During Tablayout practices i am follow this code from link. but problem is while i am current tab show next tab Toast and Log-cat.Here is my code
ScrollableTabsActivity.java
package info.androidhive.materialtabs.activity;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import java.util.ArrayList;
import java.util.List;
import info.androidhive.materialtabs.R;
import info.androidhive.materialtabs.fragments.EightFragment;
import info.androidhive.materialtabs.fragments.FiveFragment;
import info.androidhive.materialtabs.fragments.FourFragment;
import info.androidhive.materialtabs.fragments.NineFragment;
import info.androidhive.materialtabs.fragments.OneFragment;
import info.androidhive.materialtabs.fragments.SevenFragment;
import info.androidhive.materialtabs.fragments.SixFragment;
import info.androidhive.materialtabs.fragments.TenFragment;
import info.androidhive.materialtabs.fragments.ThreeFragment;
import info.androidhive.materialtabs.fragments.TwoFragment;
public class ScrollableTabsActivity extends AppCompatActivity {
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_scrollable_tabs);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new
ViewPagerAdapter(getSupportFragmentManager());
adapter.addFrag(new OneFragment(), "ONE");
adapter.addFrag(new TwoFragment(), "TWO");
adapter.addFrag(new ThreeFragment(), "THREE");
adapter.addFrag(new FourFragment(), "FOUR");
adapter.addFrag(new FiveFragment(), "FIVE");
adapter.addFrag(new SixFragment(), "SIX");
adapter.addFrag(new SevenFragment(), "SEVEN");
adapter.addFrag(new EightFragment(), "EIGHT");
adapter.addFrag(new NineFragment(), "NINE");
adapter.addFrag(new TenFragment(), "TEN");
viewPager.setAdapter(adapter);
}
private class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFrag(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
activity_scrollable_tabs.xml
<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: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.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="scrollable"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
OneFragment.java
package info.androidhive.materialtabs.fragments;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import info.androidhive.materialtabs.R;
public class OneFragment extends Fragment{
public OneFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_one, container, false);
}
}
fragment_one.xml
<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"
tools:context="info.androidhive.materialtabs.fragments.OneFragment">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/one"
android:textSize="40dp"
android:textStyle="bold"
android:layout_centerInParent="true"/>
</RelativeLayout>
Second and Third fragment code is same as mention as Tab 1 code. i just add following code at third Tab code onCreateView method
Toast.makeText(getContext(), "3 fragment", Toast.LENGTH_SHORT).show();
Log.d(TAG, "onCreateView: 3 fragment ");
i am getting following output
as you can show fragment 3 Toast come at second fragment i also notice third fragment log-cat also come at second fragment. i don't know what wrong happen but i notice all time at my current Tab position upcoming Tab Toast and log-cat
show and it will happen at any position at tablayout tab. i am also try other tutorials and other method for create scrollable Tablayout but in all practices i am getting same type of problem. please help me to solve problem i just want my upcoming fragment can't start proceeding until i was visit.at the end sorry for bed formatting i am newbies.
You can check the current selected tab
#Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if (isVisibleToUser) {
// Show your toast here
}
}
You can use this method to know the currently displayed tab
The FragmentPagerAdapter creates the instance of the next fragment, before it gets used. Part of the lifecycle of the Fragment is called, before the Fragment is attached to the window and is visible.
Some info from Android docs about FragmentPagerAdapter says:
Implementation of PagerAdapter that represents each page as a Fragment that is persistently kept in the fragment manager as long as the user can return to the page.
The fragment of each page the user visits will be kept in memory, though its view hierarchy may be destroyed when not visible.
This is not a sufficient info, but basically it says, that the methods onCreateView() and onDestroyView() are not directly connected with the visibility of the Fragment to the user, so better think about placing your code in onResume() for example or use viewPager.addOnPageChangeListener() to get informed about the changing of pages.
