How do I get the resource id of an image if I know its name in Android?

This example demonstrate about How do I get the resource id of an image if I know its name in Android

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.java

<? xml version= "1.0" encoding= "utf-8" ?>
<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
   xmlns: tools = "http://schemas.android.com/tools"
   android :id= "@+id/linearLayout"
   android :layout_width= "match_parent"
   android :layout_height= "match_parent"
   android :orientation= "vertical"
   tools :context= ".MainActivity" >
   <ImageView
      android :id= "@+id/ivLauncer"
      android :layout_width= "match_parent"
      android :layout_height= "450dp"
      android :contentDescription= "@string/app_name"
      android :src= "@drawable/ic_launcher_background" />
   <TextView
      android :id= "@+id/tvResourceId"
      android :layout_width= "match_parent"
      android :layout_height= "wrap_content" />
</LinearLayout>

Step 3 − Add the following code to src/MainActivity.java

package app.tutorialspoint.com.sample ;
import android.os.Bundle ;
import android.support.v7.app.AppCompatActivity ;
import android.util.Log ;
import android.widget.TextView ;
public class MainActivity extends AppCompatActivity {
   @Override
   protected void onCreate (Bundle savedInstanceState) {
      super .onCreate(savedInstanceState) ;
      setContentView(R.layout. activity_main ) ;
      String mDrawableName = "ic_launcher_background" ;
      int resID = getResources().getIdentifier(mDrawableName , "drawable" ,
      getPackageName()) ;
      TextView tvResourceId = findViewById(R.id. tvResourceId ) ;
      tvResourceId.setText(String. valueOf (resID)) ;
   }
}

Step 4 − Add the following code to androidManifest.xml

<? xml version= "1.0" encoding= "utf-8" ?>
<manifest xmlns: android = "http://schemas.android.com/apk/res/android"
   package= "app.tutorialspoint.com.sample" >
   <uses-permission android :name= "android.permission.VIBRATE" />
   <application
      android :allowBackup= "true"
      android :icon= "@mipmap/ic_launcher"
      android :label= "@string/app_name"
      android :roundIcon= "@mipmap/ic_launcher_round"
      android :supportsRtl= "true"
      android :theme= "@style/AppTheme" >
      <activity android :name= ".MainActivity" >
         <intent-filter>
            <action android :name= "android.intent.action.MAIN" />
            <category android :name= "android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen –