I am new to android..
Is there any way to get the reference of active View loaded in the android...?
I want it some like this:::
View v=getTheActiveView();
bool b = v.getKeepScreenOn();//
I want this method getTheActiveView to be implemented.
This view may be Android home screen,or some other Application's view...
I dont want setter methods,just getter methods like getKeepScreenOn,etc is enough...
Pardon me if it is blunder...
If you added a tag to the view in question (whether you inflated it from an xml layout file or created it programmatically), you can call findViewById(int id) on the Activity that the view is currently displayed in to get a reference to it. Hope this is what you meant.
Related
i want to find the position of the view which is the part of the list-view's custom XML file. How can find the position of the views. Can i automatically perform onItemClick?
I face this difficulty. In my case when i click on textview which is part of list-view's custom XML file then the position is right, but when i click on the button which is the part of list-view's custom XML file then it always gives first position.
After i have to decided to perform automatic onItemClick and store all the values of clicked position into another declared variable which is below.
See the image i used kotlin language instead of java. I stored all the map values into another variable which is declared above with public access specifier.
[Now when i perform operation on Button click i use
lvShayari.performItemClick(v, lvShayari.getPositionForView(v), lvShayari.selectedItemId)
this statement in which lvShayari is listview and performItemClick() method perform the onItemClick automatically when we clicked on button. Here v is the view, lvShayari.getPositionForView(v) method gives the position of v in my case it is button.]2
check out below code , hope it will help you:
listView.onItemClickListener = AdapterView.OnItemClickListener { adapterView, view, position, id ->
Toast.makeText(this, "Click on: " + position, Toast.LENGTH_SHORT).show()
}
for more Details follow this link
#Suvidha Malaviya
Make your own custom adapter for your listview with one interface in which there is one method with three parameters namely View, Position, Model class of your list which you are passing in your adapter.
After making this interface initialize that interface in your adapter and set that interface method in your view click event.
Now set this interface in your activity or fragment where you are using your custom adapter and get the value which you want...
For example, see below link in which there is explain how to use custom listener in list view adapter. Here you have to just make your own click listener in which you have to pass three parameters which I have mention above.
Try it. I hope you will resolve your issue...
I am new in android.I have a simple doubt,Is there any way to get id of a widget from some layout without set it as content view ?? I am looking to invisible a view from a class .I used the code
View b = findViewById(R.id.id2);
b.setVisibility(View.GONE);
But error in "id",is it possible to get ids if widget from a java class without set as contentview ?? please help me. Thanks in advance :)
You can inflate the views separately and then use findViewById on the root of the inflated layout.
// inside of Activity, you can use 'this' for the context
LayoutInflater inflater = LayoutInflater.from(context);
View root = inflater.inflate(R.layout.some_layout);
// from your example
View b = root.findViewById(R.id.id2);
b.setVisibility(View.GONE);
At this point however these views are not part of your Activity's view hierarchy and will not be seen by the user. You will have to add them either by using setContentView(root) or by finding a ViewGroup in the current view hierarchy and calling viewGroup.addView(root).
You can do it this way
Button filterButton = new Button(YourActivity.this);
filterButton.setVisibility(filterButton.GONE);
onCreate(Bundle) is where you initialize your activity. Most importantly, here you will usually call setContentView(view) with a layout resource defining your UI, and using findViewById(int) to retrieve the widgets in that UI that you need to interact with programmatically.
See below link :-
Why findViewById() is returning null if setcontentview() is not called?
'But error in "id",is it possible to get ids if widget from a java class without set as contentview ?? '
You have to create dynamic view then you do not have need to call setcontentview.
how to set setContentView?
Is there a way to set setContentView(int id) dynamically?
I will start by saying this, while I have some Java training, is my first foray into development for Android.
What I have done is created a custom ImageButton called MapCell that is basically an ImageButton that holds a few extra pieces of information, and it compiles fine.
My problem comes when I want to procedurally create a MapCell in the relevant Activity and add it to my TableLayout which is defined in the xml and has the id 'mapTable'. The relevant bit looks like this:
Random randy = new Random();
MapCell n = new MapCell(randy.nextInt(4), this); //the random number is part of my extra info
findViewById(R.id.mapTable).addView((View)n, 20, 20); //add cell to display
I get one error out of that:
The method addView(View, int, int) is undefined for the type View
Which to me sounds like utter nonsense. I put that View cast in there as desperation after I got this same error with n sitting by itself and nothing changed (Obviously my MapCell is already a View since it extends ImageButton).
I hope a new pair of eyes can tell me what this is about, since I've checked for similar problems and I didn't find any quite like this. Let me now if you need to see more code.
The method findViewById returns a View and the View class doesn't have the method addView(this method is implemented in the ViewGroup and its subclasses). Instead you should write:
((TableLayout)findViewById(R.id.mapTable)).addView(n, 20, 20);
I've cast the return of the findViewById method in a class that actually has the addView method.
You got this problem because method findViewById(R.id.mapTable) returns View object.
In android you can't add one View to another.
You can use addView function with ViewGroup, and all LinearLayout (etc.) objects.
I have a set of View instances that each represent some different data object (derived from Java.Lang.Object). I associate each view with its data object by setting the view's tag reference. The views can generate context menus, and in the onCreateContextMenu function I can get the source view and then get the data object from its tag.
My problem is that I can't find a way to associate the data object with the created menu or menu item such that I can get the data item in onContextItemSelected().
How do I propagate the data item to onContextItemSelected()?
UPDATE
From the link posted by #asktomsk it looks like what I want to do is only possible (without a lot of subclassing) if the originating view is a ListView. Having also read this on the android developer site I suspect that long-tough context menus are probably not advisable anyway, and that I should find a different mechanism.
Check the MenuItem.getMenuInfo() data. It contains information about context menu caller.
Some explanation you may found here:
Identifying the view selected in a ContextMenu (Android)
I'm new to Android and find it brutal (there seems to be an near infinite number of details and dependencies to remember).
Anywho, I got the TextSwitcher1 example app working, which uses ViewSwitcher. I'm assuming ViewSwitcher is the way to go, need to either display a map or a table, user can pick, and switch back and forth.
So I created my MapActivity in another application, seems to work. Next integrate into main app. So, call
View v = findViewById(R.layout.mapview);
and then
mSwitcher.addView(v);
except "v" is null. Why? Do I create the activity? But I don't want to show it yet. Is there such a call as "create activity but hide it until needed"? Or am I barking up the wrong tree?
Thanks for any insight.
The findViewById function returns a View based on an ID resource (R.id.something) for whatever view you have loaded in your activity (using setContentView(R.layout.main)). In your sample code, you're using a layout resource (R.layout.mapview). You should inflate the XML file, which will return a View that you can use to add to the ViewSwitcher.
Example Code:
LayoutInflater vi = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = vi.inflate(R.layout.mapview, null);
mSwitcher.addView(v);
However, you should be able to define everything in your XML file and not have to manually add the pages to your ViewSwitcher. Here's some example code on how to do that: http://inphamousdevelopment.wordpress.com/2010/10/11/using-a-viewswitcher-in-your-android-xml-layouts/