Need to disable expand on CollapsingToolbarLayout for certain fragments

Question

I have a AppCompatActivity that controls replacing many fragments. Here is my layout for it.

activity_main.xml

Answer 1

Locking and unlocking was not enough, simple lockings keeps the image shrinked; here my solution

Call this on resume that requires toolbar in collapsed mode.

private void lockAppBarClosed() {

    appBarLayout.setExpanded(false,true);
    CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
    ((CustomAppBarLayoutBehavior)layoutParams.getBehavior()).setScrollBehavior(false);

    AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) collapsingToolbarLayout.getLayoutParams();
    params.setScrollFlags(0);
    params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL | AppBarLayout.LayoutParams.SCROLL_FLAG_EXIT_UNTIL_COLLAPSED);

}

This is for a fragment that requires Snap

public void unlockAppBarOpen() {

    appBarLayout.setExpanded(true,true);
    CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
    ((CustomAppBarLayoutBehavior)layoutParams.getBehavior()).setScrollBehavior(true);


    AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) collapsingToolbarLayout.getLayoutParams();
    params.setScrollFlags(0);
    params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL | AppBarLayout.LayoutParams.SCROLL_FLAG_SNAP);

}

This is for a fragment requires scroll with SCROLL_FLAG_EXIT_UNTIL_COLLAPSED mode.

public void unlockAppBarOpen() {

    appBarLayout.setExpanded(true,true);
    CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
    ((CustomAppBarLayoutBehavior)layoutParams.getBehavior()).setScrollBehavior(true);


    AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) collapsingToolbarLayout.getLayoutParams();
    params.setScrollFlags(0);
    params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL | AppBarLayout.LayoutParams.SCROLL_FLAG_EXIT_UNTIL_COLLAPSED);

}

And the CustomAppBarLayoutBehavior.java

public class CustomAppBarLayoutBehavior extends AppBarLayout.Behavior {

    private boolean shouldScroll = false;

    public CustomAppBarLayoutBehavior() {
        super();
    }

    public CustomAppBarLayoutBehavior(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean onStartNestedScroll(CoordinatorLayout parent, AppBarLayout child, View directTargetChild, View target, int nestedScrollAxes, int type) {
        return shouldScroll;
    }

    @Override
    public boolean onTouchEvent(CoordinatorLayout parent, AppBarLayout child, MotionEvent ev) {
        if(shouldScroll){
            return super.onTouchEvent(parent, child, ev);
        }else{
            return false;
        }
    }

    public void setScrollBehavior(boolean shouldScroll){
        this.shouldScroll = shouldScroll;
    }

    public boolean isShouldScroll(){
        return shouldScroll;
    }
}

provide this behavior to AppBarLayout

 <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/app_bar_layout"
        android:layout_width="match_parent"
        android:layout_height="210dp"
        app:layout_behavior=".behaviors.CustomAppBarLayoutBehavior"
        android:theme="@style/ThemeOverlay.MaterialComponents.ActionBar.Primary">

Answer 2

None of the provided solutions worked for me except this one. With this solution, i can easily manage the state of collapsing toolbar. This will prevent expanding of collapsing toolbar and set title for it.

public void lockAppBar(boolean locked,String title) {
    if(locked){
        appBarLayout.setExpanded(false, true);
        int px = (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 80, getResources().getDisplayMetrics());
        CoordinatorLayout.LayoutParams lp = (CoordinatorLayout.LayoutParams)appBarLayout.getLayoutParams();
        lp.height = px;
        appBarLayout.setLayoutParams(lp);
        collapsingToolbarLayout.setTitleEnabled(false);
        toolbar.setTitle(title);
    }else{
        appBarLayout.setExpanded(true, false);
        appBarLayout.setActivated(true);
        CoordinatorLayout.LayoutParams lp = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
        lp.height = (int) getResources().getDimension(R.dimen.toolbarExpandHeight);
        collapsingToolbarLayout.setTitleEnabled(true);
        collapsingToolbarLayout.setTitle(title);
    }
}

Answer 3

Now, in v23 of support library you can easily control your appbar visibility.

