Develop Reference

Animate layout change of bottom sheet

In my application I use a bottom sheet (from the support library) which works great. Now I would like to animate a layout change while the sheet is dragged up. For this I have created a subclass of BottomSheetCallback (this is normaly an inner class of a Fragment so not all objects used in this calss are initialized here):
public class MyBehavior extends BottomSheetBehavior.BottomSheetCallback {
Transition transition;
float lastOffset = 0;
Scene scene;
public PlayerBehavior() {
TransitionInflater inflater = TransitionInflater.from(getContext());
transition = inflater.inflateTransition(R.transition.player);
//transition.setDuration(300);
scene = fullLayout;
transition.setInterpolator(new Interpolator() {
#Override
public float getInterpolation(float v) {
return lastOffset;
}
});
}
#Override
public void onStateChanged(#NonNull View bottomSheet, int newState) {
if(newState == BottomSheetBehavior.STATE_DRAGGING) {
TransitionManager.go(scene, transition);
}
}
#Override
public void onSlide(View bottomSheet, final float slideOffset) {
scene = (slideOffset > lastOffset) ? smallLayout : fullLayout;
lastOffset = slideOffset;
}
}
As you can see I also created two Scene from different layout files and a custom Transition to animate between the scenes with the TransitionManager. My problem is that the Transition should be based on the slideOffset parameter (in range of 0-1) but the TransitionManager uses the Animation class in the background which is normally time based in Android.
I tried to create the custom Intapolator but this does not work properly. So how can I create a Transition which is based on an external variable and not on time?

Based on your description, I think you are trying to achieve something like google maps bottom sheet behaviour. The layout changes as the bottomsheet is dragged up.
If that is what you are trying to achieve then you don't need to enforce custom animations, as the bottomsheetdialog itself has those animation behaviour when incorporated inside a parent Coordinator Layout.
Here is a sample code of how I'm implementing the same behaviour. It also makes the FloatingActionButton invisible when the bottomsheet is dragged up to full screen size :
Create a bottomsheetdialog that you want to use inside your main layout
public class CustomBottomDialog extends BottomSheetDialogFragment {
String mSomeName;
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// if some arguments are passed from the calling activity
mSomeName = getArguments().getString("some_name");
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View bottomSheet = inflater.inflate(R.layout.bottomsheet_layout, container, false);
// initialise your bottomsheet_layout items here
TextView tvName = bottomSheet.findViewById(R.id.display_name);
tvName.setText(mSomeName);
tvName.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// do something here
((MainActivity)getActivity()).doSomething();
}
});
return bottomSheet;
}
}
bottomsheet_layout:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.FloatingActionButton
android:id="#+id/nav"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/navigation_tilt_grey"
app:backgroundTint="#color/colorAccent"
app:elevation="3dp"
app:fabSize="normal"
android:layout_marginEnd="#dimen/activity_horizontal_margin"
app:layout_anchor="#+id/live_dash"
app:layout_anchorGravity="top|right" />
<!--BottomSheet-->
<android.support.v4.widget.NestedScrollView
android:id="#+id/live_dash"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#F3F3F3"
android:clipToPadding="true"
app:layout_behavior="android.support.design.widget.BottomSheetBe
havior"
tools:layout_editor_absoluteY="150dp">
<!--Include your items here, the height of all items combined
will take the main screen layout size with animation-->
</android.support.v4.widget.NestedScrollView>
</android.support.design.widget.CoordinatorLayout>
Calling this BottomSheet from your activity:
public void notifyBottomSheet(String somename){
BottomSheetDialogFragment customDialogFragment = new CustomBottomDialog();
Bundle args = new Bundle();
args.putString("some_name", somename);
customDialogFragment.setArguments(args);
customDialogFragment.show(getSupportFragmentManager(), customDialogFragment.getTag());
customDialogFragment.setCancelable(false); // if you don't wish to hide
}
Hope this solves what you are trying to achieve.

