Develop Reference

Create custom AppBarLayout child with minimum height?

I want to create a custom view that will be a child of an AppBarLayout. I need this view to collapse partially as I scroll up, but not completely. It will have a minimum height and stay fixed to the top of the AppBarLayout in it's small size mode and then expand back to it's large size mode when the view is scrolled back down.
I've spent a lot of time looking through the source of the AppBarLayout and CoordinatorLayout, and so far I don't see a way to do what I want. It looks like children of AppBarLayout must either stay visible or disappear completely when the view is scrolled up.
Can anyone suggest a way to create a child of an AppBarLayout that will behave this way?
Thank you

Here's the recipe:
If you set android:minHeight, the AppBarLayout will respect that value by not scrolling beyond the point that would make your component smaller. So your XML layout might be something like this:
<com.example.CustomCollapsingLayout
android:layout_width="match_parent"
android:layout_height="320dp"
android:minHeight="108dp"
android:fitsSystemWindows="true"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
Next you want to have your class register an OnOffsetChangedListener with the parent AppBarLayout. Your component will get events as the app bar is scrolled so that you know how to configure your view.
class OnOffsetChangedListener implements AppBarLayout.OnOffsetChangedListener {
#Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
final int scrollRange = appBarLayout.getTotalScrollRange();
float offsetFactor = (float) (-verticalOffset) / (float) scrollRange;
...
This shows you how to find the total scroll range and then find the ratio between the total scroll range and the current scroll position i.e. where the app bar is in its scroll.
You should do what CollapsingToolbarLayout does; override onAttachedToWindow and add the listener there:
// Add an OnOffsetChangedListener if possible
final ViewParent parent = getParent();
if (parent instanceof AppBarLayout) {
if (mOnOffsetChangedListener == null) {
mOnOffsetChangedListener = new OnOffsetChangedListener();
}
((AppBarLayout) parent).addOnOffsetChangedListener(mOnOffsetChangedListener);
}
Take a look at the source code for CollapsingToolbarLayout as it will give you some ideas. Your view needs to do a lot of the same things.
You can also look at my sample project that has an image that scales and moves as the toolbar is scrolled: https://github.com/klarson2/Collapsing-Image

Android: Programmatically Collapse and expand the CollapsingToolbarLayout

I have ImageView and TabLayout(4 Tabs) inside CollapsingToolbarLayout, Now i want to collapse Appbar when clicking on Tabs(2,3,4) and for first tab it should work normally(as per scrolling). Is there a way to expand and collapse Appbar programmatically?
however i have seen solution, appBarLayout.setExpanded(false) collapses Appbar but again it is able to drag down. i want to prevent AppBar Expansion until Tab 1 is clicked?

Use mAppBarLayout.setExpanded(true) to expand Toolbar and use mAppBarLayout.setExpanded(false) to collapse Toolbar.
If you want to prevent CollapsingToolbarLayout expansion until
Tab 1 is clicked then you should use mAppBarLayout.setLayoutParams(params) programmatically to change
CollapsingToolbarLayout height.
Collapse: Use when Tabs(2,3,4) clicked
CoordinatorLayout.LayoutParams params =(CoordinatorLayout.LayoutParams) mAppBarLayout.getLayoutParams();
params.height = 3*80; // COLLAPSED_HEIGHT
mAppBarLayout.setLayoutParams(params);
mAppBarLayout.setExpanded(false);
Expand: Use when Tab 1 clicked
CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) mAppBarLayout.getLayoutParams();
params.height = 3*200; // EXPANDED_HEIGHT
mAppBarLayout.setLayoutParams(params);
mAppBarLayout.setExpanded(true);
Hope this will help you~

Hide/Show Toolbar programmatically on CoordinatorLayout

When I scroll my RecycleView ToolBar hide or show (with animation).
How I can return ToolBar back programmatically?

If your toolbar is inside an AppBarLayout which is probably inside your CoordinatorLayout then something like this should work.
AppBarLayout appBarLayout = (AppBarLayout)findViewById(R.id.appBar);
appBarLayout.setExpanded(true, true);
Or to collapse it
AppBarLayout appBarLayout = (AppBarLayout)findViewById(R.id.appBar);
appBarLayout.setExpanded(false, true);
Here is the definition
setExpanded(boolean expanded, boolean animate)
Take note that this method is available from v23 of the support library, here is some documentation for reference, the key thing to note is "As with AppBarLayout's scrolling, this method relies on this layout being a direct child of a CoordinatorLayout."

