Develop Reference

Android - getResources().getIdentifier replacement

In android I am looping through the database and assigning text and image:
Cursor res = myDb.getAllData();
while (res.moveToNext()) {
Actors actor = new Actors();
actor.setName(res.getString(1));
String th = res.getString(11);
Integer thumb = this.getResources().getIdentifier(th, "drawable", "mypackage");
actor.setThumb(R.drawable.th);
}
However Lint suggests not to use getIdentifier - Use of this function is discouraged because resource reflection makes it harder to perform build optimizations and compile-time verification of code.
In database column I have just the image name (string). How can I replace getIdentifier?
Even if I change the DB column maybe directly to R.drawable.imagename, it is still a string and for setThumb I need a drawable.

Ok, so the only solution what I've found is here https://stackoverflow.com/a/4428288/1345089
public static int getResId(String resName, Class<?> c) {
try {
Field idField = c.getDeclaredField(resName);
return idField.getInt(idField);
} catch (Exception e) {
e.printStackTrace();
return -1;
}
}
and then just calling:
int resID = getResId("icon", R.drawable.class);
This works very well, however some users reports, that after installing the app from Play store (not my app, but any with this method implemented and proguard enabled), after a while it will start throwing NoSuchFieldException, as more resources are mapped to the same class/field.
It can be caused by proguard but not sure. The solution is then to put the old way getResources().getIdentifier to the exception part of code.

You can try this approach:
Rename your resources as follow:
ressourceName00
ressourceName01
ressourceName02 .... and so on,
then use the methode below:
for (int i = 0; i < RessourceQtt; i++) {
Uri path1 = Uri.parse("android.resource://yourPackage Directories/drawable/ressourceName0" + i);
list.add(new CarouselItem(String.valueOf(path1)));
}

You can try this my code three way
// Show message and quit
Application app = cordova.getActivity().getApplication();
String package_name = app.getPackageName();
Resources resources = app.getResources();
String message = resources.getString(resources.getIdentifier("message", "string", package_name));
String label = resources.getString(resources.getIdentifier("label", "string", package_name));
this.alert(message, label);
set icon like that
private int getIconResId() {
Context context = getApplicationContext();
Resources res = context.getResources();
String pkgName = context.getPackageName();
int resId;
resId = res.getIdentifier("icon", "drawable", pkgName);
return resId;
}
this is also
//set icon image
final String prefix = "ic_";
String icon_id = prefix + cursor.getString(cursor.getColumnIndex(WeatherEntry.COLUMN_ICON));
Resources res = mContext.getResources();
int resourceId = res.getIdentifier(icon_id, "drawable", mContext.getPackageName());
viewHolder.imgIcon.setImageResource(resourceId);
I hope this code help for you.
public static int getIcId(String resN, Class<?> c) {
try {
Field idF = c.getDeclaredField(resN);
return idF.getInt(idF);
} catch (Exception e) {
throw new RuntimeException("No resource ID found for: "
+ resN+ " / " + c, e);
}}

Android: How check if a image exists in a IF clause?

I need to know how check if an image exists in R.drawable, It has to be dynamic so I have to use a string that gives me the name of the image.
I've tried with '!=null' or exist but it hasn't worked.... Help please!!!!!!!!!
titulo=bundle.getString("titulo");
textView = (TextView) findViewById( R.id.textView1);
textView.setText(titulo);
foto="f"+bundle.getString("numero")+"a";
System.out.println(foto);
flipper =(ViewFlipper) findViewById(R.id.vfFlipper);
this gives me the name of the image a need...
image = new ImageView(this);
image= new ImageView(this);
image.setImageResource(R.drawable.f00a1);
image.setScaleType(ScaleType.FIT_CENTER);
flipper.addView(image);
Whith this I can use the image but i need to use the variable "foto" so it can be dynamic
Thanks!

Everything in the R class is an integer - you can't create a string to represent a resource id. The closest you can get is to use getResources() then call...
getIdentifier(String name, String defType, String defPackage)
...this will allow you to find the integer which represents your resource based on the resource name.

you could use getResources to get an instance of Resources class. In Resources class, you have getDrawable If the resource is not found, you would get ResourceNotFoundException which also means the image is not found.
so the code will be something like this
Resource r = getResources();
Bool fileFound = true;
Drawable d = null;
try{
d = r.getDrawable(your_image_id);
}
catch(ResourceNotFoundException e){
fileFound = false;
}
if(findFound){
// Your operations
// set drawable to your imageview.
}

Thank you all! i mix the two answers and .. it work!
Resource r = getResources();
Bool fileFound = true;
Drawable d = null;
try{
d = r.getDrawable(getIdentifier(foto1, "drawable", getPackageName());
}
catch(ResourceNotFoundException e){
fileFound = false;
}
if(findFound){
// Your operations
// set drawable to your imageview.
}

getResources().getIdentifier("icon", "drawable", "your.package.namespace");
check for non zero value for above statement.
if(0)
//does not exists
else
//exists

private boolean isDrawableImageExists(String imgName) {
int id = getResources().getIdentifier(imgName, "drawable", getPackageName());
return id != 0;
}

Retrieving StringArray resource depending on the clicked button

I want to design a ListView that will be populated from a StringArray resource depending on which button was clicked. The array name will be retrieved and put into the getStringArray method like 'dynamically', after the button was clicked.
I'm trying this method to get the identifier by name:
getResources().getIdentifier(String name, String defType, String defPackage);
but when I am constructing the array name as a String made of clicked button ID and some other Strings like this:
Bundle extras = getIntent().getExtras();
Integer buttonId = extras.getInt("ButtonId");
String resourceName = "";
int resourceId = 0;
resourceName = "R" + buttonId.toString() + "WEEK" + "OUT";
resourceId = getResources().getIdentifier(resourceName, "array", this.getPackageName());
I get an error that there is no such resource and the getIdentifier method returns 0.
(The name of the resource is set to the same value as the resourceName).

