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"Cannot resolve method getResources" when trying to execute getResources in non-activity method using method widely advocated here

I have been trying to use getResources in a non-activity class. I found some advice on how to do so here. To use one of the suggested ways, by Lilzilala, (there are multiple, but mostly suggest the same thing), I have created a special class, used this to specify the resources as "res", and then instantiated this class using "new" in a line which invokes "getResources".
However, I'm getting a "cannot resolve method getResources" error on "getResources". I'm a bit of a noob, but don't know why this is happening. From what I can tell, this error happens when there simply isn't a resource with that name available. Which makes me think maybe Resources doesn't contain getResources() by default?
class executeTrimmer<Resdefine> {
public class ResDefine {
private Resources res;
public ResDefine(Resources res)
{
this.res = res;
}}
Bitmap img1 = BitmapFactory.decodeResource(new ResDefine(getResources()),
R.drawable.bmpname);
}
EDIT - following suggestions that I add context, I have tried this:
class executeTrimmer<Resdefine> {
private static Context context;
public executeTrimmer(Context context){
this.context = context;
}
public class ResDefine {
private Resources res;
public ResDefine(Resources res)
{
this.res = res;
}}
Bitmap img1 = BitmapFactory.decodeResource(new ResDefine(executeTrimmer.context.getResources),
R.drawable.bmpname);
But this still brings up error "cannot resolve symbol getResources". I've tried multiple different ways to pass context to it, and consistently faced the same error.

As you can see in the official documentation, "getResources" is Context's method, therefore you can't call it out from nowhere, neither statically. This method requires a context instance.
In your case you must at least pass a context to your class to be able to invoke it as next:
context.getResources()
I think you got confused from seen it being directly called inside Activities without a prefixed context, but as all Activities are actually a context, this is why there is no prefix.
To clarify. When called inside an activity, this:
getResources()
is the same as this:
this.getResources()
where the prefix "this." refers to the activity, which in turn is a context by itself.
On the other hand your code should be like next, without the ResDefine class. And notice that the decodeResource call is required to be inside a method and not at class level scope (this is not allowed in Java). And in fact you don't even need to use a context, so pass instead the Resources instance from the caller's class which is supposed to hold the context:
public class executeTrimmer {
private final Resources res;
public executeTrimmer(final Resources res) {
this.res= res;
}
public void loadBitmap()
Bitmap img1 = BitmapFactory.decodeResource(this.res, R.drawable.bmpname);
........
}
}
And for the caller, next a very naive example, so may get an idea:
public class MainActivity extends Activity {
#Override
protected void onCreate(#Nullable final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
new executeTrimmer(this.getResources()).loadBitmap();
}
}

In the MainActivity java, how to call the anko class directly?

I used the anko library to create a login view.
class SingInView : AnkoComponent<SingleInActivity> {
override fun createView(ui: AnkoContext<SingleInActivity>) = with(ui) {
verticalLayout {
lparams(width = matchParent, height = matchParent)
textView("Member Login")
editText {
hint = "E-mail"
}
editText {
hint = "PassWord"
}
button("Login")
}
}
}
and SingleInActivity.kt
class SingleInActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState)
SingInView().setContentView(this)
and MainActivity.java
public class MainActivity extends AppCompatActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
startActivity(new Intent(this, SingInView.class));
finish();
}
}
current My app MainActivity -> SingleInActivity -> SingInView .
of course it can be made simply.
but there is a condition
1. MainActivity is java (kotlin prohibition)
2. use only MainActivity, SingInView.
How to solve this problem?
How to call the Anko class directly from a Java class

If you dig through the Anko source code you'll quickly find this:
interface AnkoComponent<in T> {
fun createView(ui: AnkoContext<T>): View
}
And from the wiki (where MyActivityUI is the component): MyActivityUI().setContentView(this). Now, the AnkoComponent is just an interface and the setContentView method is an extension function that returns createView.
Anyways, the setContentView extension function passes the last variable of the AnkoContextImpl as true. The last variable is whether or not to actually set the content view, which is the reason the activity is passed in the first place.
TL;DR (and possibly more sensible summary of my point):
The component is not an Activity
The setContentView method is not a replacement for setContentView in an Activity; just a wrapper for it.
And since it isn't an activity, you can't use an intent into it. And, as a result of that, you cannot use it standalone. You need an activity. Now, you can of course use the regular approach, but there's also another way. Since the AnkoComponent itself doesn't have any fields, it can be serialized without much trouble. Just to clarify: some fields can be serialized even if it isn't serializable (all though some classes like Context cannot be serialized). Anyways, you create an activity:
class AnkoComponentActivity : AppCompatActivity(){//Can be a regular Activity too
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState);
val component = intent.getSerializableExtra("uiComponent") as AnkoComponent<AnkoComponentActivity>//The type has to match this activity, or setContentView won't allow passing `this`
component.setContentView(this)//The context of the activity doesn't get passed until this point, which enables the use of this system.
}
}
Or it's equivalent in Java:
public class AnkoComponentActivity extends AppCompatActivity {
public void onCreate(Bundle sis){
super.onCreate(sis);
AnkoComponent<AnkoComponentActivity> component = (AnkoComponent<AnkoComponentActivity>) getIntent().getSerializableExtra("uiComponent");
org.jetbrains.anko.AnkoContextKt.setContentView(component, this);//For reference, this is how you call Kotlin extension functions from Java
}
}
Note that any UI component sent to this class has to be declared with <AnkoComponentActivity>. In addition, the components have to implement Serializable. Otherwise they can't be passed through the Bundle. Alternatively, you can use ints or Strings as identifiers and use the value to pick which AnkoComponent to show.
All though, the absolutely easiest way is just creating one activity per component.
TL;DR: AnkoComponent is not an Activity, meaning you can't use intents into it. You have to use an Activity, but using Serializable enables you to pass the component through a bundle to an Activity made for manual creation of multiple AnkoComponents without specifying specific types.

