Hiding ‘Bottom Navigation Bar’ whilst keyboard is present – Android



I have a small demo chat UI application. This application has a bottom navigation bar. I need the bottom navigation bar to hide when the keyboard appears.

Here is an example of the chat UI

As you can see when you click in the EditText element, the keyboard appears but the bottom navigation bar stays visible. I have tried methods such as this measurement method, but the UI elements flicker like this.

Is there a proper way to hide the bottom navigation bar when the keyboard is visible?

EDIT: In the below activity you can see where I set the keyboard listener to adjust the position of UI elements when the keyboard is determined as being visible.

This is my activity code, uses setKeyboardListener method from the above link and set it in onCreateView:

package uk.cal.codename.projectnedry.TeamChatFragment;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.graphics.Rect;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.text.Layout;
import android.util.DisplayMetrics;
import android.util.Log;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.view.Window;
import android.view.WindowManager;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.FrameLayout;
import android.widget.ImageButton;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.Toast;

import com.roughike.bottombar.BottomBar;

import java.util.ArrayList;

import butterknife.BindView;
import butterknife.ButterKnife;
import uk.cal.codename.projectnedry.R;
import uk.cal.codename.projectnedry.TeamChatFragment.ListAdapter.TeamChatListAdapter;
import uk.demo.cal.genericmodelviewpresenter.GenericMvp.GenericMvpFragment;

import static android.view.View.GONE;

/**
 * A simple {@link Fragment} subclass.
 * Activities that contain this fragment must implement the
 * {@link TeamChatView.OnFragmentInteractionListener} interface
 * to handle interaction events.
 * Use the {@link TeamChatView#newInstance} factory method to
 * create an instance of this fragment.
 */
public class TeamChatView extends GenericMvpFragment implements TeamChatContract.RequiredViewOps {

    private OnFragmentInteractionListener mListener;
    @BindView(R.id.teamChatList)
    RecyclerView mTeamChatRecyclerView;
    @BindView(R.id.teamChatSendButton)
    ImageButton mTeamChatSendButton;
    @BindView(R.id.messageTextInput)
    EditText mMessageTextInput;
    TeamChatListAdapter mTeamChatListAdapter;
    TeamChatListAdapter.ClickListener mTeamChatListClickListener;
    private ArrayList<String> mTestMessageList;

    public interface OnKeyboardVisibilityListener {
        void onVisibilityChanged(boolean visible);
    }

    public final void setKeyboardListener(final OnKeyboardVisibilityListener listener) {
        final View activityRootView = ((ViewGroup) getActivity().findViewById(android.R.id.content)).getChildAt(0);

        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

            private boolean wasOpened;

            private final int DefaultKeyboardDP = 100;

            // From @nathanielwolf answer...  Lollipop includes button bar in the root. Add height of button bar (48dp) to maxDiff
            private final int EstimatedKeyboardDP = DefaultKeyboardDP + (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ? 48 : 0);

            private final Rect r = new Rect();

            @Override
            public void onGlobalLayout() {
                // Convert the dp to pixels.
                int estimatedKeyboardHeight = (int) TypedValue
                        .applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP, activityRootView.getResources().getDisplayMetrics());

                // Conclude whether the keyboard is shown or not.
                activityRootView.getWindowVisibleDisplayFrame(r);
                int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
                boolean isShown = heightDiff >= estimatedKeyboardHeight;

                if (isShown == wasOpened) {
                    Log.d("Keyboard state", "Ignoring global layout change...");
                    return;
                }

                wasOpened = isShown;
                listener.onVisibilityChanged(isShown);
            }
        });
    }

    public TeamChatView() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @return A new instance of fragment TeamChatView.
     */
    public static TeamChatView newInstance() {
        TeamChatView fragment = new TeamChatView();
        Bundle args = new Bundle();
        fragment.setArguments(args);
        return fragment;
    }