To easily slide something off the bottom of the screen, you can use code such as:
final int activityHeight = findViewById(android.R.id.content).getHeight();
cardContainer.animate().yBy(activityHeight - cardContainer.getY()).setDuration(SLIDE_OUT_DURATION);
where cardContainer is the view you are trying to slide off the screen.
See this blog post for the complete example. Note that you can also use translationY instead of yBy. Another, more generic way of doing it is with this code:
public static ViewPropertyAnimator slideOutToBottom(Context ctx, View view) {
final int screenHeight = ctx.getResources().getDisplayMetrics().heightPixels;
int[] coords = new int[2];
view.getLocationOnScreen(coords);
return view.animate().translationY(screenHeight - coords[Y_INDEX]).setDuration(SLIDE_OUT_DURATION);
}
public static ViewPropertyAnimator slideInFromBottom(Context ctx, View view) {
final int screenHeight = ctx.getResources().getDisplayMetrics().heightPixels;
int[] coords = new int[2];
view.getLocationOnScreen(coords);
view.setTranslationY(screenHeight - coords[Y_INDEX]);
return view.animate().translationY(0).setDuration(SLIDE_IN_DURATION).setInterpolator(new OvershootInterpolator(1f));
}

## Translation Animation ##
<?xml version="1.0" encoding="utf-8"?>
<set
xmlns:android="http://schemas.android.com/apk/res/android"
android:interpolator="#android:anim/accelerate_decelerate_interpolator"
android:fillAfter="true"
>
<translate
android:fromYDelta="100%p"
android:toYDelta="-30%p"
android:duration="900" />
</set>
## Main Activity ##
#Override
protected void onResume() {
super.onResume();
Animation am= AnimationUtils.loadAnimation(this,R.anim.fadeout);
tv5.startAnimation(am);
Animation myanim= AnimationUtils.loadAnimation(this,R.anim.translate);
tv1.startAnimation(myanim);
myanim.setStartOffset(500);
Animation animation= AnimationUtils.loadAnimation(this,R.anim.translate);
animation.setStartOffset(1000);
tv2.startAnimation(animation);
Animation an= AnimationUtils.loadAnimation(this,R.anim.translate);
an.setStartOffset(1500);
tv3.startAnimation(an);
Animation ab= AnimationUtils.loadAnimation(this,R.anim.translate);
ab.setStartOffset(2000);
tv4.startAnimation(ab);
Animation ac= AnimationUtils.loadAnimation(this,R.anim.fadein);
ac.setStartOffset(2500);
btn1.startAnimation(ac);
}

I'm not sure if that is what you want but maybe instead of using transition, you can use the function animate() since with this function, you can change all things about your animation (time, visibility etc.).

Colors "flowing" in Android background

I have an application and I want to set it's background just like the Instagram's login page, the one with that "gradient colors". The colors are "moving" and it creats a cool effect. This is what I've tried so far:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_take_one);
colorFul = (RelativeLayout) findViewById(R.id.background);
GradientDrawable gd = new GradientDrawable(GradientDrawable.Orientation.TL_BR, new int[] {a,b});
gd.setCornerRadius(0f);
colorFul.setBackgroundDrawable(gd);
for(int i = 0; i<6; i++){
if(a == 0xff000000){
a = 0xff00ffff;
b = 0xff444444;
}else if(a == 0xff00ffff){
a = 0xff888888;
b = 0xff00ff00;
}else if(a == 0xff888888){
a = 0xffcccccc;
b = 0xffff00ff;
}else if(a==0xffcccccc){
a = 0xffff0000;
b = 0xffffffff;
}else if(a==0xffff0000){
a = 0xffffffff;
b = 0xffffff00;
}
System.out.println("||");
SystemClock.sleep(1000);
System.out.println(">");
}
}
But this doesn't work. What happens is that the collors don't change, it remains black until it gets to the last if and then the background become white and yellow(that are, respectively, the collors 0xffffffff and 0xffffff00), in gradient shape.
So, how can I do it? I don't care how it's done. Whether it is with GradientDrawable or using an animated gif as background(which didn't work, the gif remained still) or any other way. Thanks.
(This is what I want, the gif isn't that good but you can see how the background is changing it's color)

