoration {
private final Paint mPaint;
/**
* Create a decoration that draws a line in the given color and width between the items in the view.
* #param context a context to access the resources.
* #param color the color of the separator to draw.
* #param heightDp the height of the separator in dp.
*/
public SeparatorDecoration(#NonNull Context context, #ColorInt int color,
#FloatRange(from = 0, fromInclusive = false) float heightDp) {
mPaint = new Paint();
mPaint.setColor(color);
final float thickness = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
heightDp, context.getResources().getDisplayMetrics());
mPaint.setStrokeWidth(thickness);
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) view.getLayoutParams();
// we want to retrieve the position in the list
final int position = params.getViewAdapterPosition();
// and add a separator to any view but the last one
if (position <state.getItemCount()) {
outRect.set(40, 0, 40, (int) mPaint.getStrokeWidth()); // left, top, right, bottom
} else {
outRect.setEmpty(); // 0, 0, 0, 0
}
}
#Override
public void onDrawOver(#NonNull Canvas c, #NonNull RecyclerView parent, #NonNull RecyclerView.State state) {
final int offset = (int) (mPaint.getStrokeWidth() / 2);
// this will iterate over every visible view
for (int i = 0; i < parent.getChildCount(); i++) {
// get the view
final View view = parent.getChildAt(i);
final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) view.getLayoutParams();
// get the position
final int position = params.getViewAdapterPosition();
// and finally draw the separator
if (position < parent.getChildCount()) {
final int ty = (int)(view.getTranslationY() + 0.5f);
final int top = view.getBottom() - params.bottomMargin + ty;
final int bottom = top + (int) mPaint.getStrokeWidth();
c.drawLine(view.getLeft(), view.getBottom() + offset, view.getRight(), view.getBottom() + offset, mPaint);
}
}
}
}
below is my RecyclerView Adapter class,
public class DisplayNotificationAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
private Context context;
private List<NotificationDetails> notificationRecords;
private DeleteNotificationListener deleteNotificationListener;
private String TAG = DisplayNotificationAdapter.class.getSimpleName();
interface DeleteNotificationListener {
void updateNotificationList(List<NotificationDetails> details);
}
public DisplayNotificationAdapter(Context context, DeleteNotificationListener listener, List < NotificationDetails > notificationRecordsList) {
this.context = context;
this.deleteNotificationListener = listener;
this.notificationRecords = notificationRecordsList;
}
#NonNull
#Override
public RecyclerView.ViewHolder onCreateViewHolder (#NonNull ViewGroup parent, int viewType){
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
AndroidLogger.log(5,TAG,"oncreate");
View listItem = layoutInflater.inflate(R.layout.display_notification_recycler_view_list_item, parent, false);
return new NotificationViewHolder(listItem);
}
#RequiresApi(api = Build.VERSION_CODES.N)
#Override
public void onBindViewHolder (#NonNull RecyclerView.ViewHolder holder,int position){
NotificationDetails notification = notificationRecords.get(position);
NotificationViewHolder viewHolder = (NotificationViewHolder) holder;
String currentDateString = DateFormat.getDateInstance().format(Long.parseLong(notification.getTimeStamp()));
String filePath=generateFilePath(notification.getFileName());
Bitmap myBitmap = BitmapFactory.decodeFile(filePath);
#SuppressLint("SimpleDateFormat")
DateFormat dateFormat = new SimpleDateFormat("hh:mm aa");
String time = dateFormat.format(Long.parseLong(notification.getTimeStamp()));
if (notification.isExpanded()) {
viewHolder.expandCollapseImageView.setImageDrawable(context.getDrawable(ImageDrawable.getDrawable("Up Arrow")));
expandView(viewHolder.notificationImageview);
}
else {
viewHolder.expandCollapseImageView.setImageDrawable(context.getDrawable(ImageDrawable.getDrawable("Down Arrow")));
collapseView(viewHolder.notificationImageview);
}
viewHolder.notificationImageview.setImageBitmap(myBitmap);
viewHolder.notificationTextView.setText(notification.getMessage());
viewHolder.notificationTimeTextView.setText(time);
Calendar now = Calendar.getInstance();
Calendar date = Calendar.getInstance();
date.setTimeInMillis(Long.parseLong(notification.getTimeStamp()));
viewHolder.expandCollapseImageView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(notification.isExpanded()) {
notification.setExpanded(false);
viewHolder.expandCollapseImageView.setImageDrawable(context.getDrawable(ImageDrawable.getDrawable("Down Arrow")));
viewHolder.notificationTextView.setMaxLines(1);
notifyItemChanged(position);
}
else {
notification.setExpanded(true);
viewHolder.expandCollapseImageView.setImageDrawable(context.getDrawable(ImageDrawable.getDrawable("Up Arrow")));
viewHolder.notificationTextView.setMaxLines(Integer.MAX_VALUE);
notifyItemChanged(position);
}
}
});
if (now.get(Calendar.DATE) == date.get(Calendar.DATE))
viewHolder.notificationDateTextView.setText("Today");
else if (now.get(Calendar.DATE) - date.get(Calendar.DATE) == 1)
viewHolder.notificationDateTextView.setText("Yesterday");
else
viewHolder.notificationDateTextView.setText(currentDateString);
if(notification.getTitle()==null)
viewHolder.notificationTitleTextView.setText("title");
else
viewHolder.notificationTitleTextView.setText(notification.getTitle());
}
private String generateFilePath(String fileName) {
File imageFileDirectory = context.getDir("image", Context.MODE_PRIVATE); //Creating an internal dir;
if (!imageFileDirectory.exists()) {
imageFileDirectory.mkdirs();
}
/*
* app server provide "U" file name after we set read status they provide same file name as "R"
*/
String createFilePath = imageFileDirectory + "/" + fileName;
return createFilePath;
}
public void removeSingleNotification ( int position){
DatabaseHelper databaseHelper = new DatabaseHelper(context);
databaseHelper.deleteSingleNotificationRecord(notificationRecords.get(position).getId());
notificationRecords.remove(position);
deleteNotificationListener.updateNotificationList(notificationRecords);
notifyDataSetChanged();
}
private void removeFromList (String id) {
for (NotificationDetails detail : notificationRecords) {
if (detail.getId().equalsIgnoreCase(id))
notificationRecords.remove(detail);
}
}
#Override
public int getItemCount () {
return notificationRecords.size();
}
public void expandView(final View v) {
int matchParentMeasureSpec = View.MeasureSpec.makeMeasureSpec(((View) v.getParent()).getWidth(), View.MeasureSpec.EXACTLY);
int wrapContentMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
v.measure(matchParentMeasureSpec, wrapContentMeasureSpec);
final int targetHeight = v.getMeasuredHeight();
// Older versions of android (pre API 21) cancel animations for views with a height of 0.
v.getLayoutParams().height = 1;
v.setVisibility(View.VISIBLE);
Animation a = new Animation()
{
#Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
v.getLayoutParams().height = interpolatedTime == 1
? ViewGroup.LayoutParams.WRAP_CONTENT
: (int)(targetHeight * interpolatedTime);
v.requestLayout();
}
#Override
public boolean willChangeBounds() {
return true;
}
};
// Expansion speed of 1dp/ms
a.setDuration((int)(targetHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
}
public void collapseView(final View v) {
//collapse(pos);
final int initialHeight = v.getMeasuredHeight();
Animation a = new Animation()
{
#Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
if(interpolatedTime == 1){
v.setVisibility(View.GONE);
}else{
v.getLayoutParams().height = initialHeight - (int)(initialHeight * interpolatedTime);
v.requestLayout();
}
}
#Override
public boolean willChangeBounds() {
return true;
}
};
// Collapse speed of 1dp/ms
a.setDuration((int)(initialHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
}
public static class NotificationViewHolder extends RecyclerView.ViewHolder {
private TextView notificationTextView, notificationDateTextView, notificationTimeTextView, notificationTitleTextView;
private ImageView notificationImageview,expandCollapseImageView;
private ConstraintLayout parent;
public NotificationViewHolder(#NonNull View itemView) {
super(itemView);
notificationTextView = itemView.findViewById(R.id.notification_text_view);
notificationDateTextView = itemView.findViewById(R.id.notification_date_text_view);
notificationTimeTextView = itemView.findViewById(R.id.notification_time_text_view);
notificationTitleTextView = itemView.findViewById(R.id.notification_title_text_view);
notificationImageview = itemView.findViewById(R.id.notification_image_view);
expandCollapseImageView = itemView.findViewById(R.id.expand_collapse_arrow);
parent = itemView.findViewById(R.id.notification_parent);
}
}
}
UPDATE
I doesn't able to solve this issue. So instead of using RecyclerView.ItemDecoration I have used a View inside layout like below,
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:id="#+id/view_div"
android:background="#color/grey"
Doing like above solves the issue.
[This is my screen contains the issue][1]][1]
https://i.stack.imgur.com/CBY80.jpg

Adding Marker Pins at touched Position using subsampling scale image view

I'm using "subsampling scale image view" in my app and I would like to dynamically add marker pins to a PinView when the user does a long click on it. The marker pin should appear at the clicked position.
I achieved that a marker pin appears after a long click, but at a wrong position. Here is the onCreateView method of my Fragment:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
pinCounter=0;
View rootView = inflater.inflate(R.layout.fragment_edit_plan, container, false);
src = getArguments().getString("src");
imageView = (PinView)rootView.findViewById(R.id.imageView);
imageView.setImage(ImageSource.uri(src));
imageView.isLongClickable();
imageView.isClickable();
imageView.hasOnClickListeners();
MapPins = new ArrayList();
imageView.setPins(MapPins);
imageView.setOnLongClickListener(this);
imageView.setOnTouchListener(this);
return rootView;
}
The Listener-Methods:
#Override
public boolean onLongClick(View view) {
if (view.getId() == R.id.imageView) {
Toast.makeText(getActivity(), "Long clicked "+lastKnownX+" "+lastKnownY, Toast.LENGTH_SHORT).show();
Log.d("EditPlanFragment","Scale "+imageView.getScale());
MapPins.add(new MapPin(lastKnownX,lastKnownY,pinCounter));
imageView.setPins(MapPins);
imageView.post(new Runnable(){
public void run(){
imageView.getRootView().postInvalidate();
}
});
return true;
}
return false;
}
#Override
public boolean onTouch(View v, MotionEvent event) {
if (v.getId()== R.id.imageView && event.getAction() == MotionEvent.ACTION_DOWN){
lastKnownX= event.getX();
lastKnownY= event.getY();
}
return false;
}
My XML-File:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingTop="50dp"
>
<com.example.viktoriabock.phoenixversion1.PinView
android:id="#+id/imageView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:longClickable="true"
/>
And the PinView-Class:
public class PinView extends SubsamplingScaleImageView {
private PointF sPin;
ArrayList<MapPin> mapPins;
ArrayList<DrawPin> drawnPins;
Context context;
String tag = getClass().getSimpleName();
public PinView(Context context) {
this(context, null);
this.context = context;
}
public PinView(Context context, AttributeSet attr) {
super(context, attr);
this.context = context;
initialise();
}
public void setPins(ArrayList<MapPin> mapPins) {
this.mapPins = mapPins;
initialise();
invalidate();
}
public void setPin(PointF pin) {
this.sPin = pin;
}
public PointF getPin() {
return sPin;
}
private void initialise() {
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// Don't draw pin before image is ready so it doesn't move around during setup.
if (!isReady()) {
return;
}
drawnPins = new ArrayList<>();
Paint paint = new Paint();
paint.setAntiAlias(true);
float density = getResources().getDisplayMetrics().densityDpi;
for (int i = 0; i < mapPins.size(); i++) {
MapPin mPin = mapPins.get(i);
//Bitmap bmpPin = Utils.getBitmapFromAsset(context, mPin.getPinImgSrc());
Bitmap bmpPin = BitmapFactory.decodeResource(this.getResources(), R.drawable.pushpin_blue);
float w = (density / 420f) * bmpPin.getWidth();
float h = (density / 420f) * bmpPin.getHeight();
bmpPin = Bitmap.createScaledBitmap(bmpPin, (int) w, (int) h, true);
PointF vPin = sourceToViewCoord(mPin.getPoint());
//in my case value of point are at center point of pin image, so we need to adjust it here
float vX = vPin.x - (bmpPin.getWidth() / 2);
float vY = vPin.y - bmpPin.getHeight();
canvas.drawBitmap(bmpPin, vX, vY, paint);
//add added pin to an Array list to get touched pin
DrawPin dPin = new DrawPin();
dPin.setStartX(mPin.getX() - w / 2);
dPin.setEndX(mPin.getX() + w / 2);
dPin.setStartY(mPin.getY() - h / 2);
dPin.setEndY(mPin.getY() + h / 2);
dPin.setId(mPin.getId());
drawnPins.add(dPin);
}
}
public int getPinIdByPoint(PointF point) {
for (int i = drawnPins.size() - 1; i >= 0; i--) {
DrawPin dPin = drawnPins.get(i);
if (point.x >= dPin.getStartX() && point.x <= dPin.getEndX()) {
if (point.y >= dPin.getStartY() && point.y <= dPin.getEndY()) {
return dPin.getId();
}
}
}
return -1; //negative no means no pin selected
}
}

You're collecting the screen coordinates of the long press, then in the custom view you're converting them from source coordinates to screen coordinates. You need to convert the event coordinates into source coordinates when you get the tap event, using the view's viewToSourceCoord method.
There's an easier way to do this than using your lastKnown values - use your own GestureDetector.
For a full working example of a long press gesture detector, see the AdvancedEventHandlingActivity sample class.

Android new Inbox app style listview with swipe left and right

m trying to build android new inbox style listview with swipe left and right as shown in this image , i have tried 47deg swipelistview but its not that stable , is there any other library available?!
Tried so far with 47 deg
public class MainActivity extends Activity {
Listview pullToRefreshListView;
SwipeListView swipelistview;
ItemAdapter adapter;
List<ItemRow> itemData;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
pullToRefreshListView = (ListView) findViewById(R.id.example_swipe_lv_list);
swipelistview = pullToRefreshListView.getRefreshableView();
itemData = new ArrayList<ItemRow>();
adapter = new ItemAdapter(this, R.layout.custom_row, itemData);
swipelistview.setSwipeListViewListener(new BaseSwipeListViewListener() {
#Override
public void onOpened(int position, boolean toRight) {
if (toRight) {
adapter.remove(position);
Toast.makeText(MainActivity.this, "Open to dismiss",
Toast.LENGTH_SHORT).show();
} // swipelistview.dismiss(position);
else {
Toast.makeText(MainActivity.this, "Open to edit",
Toast.LENGTH_SHORT).show();
}
}
#Override
public void onClosed(int position, boolean fromRight) {
}
#Override
public void onListChanged() {
}
#Override
public void onMove(int position, float x) {
}
#Override
public void onStartOpen(int position, int action, boolean right) {
if (right) {
// adapter.onRight();
swipelistview.getChildAt(position).findViewById(R.id.back)
.setBackgroundColor(Color.GREEN);
swipelistview.getChildAt(position)
.findViewById(R.id.imageViewLeft)
.setVisibility(View.VISIBLE);
swipelistview.getChildAt(position)
.findViewById(R.id.imageViewRight)
.setVisibility(View.GONE);
} else {
// adapter.onLeft();
swipelistview.getChildAt(position).findViewById(R.id.back)
.setBackgroundColor(Color.RED);
swipelistview.getChildAt(position)
.findViewById(R.id.imageViewLeft)
.setVisibility(View.GONE);
swipelistview.getChildAt(position)
.findViewById(R.id.imageViewRight)
.setVisibility(View.VISIBLE);
}
}
#Override
public void onStartClose(int position, boolean right) {
Log.d("swipe", String.format("onStartClose %d", position));
}
#Override
public void onClickFrontView(int position) {
Log.d("swipe", String.format("onClickFrontView %d", position));
// swipelistview.openAnimate(position); //when you touch front
// view it will open
}
#Override
public void onClickBackView(int position) {
Log.d("swipe", String.format("onClickBackView %d", position));
// swipelistview.closeAnimate(position);//when you touch back
// view it will close
}
#Override
public void onDismiss(int[] reverseSortedPositions) {
}
});
// These are the swipe listview settings. you can change these
// setting as your requirement
swipelistview.setSwipeMode(SwipeListView.SWIPE_MODE_BOTH); // there are
// five
// swiping
// modes
swipelistview.setSwipeActionRight(SwipeListView.SWIPE_ACTION_REVEAL); // there
// are
// four
// swipe
// actions
swipelistview.setSwipeActionLeft(SwipeListView.SWIPE_ACTION_REVEAL);
swipelistview.setOffsetRight(convertDpToPixel(0f)); // left side
// offset
swipelistview.setOffsetLeft(convertDpToPixel(0f)); // right side
// offset
swipelistview.setAnimationTime(60); // Animation time
swipelistview.setSwipeOpenOnLongPress(false); // enable or disable
// SwipeOpenOnLongPress
swipelistview.setSwipeCloseAllItemsWhenMoveList(true);
swipelistview.setAdapter(adapter);
for (int i = 0; i < 10; i++) {
itemData.add(new ItemRow("Swipe Item" + i, getResources()
.getDrawable(R.drawable.ic_launcher)));
}
adapter.notifyDataSetChanged();
}
public int convertDpToPixel(float dp) {
DisplayMetrics metrics = getResources().getDisplayMetrics();
float px = dp * (metrics.densityDpi / 160f);
return (int) px;
}
}
Adapter class
public class ItemAdapter extends ArrayAdapter<ItemRow> {
List<ItemRow> data;
Context context;
int layoutResID;
public ItemAdapter(Context context, int layoutResourceId, List<ItemRow> data) {
super(context, layoutResourceId, data);
this.data = data;
this.context = context;
this.layoutResID = layoutResourceId;
// TODO Auto-generated constructor stub
}
NewsHolder holder = null;
View row = null;
#Override
public View getView(int position, View convertView, ViewGroup parent) {
row = convertView;
holder = null;
if (row == null) {
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
row = inflater.inflate(layoutResID, parent, false);
holder = new NewsHolder();
holder.itemName = (TextView) row
.findViewById(R.id.example_itemname);
holder.icon = (ImageView) row.findViewById(R.id.example_image);
holder.imageViewRight = (ImageView) row
.findViewById(R.id.imageViewRight);
holder.imageViewLeft = (ImageView) row
.findViewById(R.id.imageViewLeft);
row.setTag(holder);
} else {
holder = (NewsHolder) row.getTag();
}
ItemRow itemdata = data.get(position);
holder.itemName.setText(itemdata.getItemName());
holder.icon.setImageDrawable(itemdata.getIcon());
return row;
}
public void remove(int pos){
data.remove(pos);
}
public void onLeft() {
holder.imageViewLeft.setVisibility(View.VISIBLE);
holder.imageViewRight.setVisibility(View.GONE);
}
public void onRight() {
holder.imageViewRight.setVisibility(View.VISIBLE);
holder.imageViewLeft.setVisibility(View.GONE);
}
static class NewsHolder {
TextView itemName;
ImageView icon;
ImageView imageViewLeft, imageViewRight;
RelativeLayout mRelativeLayout;
}

Instead of using a custom ListView you can simply support "swipe" gesture on list items onTouch, like the following:
private static final int DEFAULT_THRESHOLD = 128;
row.setOnTouchListener(new View.OnTouchListener() {
int initialX = 0;
final float slop = ViewConfiguration.get(context).getScaledTouchSlop();
public boolean onTouch(final View view, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
initialX = (int) event.getX();
view.setPadding(0, 0, 0, 0);
} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
int currentX = (int) event.getX();
int offset = currentX - initialX;
if (Math.abs(offset) > slop) {
view.setPadding(offset, 0, 0, 0);
if (offset > DEFAULT_THRESHOLD) {
// TODO :: Do Right to Left action! And do nothing on action_up.
} else if (offset < -DEFAULT_THRESHOLD) {
// TODO :: Do Left to Right action! And do nothing on action_up.
}
}
} else if (event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL) {
// Animate back if no action was performed.
ValueAnimator animator = ValueAnimator.ofInt(view.getPaddingLeft(), 0);
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator valueAnimator) {
view.setPadding((Integer) valueAnimator.getAnimatedValue(), 0, 0, 0);
}
});
animator.setDuration(150);
animator.start();
}
};
I also use reverse animation if no action was performed.
This solution is lightweight so you should not experience any lags.

Check out: SwipeActionAdapter
It's a great library that does exactly what you're asking for. It allows Swipe in both directions with an underlying Layout or Color. It's easy to implement and looks nice!

Updated Answer
As I mentioned previously, I took the same approach and it seems to work as expected. I have added 3 layers to a RelativeLayout. Top layer is what you want to show. Second layer is a plain background with delete icon at the left. Third layer is another plain background with share icon at the right. I implemented a swipe detector class which extends View.OnTouchListener.
public class SwipeDetector implements View.OnTouchListener {
private static final int MIN_DISTANCE = 300;
private static final int MIN_LOCK_DISTANCE = 30; // disallow motion intercept
private boolean motionInterceptDisallowed = false;
private float downX, upX;
private ObjectHolder holder;
private int position;
public SwipeDetector(ObjectHolder h, int pos) {
holder = h;
position = pos;
}
#Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN: {
downX = event.getX();
return true; // allow other events like Click to be processed
}
case MotionEvent.ACTION_MOVE: {
upX = event.getX();
float deltaX = downX - upX;
if (Math.abs(deltaX) > MIN_LOCK_DISTANCE && listView != null && !motionInterceptDisallowed) {
listView.requestDisallowInterceptTouchEvent(true);
motionInterceptDisallowed = true;
}
if (deltaX > 0) {
holder.deleteView.setVisibility(View.GONE);
} else {
// if first swiped left and then swiped right
holder.deleteView.setVisibility(View.VISIBLE);
}
swipe(-(int) deltaX);
return true;
}
case MotionEvent.ACTION_UP:
upX = event.getX();
float deltaX = upX - downX;
if (Math.abs(deltaX) > MIN_DISTANCE) {
// left or right
swipeRemove();
} else {
swipe(0);
}
if (listView != null) {
listView.requestDisallowInterceptTouchEvent(false);
motionInterceptDisallowed = false;
}
holder.deleteView.setVisibility(View.VISIBLE);
return true;
case MotionEvent.ACTION_CANCEL:
holder.deleteView.setVisibility(View.VISIBLE);
return false;
}
return true;
}
private void swipe(int distance) {
View animationView = holder.mainView;
RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) animationView.getLayoutParams();
params.rightMargin = -distance;
params.leftMargin = distance;
animationView.setLayoutParams(params);
}
private void swipeRemove() {
remove(getItem(position));
notifyDataSetChanged();
}
}
public static class ObjectHolder {
public LinearLayout mainView;
public RelativeLayout deleteView;
public RelativeLayout shareView;
/* other views here */
}
I have also added requestDisallowInterceptTouchEvent so that ListView (which is parent) doesn't intercept the touch event when there's some amount of vertical scrolling involved.
I have written a blogpost about it which you can find it here. I have also added a Youtube video for demo.
Old Answer
I implemented one of these myself, but it's a bit different. I use just touch instead of swiping. Touch to open, touch to close. Here's youtube demo.
I created custom ArrayAdapter. To set the layout, I created a custom layout like this.
<RelativeLayout>
<RelativeLayout>
<Stuff that you want at the back of your list/>
</RelativeLayout>
<RelativeLayout>
<Stuff that you want at the front of your list/>
</RelativeLayout>
</RelativeLayout>
Using RelativeLayout, I am putting the top view over the bottom view. Both have same sizes. You can use different layouts for inner layouts.
In Custom ArrayAdapter,
#Override
public view getView(int position, View convertView, ViewGroup parent) {
// get holder and entry
// set each element based on entry preferences
holder.topView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (entry.isSwiped()) {
swipeWithAnimationValue(holder.topView, 1);
entry.setSwiped(false);
} else {
closeOtherSwipes(entry); // if you want to keep only one entry open at a time
swipeWithAnimationValue(holder.topView, 0);
entry.setSwiped(true);
}
}
});
}
Normal Animation would not work as it just shifts the view, but it's still there so if you try to click, the click still occurs on the top view. Hence I have used valueAnimator and actually shifted those lists.
public void swipeWithAnimationValue(final View view, final int direction) {
final int width = view.getWidth();
Log.i(TAG, "view width = " + String.valueOf(width));
ValueAnimator animationSwipe;
int duration = 300;
if (direction == 0) {
animationSwipe = ValueAnimator.ofInt(0, view.getWidth() - 200);
} else {
animationSwipe = ValueAnimator.ofInt(view.getWidth() - 200, 0);
}
animationSwipe.setDuration(duration);
AnimatorUpdateListener maringUpdater = new AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator animation) {
RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) view.getLayoutParams();
params.rightMargin = -(Integer)animation.getAnimatedValue();
params.leftMargin = (Integer)animation.getAnimatedValue();
view.setLayoutParams(params);
}
};
animationSwipe.addUpdateListener(maringUpdater);
animationSwipe.setRepeatCount(0);
animationSwipe.start();
}

