Show CollapsingToolbarLayout Title ONLY when collapsed

问题

the title says it all. I've tried setExpandedTitleColor and setCollapsedTitleColor (switching to and from transparent) with no luck. I can't see any built in methods that'll do what I'm looking for, either.

I only want to show the title when the CollapsingToolbarLayout is fully collapsed, otherwise, I need it hidden.

Any hints?

回答1:

You can add OnOffsetChangedListener to AppBarLayout to determine when CollapsingToolbarLayout is collapsed or expanded and set it's title.

final CollapsingToolbarLayout collapsingToolbarLayout = (CollapsingToolbarLayout) findViewById(R.id.collapsingToolbarLayout);
AppBarLayout appBarLayout = (AppBarLayout) findViewById(R.id.appBarLayout);
appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
    boolean isShow = true;
    int scrollRange = -1;

    @Override
    public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
        if (scrollRange == -1) {
            scrollRange = appBarLayout.getTotalScrollRange();
        }
        if (scrollRange + verticalOffset == 0) {
            collapsingToolbarLayout.setTitle("Title");
            isShow = true;
        } else if(isShow) {
            collapsingToolbarLayout.setTitle(" ");//careful there should a space between double quote otherwise it wont work 
            isShow = false;
        }
    }
});

回答2:

I tried dlohani's solution, but didn't like it because of the fading out. With this solution, you remove the fading completely.

The trick is to create a new style with textSize equal to 0.1sp or 0sp (this one crashes on SDK < 19) and textColor transparent:

For SDK < 19

<style name="CollapsingToolbarLayoutExpandedTextStyle" parent="AppTheme">
    <item name="android:textColor">@android:color/transparent</item>
    <item name="android:textSize">0.1sp</item>
</style>

For SDK >= 19

<style name="CollapsingToolbarLayoutExpandedTextStyle" parent="AppTheme">
    <item name="android:textColor">@android:color/transparent</item>
    <item name="android:textSize">0sp</item>
</style>

Then apply it to the CollapsingToolbarLayout in your layout:

    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:expandedTitleTextAppearance="@style/CollapsingToolbarLayoutExpandedTextStyle"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">

回答3:

I was able to get the desired effect by adding following property to the xml layout:

app:expandedTitleTextAppearance="@android:color/transparent"

so my CollapsingToolbarLayout looks like this

<android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsingToolbarLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:expandedTitleTextAppearance="@android:color/transparent"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">

回答4:

I have a more simple answer:

final CollapsingToolbarLayout collapsingToolbarLayout = (CollapsingToolbarLayout) findViewById(R.id.toolbar_layout);

collapsingToolbarLayout.setTitle("Your Title");
collapsingToolbarLayout.setExpandedTitleColor(getResources().getColor(R.color.transperent)); // transperent color = #00000000
collapsingToolbarLayout.setCollapsedTitleTextColor(Color.rgb(0, 0, 0)); //Color of your title

Happy Coding!

回答5:

This code works for me: Use color.parse color because if your background color is different then replace with white and your title not display

collapsingToolbarLayout.setExpandedTitleColor(Color.parseColor("#00FFFFFF"));

Or you can use for transparent collapsingToolbarLayout.setExpandedTitleColor(Color.TRANSPARENT);

回答6:

I successfully add a fading textview, it was so simple. I can't believe no one came up with this. Add a text view in toolbar, and set it's alpha based on the verticalOffset in appbar callback

mAppBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {

        @Override
        public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {

            mTitleTextView.setAlpha(Math.abs(verticalOffset / (float)
                    appBarLayout.getTotalScrollRange()));
        }
    });

回答7:

Here the simplest and working solution also with api 23:

app:expandedTitleTextAppearance has to inherit TextAppearance.

So, in your styles.xml add this rows:

<style name="TransparentText" parent="@android:style/TextAppearance">
   <item name="android:textColor">#00000000</item>
</style>

Then, in your CollapsingToolbarLayout, add this row.

app:expandedTitleTextAppearance="@style/TransparentText"

That's all folks!

回答8:

Here is my solution:

collapsingToolbar.setCollapsedTitleTextAppearance(R.style.personal_collapsed_title);
collapsingToolbar.setExpandedTitleTextAppearance(R.style.personal_expanded_title);

<style name="personal_collapsed_title">
     <item name="android:textSize">18sp</item>
     <item name="android:textColor">@color/black</item>
</style>

<style name="personal_expanded_title">
     <item name="android:textSize">0sp</item>
</style>

回答9:

The below solution works perfectly.

appbar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
                @Override
                public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
                    if (Math.abs(verticalOffset)-appBarLayout.getTotalScrollRange() == 0)
                    {
                        // Collapsed
                        setTitle("Title To Show");
                    }
                    else
                    {
                        // Expanded
                        setTitle("");
                    }
                }
            });

回答10:

In my oppinion a bit more elegant solution would be something like this.

public class MyCollapsingToolbarLayout extends CollapsingToolbarLayout {

    private final int toolbarId;
    @Nullable private Toolbar toolbar;

    public MyCollapsingToolbarLayout(Context context, AttributeSet attrs) {
        super(context, attrs);

        setTitleEnabled(false);

        TypedArray a = context.obtainStyledAttributes(attrs,
                R.styleable.CollapsingToolbarLayout, 0,
                R.style.Widget_Design_CollapsingToolbar);

        toolbarId = a.getResourceId(android.support.design.R.styleable.CollapsingToolbarLayout_toolbarId, -1);

        a.recycle();

    }

    @Override public void setScrimsShown(boolean shown, boolean animate) {
        super.setScrimsShown(shown, animate);

        findToolbar();
        if (toolbar != null) {
            toolbar.setTitleTextColor(shown ? Color.WHITE : Color.TRANSPARENT);
        }
    }

    private void findToolbar() {
        if (toolbar == null) {
            toolbar = (Toolbar) findViewById(toolbarId);
        }
    }

}

And usage would look something like this

<butter.droid.widget.BurtterCollapsingToolbarLayout
        app:toolbarId="@+id/toolbar"
        ...>

There is also a possibility to fade out/in text instead of just showing or hiding it.

回答11:

This works for me.

final Toolbar tool = (Toolbar)findViewById(R.id.toolbar);
CollapsingToolbarLayout c = (CollapsingToolbarLayout)findViewById(R.id.collapsing_toolbar);
AppBarLayout appbar = (AppBarLayout)findViewById(R.id.app_bar_layout);
tool.setTitle("");
setSupportActionBar(tool);
c.setTitleEnabled(false);

appbar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
    boolean isVisible = true;
    int scrollRange = -1;
    @Override
    public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
        if (scrollRange == -1) {
            scrollRange = appBarLayout.getTotalScrollRange();
        }
        if (scrollRange + verticalOffset == 0) {
           tool.setTitle("Title");
            isVisible = true;
        } else if(isVisible) {
            tool.setTitle("");
            isVisible = false;
        }
    }
});

来源：https://stackoverflow.com/questions/31662416/show-collapsingtoolbarlayout-title-only-when-collapsed