You could programmatically create something that changes the level of gradient over time, but that would require some effort. Alternatively, you could use a TransitionDrawable to fade between different gradients, which should produce a similar effect.
This can be implemented as follows:
<?xml version="1.0" encoding="UTF-8"?>
<transition xmlns:android="http://schemas.android.com/apk/res/android">
<!-- use two gradients, extending from opposite sides of the page-->
<item android:drawable="#drawable/gradientLeft" />
<item android:drawable="#drawable/gradientRight" />
</transition>
Then, you can activate the transition in code as follows:
TransitionDrawable transition = (TransitionDrawable) myLayout.getBackground();
transition.startTransition(1500);
Obviously you'll probably need to spend some time to get it looking the way you want, but this would be far easier than hard-coding a transitional algorithm!
COMPLETE AND WORKING CODE BELOW
So, I got my idea implemented, and it looks awesome! I didn't expect it would look this nice, but it's really cool. I was bored so decided I would shove the whole thing into a function so it's easier for you (and others) to utilize.
MainActivity.java
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ImageView image = (ImageView) findViewById(R.id.background);
Drawable backgrounds[] = new Drawable[3];
backgrounds[0] = ContextCompat.getDrawable(this, R.drawable.gradient1);
backgrounds[1] = ContextCompat.getDrawable(this, R.drawable.gradient2);
backgrounds[2] = ContextCompat.getDrawable(this, R.drawable.gradient3);
Crossfade(image, backgrounds, 10000);
}
public void Crossfade(final ImageView image, final Drawable layers[], final int speedInMs) {
class BackgroundGradientThread implements Runnable {
Context mainContext;
TransitionDrawable crossFader;
boolean first = true;
BackgroundGradientThread(Context c) {
mainContext = c;
}
public void run() {
Handler mHandler = new Handler(mainContext.getMainLooper());
boolean reverse = false;
while (true) {
if (!reverse) {
for (int i = 0; i < layers.length - 1; i++) {
Drawable tLayers[] = new Drawable[2];
tLayers[0] = layers[i];
tLayers[1] = layers[i + 1];
final TransitionDrawable tCrossFader = new TransitionDrawable(tLayers);
tCrossFader.setCrossFadeEnabled(true);
Runnable transitionRunnable = new Runnable() {
#Override
public void run() {
image.setImageDrawable(tCrossFader);
tCrossFader.startTransition(speedInMs);
}
};
mHandler.post(transitionRunnable);
try {
Thread.sleep(speedInMs);
} catch (Exception e) {
}
}
reverse = true;
}
else if (reverse) {
for (int i = layers.length - 1; i > 0; i--) {
Drawable tLayers[] = new Drawable[2];
tLayers[0] = layers[i];
tLayers[1] = layers[i - 1];
final TransitionDrawable tCrossFader = new TransitionDrawable(tLayers);
tCrossFader.setCrossFadeEnabled(true);
Runnable transitionRunnable = new Runnable() {
#Override
public void run() {
image.setImageDrawable(tCrossFader);
tCrossFader.startTransition(speedInMs);
}
};
mHandler.post(transitionRunnable);
try {
Thread.sleep(speedInMs);
} catch (Exception e) {
}
}
reverse = false;
}
}
}
}
Thread backgroundThread = new Thread(new BackgroundGradientThread(this));
backgroundThread.start();
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<ImageView android:id="#+id/background"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/gradient2"
android:scaleType="fitXY"/>
<TextView android:text="Hello World!" android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
gradient1/2.jpg
The primary function here creates a new thread that will automatically begin shifting the two images back and forth. Once one full transition has completed, it will then begin to fade back into the original image. It creates a really smooth and flowy effect most of the time, but may look weird when combining some gradient drawables. The function looks like this:
public void Crossfade(final ImageView image, final Drawable layers[], final int speedInMs)
1) final ImageView image
The first parameter should be the image object that is going to represent your background.
2) final Drawable layers[]
The second parameter takes an array of drawables, which should be two images like the ones I showed above. Playing around with different gradient images is fun, and quite interesting to watch how colors "flow". Be careful with your image sizes, though, as I had initially used massive images that had crashed the app or stuttered terribly in the animation process.
3) final int speedInMs
The last parameter simply represents the time (in milliseconds) it will take to completely transition from the first drawable to the second.
Here's a GIF of the result of these two images crossfading with a speed of 5000ms (note: I couldn't put a 10 second GIF on here showing the whole transition, but it's quite smooth!):
Github Link To Repository
EDIT 2: I updated the Github and the function on here, but I just added in multi-drawable support so an array of any number of images can be added in and it will cycle through them chronologically, until reaching the end at which point it will reverse through and repeat. Sexy.

