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How to implement Lollipop activity transitions with views

I have a custom view, that I replace with different view. Part of the elements on the new view are connected. Like the user image.
I want to use the same animation effect as in Lollipop activities transition between my views.
Is there any way to achieve this?

Animate part of Activity Launch

Is it possible to animate part of an activity launch?
I am not wanting my action bar to animate, however the rest of the view should slide in.
I have tried using a Gallery for this, however I have not been able to animate the gallery while programatically setting the selected view. This is because the gallery does not load more than the currently displayed view and its immediate adjacent views.

When you can use the viewflipper for this. Which shows 1 child at a time. You can set a IN and OUT animation for the views. So when you set the activew view index animations will be applied.

GridView in android

I have a gridview of images in android. When i click any item on it, i want to show a new set of items over it. This is the screen shot .
Can this be done using gridview? Also what should be the type of view which must come over the gridview? The background should become preferably faded.

I am not so sure if you can achieve the second view using a grid view. In the grid view AFAIK you don't have any option of specifying the location of the grid elements. It just arranges it from left to right and wraps around.
But here is how I would do it -
First view can be done using the grid
view, as you already know/done.
For the second view since you want the the first view to remain in the background, there are two ways to go about this -
First option
You can use a dialog, you can create your own custom dialog which has makes it translucent.
In this custom dialog you can add further elements like images.Custom dialog example. For details on how to make it translucent you can look the sample app in android sdk.
Second option -
Use a layoutInflater. Put all your views into it.
You can display one view on top of another using the visibility attribute of the view. Layout Inflater

Struggling with view animations

I've got an absolute layout. In that layout is a custom view that takes up the left 3rd of the screen. I put a button in the layout that I want to cause the custom view to slide on and off of the screen. I've tried using animation resources (translates... "slidein" and "slideout") and the function startAnimation on the custom view, but I can't get the behavior I am looking for.
OK... I start with the custom view visible and in onCreate I find the view and animate it off screen using my slideout animation. That works fine. I figured out that I need to set "fillAfter" in the animation so that the custom view stays off screen.
Now, when I press my button I want to cause the custom view to slide back on the screen, so I trigger my slidein animation using startAnimation again but with slidein. BUT... that causes the view to first jump back to its original position AND THEN slide to the right... causing it to finish in the middle of the screen.
How do I get the animation to use the view's current position as the animation starting position, not its original position?
Thanks

I also experienced the flicker described in this question. My solution was to use the improved Honeycomb animation APIs. There is a convenient library that ports these all the way back to Android 1.0:
http://nineoldandroids.com/
For more on Honeycomb Animation APIs see:
http://android-developers.blogspot.com/2011/02/animation-in-honeycomb.html
In my case I had 2 overlapped LinearLayouts inside a RelativeLayout. I wanted to slide the top LinearLayout off the screen and reveal the bottom LinearLayout below. Then I wanted to slide to top LinearLayout back on screen to its original position so the top layout covered the bottom layout again. Using the old animation APIs I was seeing a flicker before the second animation (offscreen -> onscreen) was starting.
With the new APIs this task turned out to be trivial:
// Slide out (add to button handler)
ObjectAnimator.ofFloat(mTopLayout, "translationY", mTopLayout.getHeight()).start();
// Slide back in (add to button handler)
ObjectAnimator.ofFloat(mTopLayout, "translationY", 0).start();
The Honeycomb Animation APIs actually move objects around on the screen (rather than pretending to move them like the older animation APIs), so there is no need to fool around with filleAfter, fillBefore, etc.

Look into setting the fillAfter property to keep the end animation state

Creating autohide custom view in android

I am working on creating a custom view in android. I want to create an autohide custom view control.
This control will be holding other UI elements mostly buttons or icons. It has a small button which is mandatory, clicking which will slide the control in or out thus changing its visibility.
one should be able to add other buttons or icons to this control
The control can be placed only at the borders, which needs to be specified while creating the view.
I don't know how to start with it
Should I be extending the View class or ViewGroup class.

have a look at this
and then you have to add a dynamic layout to this drawer

I used a RelativeLayout and added a Button to the View.
When I call expandView() or collapseView(), I call mybutton.setVisibility() and let RelativeLayout know it has changed with this.requestLayout().