Related
I have a problem with android a ViewPager setup with FragmentPagerAdapter and TabLayout
TabLayout works fine. But, the code in all tabs run simultaneously. I want the code in the currently selected tab to run
This is my activity
package francesco.prisco.siamostudenti.ui;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import java.util.ArrayList;
import java.util.List;
import francesco.prisco.siamostudenti.R;
import francesco.prisco.siamostudenti.ui.fragments.CalendarFragment;
import francesco.prisco.siamostudenti.ui.fragments.ChatFragment;
import francesco.prisco.siamostudenti.ui.fragments.EmailFragment;
import francesco.prisco.siamostudenti.ui.fragments.HomeFragment;
import francesco.prisco.siamostudenti.ui.fragments.ProfiloFragment;
public class HomeTabActivity extends AppCompatActivity {
// private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_tab);
// toolbar = (Toolbar) findViewById(R.id.toolbar);
// setSupportActionBar(toolbar);
// getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
setupTabIcons();
}
private void setupTabIcons() {
int[] tabIcons = {
R.drawable.ic_home,
R.drawable.ic_calendar,
R.drawable.ic_chat,
R.drawable.ic_email,
R.drawable.ic_profile
};
tabLayout.getTabAt(0).setIcon(tabIcons[0]);
tabLayout.getTabAt(1).setIcon(tabIcons[1]);
tabLayout.getTabAt(2).setIcon(tabIcons[2]);
tabLayout.getTabAt(3).setIcon(tabIcons[3]);
tabLayout.getTabAt(4).setIcon(tabIcons[4]);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFrag(new HomeFragment(), "HOME");
adapter.addFrag(new CalendarFragment(), "CALENDAR");
adapter.addFrag(new ChatFragment(), "CHAT");
adapter.addFrag(new EmailFragment(), "EMAIL");
adapter.addFrag(new ProfiloFragment(), "PROFILO");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFrag(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
// return null to display only the icon
return null;
}
}
}
And this is code of a fragment
package francesco.prisco.siamostudenti.ui.fragments;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;
import francesco.prisco.siamostudenti.R;
import francesco.prisco.siamostudenti.ui.HomeTabActivity;
public class ProfiloFragment extends Fragment {
public ProfiloFragment() {}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_profilo, container, false);
return rootView;
}
}
Help me please
Like #Mrugesh Thaker says, all of the Fragment lifecycle functions - onCreateView(), etc. are executed every time the View of a Fragment is inflated.
Here, the View of each Fragment is inflated every time it becomes the adjacent Fragment of the current Fragment page.
So, you should move the 'code each Fragment needs to execute' when it becomes the currently selected Fragment page into an OnPageChangeListener
In your HomeTabActivity, when you set up the ViewPager, add an
OnPageChangeListener to yourViewPager
private void setupViewPager(ViewPager viewPager) {
.
.
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener(){
public void onPageScrollStateChanged (int state){
}
public void onPageSelected (int position){
/*
* Define the action to be performed for each page.
* Variable 'position' is the index of the page in the ViewPager
*/
}
public void onPageScrolled (int position, float positionOffset, int positionOffsetPixels){
}
});
}
Learning Resource
Actually, view pager works like that. The main aim of view pager is to enable a user to have smooth swipe , so what it does is , it will create all the fragments that you gave at a time to have smooth swiping flow. This is actually the limitation of it because all the methods of fragment lifecycle are called at a time.
Hello I am currently working on a viewpage template using the following tutorial:
http://www.androidhive.info/2015/09/android-material-design-working-with-tabs/
I was able to add a filter as well as changing color for each tab but I am running into a weird issue. The template with a fab and I added a feature that whenever the fab is pressed it will add and extra tab and reload the tablayout. This method works great. However, when I tilt the device horizontally the view goes back to being only one tab (how it was when the application opened.) Any ideas why this would happened? I tried a few things including finishing the activity and restarting it but no luck. Thank you in advance.
JAVA:
package com.example.reasults.materialpagerdesign;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import java.security.cert.CertificateParsingException;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import android.app.Activity;
import com.example.reasults.materialpagerdesign.OneFragment;
public class MainActivity extends AppCompatActivity {
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
private LinkedList<String> tabs = new LinkedList<String>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (tabs.size() < 1) { tabs.add("ONE");};
//if (tabs.size() == 2) {Log.i("TEST", "here");}
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
tabs.add("Two");
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
/*Log.i("TEST", Integer.toString(tabs.size()));
tabs.add("Two");
Log.i("TEST", Integer.toString(tabs.size()));
Intent intent = new Intent(MainActivity.this, MainActivity.class);
finish();
startActivity(intent);*/
}
});
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
#Override
public void onPageSelected(int position) {
if (position == 0) {
toolbar.setBackgroundColor(getResources().getColor(R.color.colorPrimary));
tabLayout.setBackgroundColor(getResources().getColor(R.color.colorPrimary));
}
if (position == 1) {
toolbar.setBackgroundColor(Color.parseColor("#4DAC26"));
tabLayout.setBackgroundColor(Color.parseColor("#4DAC26"));
}
}
#Override
public void onPageScrollStateChanged(int state) {
}
});
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
//adapter.addFragment(new OneFragment(), "ONE");
for (int i = 0; i < tabs.size(); i ++){
adapter.addFragment(new OneFragment(), tabs.get(i));
}
viewPager.setAdapter(adapter);
}
private void setupViewPager2(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new OneFragment(), "ONE");
adapter.addFragment(new TwoFragment(), "Two");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
XML:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:fitsSystemWindows="true"
tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout android:layout_height="wrap_content"
android:layout_width="match_parent" android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar android:id="#+id/toolbar"
android:layout_width="match_parent" android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary" app:popupTheme="#style/AppTheme.PopupOverlay" />
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="scrollable"
app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<include layout="#layout/content_main" />
<android.support.design.widget.FloatingActionButton android:id="#+id/fab"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:layout_gravity="bottom|end" android:layout_margin="#dimen/fab_margin"
android:src="#android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
how can we add goBack function in webview fragment?
when I click BACK button, it quits from fragment, I want it not to finish, but load the old website.