Using personal SurfaceView on LinearLayout

I'm currently developing an Android App, using a personal SurfaceView and double buffering. However I'm facing a little problem with my code.
In one hand I have an xml view, based on LinearLayout hierarchy. When I instantiate my activity, I set my contentView on this xml. The problem is then that my double buffering don't works anymore. Thread is running but nothing is displayed.
In the other hand, I set my contentView with a new personal SurfaveView element and display works fine. But of course, I cannot access anymore to the other elements of my LinearLayout.
Actually, I would like to set my contentView on my xml view AND keep my display working.
I hope I was clear enough, thank you for your answers!
Here is my activity:
public class MainController extends Activity {
#Override
protected void onCreate(final Bundle p_savedInstanceState) {
super.onCreate(p_savedInstanceState);
setContentView(R.layout.main_controller_activity);
this.drawableView = (MCustomDrawableView) findViewById(R.id.drawingBox);
...
}
...
}
My surface view:
public class MCustomDrawableView extends SurfaceView {
public MCustomDrawableView(Context p_context, AttributeSet p_attributes) {
super(p_context, p_attributes);
this.getHolder().addCallback(new SurfaceHolder.Callback() {
#Override
public void surfaceCreated(final SurfaceHolder p_holder) {
try {
// Instantiating a new thread
thread = new MBufferingThread(getInstance());
thread.start();
} catch (Exception exception) {
exception.printStackTrace();
}
}
#Override
public void surfaceChanged(final SurfaceHolder p_holder, int p_format, int p_width, int p_height) {...}
#Override
public void surfaceDestroyed(final SurfaceHolder p_holder) {...}
});
// Setup drawing options
setupDrawing();
}
...
}
And my xml view:
<LinearLayout 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:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
android:background="#color/app_background"
tools:context=".MainController">
<com.iskn.calligraphy.models.draw.MCustomDrawableView
android:id="#+id/drawingBox"
style="#style/DrawingBox" />
<SeekBar
android:id="#+id/brushSize"
style="#style/SizeSeekBar" />
<SeekBar
android:id="#+id/brushOpacity"
style="#style/OpacitySeekBar" />
</LinearLayout>
EDIT:
After further researches and analyses, it appears clearly that:
setContentView(R.layout.main_controller_activity): in this case I get all the elements from my activity, but the MCustomDrawableView display nothing.
setContentView(new MCustomDrawableView(getApplicationContext())): on that case, MCustomDrawableView is working well (it displays what I want), but I don't have the others View from my main_controller_activity
In both cases:
my thread is running and works well.
my drawing function is called as well, with the holder.lockCanvas() and holder.unlockCanvasAndPost(bufferCanvas) methods.

Well, I found a functionnal solution :
I think the problem was coming from the MCustomDrawableView initialization . I created a new instance of that class from the onCreate method , and not from the xml file . Then, I set it to the contentView:
protected void onCreate(Bundle p_savedInstanceState) {
super.onCreate(p_savedInstanceState);
setContentView(R.layout.main_controller_activity);
// Instantiate drawable object & set style properties
this.drawableView = new MCustomDrawableView(getApplicationContext());
FrameLayout.LayoutParams style = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
FrameLayout.LayoutParams.MATCH_PARENT);
// Add the drawable view to the main_activity
addContentView(this.drawableView, style);
}
But this way raises a new problem. The added view is on the top, which means that all the others View are hided. I solved this with bringToBack(this.drawableView) below method:
private void bringToBack(View p_view) {
// Get parent from the current view
ViewGroup viewGroup = ((ViewGroup) p_view.getParent());
int childrenCount = viewGroup.indexOfChild(p_view);
for(int cpt = 0; cpt < childrenCount; cpt++) {
// Move the child to the top
viewGroup.bringChildToFront(viewGroup.getChildAt(cpt));
}
}
It brings back the provided view to the background position. I also had to set the LinearLayout's alpha to 0.
I'm still open to other solutions!