Is that what you looking for?
Toolbar toolbar = findViewById(R.id.toolbar); // or however you need to do it for your code
AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) toolbar.getLayoutParams();
params.setScrollFlags(0); // clear all scroll flags
link: How to enable/disable toolbar scrolling programmatically when using design support library
In order to hide the Toolbar your can just do something like this:
toolbar.animate().translationY(-toolbar.getBottom()).setInterpolator(new AccelerateInterpolator()).start();
If you want to show it again you call:
toolbar.animate().translationY(0).setInterpolator(new DecelerateInterpolator()).start();

My problem was very similar to #Artem I tried many fix but none of them worked for me. #Jraco11's answer is correct when you use AppBarLayout. #johnrao07 not worked for me. But I found a perfect solution for this problem when we use Toolbar.
To hide Toolbar programatically
if (toolbar.getParent() instanceof AppBarLayout){
((AppBarLayout)toolbar.getParent()).setExpanded(false,true);
}
To show Toolbar programatically
if (toolbar.getParent() instanceof AppBarLayout){
((AppBarLayout)toolbar.getParent()).setExpanded(true,true);
Refer original answer(answer by #Android HHT):- programmatically-show-toolbar-after-hidden-by-scrolling-android-design-library

Configure CoordinatorLayout from code

I'm dynamically injecting a content view into the CoordinatorLayout and would now like to apply a layout_below property to the injected view so that it isn't hidden behind the AppBar.
Is there any way to do this at runtime from code instead of xml properties of the annotation?

Taking one step back and building the entire view in plain xml, I realized that layout_below is not the property I needed for my use case: placing the content view below the app bar. I did not make this clear in my question though, as I assumed layout_below would be the proper option for that.
In fact, to insert a non scrolling view into the CoordinatorLayout it should first be wrapped with a android.support.v4.widget.NestedScrollView. Then, to avoid its content being hidden behind the app bar, it is necessary to update its behavior to android.support.design.widget.AppBarLayout.ScrollingViewBehavior. Otherwise a default behavior is used which will hide behind the app bar.
val viewToInsert = getLayoutInflater.inflate( id, coordinatorWrapper, false )
val p = viewToInsert.getLayoutParams.asInstanceOf[Coordinator.LayoutParams]
p.setBehavior( new ScrollingViewBehavior )
coordinatorWrapper.addView( viewToInsert, 1, p )

You could try setting an anchor.
ContentView view = getContentView(); //your view
CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) view.getLayoutParams();
params.setAnchorId(R.id.app_bar_layout);
params.anchorGravity = Gravity.BOTTOM; //we will anchor to the bottom line of the appbar
params.gravity = Gravity.BOTTOM; //we want to be BELOW that line
view.setLayoutParams(params);

Android: CollapsingToolbarLayout and SearchView, text overlapping

I have little problem with overlapping CollapsingToolbarLayout title with SearchView text. When is CollapsingToolbarLayout expanded, there is no problem:
But when is collapsed, the text is overlapped:
How to fix it?

I tried the answer by Tomas, but it had a problem that as soon as the user scrolls, the appbar collapses again and the problem re-appears.
So I came up with another solution which is to make the collapsed title text transparent when the searchview is expanded. This works nicely and does not depend on or change the collapse/expand state of the appbar.
Simply this:
if (searchViewExpanding) {
collapsingToolbarLayout.setCollapsedTitleTextColor(Color.TRANSPARENT);
} else {
collapsingToolbarLayout.setCollapsedTitleTextColor(Color.WHITE);
}
Of course, you'll need to handle setOnActionExpandListener of your search menu item to know when to call this.

The answer is now simple, expand CollapsingToolbarLayout when search button is clicked. Thanks to Tuấn Trần Anh and this code:
coordinatorLayout = (CoordinatorLayout) findViewById(R.id.coordinator_layout);
appBarLayout = (AppBarLayout) findViewById(R.id.appbar);
CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
AppBarLayout.Behavior behavior = (AppBarLayout.Behavior) params.getBehavior();
behavior.setTopAndBottomOffset(0);
behavior.onNestedPreScroll(coordinatorLayout, appBarLayout, null, 0, 1, new int[2]);
more information is in this thread.

EDIT
Still not solve it, they have soleved another realted problem. With changing the text. The trick now is using the ControllableAppLayout to know when the bar is collapsed or expanded so then you just set and empty title setTitle("")
You can find my implementation here https://gist.github.com/skimarxall/863585dcd7abde8f4153
Issue:
https://code.google.com/p/android/issues/detail?id=178138