# App Optimisation, Testing & Deployment

### Check Memory Usage

- `abd shell dumpsys meminfo <package_name>`
    - Check if memory size increased since launch
    - Number of objects that have been created
    - Database information
- Terminology:
    - Native Heap: memory used by the process itself
    - Dalvik Heap: memory allocated by DalvikVM
    - Dalvik Other: memory used for JIT
    - Pss total: all connections to the main device memory thread
    - Private dirty: actual amount of RAM the app is using on the heap since the app started

### Code Optimisation

- Minimise object creation
- Make a method static if there is no need to modify the state of an object
- Make any constants `static final`
- `Int` is 2x faster than `float`
- Use enhanced for loops (for-each instead of regular for loops)

### App Testing

![image-20220118165511824](img/cc.png)

- Generally, developing tests is done before developing code

#### Unit Tests

- Build unit tests to verify the logic of specific code in the app
- Local tests
    - run on the local Java VM
- Instrumented tests
    - run based on the Android dependencies
    - Can use `mockito` or `robolectric` to isolate a unit from its dependencies

#### UI Tests

- Test an entire sequence of events, user interface, end-to-end testing on emulators & devices

- Tools: `AndroidJUnitRunner` & `Espresso API` & UI Automator

- Modify `build.gradle`

    ```groovy
    dependencies{
        androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
    }
    ```

- Espresso records UI interactions and can use these to run a repeatable test automatically

#### Monkey (stress test)

- Runs on an emulator and generates pseudo-random streams of user events (clicks, touches, gestures and system-level events)

```sh
$ adb shell monkey [options] <event-count>
$ adb shell monkey -p your.package.name -v 500
```

#### APK Generation

- Use a good / unique *package name*
    - `[org/com].[company].[product].[component]`
- Build `->` Generate Signed APK

##### Shrink Code & Resources (Proguard)

```groovy
buildTypes {
    release {
        minifyEnable true
        shrinkResources true
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}
```

Can try `proguard-android-optimize.txt` for more code shrinking