Develop Reference

Viewing an image on a Android Fragment

I am having trouble showing an image from the drawable folder on to a fragment.
When I try to show do it, it comes up with a java.lang.NullPointerException.
any help would be appreciated.
This is my code,
public class Fragment4 extends Fragment {
public Fragment4() {
}
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate (R.layout.fragment4, container, false);
ImageView image = (ImageView)rootView.findViewById(R.id.image);
image.setImageResource(R.drawable.image123);
return rootView;
}
}
XML file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>

Your ImageView has no id. Set it as follows,
<ImageView
android:id="#+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

It is because you didn't add id attribute to the image in xml
Try this:
<ImageView
android:id="#+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

Programmatically setting TextView backgroundcolor in ExpandableListView

I am trying to set a simple backgroundcolor of a textview (lblTb1Head) which is part of a expandablelistview in a fragment.
Unfortunately I always get a nullpointerexception on below line and i cannot find the reason why?
Downvoters, pls be gentle, it`s been a long night for me, maybe too long.
txtGroup.setBackgroundColor(Color.parseColor("#E8EBED"));
Declaration of txtGroup:
public class Tb1_KltGegevens extends Fragment {
private View v, mProgressView;
private TextView txtGroup;
...
}
My fragments onCreateView:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
v = inflater.inflate(R.layout.tb1_kltgegevens, container, false);
ExpandList = (ExpandableListView) v.findViewById(R.id.expListViewTb1);
txtGroup = (TextView) v.findViewById(R.id.lblTb1Head);
SharedPreferences settings1 = getActivity().getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
newTheme = settings1.getInt("themeCustom", 0);
if (newTheme == THEME_LIGHT) {
txtGroup.setBackgroundColor(Color.parseColor("#E8EBED"));
}
return v;
}
My layout file for tb1_kltgegevens:
<LinearLayout 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:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:layout_margin="8dp"
tools:context=".MainActivity" >
<ExpandableListView
android:id="#+id/expListViewTb1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ExpandableListView>
</LinearLayout>
The tb1_group.xml with the textview:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="8dp">
<TextView
android:id="#+id/lblTb1Head"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"
android:textSize="17dp" />
</LinearLayout>

if your TextView lblTb1Head is in the Layout tb1_group.xml, then you should be inflating the layout view as:
v = inflater.inflate(R.layout.tb1_group, container, false);
Do this and then txtGroup = (TextView) v.findViewById(R.id.lblTb1Head); won't return null.

Material design stepper control

Could someone give me an idea how to begin implementing vertical, non-linear stepper control described in the Android Material Design guide here:
http://www.google.com/design/spec/components/steppers.html

you can check this library , however this is still in development.
just extend the mobileStepperSimple class and implement the methods init,onFinished.
you can add the steppers as fragments by extending the stepperFragment and implement onNextButtonHandler to handle next button click.
check the demo for more usage.
any contributions and optimization will be helpful.