Drag and Drop for listview of views

Hi i am having Listview where each item is having different layout.and i want to perform drag and drop on this listview.i have searched many examples and tried but all works for listview of strings or something like that,none is working on listview of views.finally i decided to go with
DevBytes: ListView Cell Dragging and Rearranging this one.i implemented dynaliclistview but it is crashing as this also using strings in listview.Following is my listview adapter
public class ListViewPagerAdapter extends BaseAdapter {
ViewPagerAdapter mViewPagerAdapter;
private Context context;
private int selectedIndex;
FragmentManager mFragmentManager;
static ViewPager vp;
LayoutInflater inflater;
private ArrayList<Integer> mContent;
public ListViewPagerAdapter(Context context,FragmentManager fg)
{
super();
this.context = context;
mFragmentManager = fg;
}
#Override
public int getCount() {
return 4;
}
public void setSelectedIndex(int position) {
selectedIndex = position;
notifyDataSetChanged();
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
if (convertView == null) {
inflater = (LayoutInflater) context
.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
if(position==0)
{
convertView = inflater.inflate(R.layout.titlebar, null);
}
}
if(position==0)
{
convertView = inflater.inflate(R.layout.titlebar, null);
}
if(position==1)
{LayoutInflater inflater1 = (LayoutInflater) context
.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
convertView = inflater1.inflate(R.layout.calendarwidget_layout, null);
}
if(position==2)
{
LayoutInflater inflater2 = (LayoutInflater) context
.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
convertView = inflater2.inflate(R.layout.view_pager_list_view, null);
vp = (ViewPager) convertView.findViewById(R.id.list_pager);
mViewPagerAdapter = new ViewPagerAdapter(mFragmentManager);
vp.setAdapter(mViewPagerAdapter);
}
if(position==3)
{
LayoutInflater inflater2 = (LayoutInflater) context
.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
convertView = inflater2.inflate(R.layout.view_pager_list_view, null);
vp = (ViewPager) convertView.findViewById(R.id.list_pager);
mViewPagerAdapter = new ViewPagerAdapter(mFragmentManager);
vp.setAdapter(mViewPagerAdapter);
mViewPagerAdapter.notifyDataSetChanged();
}
return convertView;
}
#Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}
}
and following is code for dynamiclisview (same as from mentioned example)
public class DynamicListView extends ListView {
private final int SMOOTH_SCROLL_AMOUNT_AT_EDGE = 15;
private final int MOVE_DURATION = 150;
private final int LINE_THICKNESS = 15;
public ArrayList<String> mCheeseList;
private int mLastEventY = -1;
private int mDownY = -1;
private int mDownX = -1;
private int mTotalOffset = 0;
private boolean mCellIsMobile = false;
private boolean mIsMobileScrolling = false;
private int mSmoothScrollAmountAtEdge = 0;
private final int INVALID_ID = -1;
private long mAboveItemId = INVALID_ID;
private long mMobileItemId = INVALID_ID;
private long mBelowItemId = INVALID_ID;
private BitmapDrawable mHoverCell;
private Rect mHoverCellCurrentBounds;
private Rect mHoverCellOriginalBounds;
private final int INVALID_POINTER_ID = -1;
private int mActivePointerId = INVALID_POINTER_ID;
private boolean mIsWaitingForScrollFinish = false;
private int mScrollState = OnScrollListener.SCROLL_STATE_IDLE;
public DynamicListView(Context context) {
super(context);
init(context);
}
public DynamicListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
public DynamicListView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public void init(Context context) {
setOnItemLongClickListener(mOnItemLongClickListener);
setOnScrollListener(mScrollListener);
DisplayMetrics metrics = context.getResources().getDisplayMetrics();
mSmoothScrollAmountAtEdge = (int)(SMOOTH_SCROLL_AMOUNT_AT_EDGE / metrics.density);
}
/**
* Listens for long clicks on any items in the listview. When a cell has
* been selected, the hover cell is created and set up.
*/
private AdapterView.OnItemLongClickListener mOnItemLongClickListener =
new AdapterView.OnItemLongClickListener() {
public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int pos, long id) {
mTotalOffset = 0;
int position = pointToPosition(mDownX, mDownY);
int itemNum = position - getFirstVisiblePosition();
View selectedView = getChildAt(itemNum);
mMobileItemId = getAdapter().getItemId(position);
mHoverCell = getAndAddHoverView(selectedView);
selectedView.setVisibility(INVISIBLE);
mCellIsMobile = true;
updateNeighborViewsForID(mMobileItemId);
return true;
}
};
/**
* Creates the hover cell with the appropriate bitmap and of appropriate
* size. The hover cell's BitmapDrawable is drawn on top of the bitmap every
* single time an invalidate call is made.
*/
private BitmapDrawable getAndAddHoverView(View v) {
int w = v.getWidth();
int h = v.getHeight();
int top = v.getTop();
int left = v.getLeft();
Bitmap b = getBitmapWithBorder(v);
BitmapDrawable drawable = new BitmapDrawable(getResources(), b);
mHoverCellOriginalBounds = new Rect(left, top, left + w, top + h);
mHoverCellCurrentBounds = new Rect(mHoverCellOriginalBounds);
drawable.setBounds(mHoverCellCurrentBounds);
return drawable;
}
/** Draws a black border over the screenshot of the view passed in. */
private Bitmap getBitmapWithBorder(View v) {
Bitmap bitmap = getBitmapFromView(v);
Canvas can = new Canvas(bitmap);
Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
Paint paint = new Paint();
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(LINE_THICKNESS);
paint.setColor(Color.BLACK);
can.drawBitmap(bitmap, 0, 0, null);
can.drawRect(rect, paint);
return bitmap;
}
/** Returns a bitmap showing a screenshot of the view passed in. */
private Bitmap getBitmapFromView(View v) {
Bitmap bitmap = Bitmap.createBitmap(v.getWidth(), v.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas (bitmap);
v.draw(canvas);
return bitmap;
}
/**
* Stores a reference to the views above and below the item currently
* corresponding to the hover cell. It is important to note that if this
* item is either at the top or bottom of the list, mAboveItemId or mBelowItemId
* may be invalid.
*/
private void updateNeighborViewsForID(long itemID) {
int position = getPositionForID(itemID);
ListViewPagerAdapter adapter = ((ListViewPagerAdapter)getAdapter());
mAboveItemId = adapter.getItemId(position - 1);
mBelowItemId = adapter.getItemId(position + 1);
}
/** Retrieves the view in the list corresponding to itemID */
public View getViewForID (long itemID) {
int firstVisiblePosition = getFirstVisiblePosition();
ListViewPagerAdapter adapter = ((ListViewPagerAdapter)getAdapter());
for(int i = 0; i < getChildCount(); i++) {
View v = getChildAt(i);
int position = firstVisiblePosition + i;
long id = adapter.getItemId(position);
if (id == itemID) {
return v;
}
}
return null;
}
/** Retrieves the position in the list corresponding to itemID */
public int getPositionForID (long itemID) {
View v = getViewForID(itemID);
if (v == null) {
return -1;
} else {
return getPositionForView(v);
}
}
/**
* dispatchDraw gets invoked when all the child views are about to be drawn.
* By overriding this method, the hover cell (BitmapDrawable) can be drawn
* over the listview's items whenever the listview is redrawn.
*/
#Override
protected void dispatchDraw(Canvas canvas) {
super.dispatchDraw(canvas);
if (mHoverCell != null) {
mHoverCell.draw(canvas);
}
}
#Override
public boolean onTouchEvent (MotionEvent event) {
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
mDownX = (int)event.getX();
mDownY = (int)event.getY();
mActivePointerId = event.getPointerId(0);
break;
case MotionEvent.ACTION_MOVE:
if (mActivePointerId == INVALID_POINTER_ID) {
break;
}
int pointerIndex = event.findPointerIndex(mActivePointerId);
mLastEventY = (int) event.getY(pointerIndex);
int deltaY = mLastEventY - mDownY;
if (mCellIsMobile) {
mHoverCellCurrentBounds.offsetTo(mHoverCellOriginalBounds.left,
mHoverCellOriginalBounds.top + deltaY + mTotalOffset);
mHoverCell.setBounds(mHoverCellCurrentBounds);
invalidate();
handleCellSwitch();
mIsMobileScrolling = false;
handleMobileCellScroll();
return false;
}
break;
case MotionEvent.ACTION_UP:
touchEventsEnded();
break;
case MotionEvent.ACTION_CANCEL:
touchEventsCancelled();
break;
case MotionEvent.ACTION_POINTER_UP:
/* If a multitouch event took place and the original touch dictating
* the movement of the hover cell has ended, then the dragging event
* ends and the hover cell is animated to its corresponding position
* in the listview. */
pointerIndex = (event.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >>
MotionEvent.ACTION_POINTER_INDEX_SHIFT;
final int pointerId = event.getPointerId(pointerIndex);
if (pointerId == mActivePointerId) {
touchEventsEnded();
}
break;
default:
break;
}
return super.onTouchEvent(event);
}
/**
* This method determines whether the hover cell has been shifted far enough
* to invoke a cell swap. If so, then the respective cell swap candidate is
* determined and the data set is changed. Upon posting a notification of the