Just get a reference to your AppBarLayout and hide/show it depending on the fragment you want to load:

private AppBarLayout appBarLayout;

@Override
protected void onCreate(Bundle savedInstanceState) {
[...]
appBarLayout = (AppBarLayout) findViewById(R.id.appbar);
[...]
}

public void switchToFragment(Fragment fragment, String tag, boolean expandToolbar){
        FragmentManager fragmentManager = getSupportFragmentManager();

        Fragment currentFragment = fragmentManager.findFragmentByTag(currentFragmentTag);

        if(currentFragment == null || !TextUtils.equals(tag, currentFragmentTag) ){
            currentFragmentTag = tag;
            fragmentManager
                    .beginTransaction()
                    .replace(R.id.flContent, fragment, currentFragmentTag)
                    .commit();

            if(expandToolbar){
                appBarLayout.setExpanded(true,true);
            }else{
                appBarLayout.setExpanded(false,true);
            }
        }
    }

P.S. don't forget to add the required dependencies in your build.gradle:

dependencies {  
    compile 'com.android.support:design:23.2.1'
    compile 'com.android.support:appcompat-v7:23.2.1'
    compile 'com.android.support:recyclerview-v7:23.2.1' 
}

EDIT: If you also want to lock your toolbar in certain fragments (apart from collapsing) you have to resort to workarounds as this feature is not provided by CollapsingToolbarLayout until now (v23.2.1 of support design). Here you can find my proposed workaround.

Answer 4

The following code achieves 3 objectives:

Disable CollapsingToolbarLayout expand or collapse by the user, but still allow AppBarLayout.setExpanded.

Prevent scrolling of RecyclerView or NestedScrollView from expanding or collapsing the CollapsingToolbarLayout.

// scrollView can be RecyclerView or NestedScrollView
ViewCompat.setNestedScrollingEnabled(scrollView, false)

Prevent the user from expanding or collapsing the CollapsingToolbarLayout by flicking the AppBar.

val params = appBar.layoutParams as CoordinatorLayout.LayoutParams
if (params.behavior == null)
    params.behavior = AppBarLayout.Behavior()
val behaviour = params.behavior as AppBarLayout.Behavior
behaviour.setDragCallback(object : AppBarLayout.Behavior.DragCallback() {
    override fun canDrag(appBarLayout: AppBarLayout): Boolean {
        return false
    }
})

https://code.luasoftware.com/tutorials/android/how-to-disable-or-lock-collapsingtoolbarlayout-collapse-or-expand/

Answer 5

I can't comment, so I will post my additions to JasonWyatt's DisableableAppBarLayoutBehavior solution as independent answer.

public class DisableableAppBarLayoutBehavior extends AppBarLayout.Behavior {
    private boolean mEnabled = true; // enabled by default

    public DisableableAppBarLayoutBehavior() {
        super();
    }

    public DisableableAppBarLayoutBehavior(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public void setEnabled(boolean enabled) {
        mEnabled = enabled;
    }

    @Override
    public boolean onStartNestedScroll(CoordinatorLayout parent, AppBarLayout child, View directTargetChild, View target, int nestedScrollAxes, int type) {
        return mEnabled && super.onStartNestedScroll(parent, child, directTargetChild, target, nestedScrollAxes, type);
    }

    @Override
    public void onNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type) {
        if (!isEnabled()) return;
        super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, type);
    }

    @Override
    public void onNestedPreScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, int dx, int dy, int[] consumed, int type) {
        if (!isEnabled()) return;
        super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
    }

    public boolean isEnabled() {
        return mEnabled;
    }
}

In addition to onStartNestedScroll also lock onNestedPreScroll and onNestedScroll itself to avoid unexpected behaviour. For example, in my case - calling setExpanded(false, true) on my app bar was braking expected behaviour and still was expanding with lags. Now it works:

LayoutParams layoutParams = (LayoutParams) context.appBarLayout.getLayoutParams();
((DisableableAppBarLayoutBehavior)layoutParams.getBehavior()).setEnabled(false);
context.appBarLayout.setLayoutParams(layoutParams);
context.appBarLayout.setExpanded(false, true); // collapse app bar

Answer 6

All you have to do is replace CoordinatorLayout with custom implementation of CoordinatorLayout which will cheat that nested scrolling has been handled.

