How to Hide ActionBar/Toolbar While Scrolling Down in Webview

问题

In Google chrome and play store. the app can hide the actionbar while scrolling and allows the user to Browse conveniently. Please Help me to do like this.

I've used onTouchListener for webview it doesn't works.

mWebView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        getSupportActionBar().show();
                            break;
                    case MotionEvent.ACTION_UP:
                        getSupportActionBar().hide();
                            break;
                    default: break;
                }
                return false;
            }
        });

Thanks in Advance

回答1:

You can do this without any Java code using the design library's CoordinatorLayout and NestedScrollView, with app:layout_scrollFlags set on Toolbar. Here's how you do it.

<android.support.design.widget.CoordinatorLayout 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.support.design.widget.AppBarLayout
    android:id="@+id/appbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:layout_scrollFlags="scroll|enterAlways"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
</android.support.design.widget.AppBarLayout>

<android.support.v4.widget.NestedScrollView 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:layout_gravity="fill_vertical"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <WebView
        android:id="@+id/webview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</android.support.v4.widget.NestedScrollView>
</android.support.design.widget.CoordinatorLayout>

You can play around with with different layout_scrollFlags and fitsSystemWindows behaviour once you get the hang of it.

回答2:

Well I have implemented by CustomWebView and GestureDetector:

CustomWebView.java:

public class CustomWebView extends WebView {
    private GestureDetector gestureDetector;
    public CustomWebView(Context context) {
        super(context);
    }
    public CustomWebView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    public CustomWebView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    @Override
    protected void onScrollChanged(int l, int t, int oldl, int oldt) {
        super.onScrollChanged(l, t, oldl, oldt);
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        return gestureDetector.onTouchEvent(ev) || super.onTouchEvent(ev);
    }

    public void setGestureDetector(GestureDetector gestureDetector) {
        this.gestureDetector = gestureDetector;
    }
}

web_fragment.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:background="@android:color/transparent"
    android:orientation="vertical">

   <com.customview.CustomWebView
            android:id="@+id/customWebView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:focusable="true" />

</LinearLayout>

CustomeGestureDetector clss for Gesture Detection (I have added in Fragment):

private class CustomeGestureDetector extends GestureDetector.SimpleOnGestureListener {
        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            if(e1 == null || e2 == null) return false;
            if(e1.getPointerCount() > 1 || e2.getPointerCount() > 1) return false;
            else {
                try {
                    if(e1.getY() - e2.getY() > 20 ) {
                            // Hide Actionbar
                        getSupportActionBar().hide();
                        customWebView.invalidate();
                       return false;
                    }
                    else if (e2.getY() - e1.getY() > 20 ) {
                            // Show Actionbar
                        getSupportActionBar().show();
                        customWebView.invalidate();
                       return false;
                    }

                } catch (Exception e) {
                    customWebView.invalidate();
                }
                return false;
            }


        }
    }

WebFragment.java:

private CustomWebView customWebView;

customWebView= (CustomWebView) view.findViewById(R.id.customWebView);

customWebView.setGestureDetector(new GestureDetector(new CustomeGestureDetector()));

It works fine for me, hope it would help you.

回答3:

package com.keshav.hideactionbarandfooterexample;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.DecelerateInterpolator;
import android.widget.FrameLayout;
import android.widget.ImageButton;

import java.util.ArrayList;
import java.util.List;

import adapters.RecyclerAdapter;
import listners.HidingScrollListener;

public class MainActivity extends AppCompatActivity {

    private Toolbar mToolbar;
    private Toolbar toolbar_bottom;
    private ImageButton mFabButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        setTheme(R.style.AppThemeRed);
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Log.e("keshav", "MainActivity called");

        initToolbar();
        mFabButton = (ImageButton) findViewById(R.id.fabButton);
        initRecyclerView();
    }