Well not exactly the same but as per my requirement, I developed custom VERTICAL STEPPER.
Below is the source code of whole demo.
activity_main.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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="10dp"
android:divider="#android:color/transparent"
android:dividerHeight="0dp"/>
</LinearLayout>
Single Item for List(Design your single item of your stepper in raw.xml file)
raw.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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="25dp"
android:orientation="vertical">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="vertical">
<ImageView
android:id="#+id/iv_upper_line"
android:layout_width="wrap_content"
android:layout_height="20dp"
app:srcCompat="#drawable/order_status_line" />
<ImageView
android:id="#+id/iv_circle"
android:layout_width="30dp"
android:layout_height="30dp"
app:srcCompat="#drawable/circle_o" />
<ImageView
android:id="#+id/iv_lower_line"
android:layout_width="wrap_content"
android:layout_height="20dp"
app:srcCompat="#drawable/order_status_line" />
</LinearLayout>
<LinearLayout
android:id="#+id/ly_status"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_marginLeft="10dp"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="#+id/tv_status"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:text="Order Rcived"
android:layout_gravity="left"
android:textSize="18sp"
android:textStyle="bold" />
<LinearLayout
android:id="#+id/ly_orderstatus_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical|top"
android:orientation="horizontal">
<ImageView
android:id="#+id/imageview"
android:layout_width="20dp"
android:layout_height="20dp"
app:srcCompat="#drawable/ic_restore_black" />
<TextView
android:id="#+id/tv_orderstatus_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical|top"
android:text="8:30am,Jan 31,2018"
android:textSize="18sp" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
</LinearLayout>
MainActivity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
orderStatusList();
}
private void orderStatusList() {
ArrayList<OrderStatusModel> arrayOfStatus =OrderStatusModel.getStoreDetail();
OrderStatusAdapter adapter = new OrderStatusAdapter(this, arrayOfStatus);
ListView listView = (ListView) findViewById(R.id.list);
listView.setAdapter(adapter);
}
Adapter Class
class OrderStatusAdapter extends ArrayAdapter<OrderStatusModel> {
Context context;
ArrayList<OrderStatusModel> order_status;
boolean isOn = false;
public OrderStatusAdapter(Contextcontext,ArrayList<OrderStatusModel>order_status{super(context, 0, order_status);
this.context = context;
this.order_status = order_status;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
// Check if an existing view is being reused, otherwise inflate the view if(convertView==null)convertView=LayoutInflater.from(getContext()).inflate(R.layout.raw,parent,false);
}
// Get the data item for this position
OrderStatusModel order_status_data = getItem(position);
// Lookup view for data population
ImageView iv_upper_line = (ImageView)
convertView.findViewById(R.id.iv_upper_line);
ImageView iv_lower_line =(ImageView)
convertView.findViewById(R.id.iv_lower_line);
final ImageView iv_circle = (ImageView) convertView.findViewById(R.id.iv_circle);
TextView tv_status = (TextView) convertView.findViewById(R.id.tv_status);
TextView tv_orderstatus_time =(TextView)
convertView.findViewById(R.id.tv_orderstatus_time);
LinearLayout ly_orderstatus_time = (LinearLayout)
convertView.findViewById(R.id.ly_orderstatus_time);
LinearLayout ly_status = (LinearLayout) convertView.findViewById(R.id.ly_status);
// Populate the data into the template view using the data object
tv_status.setText(order_status_data.getTv_status());
tv_orderstatus_time.setText(order_status_data.getTv_orderstatus_time());
if(position == 0){
iv_upper_line.setVisibility(View.INVISIBLE);
}
else if (position == order_status.size()-1){
iv_lower_line.setVisibility(View.INVISIBLE);
ly_orderstatus_time.setVisibility(View.GONE);
}
convertView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
iv_circle.setBackgroundResource(R.drawable.bullseye);
Toast.makeText(context, "You Clicked at
item"position,Toast.LENGTH_SHORT).show();
}
});
// Return the completed view to render on screen
return convertView;
}
}
Model Class
private String tv_status;
private String tv_orderstatus_time;
public OrderStatusModel(String tv_status, String tv_orderstatus_time) {
this.tv_status = tv_status;
this.tv_orderstatus_time = tv_orderstatus_time;
}
public String getTv_status() {
return tv_status;
}
public void setTv_status(String tv_status) {
this.tv_status = tv_status;
}
public String getTv_orderstatus_time() {
return tv_orderstatus_time;
}
public void setTv_orderstatus_time(String tv_orderstatus_time) {
this.tv_orderstatus_time = tv_orderstatus_time;
}
public static ArrayList<OrderStatusModel> getStoreDetail() {
ArrayList<OrderStatusModel> status = new ArrayList<OrderStatusModel>();
status.add(new OrderStatusModel("Order Rcived", "8:30am,Jan 31,2018"));
status.add(new OrderStatusModel("On The Way", "10:30am,Jan 31,2018"));
status.add(new OrderStatusModel("Delivered", "aaaaaa"));
return status;
}

