Develop Reference

Make the bitmap get over ImageView borders

I'm running a rotation animation on a ImageView. The thing is the bitmap has been cut to fit exactly the ImageView. So when it rotate, it doesn't cover completely the ImageView as well as the screen.
This is what I want
And this is what happened
xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".fragments.LevelCompletedFragment">
<RelativeLayout
android:id="#+id/vgBackground"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#3f5d68"
android:alpha="1">
</RelativeLayout>
<ImageView
android:id="#+id/ivStarburst"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:adjustViewBounds="true"
android:scaleType="centerCrop"
android:src="#drawable/star" />
</FrameLayout>
Run animation
Animation shake = AnimationUtils.loadAnimation(mContext, R.anim.clockwise_rotation);
**ivStarburst.startAnimation(shake);
Edit: After following the solution by #deadfish the animation run correctly only when I open the fragment in onCreate() in MainActivity. If I trigger the fragment in onClick() method, it doesn't work.
MainActivity.java
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
btn.setOnClickListener(this);
}
#Override
public void onClick(View v) {
MainFragment frgm = new MainFragment ();
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, frgm).commit();
}

You almost did it but forget two things:
setting ImageView width and height as match_layout will match only to the parent's border. You must set custom dimenstion so when You center image, it will fill the whole view.
during image's rotation when the image reaches degree 45 we can notice the image doesn't fill the whole view. Why? Try put two rectangles on themself and then rotate one of them by 45 degree. Here is the result. According to definition of square, it's diagonal value is bigger than one of the sides of a square. So we must cover this.
Here is the solution.
we set custom dimension for ImageView basing on the longest side of the screen
we rewrite width to use diagonal width of square instead of single side
Most of the code is the same as Yours. I used fragment to show the sample.
//MainActivity part
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
this.<Button>findViewById(R.id.btn).setOnClickListener(this);
}
#Override
public void onClick(View v) {
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.container, MainFragment.newInstance())
.commit();
}
}
// Fragment part
public class MainFragment extends Fragment {
public static MainFragment newInstance() {
return new MainFragment();
}
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.main_fragment, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
ImageView imageView = Objects.requireNonNull(view).findViewById(R.id.imageView);
// Manually set image for ImageView
setImageForView(imageView, R.drawable.star);
// Turn ImageView to square where a = Max(Screen.width, Screen.height)
changeDimensionToSquareForView(imageView);
// Start rotations
animateRotation(imageView);
}
private void changeDimensionToSquareForView(ImageView imageView) {
DisplayMetrics displayMetrics = Resources.getSystem().getDisplayMetrics();
double maxWidth = Math.max(displayMetrics.widthPixels, displayMetrics.heightPixels);
//calc diagonal line, x = a * sqrt(2)
maxWidth = (maxWidth * (Math.sqrt(2)));
imageView.setLayoutParams(new FrameLayout.LayoutParams((int) maxWidth, (int) maxWidth, Gravity.CENTER));
}
private void setImageForView(ImageView imageView, #DrawableRes int imageRes) {
Context context = imageView.getContext();
imageView.setImageDrawable(context.getResources().getDrawable(imageRes, context.getTheme()));
}
// Call this method in onClick method
public void animateRotation(ImageView imageView) {
Context context = imageView.getContext();
Animation shake = AnimationUtils.loadAnimation(context, R.anim.clockwise_rotation);
imageView.startAnimation(shake);
}
}
Here is the layout of fragment:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.main.MainFragment">
<ImageView
android:id="#+id/imageView"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:src="#drawable/star" />
</FrameLayout>
Here is the animation xml:
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:duration="15000"
android:fromDegrees="0"
android:interpolator="#android:anim/linear_interpolator"
android:pivotX="50%"
android:pivotY="50%"
android:startOffset="0"
android:toDegrees="360" />
Here is the result:

RecyclerView in DialogFragment not scrolling

I have a RecyclerView in a DialogFragment. Both the Dialog fragment and recyclerview show though when the recyclerview fills beyond the view capacity it does not scroll.
?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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:tag="FoodMenuTag"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.example.android.cop1803.MainActivity">
<View
android:id="#+id/divider3"
android:layout_width="1184dp"
android:layout_height="1dp"
android:layout_marginTop="#dimen/MarginTop_PDF_dividers"
android:layout_marginBottom="#dimen/MarginTop_PDF_dividers"
android:background="?android:attr/listDivider"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="#+id/kCal"
tools:layout_editor_absoluteX="8dp" />
<com.example.android.cop1803.MyRecyclerView
android:id="#+id/recycler_menuview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="vertical"
app:layout_constraintTop_toBottomOf="#id/divider3"
/>
Here's my Dialog Fragment:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.recyclerview_menu, container, false);
mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_menuview);
return view;
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
Bundle args = getArguments();
if(args != null) {
cartList = args.getParcelableArrayList("key");
MenuDialogFragmentAdapter adapter = new
MenuDialogFragmentAdapter(this.getActivity(), cartList);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setAdapter(adapter);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
}
}
#Override
public void onResume() {
// Get existing layout params for the window
ViewGroup.LayoutParams params = getDialog().getWindow().getAttributes();
// Assign window properties to fill the parent
params.width = WindowManager.LayoutParams.MATCH_PARENT;
params.height = WindowManager.LayoutParams.MATCH_PARENT;
getDialog().getWindow().setAttributes((android.view.WindowManager.LayoutParams) params);
// Call super onResume after sizing
super.onResume();}
Any help with getting this to work is much appreciated.
thanks,
Jim