    @SuppressLint("MissingSuperCall")
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(TeamChatPresenter.class, TeamChatModel.class, savedInstanceState);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        final View view = inflater.inflate(R.layout.fragment_team_chat_view, container, false);
        this.mUnbinder = ButterKnife.bind(this, view);

        mTestMessageList = new ArrayList<>();
        this.mTeamChatListAdapter = new TeamChatListAdapter(mTestMessageList);
        this.mTeamChatRecyclerView.setAdapter(this.mTeamChatListAdapter);
        final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getContext());
        this.mTeamChatRecyclerView.setLayoutManager(linearLayoutManager);

        this.mTeamChatSendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if(!String.valueOf(mMessageTextInput.getText()).equals("")) {
                    getSpecificImpOfGenericPresenter().sendMessage(String.valueOf(mMessageTextInput.getText()));
                    mMessageTextInput.setText("");
                    mTeamChatRecyclerView.smoothScrollToPosition(mTestMessageList.size());
                }
            }
        });

        setKeyboardListener(new OnKeyboardVisibilityListener(){
            @Override
            public void onVisibilityChanged(boolean visible) {
                RelativeLayout contentFrame = (RelativeLayout) getActivity().findViewById(R.id.content_company_navigation);
                BottomBar lowerNavigationBar = (BottomBar) getActivity().findViewById(R.id.bottomBar);
                if (visible) { // if more than 100 pixels, its probably a keyboard...
                    lowerNavigationBar.setVisibility(GONE);
                    contentFrame.setPadding(0, 0, 0, 0);
                    mTeamChatRecyclerView.smoothScrollToPosition(mTestMessageList.size());
                } else {
                    contentFrame.setPadding(0, 0, 0, convertDpToPixel(60, getContext()));
                    mTeamChatRecyclerView.smoothScrollToPosition(mTestMessageList.size());
                    lowerNavigationBar.setVisibility(View.VISIBLE);
                }
            }
        });
        return view;
    }

    /**
     * This method converts dp unit to equivalent pixels, depending on device density.
     *
     * @param dp A value in dp (density independent pixels) unit. Which we need to convert into pixels
     * @param context Context to get resources and device specific display metrics
     * @return A float value to represent px equivalent to dp depending on device density
     */
    public static int convertDpToPixel(float dp, Context context){
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        int px = (int) (dp * ((float)metrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT));
        return px;
    }

    public void addToTestMessageList(String str){
        this.mTestMessageList.add(str);
        this.mTeamChatListAdapter.notifyDataSetChanged();
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
       // getView().getViewTreeObserver().removeGlobalOnLayoutListener(test);
    }

    @Override
    public TeamChatPresenter getSpecificImpOfGenericPresenter() {
        return (TeamChatPresenter) this.mPresenter;
    }
}

This is my XML layout:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="uk.cal.codename.projectnedry.TeamChatFragment.TeamChatView">

    <android.support.v7.widget.RecyclerView
        android:layout_above="@+id/chatViewMessageEntryLayout"
        android:id="@+id/teamChatList"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:isScrollContainer="false"
        android:paddingTop="10dp"
        android:scrollbars="vertical" />    

    <RelativeLayout
        android:id="@+id/chatViewMessageEntryLayout"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:layout_alignParentBottom="true"
        android:orientation="horizontal">

        <View
            android:id="@+id/chatViewMessageEntrySeperator"
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="#e3e3e8" />

        <EditText
            android:id="@+id/messageTextInput"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_gravity="center_vertical"
            android:layout_below="@+id/chatViewMessageEntrySeperator"
            android:layout_toLeftOf="@+id/teamChatSendButton"
            android:background="@android:color/transparent"
            android:hint="Enter message"
            android:inputType="textCapSentences|textMultiLine"
            android:maxLength="1000"
            android:maxLines="4"
            android:paddingLeft="10dp" />

        <ImageButton
            android:id="@+id/teamChatSendButton"
            android:layout_width="50dp"
            android:layout_height="match_parent"
            android:layout_alignParentRight="true"
            android:layout_gravity="center"
            android:background="#00B9EF"
            android:src="@drawable/ic_send_white_24dp" />

    </RelativeLayout>

</RelativeLayout>

Answer

I ended up using the height measuring method that seems to be the standard way of soft keyboard detection which is described in this answer. However, I used this library’s implementation of it, as it is still the same ViewTreeObserver.OnGlobalLayoutListener method, implemented well, and allowed me to abstract the code out of my applications main codebase.

When this keyboard visibility listener is triggered, I then hide/show the bottom navigation bar (which I have explained here).



Source: stackoverflow