Because no Support Library solution exists (still) I have tried several of these libraries in a recent project. My favourite (for appearance, smoothness and functionality) was This Project by "ernestoyaquello". I also added some options to it on My Fork.
The only thing to note with this, is that it does not use an 'adapter' class but instead uses a callback interface.
Demo Screen from Git:

android include change textView value

I include a layout in my fragment1.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<include
android:id="#+id/family_header"
layout="#layout/header" />
header xml code
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="50dip"
android:background="#33cc66"
android:orientation="horizontal" >
<ImageView
android:id="#+id/nav_back"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/nav_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_horizontal|center_vertical" />
<ImageView
android:id="#+id/nav_add"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
I want to change TextView "nav_text" value dynamically in my Fragment1.class . how to do it

you can create class that extends fragement....
public class DetailFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_rssitem_detail,
container, false);
return view;
}
public void setText(String item) {
TextView view = (TextView) getView().findViewById(R.id.detailsText);
view.setText(item);
}
}
in this class you can change value of textview dynemically.....please put your code here.so we can understand what is your actual problem.

Use this code in your fragment oncreateview method like this
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment1, container,false);
final LinearLayout headerLayout= (LinearLayout ) v.findViewById(R.id.family_header);
TextView txtHeaderText=(TextView)headerLayout.findViewById(R.id.nav_text);
txtHeaderText.setText("My New Text");
return v;
}
I hope it's work for you.

View overlapping each other

I have an activity in which my views (table and headertable) are overlapping
private ViewGroup createTable(ViewGroup root) {
// TODO Auto-generated method stub
TableLayout table = new TableLayout(getActivity());
table.setStretchAllColumns(true);
table.setShrinkAllColumns(true);
TableLayout headertable = new TableLayout(getActivity());
headertable.setStretchAllColumns(true);
headertable.setShrinkAllColumns(true);
/* Adding stuff to headertable which contains... */
/* ...table content I DO NOT WANT to scroll*/
root.addView(headertable);
for (int i = -2; i <= 100; i++) {
if (i > 0) {
/*Set up empty views*/
/*...3 empty views will be set*/
}
/* Adding stuff to table which contains... */
/* ...table content I WANT to scroll*/
}
ScrollView sv = new ScrollView(getActivity());
sv.addView(table);
root.addView(sv);
return root;
}
I basically broke a table into headertable and table. I want to scroll table but not headertable. However, my table(which should be below headertable), is overlapping it. Hence, as you can see above I added empty views(so it starts off below headertable(which has three rows)), but realized this would not work. As soon as I scrolled down, the empty views slide up and my headertable gets obstructed again.
All my views have been made programmatically. This activity is a fragment activity.
The XML file contains
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffffff" >
</FrameLayout>
Any help would be appreciated. Thanks in advance.

I don't know if it's the best way, but here's how I do it:
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<FrameLayout
android:id="#+id/pane"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
header_list.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/header"
android:layout_width="fill_parent"
android:layout_height="30dp"
android:layout_alignParentTop="true" />
<ListView
android:id="#id/android:list"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_below="#id/header" />
<TextView
android:id="#android:id/empty"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#id/header"
android:gravity="center" />
</RelativeLayout>
RecipeListFragment.java
public class RecipeListFragment extends ListFragment {
private TextView header;
private TextView empty;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.common_list, container, false);
header = (TextView) v.findViewById(R.id.header);
empty = (TextView) v.findViewById(android.R.id.empty);
header.setText(R.string.header_recipe);
empty.setText(R.string.empty_recipes);
return v;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// List code here
}
}
This code only has a single header line, but you can change that TextView to a TableLayout and then fill it the same way, giving you your header table and putting the list underneath it so that it won't scroll over the top of it.
Hope this helps!