It turned out I was not accounting for the full height of my recycler view. So it was actually working but the height was extending it beyond the bottom boundary. Once I made a few adjustments to the height it worked. Here's the XML that on landed on.
<com.example.android.cop1803.MyRecyclerView
android:id="#+id/recycler_menuview"
android:layout_width="match_parent"
android:layout_height="350dp"
android:layout_marginStart="8dp"
android:layout_marginBottom="8dp"
android:scrollbars="vertical"
app:layout_constraintVertical_bias="0.01"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/divider3" />
I don't like the height being a fixed value so I'll likely change via code.
thanks,
Jim

try adding nested scrolling to the recyclerview, see if its works.
recyclerView.setNestedScrollingEnabled(true);

Showing an overlay in Android

My idea was to have a simple layout for a normal notification and a dialog control for the pop up with animation. Since the pop up needs to be at the point on which the user clicks, I wanted to write a custom DialogueView extending the Dialog class, within which I determine the anchor point.
This is what I have done so far:
Design of the layout without the pop up:
pre_session_view_layout.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:verizon="http://schemas.android.com/apk/res-auto"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:id="#+id/preSessionLayout">
<TextView
android:id="#id/verizon_sd_caption"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_toLeftOf="#id/verizon_sd_empty_view"
android:layout_toRightOf="#id/verizon_sd_icon"
android:gravity="center|center_horizontal"
android:paddingLeft="5dp"
android:paddingRight="10dp"
android:textColor="#android:color/white"
android:textSize="18sp"></TextView>
<demo.notification.verizon.com.notificationdemo.ResizableImageView
android:id="#id/verizon_sd_icon"
android:layout_width="36dp"
android:layout_height="34dp"
android:paddingLeft="6dp"
android:paddingRight="6dp"
android:paddingTop="6dp"
android:paddingBottom="6dp"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:scaleType="centerInside" />
<!--android:src="#drawable/_fw_prenotify" -->
<ImageView
android:id="#id/verizon_sd_empty_view"
android:layout_width="1dp"
android:layout_height="match_parent"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:visibility="invisible"
/>
</RelativeLayout>
The design of the overlay:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="240dp"
android:layout_height="110dp"
android:orientation="vertical"
android:id="#+id/overlayLayout">
<ImageView
android:id="#+id/imageView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/notification_bg_green"/>
</RelativeLayout>
PressionView.java: ( Java file for showing the normal and pop up notification)
I am only giving the code snippet for showing the pop up as an overlay.This function gets called when the user clicks on the bee icon.
private void showOverLay(){
final ConfirmBox dialog = new ConfirmBox(this.bannerThumb);
LayoutInflater inflater = LayoutInflater.from(ctx);
dialog.onCreateView(inflater,this.relLayout,null);
}
Finally the custom Dialogue is as follows:
public class ConfirmBox extends DialogFragment {
private View source;
public ConfirmBox() {
}
public ConfirmBox(View source) {
this.source = source;
}
public static ConfirmBox newInstance(View source) {
return new ConfirmBox(source);
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setStyle(STYLE_NO_FRAME, R.style.AppTheme);
}
#Override
public void onStart() {
super.onStart();
// Less dimmed background; see http://stackoverflow.com/q/13822842/56285
Window window = getDialog().getWindow();
WindowManager.LayoutParams params = window.getAttributes();
params.dimAmount = 0.2f; // dim only a little bit
window.setAttributes(params);
// Transparent background; see http://stackoverflow.com/q/15007272/56285
// (Needed to make dialog's alpha shadow look good)
window.setBackgroundDrawableResource(android.R.color.transparent);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Put your dialog layout in R.layout.view_confirm_box
View view = inflater.inflate(R.layout.overlay_view, container, false);
// Initialise what you need; set e.g. button texts and listeners, etc.
// ...
setDialogPosition();
return view;
}
/**
* Try to position this dialog next to "source" view
*/
private void setDialogPosition() {
if (source == null) {
return; // Leave the dialog in default position
}
// Find out location of source component on screen
// see http://stackoverflow.com/a/6798093/56285
int[] location = new int[2];
source.getLocationOnScreen(location);
int sourceX = location[0];
int sourceY = location[1];
Window window = getDialog().getWindow();
// set "origin" to top left corner
window.setGravity(Gravity.TOP| Gravity.LEFT);
WindowManager.LayoutParams params = window.getAttributes();
// Just an example; edit to suit your needs.
params.x = sourceX - dpToPx(110); // about half of confirm button size left of source view
params.y = sourceY - dpToPx(80); // above source view
window.setAttributes(params);
}
public int dpToPx(float valueInDp) {
DisplayMetrics metrics = getActivity().getResources().getDisplayMetrics();
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, valueInDp, metrics);
}
}
I can show the normal notification. But for the pop up , the approach which I have taken,I get a null pointer exception in the showOverLay() method.
More specifically on the line:
Window window = getDialog().getWindow();
within the getDialoguePosition() of the custom Dialogueclass.
Can someone kindly help me on this? If reqd I can share the full code for the PresessionView.java file as well.
I think I am making some mistake in calling the custom Dialogue class.
Thanks.

