Switching Activities in Android Studio: Android Programming

Create and launch a second Android activity. Covers Intent, startActivity(), finish(), and the activity stack.

For tutorial on creating a button, see https://www.youtube.com/watch?v=aE5f1tV5nU4

Initial setup:
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Have project with initial activity and button for Toast

Create new activity: SecondActivity
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Show .xml, .java, and manifest.

Launch activity:
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startActivity(new Intent( [Current Activity's 'this'], [New Activity's Java].class));

Encapsulate launching
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Intent i = SecondClass.makeIntent(this)
startActivity();

Activity Stack
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- Loading an Activity pushes it on the Activity *Stack*
- Pressing back button pops stack:
destroys this activity, returns to previous activity.
- New Button runs activity's finish() method pops it in code.
Must use correctly to have good activity stack.
If you instead startActivity() back to the first one, you make a loop.

Can move on and kill current activity:
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startActivity(...);
finish();

Troubleshooting:
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- Demonstrate what happens with the activity being in the manifest.
* View LogCat via DDMS:
...android.content.ActivityNotFoundException: Unable to find explicit activity class ...; have you declared this activity in your AndroidManifest.xml?