As we have seen in previous recipes, the Android SDK provides a wide range of components. But what happens when you can't find a prebuilt component that fits your unique needs? You can always create your own!
In this recipe, we will walk through creating a custom component that derives from the View class, just like the built-in widgets. Here's a high-level overview:
- Create a new class that extends View.
- Create custom constructor(s).
- Override onMeasure(), as the default implementation returns a size of 100 x 100.
- Override onDraw(), as the default implementation draws nothing.
- Define custom methods and listeners (such as the onClick() event).
- Implement custom functionality.
Overriding onMeasure() and onDraw() is not strictly required, but the default behavior is likely not what you would want.