You show the dialog fragment incorrect.
Please use dialog.show(...). Also please ensure that you're bannerThumb, ctx, and relLayout are not null.
private void showOverLay(){
final ConfirmBox dialog = new ConfirmBox(this.bannerThumb);
LayoutInflater inflater = LayoutInflater.from(ctx); //Ensure ctx is not NULL
dialog.show(getSupportFragmentManager(), "yourtitle");
}

How to create a vertical pagination with a fixed view

I have 4 fragments and I want to create a sort of vertical viewpager but I need to keep visible a view of the previous page.
In more details:
Fragment A have a TextView (TV1) on the bottom and other views.
Fragment B have a TextView (TV2) on the bottom and other views.
Fragment C have a TextView (TV3) on the bottom and other views.
I start my Activity, Fragment A occupies the entire layout.
Click on a button -> Fragment A slides up and Fragment B appears but TV1 should still be visibile and fixed on the top of the screen.
Click on a button -> Fragment B slides up and Fragment C appears but TV2 should still be visibile and fixed on the top of the screen (TV2 should replace TV1)...
If I click on TV2 the Fragment B will reappear above the Fragment B.
How can I obtain this behavior?

I finally managed to implement something similar to what you ask about. Here's how it looks:
It might a bit hacky, though that's how I archive it:
First, I needed some TvFragment:
public class TvFragment extends android.support.v4.app.Fragment {
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.tv_fragment, container, false);
TextView textView = (TextView)rootView.findViewById(R.id.tvTextView);
textView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
((OnScrollChanged)getActivity()).onScroll(TvFragment.this);
}
});
return rootView;
}
public void display(int height, String tvTitle, int backgroundColor) {
if (getView() == null) {
return;
}
ViewGroup.LayoutParams params = getView().getLayoutParams();
params.height = height;
getView().setLayoutParams(params);
TextView textView = (TextView)getView().findViewById(R.id.tvTextView);
textView.setText(tvTitle);
getView().setBackgroundColor(backgroundColor);
}
}
And it's tv_fragment.xml:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_gravity="bottom"
android:id="#+id/tvTextView"
android:gravity="center"
android:textColor="#FFFFFF"
android:textSize="24sp"
android:background="#drawable/textview_backgroud_selector"
android:padding="8dp"
android:layout_margin="#dimen/tv_button_margin"
android:layout_width="match_parent"
android:layout_height="#dimen/tv_button_height" />
</FrameLayout>
And then we need to fill the Activity with our Fragment
Then, we need to have an adapter to fill it with our fragments:
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/scrollView"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<fragment
android:id="#+id/fragmentA"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:name="klogi.com.verticalpagination.TvFragment"/>
<fragment
android:id="#+id/fragmentB"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:name="klogi.com.verticalpagination.TvFragment"/>
<fragment
android:id="#+id/fragmentC"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:name="klogi.com.verticalpagination.TvFragment"/>
</LinearLayout>
</ScrollView>
I.e. we keep all three fragments in one ScrollView.
Small helper interface to communicate between fragment and activity:
public interface OnScrollChanged {
void onScroll(Fragment fragment);
}
And last piece is MainActivity class:
public class MainActivity extends AppCompatActivity implements OnScrollChanged {
TvFragment fragmentA;
TvFragment fragmentB;
TvFragment fragmentC;
int bigFragmentHeight;
int smallFragmentHeight;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportActionBar().hide();
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
bigFragmentHeight = metrics.heightPixels - getStatusBarHeight();
smallFragmentHeight = bigFragmentHeight - getResources().getDimensionPixelSize(R.dimen.tv_button_height) - 2 * getResources().getDimensionPixelSize(R.dimen.tv_button_margin);
fragmentA = (TvFragment)getSupportFragmentManager().findFragmentById(R.id.fragmentA);
fragmentA.display(bigFragmentHeight, "TV1", Color.BLUE);