* data set change, a layout is invoked to place the cells in the right place.
* Using a ViewTreeObserver and a corresponding OnPreDrawListener, we can
* offset the cell being swapped to where it previously was and then animate it to
* its new position.
*/
private void handleCellSwitch() {
final int deltaY = mLastEventY - mDownY;
int deltaYTotal = mHoverCellOriginalBounds.top + mTotalOffset + deltaY;
View belowView = getViewForID(mBelowItemId);
View mobileView = getViewForID(mMobileItemId);
View aboveView = getViewForID(mAboveItemId);
boolean isBelow = (belowView != null) && (deltaYTotal > belowView.getTop());
boolean isAbove = (aboveView != null) && (deltaYTotal < aboveView.getTop());
if (isBelow || isAbove) {
final long switchItemID = isBelow ? mBelowItemId : mAboveItemId;
View switchView = isBelow ? belowView : aboveView;
final int originalItem = getPositionForView(mobileView);
if (switchView == null) {
updateNeighborViewsForID(mMobileItemId);
return;
}
swapElements(mCheeseList, originalItem, getPositionForView(switchView));
((BaseAdapter) getAdapter()).notifyDataSetChanged();
mDownY = mLastEventY;
final int switchViewStartTop = switchView.getTop();
mobileView.setVisibility(View.VISIBLE);
switchView.setVisibility(View.INVISIBLE);
updateNeighborViewsForID(mMobileItemId);
final ViewTreeObserver observer = getViewTreeObserver();
observer.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
#SuppressLint("NewApi")
public boolean onPreDraw() {
observer.removeOnPreDrawListener(this);
View switchView = getViewForID(switchItemID);
mTotalOffset += deltaY;
int switchViewNewTop = switchView.getTop();
int delta = switchViewStartTop - switchViewNewTop;
switchView.setTranslationY(delta);
ObjectAnimator animator = ObjectAnimator.ofFloat(switchView,
View.TRANSLATION_Y, 0);
animator.setDuration(MOVE_DURATION);
animator.start();
return true;
}
});
}
}
private void swapElements(ArrayList arrayList, int indexOne, int indexTwo) {
Object temp = arrayList.get(indexOne);
arrayList.set(indexOne, arrayList.get(indexTwo));
arrayList.set(indexTwo, temp);
}
/**
* Resets all the appropriate fields to a default state while also animating
* the hover cell back to its correct location.
*/
private void touchEventsEnded () {
final View mobileView = getViewForID(mMobileItemId);
if (mCellIsMobile|| mIsWaitingForScrollFinish) {
mCellIsMobile = false;
mIsWaitingForScrollFinish = false;
mIsMobileScrolling = false;
mActivePointerId = INVALID_POINTER_ID;
// If the autoscroller has not completed scrolling, we need to wait for it to
// finish in order to determine the final location of where the hover cell
// should be animated to.
if (mScrollState != OnScrollListener.SCROLL_STATE_IDLE) {
mIsWaitingForScrollFinish = true;
return;
}
mHoverCellCurrentBounds.offsetTo(mHoverCellOriginalBounds.left, mobileView.getTop());
ObjectAnimator hoverViewAnimator = ObjectAnimator.ofObject(mHoverCell, "bounds",
sBoundEvaluator, mHoverCellCurrentBounds);
hoverViewAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
#Override
public void onAnimationUpdate(ValueAnimator valueAnimator) {
invalidate();
}
});
hoverViewAnimator.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationStart(Animator animation) {
setEnabled(false);
}
#Override
public void onAnimationEnd(Animator animation) {
mAboveItemId = INVALID_ID;
mMobileItemId = INVALID_ID;
mBelowItemId = INVALID_ID;
mobileView.setVisibility(VISIBLE);
mHoverCell = null;
setEnabled(true);
invalidate();
}
});
hoverViewAnimator.start();
} else {
touchEventsCancelled();
}
}
/**
* Resets all the appropriate fields to a default state.
*/
private void touchEventsCancelled () {
View mobileView = getViewForID(mMobileItemId);
if (mCellIsMobile) {
mAboveItemId = INVALID_ID;
mMobileItemId = INVALID_ID;
mBelowItemId = INVALID_ID;
mobileView.setVisibility(VISIBLE);
mHoverCell = null;
invalidate();
}
mCellIsMobile = false;
mIsMobileScrolling = false;
mActivePointerId = INVALID_POINTER_ID;
}
/**
* This TypeEvaluator is used to animate the BitmapDrawable back to its
* final location when the user lifts his finger by modifying the
* BitmapDrawable's bounds.
*/
private final static TypeEvaluator<Rect> sBoundEvaluator = new TypeEvaluator<Rect>() {
public Rect evaluate(float fraction, Rect startValue, Rect endValue) {
return new Rect(interpolate(startValue.left, endValue.left, fraction),
interpolate(startValue.top, endValue.top, fraction),
interpolate(startValue.right, endValue.right, fraction),
interpolate(startValue.bottom, endValue.bottom, fraction));
}
public int interpolate(int start, int end, float fraction) {
return (int)(start + fraction * (end - start));
}
};
/**
* Determines whether this listview is in a scrolling state invoked
* by the fact that the hover cell is out of the bounds of the listview;
*/
private void handleMobileCellScroll() {
mIsMobileScrolling = handleMobileCellScroll(mHoverCellCurrentBounds);
}
/**
* This method is in charge of determining if the hover cell is above
* or below the bounds of the listview. If so, the listview does an appropriate
* upward or downward smooth scroll so as to reveal new items.
*/
public boolean handleMobileCellScroll(Rect r) {
int offset = computeVerticalScrollOffset();
int height = getHeight();
int extent = computeVerticalScrollExtent();
int range = computeVerticalScrollRange();
int hoverViewTop = r.top;
int hoverHeight = r.height();
if (hoverViewTop <= 0 && offset > 0) {
smoothScrollBy(-mSmoothScrollAmountAtEdge, 0);
return true;
}
if (hoverViewTop + hoverHeight >= height && (offset + extent) < range) {
smoothScrollBy(mSmoothScrollAmountAtEdge, 0);
return true;
}
return false;
}
public void setCheeseList(ArrayList<String> cheeseList) {
mCheeseList = cheeseList;
}
/**
* This scroll listener is added to the listview in order to handle cell swapping
* when the cell is either at the top or bottom edge of the listview. If the hover
* cell is at either edge of the listview, the listview will begin scrolling. As
* scrolling takes place, the listview continuously checks if new cells became visible
* and determines whether they are potential candidates for a cell swap.
*/
private AbsListView.OnScrollListener mScrollListener = new AbsListView.OnScrollListener () {
private int mPreviousFirstVisibleItem = -1;
private int mPreviousVisibleItemCount = -1;
private int mCurrentFirstVisibleItem;
private int mCurrentVisibleItemCount;
private int mCurrentScrollState;
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
int totalItemCount) {
mCurrentFirstVisibleItem = firstVisibleItem;
mCurrentVisibleItemCount = visibleItemCount;
mPreviousFirstVisibleItem = (mPreviousFirstVisibleItem == -1) ? mCurrentFirstVisibleItem
: mPreviousFirstVisibleItem;
mPreviousVisibleItemCount = (mPreviousVisibleItemCount == -1) ? mCurrentVisibleItemCount
: mPreviousVisibleItemCount;
checkAndHandleFirstVisibleCellChange();
checkAndHandleLastVisibleCellChange();
mPreviousFirstVisibleItem = mCurrentFirstVisibleItem;
mPreviousVisibleItemCount = mCurrentVisibleItemCount;
}
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
mCurrentScrollState = scrollState;
mScrollState = scrollState;
isScrollCompleted();
}
/**
* This method is in charge of invoking 1 of 2 actions. Firstly, if the listview
* is in a state of scrolling invoked by the hover cell being outside the bounds
* of the listview, then this scrolling event is continued. Secondly, if the hover
* cell has already been released, this invokes the animation for the hover cell
* to return to its correct position after the listview has entered an idle scroll
* state.
*/
private void isScrollCompleted() {
if (mCurrentVisibleItemCount > 0 && mCurrentScrollState == SCROLL_STATE_IDLE) {
if (mCellIsMobile && mIsMobileScrolling) {
handleMobileCellScroll();
} else if (mIsWaitingForScrollFinish) {
touchEventsEnded();
}
}
}
/**
* Determines if the listview scrolled up enough to reveal a new cell at the
* top of the list. If so, then the appropriate parameters are updated.
*/
public void checkAndHandleFirstVisibleCellChange() {
if (mCurrentFirstVisibleItem != mPreviousFirstVisibleItem) {
if (mCellIsMobile && mMobileItemId != INVALID_ID) {
updateNeighborViewsForID(mMobileItemId);
handleCellSwitch();
}
}
}
/**
* Determines if the listview scrolled down enough to reveal a new cell at the
* bottom of the list. If so, then the appropriate parameters are updated.
*/
public void checkAndHandleLastVisibleCellChange() {
int currentLastVisibleItem = mCurrentFirstVisibleItem + mCurrentVisibleItemCount;
int previousLastVisibleItem = mPreviousFirstVisibleItem + mPreviousVisibleItemCount;
if (currentLastVisibleItem != previousLastVisibleItem) {
if (mCellIsMobile && mMobileItemId != INVALID_ID) {
updateNeighborViewsForID(mMobileItemId);
handleCellSwitch();
}
}
}
};
}
And following is list.xml
<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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<com.bin.widget.DynamicListView
android:id="#+id/campaignListView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#0000"
>
</com.bin.widget.DynamicListView>
</RelativeLayout>
please help me out...thanks in advance

