Android Intent

1. Use Explicit Intent to start another Activity
   From StartActivity.kt to start LocalMusicActivity.kt

val intent = Intent(this@StartActivity, LocalMusicActivity::class.java)
startActivity(intent)

• If this error happened in Logcat.

android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.simplemusic/com.example.simplemusic.activity.LocalMusicActivity}; have you declared this activity in your AndroidManifest.xml, or does your intent not match its declared ?

Remember to declare the activity in AndroidManifest.xml

<activity android:name="com.example.simplemusic.activity.LocalMusicActivity" />

1. Pass data with Intent using Bundle directly

val intent =
    Intent(this@StartActivity, LocalMusicActivity::class.java)
val bundle = Bundle()
bundle.putString("action", "play")
bundle.putInt("count", 10)
intent.putExtras(bundle)
startActivity(intent)

In the target Activity

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
  
    val bundle = this.intent.extras
    Log.d(
        "Intent data",
        "name: ${bundle?.getString("name")}, action: ${bundle?.getString("action")}, count: ${
            bundle?.getInt("count")
        }"
    )
// ...

Output

name: null, action: play, count: 10

1. Pass data with Intent

val intent =
    Intent(this@StartActivity, LocalMusicActivity::class.java)
intent.putExtra("action", "play")
intent.putExtra("count", 10)
startActivity(intent)

The same result as the last one. It will create a bundle auto.

public @NonNull Intent putExtra(String name, @Nullable String value) {
    if (mExtras == null) {
        mExtras = new Bundle();
    }
    mExtras.putString(name, value);
    return this;
}