Easier way to get view's Id (string) by its Id (int)

I have 24 buttons in my layout, all these buttons do something similar so I want to create a generic function. But first I need to know the name (xml id) of he button.
This the XML code of the button:
<Button
android:id="#+id/add_04"
android:layout_width="42dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="15dp"
android:background="#xml/zbuttonshape"
android:onClick="onClick"
android:text="#string/mas" />
I set android:onClick="onClick" for all the buttons.
In my activity I've create a new function onClick:
This the code I've tried:
public void onClick(View v) {
String name = v.getContext().getString(v.getId());
String name2 = context.getString(v.getId());
String name3 = getString(v.getId());
String name4 = getResources().getString(v.getId());
}
But when I try to get the name (in this case "add_04") I always get "false".
Finally I've found a solution with the following code:
import java.lang.reflect.Field;
String name5 = null;
Field[] campos = R.id.class.getFields();
for(Field f:campos){
try{
if(v.getId()==f.getInt(null)){
name5 = f.getName();
break;
}
}
catch(Exception e){
e.printStackTrace();
}
}
Is there an easier way to get this ID?

like this:
/**
* #return "[package]:id/[xml-id]"
* where [package] is your package and [xml-id] is id of view
* or "no-id" if there is no id
*/
public static String getId(View view) {
if (view.getId() == View.NO_ID) return "no-id";
else return view.getResources().getResourceName(view.getId());
}
I use this in view constructors to make more meaningful TAGs

The approach is misguided to begin with. If you want to associate a piece of arbitrary data (e. g. a string) with a view, that's what tag is for. The ID is numeric and it better stay that way. A word of caution though, tags are not unique in Android, watch for accidental tag collisions within the same view tree.
EDIT much later: the OP's issue was a case of an XY problem. That said, the question title alone is a legitimate question in its own right.

Edit:
You have to use
getResources().getResourceEntryName(int resid);
If you want to retrieve the entry name associated to a resId
or
You can use getIdentifier() to retriece a resource identifier for the given resource name.
For instance:
int id = this.getResources().getIdentifier("yourtext", "string", this.getPackageName());

You can check id of each button such way:
public void onClick(View v) {
switch (v.getId()) {
case R.id.add_04:
Toast.makeText(MainActivity.this, "1", Toast.LENGTH_LONG).show();
break;
case R.id.add_05:
Toast.makeText(MainActivity.this, "2", Toast.LENGTH_LONG).show();
break;
}
}

Use this Approach to get View Id by Programming .
<TextView
android:id="#+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
/>
String id=getResources().getResourceEntryName(textView.getId());
Toast.makeText(this,id,Toast.LENGTH_LONG).show();
You will get Result ; tv

You can put this toString() inside an Android View, it will return the String resource Id.
#Override
public String toString() {
Context context;
Resources r = null;
context = getContext();
if (context != null) {
r = context.getResources();
}
String entryName = null;
if (r != null)
entryName = r.getResourceEntryName(getId());
return entryName;
}

Kotlin version (from #gadget) as view extension:
val View.stringId: String
get() {
return if (this.id == -0x1)
"no-id"
else
this.resources.getResourceName(this.id)
}

It's a late answer but may useful someone looking out for a way to get the resource id (int) for any view / drawable / String programmatic.
image from res/drawable
int resID = getResources().getIdentifier("my_image",
"drawable", getPackageName());
view based on resource name
int resID = getResources().getIdentifier("my_resource",
"id", getPackageName());
string
int resID = getResources().getIdentifier("my_string",
"string", getPackageName());

The answer by #King of Masses is great. Here is my in Kotlin:
image from res/drawable
val viewId = context.resources.getIdentifier("my_image", "drawable", context.packageName)
view based on resource name
val viewId = context.resources.getIdentifier("my_textview_id", "id", context.packageName)
string
val viewId = context.resources.getIdentifier("my_string", "string", context.packageName)
Layout
val viewId = context.resources.getIdentifier("my_custom_layout", "layout", context.packageName)

Param in button to change activity

My button sends a parameter to the function.
<Button
android:id="#+id/tela1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Chinese Day"
android:onClick="loadPage"
android:tag="page1"
/>
My function should use this parameter to load the page1 activity.
public void loadPage(View view) {
String page = (String) view.getTag();
setContentView(R.layout.page);
}
How to make this work?
Tks

You want to specify in the button's tag the name of the layout, right?
Try the following:
String page = (String) view.getTag();
int layoutId= getResources().getIdentifier(page, "layout", getPackageName());
setContentView(layoutId);
Hope this helps.

You could use Java reflection API.
Each activity is an integer in R.layout. You only need to search for the attribute inside R.layout and then get its integer value to shove into setContentView.
try {
String tag = (String) btn.getTag(); // Button in variable "btn"
Class<R.layout> cls = R.layout.class;
Field field = cls.getDeclaredField(tag);
Integer obj = (Integer) field.get(null); // You could do these two in one line
int value = obj.intValue();
Log.i("Test", "Actvity id code = " + obj.toString()); // Testing code
setContentView(value);
}
catch (Exception e) {
e.printStackTrace();
return;
}