Integrate Unity3d view into Android activity

I'm currently working on a small AR app for Android and am facing the problem of integrating Unity3d into an activity. The requirements indicate that I need to be able to present some Android UI - e.g. menus and an action bar - and a camera view that will display a model created in Unity3d when the target is detected.
I found a link that helped me a lot: Unity3d forums. One of the users there asked the same question I have now but never got any proper answer -that's why I'm posting here.
Problem:
I got a small Unity3d project that is essentially a white cube and am trying to display it in one of my Android activities. The model looks fine when activity doesn't have setContentView() in its onCreate() method but then I can't specify my layout in an XML file.
When I do add the setContentView() method, I can see the cube but it's very small and there doesn't seem to be any way of actually making it change its size.
The XML file:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/unityView"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
</FrameLayout>
1st version of the activity implementation:
public class HomeActivity extends UnityPlayerActivity {
UnityPlayer unityPlayer;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
}
And the resulting screenshot:
2nd version of the activity implementation:
public class HomeActivity extends UnityPlayerActivity {
UnityPlayer unityPlayer;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
unityPlayer = new UnityPlayer(this);
int glesMode = unityPlayer.getSettings().getInt("gles_mode", 1);
unityPlayer.init(glesMode, false);
FrameLayout layout = (FrameLayout) findViewById(R.id.unityView);
LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
layout.addView(unityPlayer.getView(), 0, lp);
}
#Override
public void onWindowFocusChanged(boolean hasFocus) {
super.onWindowFocusChanged(hasFocus);
unityPlayer.windowFocusChanged(hasFocus);
}
}
And the resulting screenshot:
Could anyone explain to me why that is and how to fix it?

While I still don't know why it works like that, I've found a way of fixing it.
Instead of simply using setContentView() in onCreate(), extend onResume() and in that method recursively look through all the available views to find the parent view of the UnityPlayer object. Once that's found, layouts and other views can be inflated and added to that parent view.
Here's the link with a code example - I've used this to make my app work: https://developer.vuforia.com/resources/dev-guide/extending-unity-android-activity-and-adding-custom-views-eclipse
Edit: Here's a code snippet showing my solution.
#Override
public void onResume() {
super.onResume();
if (unityPlayer == null) {
View rootView = findViewById(android.R.id.content);
unityPlayer = findUnityPlayerView(rootView);
if (unityPlayer != null) {
ViewGroup unityPlayerParentView = (ViewGroup)(unityPlayer.getParent());
View mainHomeView = getLayoutInflater().inflate(R.layout.activity_main, null);
LayoutParams layoutParams = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
unityPlayerParentView.addView(mainHomeView, layoutParams);
}
}
}
and
private UnityPlayer findUnityPlayerView(View view) {
if (view instanceof UnityPlayer) {
return (UnityPlayer) view;
}
if (view instanceof ViewGroup) {
ViewGroup childrenViews = (ViewGroup) view;
for (int i = 0; i < childrenViews.getChildCount(); i++) {
UnityPlayer foundView = findUnityPlayerView(childrenViews.getChildAt(i));
if (foundView != null) {
return foundView;
}
}
}
return null;
}

activity screen containing googlemap v2 is black when loading polygons

I am using the code from google maps v2 to draw polygons on loading maps v2 .It loads 300+ polygons in 5 secs but it shows black screen till 5 secs and does not display anything on the screen.How do I show map or should I display loading.. msg till it displays the maps ??I really appreciate any help .I tried many ways but still see black screen as its loading polygon onthe main thread.Thanks in Advance.
LatLng allLatLng= new LatLng((lat1),(long1));
all.add(allLatLng);
polygon = googleMap.addPolygon(new PolygonOptions()
.addAll(all)
.fillColor(Color.Yellow)
.strokeColor(Color.blue)
);

Example to go with the comments
//in onCreate
String json_string = getJsonStringStuff();
new AsyncTask<String, Void, List<List<LatLng>>>() {
#Override protected List<List<LatLng>> doInBackground(String... params) {
String json = params[0];
List<List<LatLng>> mLatLngList = new ArrayList<ArrayList<LatLng>>();
// Parse the json into the list
return mLatLngList;
}
#Override protected void onPostExecute(List<List<LatLng>> result) {
drawPolygonsToMap(result);
}
}.execute(json_string);

Use This to prevent black background
<fragment
android:id="#+id/location_map_fragment"
android:name="com.app.appname.TransparentSupportMapFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/white" />
/**
*
* To prevent black background of map in ScrollView
*
*/
public class TransparentSupportMapFragment extends SupportMapFragment {
public TransparentSupportMapFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup view, Bundle savedInstance) {
View layout = super.onCreateView(inflater, view, savedInstance);
FrameLayout frameLayout = new FrameLayout(getActivity());
frameLayout.setBackgroundColor(getResources().getColor(android.R.color.transparent));
((ViewGroup) layout).addView(frameLayout,
new ViewGroup.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
return layout;
}
public static TransparentSupportMapFragment newInstance(String abc) {
TransparentSupportMapFragment tsf = new TransparentSupportMapFragment();
return tsf;
}
}