HI I finally solved this problem myself,above code works by making few changes in adapter class of listview.In adapter's public long getItemId(int position) make necessary changes so that it will give you id of passed positions view.Dont just return position. Also,in dynamicListview class after swapping position refresh of listview is being done so in listadapter's getview() method,we need to make changes accordingly.
That's it,then it works like charm.Hope this helps somebody else too.

Android Gallery zoom in/out

Hi I am using the Gallery widget to show images downloaded from the internet.
to show several images and I would like to have a gradual zoom while people slide up and down on the screen. I know how to implement the touch event the only thing I don't know how to make the whole gallery view grow gradually. I don't want to zoom in on one image I want the whole gallery to zoom in/out gradually.
EDIT3: I manage to zoom the visible part of the gallery but the problem is I need to find a way for the gallery to find out about it and update it's other children too.
What happens is if 3 images are visible then you start zooming and the gallery does get smaller, so do the images but what I would like in this case is more images to be visible but I don't know how to reach this desired effect. Here's the entire code:
public class Gallery1 extends Activity implements OnTouchListener {
private static final String TAG = "GalleryTest";
private float zoom=0.0f;
// Remember some things for zooming
PointF start = new PointF();
PointF mid = new PointF();
Gallery g;
LinearLayout layout2;
private ImageAdapter ad;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gallery_1);
layout2=(LinearLayout) findViewById(R.id.layout2);
// Reference the Gallery view
g = (Gallery) findViewById(R.id.gallery);
// Set the adapter to our custom adapter (below)
ad=new ImageAdapter(this);
g.setAdapter(ad);
layout2.setOnTouchListener(this);
}
public void zoomList(boolean increase) {
Log.i(TAG, "startig animation");
AnimatorSet set = new AnimatorSet();
set.playTogether(
ObjectAnimator.ofFloat(g, "scaleX", zoom),
ObjectAnimator.ofFloat(g, "scaleY", zoom)
);
set.addListener(new AnimatorListener() {
#Override
public void onAnimationStart(Animator animation) {
}
#Override
public void onAnimationRepeat(Animator animation) {
// TODO Auto-generated method stub
}
#Override
public void onAnimationEnd(Animator animation) {
}
#Override
public void onAnimationCancel(Animator animation) {
// TODO Auto-generated method stub
}
});
set.setDuration(100).start();
}
public class ImageAdapter extends BaseAdapter {
private static final int ITEM_WIDTH = 136;
private static final int ITEM_HEIGHT = 88;
private final int mGalleryItemBackground;
private final Context mContext;
private final Integer[] mImageIds = {
R.drawable.gallery_photo_1,
R.drawable.gallery_photo_2,
R.drawable.gallery_photo_3,
R.drawable.gallery_photo_4,
R.drawable.gallery_photo_5,
R.drawable.gallery_photo_6,
R.drawable.gallery_photo_7,
R.drawable.gallery_photo_8
};
private final float mDensity;
public ImageAdapter(Context c) {
mContext = c;
// See res/values/attrs.xml for the <declare-styleable> that defines
// Gallery1.
TypedArray a = obtainStyledAttributes(R.styleable.Gallery1);
mGalleryItemBackground = a.getResourceId(
R.styleable.Gallery1_android_galleryItemBackground, 1);
a.recycle();
mDensity = c.getResources().getDisplayMetrics().density;
}
public int getCount() {
return mImageIds.length;
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
convertView = new ImageView(mContext);
imageView = (ImageView) convertView;
imageView.setScaleType(ImageView.ScaleType.FIT_XY);
imageView.setLayoutParams(new Gallery.LayoutParams(
(int) (ITEM_WIDTH * mDensity + 0.5f),
(int) (ITEM_HEIGHT * mDensity + 0.5f)));
} else {
imageView = (ImageView) convertView;
}
imageView.setImageResource(mImageIds[position]);
return imageView;
}
}
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_MOVE
&& event.getPointerCount() > 1) {
midPoint(mid, event);
if(mid.y > start.y){
Log.i(TAG, "Going down (Math.abs(mid.y - start.y)= "+(Math.abs(mid.y - start.y))+" and zoom="+zoom); // going down so increase
if ((Math.abs(mid.y - start.y) > 10) && (zoom<2.5f)){
zoom=zoom+0.1f;
midPoint(start, event);
zoomList(true);
}
return true;
}else if(mid.y < start.y){
Log.i(TAG, "Going up (Math.abs(mid.y - start.y)= "+(Math.abs(mid.y - start.y))+" and zoom="+zoom); //smaller
if ((Math.abs(mid.y - start.y) > 10) &&(zoom>0.1)){
midPoint(start, event);
zoom=zoom-0.1f;
zoomList(false);
}
return true;
}
}
else if (event.getAction() == MotionEvent.ACTION_POINTER_DOWN) {
Log.e(TAG, "Pointer went down: " + event.getPointerCount());
return true;
}
else if (event.getAction() == MotionEvent.ACTION_UP) {
Log.i(TAG, "Pointer going up");
return true;
}
else if (event.getAction() == MotionEvent.ACTION_DOWN) {
Log.i(TAG, "Pointer going down");
start.set(event.getX(), event.getY());
return true;
}
return false;
// indicate event was handled or not
}
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
I realise I will probably have to extend the Gallery or even another View group or create my own class but I don't know where to start: which method use the one responsible for scaling...
EDIT4: I don't know if he question is clear enough. Here is an example of states:
State one: initial state, we have 3 images in view
State 2: we detect vertical touches going up with 2 fingers = we have to zoom out
state 3: we start zooming = animation on the gallery or on the children???
state 4: gallery detects that it's 3 children are smaller
state 5: gallery adds 1 /more children according to the new available space
LAST UPDATE:
Thanks to all that have posted but I have finally reached a conclusion and that is to not use Gallery at all:
1. It's deprecated
2. It's not customizable enough for my case
If you want to animate several images at once you may want to consider using OpenGl, I am using libgdx library:
https://github.com/libgdx/libgdx