MyCoordinatorLayout implementation:

public class MyCoordinatorLayout extends CoordinatorLayout {

    private boolean allowForScroll = false;

    public MyCoordinatorLayout(Context context) {
        super(context);
    }

    public MyCoordinatorLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) {
        return allowForScroll && super.onStartNestedScroll(child, target, nestedScrollAxes);
    }

    public boolean isAllowForScroll() {
        return allowForScroll;
    }

    public void setAllowForScroll(boolean allowForScroll) {
        this.allowForScroll = allowForScroll;
    }
}

activity view xml:

<LinearLayout
    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:orientation="vertical"
    >

    <android.support.v4.widget.DrawerLayout
        android:id="@+id/drawerLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        >

        <!--CONTENT-->

        <com.example.views.MyCoordinatorLayout
            android:id="@+id/coordinator"
            xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:app="http://schemas.android.com/apk/res-auto"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            >

        <com.example.views.ControllableAppBarLayout
            android:id="@+id/appbar"
            android:layout_width="match_parent"
            android:layout_height="192dp"
            android:fitsSystemWindows="true"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

            <android.support.design.widget.CollapsingToolbarLayout
                android:id="@+id/collapsing_toolbar"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                app:contentScrim="?attr/colorPrimary"
                app:expandedTitleMarginBottom="32dp"
                app:expandedTitleMarginEnd="64dp"
                app:expandedTitleMarginStart="48dp"
                app:layout_scrollFlags="scroll|exitUntilCollapsed">

                <ImageView
                    android:id="@+id/header"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:background="@color/primary"
                    android:fitsSystemWindows="true"
                    android:scaleType="centerCrop"
                    app:layout_collapseMode="parallax" />

                <android.support.v7.widget.Toolbar
                    android:id="@+id/toolbar"
                    android:layout_width="match_parent"
                    android:layout_height="?attr/actionBarSize"
                    app:layout_collapseMode="pin"
                    app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

            </android.support.design.widget.CollapsingToolbarLayout>

        </com.example.views.ControllableAppBarLayout>

        <FrameLayout
            android:id="@+id/flContent"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            />

        </com.example.views.MyCoordinatorLayout>


        <!-- DRAWER -->

        <fragment
            android:id="@+id/fDrawer"
            android:name="com.example.fragment.DrawerFragment"
            android:layout_width="@dimen/drawer_width"
            android:layout_height="match_parent"
            android:layout_gravity="left|start"
            android:fitsSystemWindows="true"
            android:clickable="true"
            />

    </android.support.v4.widget.DrawerLayout>

</LinearLayout>

I encourage you to use custom AppBarLayout implementation with helper methods to collapse/expand toolbar. On this gist you can find one.

Ok, now it's time to configure our toolbar in activity.

public class ToolbarAppcompatActivity extends AppCompatActivity
        implements AppBarLayout.OnOffsetChangedListener {

    protected Toolbar toolbar;
    protected MyCoordinatorLayout coordinator;
    protected ControllableAppBarLayout appbar;

    @Override protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        configureToolbar();
    switchFragment(new FooFragment(), "FOO", true);
    }

    protected void configureToolbar() {
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        coordinator = (MyCoordinatorLayout) findViewById(R.id.coordinator);
        appbar = (ControllableAppBarLayout) findViewById(R.id.appbar);
        appbar.addOnOffsetChangedListener(this);
        getDelegate().setSupportActionBar(toolbar);
    }

    public void switchToFragment(Fragment fragment, String tag, boolean expandToolbar){
        FragmentManager fragmentManager = getSupportFragmentManager();

        Fragment currentFragment = fragmentManager.findFragmentByTag(currentFragmentTag);

        if(currentFragment == null || !TextUtils.equals(tag, currentFragmentTag) ){
            currentFragmentTag = tag;
            fragmentManager
                    .beginTransaction()
                    .replace(R.id.flContent, fragment, currentFragmentTag)
                    .commit();

            if(expandToolbar){
                expandToolbar();
            }else{
                collapseToolbar();
            }
        }
    }

    protected void addFragment(Fragment fragment, String tag, boolean expandToolbar) {
        FragmentManager fragmentManager = getSupportFragmentManager();
        currentFragmentTag = tag;
        fragmentManager
                .beginTransaction()
                .add(R.id.flContent, fragment, currentFragmentTag)
                .addToBackStack(tag)
                .commit();

        if(expandToolbar){
            expandToolbar();
        }else{
            collapseToolbar();
        }
    }

   protected void collapseToolbar(){
        appbar.collapseToolbar();
        coordinator.setAllowForScroll(false);
    }

    public void expandToolbar(){
        appbar.expandToolbar();
        coordinator.setAllowForScroll(true);
    }

}

Every time you want to switch fragment and collapse/expand toolbar just call method switchFragment/addFragment with proper boolean parameter.

Just one last note. Make sure you use latest support libraries.

dependencies {

    // android support
    compile 'com.android.support:appcompat-v7:22.2.1'
    compile 'com.android.support:recyclerview-v7:22.2.1'
    compile 'com.android.support:design:22.2.1'

}

Do not use include tag in AppBarLayout. It does not work