I'm trying to use .addView to add another LinearLayout to the ViewGroup.
I am getting the following error on LogCat:
05-21 16:23:04.096: E/AndroidRuntime(2086): FATAL EXCEPTION: main
05-21 16:23:04.096: E/AndroidRuntime(2086): java.lang.NullPointerException
05-21 16:23:04.096: E/AndroidRuntime(2086): at android.view.ViewGroup.addView(ViewGroup.java:3148)
05-21 16:23:04.096: E/AndroidRuntime(2086): at android.view.ViewGroup.addView(ViewGroup.java:3131)
This is the code being called:
final LinearLayout eventContainerSub =
(LinearLayout) findViewById(R.layout.event_container);
final LinearLayout eventContainer =
(LinearLayout) findViewById(R.id.eventContainer);
eventContainer.addView(eventContainerSub);
Here is the ViewGroup (the first linear layout):
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true"
android:id="#+id/eventContainer"
android:weightSum="100"
android:duplicateParentState="true">
And this is the (second) LinearLayout I'm adding to the (first one) LinearLayout above:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/eventContainerSub">
Both containers have the exact same name..eventContainerSub.
There is no eventContainer, change the view group to be the container as you planned..
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true"
android:id="#+id/event_container"
android:weightSum="100"
android:duplicateParentState="true">
and make sure the code is asking for the right Ids:
final LinearLayout eventContainerSub =
(LinearLayout) findViewById(R.layout.eventContainerSub);
final LinearLayout eventContainer =
(LinearLayout) findViewById(R.id.event_container);
I'd also suggest you first remove the SubContainer from the view if it got inflated, as that view already has a parent and you cannot attach the SubContainer to two parents.
Either leave the subcontainer from this file and create a new one, or remove from the parent and only then add to the ViewGroup you want.
Android layout replacing a view with another view on run time
Call removeView() on the child's parent first
Related
I am having my bottom navigation view inside a fragment. Below is the code
<RelativeLayout 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"
tools:context=".fragments.investors.InvestmentParentFragment">
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_navigation_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:itemIconTint="#drawable/nav_selector"
app:itemTextColor="#drawable/nav_selector"
app:menu="#menu/investments_bottom_nav_menu"
android:layout_gravity="bottom"
android:layout_alignParentBottom="true"
app:itemRippleColor="#color/secondaryLightColor"
android:background="#drawable/bottom_nav_background"
/>
</RelativeLayout>
When i click on an item in the bottom navigation view it navigates to a fragment. The problem am having is that when i navigate to a new fragment it opens the new fragment and the bottom navigation view disappears i would like it to work like the way where the bottom navigation view is in MainActivity and when i navigate to a new fragment it does not disappear it stays there and can operate like a tab layout
Here is what i have tried so in the fragment having the bottom navigation view but its not working. Inside onViewCreated method
Navcontroller navController = Navigation.findNavController(view);
bnvInvestments = view.findViewById(R.id.bnv_investments);
NavigationUI.setupWithNavController(bnvInvestments, navController);
I have a gridview in my app and i'm able to increase its height dynamically. But my issue is that every time i increase the height, the scrollbar scrolls to the center of the page. What could cause this issue ? Here is my code below :
Axml :
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:gravity="center"
android:background="#e1effa">
<GridView
android:id="#+id/gvPhones"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:verticalSpacing="5dp"
android:drawSelectorOnTop="true"
android:stretchMode="columnWidth" />
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
Cs :
_mySimpleItemLoader = new LoadRecords();
_mySimpleItemLoader.LoadMoreItems();
gvPhone = FindViewById<GridView>(Resource.Id.gvPhones);
_gridviewAdapter = new PhonesAdapter(this, _mySimpleItemLoader, this);
gvPhone.Adapter = _gridviewAdapter;
gvPhone.LayoutParameters.Height = 777 * gvPhone.Count;
But my issue is that every time i increase the height, the scrollbar scrolls to the center of the page.
When you open an Activity, some control needs to take focus. But in your .axml layout there's no designated control to take focus, the system chooses the first eligible control that wants focus.
When you set the android:focusableInTouchMode="true" property in your LinearLayout, your LinearLayout will be focused on start and your NestedScrollView won't scroll to the center of the page.
I'm trying to use WearableActionDrawer in my app. Previously I was using 'com.google.android.support:wearable:2.0.0-alpha1' and my layout looks like this:
<?xml version="1.0" encoding="utf-8"?>
<android.support.wearable.view.drawer.WearableDrawerLayout
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:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:rectLayout="#layout/rect_activity_main"
app:roundLayout="#layout/round_activity_main"
tools:context="com.example.grant.wearableclimbtracker.MainActivity"
tools:deviceIds="wear">
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id = "#+id/content_frame">
<android.support.wearable.view.GridViewPager
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.v4.widget.NestedScrollView>
<android.support.wearable.view.drawer.WearableNavigationDrawer
android:id = "#+id/top_navigation_drawer"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:background="#color/dark_grey"/>
<android.support.wearable.view.drawer.WearableActionDrawer
android:id="#+id/bottom_action_drawer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/grey" />
</android.support.wearable.view.drawer.WearableDrawerLayout>
After I switched to 'com.google.android.support:wearable:2.0.0' the behavior changed. The action drawer used to stay out of view until I swiped up to reveal the action menu, but now there is a peek view of the drawer that doesn't go away unless I open the menu and select something. Is this the intended behavior? It takes up a lot of real-estate:
Any advice would be much appreciated.