Using getIdentifier() to Find ID of Image

I am trying to get id of an image by using following code.
public class MovieActivity extends ActionBarActivity {
private Context con;
String name = "test";
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
con = MovieActivity.this;
setContentView(R.layout.activity_movie);
}
public void updateScreen(){
int imageResource = con.getResources().getIdentifier("drawable/" + name , null, con.getPackageName());
}
}
When I run it, I get exception:
java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference
I thought the problem was Context so I added con variable which gets context when code runs. I made some researches and tried another methods but I got same exception every time. Can anyone help me?
EDIT: When I use the same code line in MainActivity, it works perfectly. But in another class, it fails.
public class SomeMovie extends MovieActivity { }
public class MainActivity extends ActionBarActivity {
protected void onCreate(Bundle savedInstanceState) {
SomeMovie movie = new SomeMovie();
movie.updateScreen();
}
}
SomeMovie class is child of MovieActivity class. I call the method on that. I debugged the code and noticed that Context is null when code gets into updateScreen() method. Is it wrong to use inheritance on activity classes?

Change
int imageResource = con.getResources().getIdentifier("drawable/" + name , null, con.getPackageName());
to
int imageResource = getResources().getIdentifier("drawable/" + name , null, con.getPackageName());
You are already in an Activity's context, so use it. (No need to use the this keyword to refer to it)
EDIT:
You are not defining a layout for the SomeMovie Activity, so its context is always null.
You have to define the activity's layout in its onCreate method :
public class SomeMovie extends MovieActivity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.somemoviexml);
...
}
}

Logging switch realization

This code:
public class MyActivity extends Activity {
private final boolean logging = getResources().getBoolean(R.bool.logging);
#Override
public void onCreate(Bundle savedInstanceState) {
if(logging) Log.d("my_log", "some text here");
// some onCreate code...
}
}
generates NullPointerException.
But this one:
public class MyActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
final boolean logging = getResources().getBoolean(R.bool.logging);
if(logging) Log.d("my_log", "some text here");
// some onCreate code...
}
}
Does not.
The main idea to switch logging in entire application with a boolean resource.
I can successfully declare this variable for every function in class, but can it be done for entire class just once?

Have you considered using a proper logging framework?
If you use the slf4j API you can write stuff like
log.debug("A={}, B={}", a, b)
where the switch is externally set in a well-documented way whether to generate a log statement or not. Also the slf4j {}-construct allows delaying the call to a.toString() and b.toString() until after the logging framework has decided that the log message actually needs to be generated.
slf4j is an API. You have several backends to choose from. For starters you can just pick the "simple" backend.
See http://slf4j.org/manual.html for an introduction.

Instead of putting value to string resource, I used static variable in special class.
public class constants {
public static final boolean logging = true;
}
so it can be accessed from any activity:
private boolean logging = constants.logging;

Passing a String Array Between Java Classes Android App

I am writing an Android app where I need to pass a string array between two classes. The string initializes fine and I can output the contents of the string fine in the one class but as I try to pass it to another class I get a Null Pointer Exception error. The following is the stripped down version of my code:
accelerometer.java:
public class accelerometer extends Service {
public String movement[];
public void onCreate() {
movement = new String[1000000];
}
public void updatearray() {
movement[arraypos]=getCurrentTimeString();
//Toast.makeText(this, movement[arraypos] , Toast.LENGTH_SHORT).show(); //this correctly displays each position in the array every time it updates so I know the array is working correctly in this file
arraypos+=1;
}
public String[] getmovement(){
return movement;
}
}
wakeupalarm.java:
public class wakeupalarm extends Activity {
private TextView herestext_;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.wakeup);
herestext_ = (TextView) findViewById(R.id.TextView01);
accelerometer accelerometercall = new accelerometer();
String movearray[] = accelerometercall.getmovement();
herestext_.setText(movearray[2]);
}
}
I have a feeling I'm missing something very simple but any help would be greatly appreciated!
Thanks,
Scott

You're creating a new accelerometer class, which is completely uninitialized since there is no constructor, then you access its member. Of course it'll be null.
Not sure how your two classes are related, but if the activity is called by the service, then you need to pass the string through the intent (through an extra, for example).
Side note: Class names should always start with a capital letter. Method/variable names should have camel case, i.e. "updateArray". Also, you can format your code here by selecting it and pressing CTRL+K.

Your first problem, I think, is that you are creating an array with a million slots in it. Do you really mean to be doing that? It's going to take a lot of memory---quite possibly more than is available. You should instead look to having a Vector of Strings that you extend as necessary.