fragmentB = (TvFragment)getSupportFragmentManager().findFragmentById(R.id.fragmentB);
fragmentB.display(smallFragmentHeight, "TV2", Color.RED);
fragmentC = (TvFragment)getSupportFragmentManager().findFragmentById(R.id.fragmentC);
fragmentC.display(smallFragmentHeight, "TV3", Color.YELLOW);
ScrollView scrollView = (ScrollView)findViewById(R.id.scrollView);
scrollView.setOnTouchListener( new View.OnTouchListener(){
#Override
public boolean onTouch(View v, MotionEvent event) {
return true;
}
});
}
public int getStatusBarHeight() {
int result = 0;
int resourceId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resourceId > 0) {
result = getResources().getDimensionPixelSize(resourceId);
}
return result;
}
#Override
public void onScroll(Fragment fragment) {
ScrollView scrollView = (ScrollView)findViewById(R.id.scrollView);
int currentScroll = scrollView.getScrollY();
if (fragment.equals(fragmentA)) {
if (currentScroll == 0) {
scrollView.smoothScrollTo(0, smallFragmentHeight);
} else {
scrollView.smoothScrollTo(0, 0);
}
} else if (fragment.equals(fragmentB)) {
if (currentScroll == smallFragmentHeight) {
scrollView.smoothScrollTo(0, smallFragmentHeight + bigFragmentHeight);
} else {
scrollView.smoothScrollTo(0, smallFragmentHeight);
}
} else if (fragment.equals(fragmentC)) {
// do nothing
}
}
}
What am I doing here - is to disabling "normal" scrolling of the ScrollView and depends on which fragment's button has been clicked - smooth scrolling up or down.
I used also this resources:
dimens:
<resources>
<dimen name="tv_button_height">48dp</dimen>
<dimen name="tv_button_margin">8dp</dimen>
</resources>
colors:
<resources>
<color name="textview_backgroud">#AAAAAA</color>
<color name="textview_backgroud_pressed">#777777</color>
</resources>
and textview_backgroud_selector:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:color="#color/textview_backgroud_pressed"/>
<item android:color="#color/textview_backgroud"/>
</selector>
I've uploaded the complete project into my dropbox - feel free to check it out
That's it! I hope, it helps

Android measuring an imageview

I need to measure the width of an ImageView, but when i measure it after setting
android:adjustViewBounds on the ImageView the measuredWidth is incorrect...
What am i doing wrong and how should i fix this?
My layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#drawable/lines2"
android:orientation="vertical"
android:weightSum="917">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="143">
<RelativeLayout
android:id="#+id/rectangleLayout"
android:background="#drawable/customborder"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<ImageView
android:id="#+id/circle"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:background="#drawable/circle"
android:src="#drawable/circle"
/>
</RelativeLayout>
public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
view = inflater.Inflate (Resource.Layout.pager1Fragment, container, false);
rectangleLayout = view.FindViewById<ViewGroup> (Resource.Id.rectangleLayout);
circle = view.FindViewById<ImageView> (Resource.Id.circle);
circle.Measure ( Android.Views.View.MeasureSpec.MakeMeasureSpec(0, MeasureSpecMode.Unspecified),
Android.Views.View.MeasureSpec.MakeMeasureSpec(0, MeasureSpecMode.Unspecified));
Initialize ();
return view;
}
public void Initialize ()
{
var rectanglePadding = (int)((double)circle.MeasuredWidth / 2d);
//measuredWidth is wrong when adjustviewbounds is set
Console.WriteLine ("padding " + rectanglePadding);
RelativeLayout.LayoutParams p = new RelativeLayout.LayoutParams (RelativeLayout.LayoutParams.MatchParent, RelativeLayout.LayoutParams.MatchParent);
p.LeftMargin = rectanglePadding;
rectangleLayout.LayoutParameters = p;
}

Ok getting View asap when my fragment is created.
ImageView Example = (ImageView) parentview.findViewById(R.id.Example);
Example.getViewTreeObserver().addOnGlobalLayoutListener(
new ViewTreeObserver.OnGlobalLayoutListener() {
#SuppressWarnings("deprecation")
#Override
public void onGlobalLayout() {
Example.getViewTreeObserver().removeGlobalOnLayoutListener(this);
int width = Example.getWidth() <--- this gives you width.
}
});
Just convert your code to that and your set.