Faster activity transition

Question

I have created a basic Activity with a WebView. I have added a method in the WebView which loads an error.html page from the asset folder when the WebView receives a HTTP error. I wanted to hide the Share menu item when this error.html page was loaded and so, I moved this to a new Activity.

Now, what's happening is, when there's a connectivity error, the default connectivity error of Android loads first and then the Activity transition takes place. Thus, even though the transition is working fine, users can see the deault Android connectivity error page for a few milliseconds. Is there any way in which I can hide that error page completely as such the users can only see my custom error page.

Here's my MainActivity.java:

package com.ananya.brokenhearts;

import android.annotation.SuppressLint;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.webkit.WebChromeClient;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.Toast;

@SuppressWarnings("deprecation")

public class MainActivity extends AppCompatActivity
{
    private WebView WebView;
    private ProgressBar ProgressBar;
    private LinearLayout LinearLayout;
    private String currentURL;

    @SuppressLint("SetJavaScriptEnabled")

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

        WebView = findViewById(R.id.webView);
        ProgressBar = findViewById(R.id.progressBar);
        LinearLayout = findViewById(R.id.layout);

        ProgressBar.setMax(100);

        WebView.loadUrl("https://www.brokenhearts.ml/index.html");
        WebView.getSettings().setJavaScriptEnabled(true);
        WebView.getSettings().setUserAgentString("Broken Hearts/1.0");
        WebView.setWebViewClient(new WebViewClient()
        {
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon)
            {
                LinearLayout.setVisibility(View.VISIBLE);
                super.onPageStarted(view, url, favicon);
            }

            @Override
            public void onPageFinished(WebView view, String url)
            {
                LinearLayout.setVisibility(View.GONE);
                super.onPageFinished(view, url);
                currentURL = url;
            }

            @Override
            public void onReceivedError(WebView webview, int i, String s, String s1)
            {
                Intent intent = new Intent(MainActivity.this, ErrorActivity.class);
                startActivity(intent);
                finish();
            }

            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url2)
            {
                if (url2.contains("www.brokenhearts.ml"))
                {
                    view.loadUrl(url2);
                    return false;
                } else
                {
                    Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url2));
                    startActivity(intent);
                    return true;
                }
            }

        });

        WebView.setWebChromeClient(new WebChromeClient()
        {
            @Override
            public void onProgressChanged(WebView view, int newProgress)
            {
                super.onProgressChanged(view, newProgress);
                ProgressBar.setProgress(newProgress);
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu)
    {
        MenuInflater menuInflater = getMenuInflater();
        menuInflater.inflate(R.menu.menu, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
        switch (item.getItemId())
        {
            case R.id.backward:
                onBackPressed();
                break;

            case R.id.forward:
                onForwardPressed();
                break;

            case R.id.refresh:
                WebView.reload();
                break;

            case R.id.share:
                Intent shareIntent = new Intent(Intent.ACTION_SEND);
                shareIntent.setType("text/plain");
                shareIntent.putExtra(Intent.EXTRA_TEXT,currentURL);
                shareIntent.putExtra(Intent.EXTRA_SUBJECT,"Copied URL");
                startActivity(Intent.createChooser(shareIntent,"Share URL"));
                break;

            case R.id.update:
                Intent intent = new Intent(MainActivity.this, UpdateActivity.class);
                startActivity(intent);
                finish();
                break;

            case R.id.exit:
                new AlertDialog.Builder(this,R.style.AlertDialog)
                        .setIcon(R.drawable.ic_error_black_24dp)
                        .setTitle("Are you sure you want to exit?")
                        .setMessage("Tapping 'Yes' will close the app. Tap 'No' to continue using the app")
                        .setPositiveButton("Yes",
                                new DialogInterface.OnClickListener()
                                {
                                    @Override
                                    public void onClick(DialogInterface dialog, int which)
                                    {
                                        finish();
                                    }
                                })
                        .setNegativeButton("No", null)
                        .show();
                break;
        }
        return super.onOptionsItemSelected(item);
    }

    private void onForwardPressed()
    {
        if (WebView.canGoForward())
        {
            WebView.goForward();
        } else
        {
            Toast.makeText(this, "Can't go further", Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public void onBackPressed ()
    {
        if (WebView.canGoBack())
        {
            WebView.goBack();
        } else
        {
            new AlertDialog.Builder(this,R.style.AlertDialog)
                    .setIcon(R.drawable.ic_error_black_24dp)
                    .setTitle("Are you sure you want to exit?")
                    .setMessage("Tapping 'Yes' will close the app. Tap 'No' to continue using the app")
                    .setPositiveButton("Yes",
                            new DialogInterface.OnClickListener()
                            {
                                @Override
                                public void onClick(DialogInterface dialog, int which)
                                {
                                    finish();
                                }
                            })
                    .setNegativeButton("No", null)
                    .show();
        }
    }
}

Prior to this, I was directly loading the error.html page in the MainActivity itself when there was an error and thus, the default error page wasn't visible. But, I wanted to hide the Share button when error.html page was loaded. I didn't know how to do and I didn't get any response to that question where I had posted it. Thus, I thought of creating a seperate Activity to load the error.html which can let me hide the Share menu icon.

Also, I've tried to add the WebView.loadUrl("file:///android_asset/error.html"); in the same method before that intent hoping that it'll load before the Activity transition, however, that didn't help. I can still see the default Android connectivity error page.

Just to clarify, this is the default error page that I'm talking about: https://i.sstatic.net/bMMHh.png and there's a custom one that I've made that I'm displaying now in the ErrorActivity.java.

What can I do about this?

Answer 1

Regarding hiding the share menu icon, you could always use onPrepareOptionsMenu() to hide your share menu if there is any error flag.

@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    super.onPrepareOptionsMenu(menu);
    menu.findItem(R.id.share).setVisible(!isPageError);
    return true;
}

which would require you to have a isPageError boolean set to true in your

@Override
public void onReceivedError(WebView webview, int i, String s, String s1{
    isPageError = true;
}

Answer 2

Hide the webview when an error occured.

 @Override
      public void onReceivedError(WebView webview, int i, String s, String s1)
        {
            WebView.setVisibility(View.GONE);**hide the webview when an error occured**
            Intent intent = new Intent(MainActivity.this, ErrorActivity.class);
            startActivity(intent);
            finish();
        }