The following ScalingGallery implementation might be of help.
This gallery subclass overrides the getChildStaticTransformation(View child, Transformation t) method in which the scaling is performed. You can further customize the scaling parameters to fit your own needs.
Please note the ScalingGalleryItemLayout.java class. This is necessary because after you have performed the scaling operationg on the child views, their hit boxes are no longer valid so they must be updated from with the getChildStaticTransformation(View child, Transformation t) method.
This is done by wrapping each gallery item in a ScalingGalleryItemLayout which extends a LinearLayout. Again, you can customize this to fit your own needs if a LinearLayout does not meet your needs for layout out your gallery items.
File : /src/com/example/ScalingGallery.java
/**
* A Customized Gallery component which alters the size and position of its items based on their position in the Gallery.
*/
public class ScalingGallery extends Gallery {
public static final int ITEM_SPACING = -20;
private static final float SIZE_SCALE_MULTIPLIER = 0.25f;
private static final float ALPHA_SCALE_MULTIPLIER = 0.5f;
private static final float X_OFFSET = 20.0f;
/**
* Implemented by child view to adjust the boundaries after it has been matrix transformed.
*/
public interface SetHitRectInterface {
public void setHitRect(RectF newRect);
}
/**
* #param context
* Context that this Gallery will be used in.
* #param attrs
* Attributes for this Gallery (via either xml or in-code)
*/
public ScalingGallery(Context context, AttributeSet attrs) {
super(context, attrs);
setStaticTransformationsEnabled(true);
setChildrenDrawingOrderEnabled(true);
}
/**
* {#inheritDoc}
*
* #see #setStaticTransformationsEnabled(boolean)
*
* This is where the scaling happens.
*/
protected boolean getChildStaticTransformation(View child, Transformation t) {
child.invalidate();
t.clear();
t.setTransformationType(Transformation.TYPE_BOTH);
// Position of the child in the Gallery (... +2 +1 0 -1 -2 ... 0 being the middle)
final int childPosition = getSelectedItemPosition() - getPositionForView(child);
final int childPositionAbs = (int) Math.abs(childPosition);
final float left = child.getLeft();
final float top = child.getTop();
final float right = child.getRight();
final float bottom = child.getBottom();
Matrix matrix = t.getMatrix();
RectF modifiedHitBox = new RectF();
// Change alpha, scale and translate non-middle child views.
if (childPosition != 0) {
final int height = child.getMeasuredHeight();
final int width = child.getMeasuredWidth();
// Scale the size.
float scaledSize = 1.0f - (childPositionAbs * SIZE_SCALE_MULTIPLIER);
if (scaledSize < 0) {
scaledSize = 0;
}
matrix.setScale(scaledSize, scaledSize);
float moveX = 0;
float moveY = 0;
// Moving from right to left -- linear move since the scaling is done with respect to top-left corner of the view.
if (childPosition < 0) {
moveX = ((childPositionAbs - 1) * SIZE_SCALE_MULTIPLIER * width) + X_OFFSET;
moveX *= -1;
} else { // Moving from left to right -- sum of the previous positions' x displacements.
// X(n) = X(0) + X(1) + X(2) + ... + X(n-1)
for (int i = childPositionAbs; i > 0; i--) {
moveX += (i * SIZE_SCALE_MULTIPLIER * width);
}
moveX += X_OFFSET;
}
// Moving down y-axis is linear.
moveY = ((childPositionAbs * SIZE_SCALE_MULTIPLIER * height) / 2);
matrix.postTranslate(moveX, moveY);
// Scale alpha value.
final float alpha = (1.0f / childPositionAbs) * ALPHA_SCALE_MULTIPLIER;
t.setAlpha(alpha);
// Calculate new hit box. Since we moved the child, the hitbox is no longer lined up with the new child position.
final float newLeft = left + moveX;
final float newTop = top + moveY;
final float newRight = newLeft + (width * scaledSize);
final float newBottom = newTop + (height * scaledSize);
modifiedHitBox = new RectF(newLeft, newTop, newRight, newBottom);
} else {
modifiedHitBox = new RectF(left, top, right, bottom);
}
// update child hit box so you can tap within the child's boundary
((SetHitRectInterface) child).setHitRect(modifiedHitBox);
return true;
}
#Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
// Helps to smooth out jittering during scrolling.
// read more - http://www.unwesen.de/2011/04/17/android-jittery-scrolling-gallery/
final int viewsOnScreen = getLastVisiblePosition() - getFirstVisiblePosition();
if (viewsOnScreen <= 0) {
super.onLayout(changed, l, t, r, b);
}
}
private int mLastDrawnPosition;
#Override
protected int getChildDrawingOrder(int childCount, int i) {
//Reset the last position variable every time we are starting a new drawing loop
if (i == 0) {
mLastDrawnPosition = 0;
}
final int centerPosition = getSelectedItemPosition() - getFirstVisiblePosition();
if (i == childCount - 1) {
return centerPosition;
} else if (i >= centerPosition) {
mLastDrawnPosition++;
return childCount - mLastDrawnPosition;
} else {
return i;
}
}
}
File : /src/com/example/ScalingGalleryItemLayout.java
public class ScalingGalleryItemLayout extends LinearLayout implements SetHitRectInterface {
public ScalingGalleryItemLayout(Context context) {
super(context);
}
public ScalingGalleryItemLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public ScalingGalleryItemLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
private Rect mTransformedRect;
#Override
public void setHitRect(RectF newRect) {
if (newRect == null) {
return;
}
if (mTransformedRect == null) {
mTransformedRect = new Rect();
}
newRect.round(mTransformedRect);
}
#Override
public void getHitRect(Rect outRect) {
if (mTransformedRect == null) {
super.getHitRect(outRect);
} else {
outRect.set(mTransformedRect);
}
}
}
File : /res/layout/ScaledGalleryItemLayout.xml
<?xml version="1.0" encoding="utf-8"?>
<com.example.ScalingGalleryItemLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/gallery_item_layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:orientation="vertical"
android:padding="5dp" >
<ImageView
android:id="#+id/gallery_item_image"
android:layout_width="360px"
android:layout_height="210px"
android:layout_gravity="center"
android:antialias="true"
android:background="#drawable/gallery_item_button_selector"
android:cropToPadding="true"
android:padding="35dp"
android:scaleType="centerInside" />
<TextView
android:id="#+id/gallery_item_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:textColor="#drawable/white"
android:textSize="30sp" />
</com.example.ScalingGalleryItemLayout>

To keep the state of the animation after it is done, just do this on your animation:
youranim.setFillAfter(true);
Edit :
In my project, I use this method and i think, it's help you :
http://developer.sonymobile.com/wp/2011/04/12/how-to-take-advantage-of-the-pinch-to-zoom-feature-in-your-xperia%E2%84%A2-10-apps-part-1/

U can do Image Zoom pinch option for gallery also.
by using below code lines:
you can download the example.
https://github.com/alvinsj/android-image-gallery/downloads
I hope this example will help to u..if u have any queries ask me.....

This is solution
integrate gallery component in android with gesture-image library
gesture-imageView
And here is full sample code
SampleCode