    private void initToolbar() {
        mToolbar = (Toolbar) findViewById(R.id.toolbar);
        toolbar_bottom = (Toolbar) findViewById(R.id.toolbar_bottom);
        setSupportActionBar(mToolbar);
        setSupportActionBar(toolbar_bottom);
        setTitle(getString(R.string.app_name));
        mToolbar.setTitleTextColor(getResources().getColor(android.R.color.white));
        toolbar_bottom.setTitleTextColor(getResources().getColor(android.R.color.white));


        toolbar_bottom.setVisibility(View.GONE);
    }

    private void initRecyclerView() {
        RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        RecyclerAdapter recyclerAdapter = new RecyclerAdapter(createItemList());
        recyclerView.setAdapter(recyclerAdapter);

        recyclerView.addOnScrollListener(new HidingScrollListener() {
            @Override
            public void onHide() {
                hideViews();
            }

            @Override
            public void onShow() {
                showViews();
            }
        });
    }

    private void hideViews() {
        // TODO (-mToolbar)  plus means  2 view above ho jaye or not visible to user
        mToolbar.animate().translationY(-mToolbar.getHeight()).setInterpolator(new AccelerateInterpolator(2));

        // TODO uncomment this Hide Footer in android when Scrolling
        // TODO (+mToolbar)  plus means  2 view forward ho jaye or not visible to user
        toolbar_bottom.animate().translationY(+toolbar_bottom.getHeight()).setInterpolator(new AccelerateInterpolator(2));

        // TODO keshav Hide Also Floatng Button In Android
        FrameLayout.LayoutParams lp = (FrameLayout.LayoutParams) mFabButton.getLayoutParams();
        int fabBottomMargin = lp.bottomMargin;
        mFabButton.animate().translationY(mFabButton.getHeight() + fabBottomMargin).setInterpolator(new AccelerateInterpolator(2)).start();
        // TODO keshav Hide Also Floatng Button In Android
    }

    private void showViews() {
        mToolbar.animate().translationY(0).setInterpolator(new DecelerateInterpolator(2));

        // TODO uncomment this Hide Footer in android when Scrolling
        toolbar_bottom.animate().translationY(0).setInterpolator(new DecelerateInterpolator(2));
        mFabButton.animate().translationY(0).setInterpolator(new DecelerateInterpolator(2)).start();
    }

    private List<String> createItemList() {
        List<String> itemList = new ArrayList<>();
        for (int i = 0; i < 20; i++) {
            itemList.add("Item " + i);
        }
        return itemList;
    }
}

=============================================
             RecyclerAdapter
=============================================
package adapters;

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.keshav.hideactionbarandfooterexample.R;

import java.util.List;

/*
* RecyclerView Adapter that allows to add a header view.
* */
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    private static final int TYPE_HEADER = 2;
    private static final int TYPE_ITEM = 1;
    private List<String> mItemList;

    public RecyclerAdapter(List<String> itemList) {
        mItemList = itemList;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        Context context = parent.getContext();
        if (viewType == TYPE_ITEM) {
            final View view = LayoutInflater.from(context).inflate(R.layout.recycler_item, parent, false);
            return RecyclerItemViewHolder.newInstance(view);
        } else if (viewType == TYPE_HEADER) {
            final View view = LayoutInflater.from(context).inflate(R.layout.recycler_header, parent, false);
            return new RecyclerHeaderViewHolder(view);
        }
        throw new RuntimeException("There is no type that matches the type " + viewType + " + make sure your using types correctly");
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int position) {
        if (!isPositionHeader(position)) {
            RecyclerItemViewHolder holder = (RecyclerItemViewHolder) viewHolder;
            String itemText = mItemList.get(position - 1); // header
            holder.setItemText(itemText);
        }
    }

    public int getBasicItemCount() {
        return mItemList == null ? 0 : mItemList.size();
    }


