I am creating an application for my robotics team so that we can quickly browse a few important websites. The issue I am having is that I can navigate through one of the fragments using the back button(until it exits from the app), but the other fragment titled "delphiFragment" is not able to navigate backwards through the website.
If there is any other information I can provide, please say so.
Here is my main activity
package com.thirdspare.android.ckcyberpackapp;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v7.app.AppCompatActivity;
import android.view.KeyEvent;
import android.view.MenuItem;
import android.webkit.WebView;
import android.widget.TextView;
import static com.thirdspare.android.ckcyberpackapp.R.id.container;
public class MainActivity extends AppCompatActivity {
Fragment homeFragment = new HomeFragment();
Fragment delphiFragment = new DelphiFragment();
Fragment tbaFragment = new TBAFragment();
private TextView mTextMessage;
public static WebView mWebView;
private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
= new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.navigation_home:
mTextMessage.setText(R.string.title_home);
getFragmentManager().beginTransaction()
.show(homeFragment)
.commit();
return true;
case R.id.navigation_delphi:
// mTextMessage.setText(R.string.title_delphi);
getFragmentManager().beginTransaction()
.show(delphiFragment)
.hide(homeFragment)
.hide(tbaFragment)
.commit();
return true;
case R.id.navigation_TBA:
mTextMessage.setText(R.string.title_tba);
getFragmentManager().beginTransaction()
.show(tbaFragment)
.hide(homeFragment)
.hide(delphiFragment)
.commit();
return true;
}
return false;
}
};
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// Check if the key event was the Back button and if there's history
if ((keyCode == KeyEvent.KEYCODE_BACK) && mWebView.canGoBack()) {
mWebView.goBack();
return true;
}
// If it wasn't the Back key or there's no web page history, bubble up to the default
// system behavior (probably exit the activity)
return super.onKeyDown(keyCode, event);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextMessage = (TextView) findViewById(R.id.message);
BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
if (savedInstanceState == null) {
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.add(container, homeFragment);
ft.add(container, delphiFragment);
ft.add(container, tbaFragment);
ft.hide(delphiFragment);
ft.hide(tbaFragment);
ft.commit();
}
}
}
And here is my delphiFragment class
package com.thirdspare.android.ckcyberpackapp;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import static com.thirdspare.android.ckcyberpackapp.MainActivity.mWebView;
public class DelphiFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup parentViewGroup, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.frag_delphi, parentViewGroup, false);
mWebView = (WebView)view.findViewById(R.id.wbvCD);
// Enable Javascript
WebSettings webSettings = mWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
mWebView.setWebViewClient(new WebViewClient());
mWebView.loadUrl("https://www.chiefdelphi.com/forums/portal.php");
return view;
}
}
Which is almost identical to the other webview fragment
In MainActivity your are adding three fragments and hide two other fragments. Later on your demand your hiding and showing fragment. Based on my understanding hide will disable fragment view from window, but it is still in running state of its lifecycle. So the static mWebview has only one of the fragment intstance all the time, mWebview didn't change based on your selection.
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