Develop Reference

How to use Preference.setLayoutResource() using object

I am attempting to set a Preference layout in code using setLayoutResource() . But this method requires an int id. I have a preset RelativeLayout that I want to pass as an argument, but I get an error saying Preference cannot be applied to RelativeLayout. I suspect it is because I am not passing an R.layout.id. I need this to work because I will addPreferences dynamically using instances of the same layout with different attribute setting. How can I make this work? Thank you. Sample code below.
rLay=(RelativeLayout)View.inflate(Context,R.layout.account_item, null);
nameView =(TextView) rLay.findViewById(R.id.account_name);
numberView =(TextView) rLay.findViewById(R.id.number_name);
pView = new Preference(Context);
pView.setLayoutResource(rLay); ///ERROR HAPPENS HERE///

If you use same layout with dynamically-changing data,
you can create AwesomePreference extends Preference,
then override onBindView(View) to changing TextView's text or something like that.
This is working like ListView's adapter#getView().
Also don't forget to call Preference#notifyChanged() if you changed bound data.
hope this will help.

Automatically/dynamically update TextView text in Android

I have an android app that I have decided to rewrite, one of the reasons for the rewrite is because I could have 10+ TextViews with text set based on a variable in a class e.g.:
MyClass myClass = new MyClass();
myClass.myNumber = 5; // inside MyClass - public int myNumber;
LinearLayout mainLayout = (LinearLayout) view.findViewById(R.id.mainLayout);
TextView myTextView = new TextView(getActivity()); //In a fragment
myTextView.setText(String.format("myNumber currently has a value of %d", myClass.myNumber));
mainLayout.addView(myTextView);
return view;
Up until now I have been using .setOnClickListener on the buttons/views that change myNumber, to set the text of the view again when the value of myNumber changes, which then calls .invalidate() to redraw the TextView, this has worked fine, but I use this method very heavily and code is getting quite repetitive and changing one integer can affect quite a lot of views (all of which use it differently - such as different wording, or a calculation (e.g. myNumber * 2)). I guess it's because it's made an immutable string in the TextView.
I have tried to create a custom TextView that implements Observer (making MyClass extend Observable) and in the update method I can get it to invalidate itself for the refresh, but it still has the same text. I have also tried creating single element arrays, in an attempt to pass the reference not the value in the hope that when it is changed and then the view is invalidated it will pick up the new value but the text still ends up remaining the same.
How can I get a TextView that will auto update when the value of myNumber has changed? Some sort of binding?

Bindroid works perfectly for this, just a note for users, using fragments the sample application is using this from an Activity so the bind method using Activity is called, so in the fragment I was using getActivity() which caused it to not work properly, digging around in the library I found a bind method that takes a View and passed in my view which gets inflated in the fragment and it works great!!! This is super easy to integrate btw it was just me not getting it!

Adding Custom ImageButton to layout in Android causes error

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.

Android - Text Switcher

I'm trying to add a text switcher dynamically but I get the error:
The method setFactory(ViewSwitcher.ViewFactory) in the type ViewSwitcher is not applicable for the arguments...
Here's my code:
TextSwitcher ts = (TextSwitcher) new TextSwitcher(this);
ts.setFactory(this);
Animation in = AnimationUtils.loadAnimation(this,android.R.anim.fade_in);
Animation out = AnimationUtils.loadAnimation(this,android.R.anim.fade_out);
ts.setInAnimation(in);
ts.setOutAnimation(out);

The setFactory method expects a ViewSwitcher.ViewFactory type argument and not Activity (which I presume is your this.)
You have 3 options:
you can implement your own ViewSwitcher.ViewFactory. you can see an example here.
you can use ViewSwitcher.addView to dynamically add your child views
you can define the child views in your layout xml
Either one should work OK for you.

Your activity class needs to implement android.widget.ViewSwitcher.ViewFactory interface.

How do you get a view reference from a class that doesn't extend Activity?

I want to have a class "Utils", that will have several methods used all over my code. For example, I have a top bar with a textview and two ImageButtons that must display different texts and icons on different activities.
I find myself writing stuff like this on every activity:
(TextView) topBarText = (TextView) findViewById(R.id.topBarText);
topBarText.setText(R.id.mytextForThisView);
I'd like to findViewById once in my whole app, and call a method setupTopBar(String text, R.id.iconForImageButton1, R.id.iconForImageButton2), or even pass the current Activity's id and let the method figure out what to show in the text and images.
I created the class Util, but it doesn't extend Activity. The problem is that if it doesn't, findViewById isn't accessible, so I can't use it.
What's the pattern to do something like this in Android?

Your helper methods should look like
public static void setTopBarText(Activity act, int textId){
(TextView) topBarText = (TextView)act.findViewById(R.id.topBarText);
topBarText.setText(textId);
}
Then you can do a static import from Activity and call
setTopBarText(this, R.id.mytextForThisView);

The Answer is not good for some situation.
This is my method:
In your Activity:
YouCustomClassObject.passView((View)findViewById(R.id.aview));
Using parameter passing can solve this kind of problem.