It was as I suspected, when NestedScrollingChild height matched the parentview, the action drawer peeks. The only way I could get it to hide was to increase the NestedScrollingChild view by 1dp:
// get the screen width
DisplayMetrics metrics = new DisplayMetrics();
getActivity().getWindowManager().getDefaultDisplay().getMetrics(metrics);
// set height of framelayout to be slightly larger than view
mSessionLayout = rootView.findViewById(R.id.sessionLayout);
mSessionLayout.setMinimumHeight(metrics.heightPixels+1);
I have an AsyncTask linked to a refresh Button (when I click on my refresh button my AsyncTask is called).
I have on my Layout a LinearLayout field for my ProgressBar :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:background="#color/grey">
<Button android:id="#+id/refresh_p"
android:text="#string/refresh_promo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#drawable/custom_button1"/>
<LinearLayout android:id="#+id/linearlayoutProgressBar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"/>
<ListView
android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:listSelector="#color/tabTransparent"
android:cacheColorHint="#00000000"/>
<!-- <ListView android:id="#+id/list_promo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>-->
</LinearLayout>
In my AsyncTask :
#Override
protected void onPreExecute()
{
super.onPreExecute();
pb = new ProgressBar(context);
LinearLayout ll = (LinearLayout) ((Activity) context).findViewById(R.id.linearlayoutProgressBar);
ll.addView(pb);
pb.setVisibility(View.VISIBLE);
}
#Override
protected void onPostExecute(ArrayList<HashMap<String, String>> promoList)
{
...
if (pb!=null)
{
pb.setVisibility(View.GONE);
((LinearLayout)pb.getParent()).removeView(pb);
}
}
The problem I have is when I make more than 2 clicks on my Refresh Button then Multiple ProgressBar are displaying into the screen.. I just want that the new ProgressBar replace the old at the same position ..
My guess is that you are probably starting your AsyncTask in a manner similar to this:
new RefreshTask().execute(params);
Instead of that, create an instance variable in your activity. Let's say this is named mTask and substitute the above code for the following call:
if(mTask != null && mTask.getState != AsyncTask.State.RUNNING){
mTask = new RefreshTask();
mTask.execute(params);
}
This way you will ensure that only one instance of your task is running at a given time and the user will have to wait until the refresh is finished before he can start a new refresh.
If you want the user to be able to cancel an existing refresh task and run a new one, you will have to cancel the old one before starting a new one:
if(mTask != null){
if(mTask.getStatus() == AsyncTask.Status.RUNNING){
mTask.cancel(true);
}
mTask = new RefreshTask();
mTask.execute(params);
}
This way the old task and it's ProgressBar will be properly replaced by the new one.
I am trying to set background for my List view . I have taken a image from the drawable and set it as background to the layout file then it is giving the result as following screen shot
and when i just remove the background am getting the thing which i required but no background.
and screen shot is
Is there is any other Syntax to set background for ListView.
And my Code for layout is
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView android:text="#+id/TextView01" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:id="#+id/label"
android:textColor="#FF0000"
android:textSize="30px"></TextView>
</LinearLayout>
And my java code and that is
String[] names = new String[] { "India", "Malaysia" };
// Use your own layout and point the adapter to the UI elements which
// contains the label
this.setListAdapter(new ArrayAdapter<String>(this, R.layout.screen3,
R.id.label, names));
}
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
// Get the item that was clicked
Object o = this.getListAdapter().getItem(position);
String keyword = o.toString();
if(keyword.equals("India"))
{
Intent ima1=new Intent(screen3.this,new21.class);
startActivity(ima1);
}
else
{
Intent ima2=new Intent(screen3.this,new22.class);
startActivity(ima2);
}
Toast.makeText(this, "You selected: " + keyword, Toast.LENGTH_LONG)
.show();
}
And lastly i need is I want the background image with proper listview showing one listitem after another. Thanks in advance
}
Try this code, Instead of extending ListActivity you can set layout that contains List View and separate layout for contents of List View.
Java Code :
public class Table_Layout extends Activity {
ListView list_view;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.table_layout);
list_view=(ListView)findViewById(R.id.list_view);
String[] names = new String[] { "India", "Malaysia" };
list_view.setAdapter(new ArrayAdapter<String>(this, R.layout.screen3,R.id.label, names));
}
}
Main XML that contains List View :table_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" android:background="#drawable/uploading">
<ListView android:layout_width="fill_parent" android:layout_height="fill_parent"
android:id="#+id/list_view"
/>
Then Contents of List View :screen3.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<TextView android:text="#+id/TextView01" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:id="#+id/label"
android:textColor="#FF0000"
android:textSize="30px"></TextView>
</LinearLayout>
Set you Background for the table_layout.xml so that it will applied for entire List View as you expected.
All looks well with your xml file. Try implementing the below mentioned:-
Make an image of the size you want your listview's each row of. And set it as the parent LinearLayout's background. Set:- android:layout_width="fill_parent" android:layout_height="wrap_content".
Hope this helps !! :)