    @Override
    public int getItemViewType(int position) {
        if (isPositionHeader(position)) {
            return TYPE_HEADER;
        }

        return TYPE_ITEM;
    }

    @Override
    public int getItemCount() {
        return getBasicItemCount() + 1; // header
    }

    private boolean isPositionHeader(int position) {
        return position == 0;
    }

}

=====================================================
         RecyclerHeaderViewHolder
=====================================================
package adapters;

import android.support.v7.widget.RecyclerView;
import android.view.View;

public class RecyclerHeaderViewHolder extends RecyclerView.ViewHolder {
    public RecyclerHeaderViewHolder(View itemView) {
        super(itemView);
    }
}

=====================================================
              RecyclerItemViewHolder
=====================================================

package adapters;

import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.TextView;

import com.keshav.hideactionbarandfooterexample.R;


public class RecyclerItemViewHolder extends RecyclerView.ViewHolder {

    private final TextView mItemTextView;

    public RecyclerItemViewHolder(final View parent, TextView itemTextView) {
        super(parent);
        mItemTextView = itemTextView;
    }

    public static RecyclerItemViewHolder newInstance(View parent) {
        TextView itemTextView = (TextView) parent.findViewById(R.id.itemTextView);
        return new RecyclerItemViewHolder(parent, itemTextView);
    }

    public void setItemText(CharSequence text) {
        mItemTextView.setText(text);
    }

}

===================================================
            activity_main.xml
===================================================

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
                android:layout_width="match_parent"
                android:layout_height="match_parent">

    <android.support.v7.widget.RecyclerView
            android:id="@+id/recyclerView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>

    <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"/>

    <ImageButton
            android:id="@+id/fabButton"
            android:layout_width="56dp"
            android:layout_height="56dp"
            android:layout_gravity="bottom|right"
            android:layout_marginBottom="16dp"
            android:layout_marginRight="16dp"
            android:background="@drawable/fab_bcg"
            android:src="@drawable/ic_favorite_outline_white_24dp"
            android:contentDescription="@string/fab_description"/>


    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar_bottom"
        android:layout_width="match_parent"
        android:layout_alignParentBottom="true"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"/>

    </RelativeLayout>

</FrameLayout>


==================================================
    recycle_header.xml in layout folder
==================================================

<?xml version="1.0" encoding="utf-8"?>
<View xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="?attr/actionBarSize"/>

==================================================
    recycle_item.xml in layout folder
==================================================
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:layout_margin="8dp"
    card_view:cardCornerRadius="4dp">
    <TextView
        android:id="@+id/itemTextView"
        android:layout_width="match_parent"
        android:layout_height="?attr/listPreferredItemHeight"
        android:gravity="center_vertical"
        android:padding="8dp"
        style="@style/Base.TextAppearance.AppCompat.Body2"/>
</android.support.v7.widget.CardView>


=================================================
                      styles.xml
=================================================
<resources>

    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
    </style>

    <style name="AppThemeRed" parent="AppTheme">
        <item name="colorPrimary">@color/color_primary_red</item>
        <item name="colorPrimaryDark">@color/color_primary_red_dark</item>
    </style>

    <style name="AppThemeGreen" parent="AppTheme">
        <item name="colorPrimary">@color/color_primary_green</item>
        <item name="colorPrimaryDark">@color/color_primary_green_dark</item>
    </style>

    <style name="AppThemeBlue" parent="AppTheme">
        <item name="colorPrimary">@color/color_primary_blue</item>
        <item name="colorPrimaryDark">@color/color_primary_blue_dark</item>
        <item name="colorAccent">@color/color_accent_pink</item>
    </style>

</resources>

build.gradle Dependency

  compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support:recyclerview-v7:25.3.1'
    compile 'com.android.support:cardview-v7:25.3.1'
    compile 'com.android.support:design:25.3.1'

来源：https://stackoverflow.com/questions/28770530/how-to-hide-actionbar-toolbar-while-scrolling-down-in-webview