I tried ,this link but changed some words and it s not working...
please help.
code is here;
FRAGMENT ACTIVITY;
package info.androidhive.materialtabs.activity;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.webkit.WebView;
import android.webkit.WebViewFragment;
import java.util.ArrayList;
import java.util.List;
import info.androidhive.materialtabs.R;
import info.androidhive.materialtabs.fragments.OneFragment;
import info.androidhive.materialtabs.fragments.ThreeFragment;
import info.androidhive.materialtabs.fragments.TwoFragment;
public class SimpleTabsActivity extends AppCompatActivity {
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_simple_tabs);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new OneFragment(), "ONE");
adapter.addFragment(new TwoFragment(), "TWO");
adapter.addFragment(new ThreeFragment(), "THREE");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
FRAGMENT LAYOUT;
<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: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.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="fixed"
app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
Override the onBackPressed method from your Activity.
From there try to find your current fragment and call a method from this fragment that will handle your web views action
Example (This code belongs to your Activity):
#Override
public void onBackPressed() {
if (getFragmentManager().findFragmentById(R.id.container) instanceof YourFragment) {
YourFragment currentFragment = (YourFragment) getFragmentManager().findFragmentById(R.id.container);
if (currentFragment != null) {
currentFragment.handleWebViewNavigation();
}
}
}
Actually you can not do directly inside the fragment. The onBackPressed can be overridden in the FragmentActivity. What you can do is:
Override the onBackPressed inside the activity.
When the onBackPressed is called, check if the instance of the current fragment is the instance showing the webview.
If it is, ask the fragment if the webview can go back.
if it is not, call the super or whatever you need
for more detail visit this How to add "Go Back" function in WebView inside Fragment?
I'm following this tutorial here trying to add fragments to a tabbed Android app but it doesn't accept more than one fragment when I do it.
Also, I'm not sure if I should reference the fully qualified fragment name (e.g. com.mycompany.calcthis.calcfragment) or the short fragment name (e.g. CalcFragment).
What's happening is if I accept the Android Studio red bulb help to refactor the code for adding one of the fragments inside the adapter.addFrag(new fragment name(), "title") clause, it causes the other to be considered an error and it immediately underlines the other one as an error. It only accepts one of the two fragments without error. Weird!
Here's my code:
package thirtyeightdreams.com.calcthis;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import java.util.ArrayList;
import java.util.List;
public class Calculate extends AppCompatActivity {
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calculate);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFrag(new CalcFragment(), "Calculate");
adapter.addFrag(new TogetherFragment(), "Together");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFrag(PayForFragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
Here's a screen shot of the tip being offered. Notice both fragments are underlined with a red line:
So I accept the tip to refactor the code and it fixes that one:
But then if I accept the same tip code for the line that is still red, the other one that I just fixed becomes red.
So I'm trying to understand how to fix it so I can have multiple fragments listed here.
My overall goal is to have a particular fragment appear when a particular tab is clicked on.
Thanks
Try importing android.support.v4.app.Fragment
Try to import all of your fragments
using android.support.v4.app.Fragment;
I'm following this tutorial: Android Material Design Using Tabs
Infos:
Android API Level 21
Dependecies are added to graddle file
compile 'com.android.support:appcompat-v7:23.0.1' and
compile 'com.android.support:design:23.0.1'
}
The method "findViewById" cannot be resolved. I tried to follow this answer Cannot resolve method 'findViewById(int)' in Fragment, but this AppCompatActivity use OnCreateBundle instead OnCreateView, then i can't get the View object...
What is wrong with this code ? I'm missing some import?
package info.androidhive.materialtabs.activity;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import java.util.ArrayList;
import java.util.List;
import info.androidhive.materialtabs.R;
import info.androidhive.materialtabs.fragments.OneFragment;
import info.androidhive.materialtabs.fragments.ThreeFragment;
import info.androidhive.materialtabs.fragments.TwoFragment;
public class MainActivity extends AppCompatActivity {
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new OneFragment(), "ONE");
adapter.addFragment(new TwoFragment(), "TWO");
adapter.addFragment(new ThreeFragment(), "THREE");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
This is the "Error" that Android Studio show but i got 0 erros in logevent window
You appear to be running into the corrupt cache bug in Android Studio.
This happens to me a LOT when adding custom views with a custom namespace. If you added any custom views, this could be your issue.
To fix: File > Invalidate Caches / Restart
That should reindex everything and allow for auto-completion to work, as well, your findViewById() should work. I reviewed the code and do not see any errors.
AppCompatActivity extends FragmentActivity which extends Activity which has findViewById() method.
So it shouldn't be a problem to get the method.
I believe it's IDE bug.
Try to close your IDE and reopen the project.
Worked for me, perfectly.
Update your build tools version to the latest 27.0.3, after trying all solutions this is what worked for me.
in app -> build.gradle
buildToolsVersion '27.0.3'
rebuild and hope it works for you too