What methods can be used to prevent memory leaks in applications?

Memory leaks in Android applications can be prevented by:

• Releasing resources: always close Cursor, InputStream, OutputStream, and other resources after use.
• Avoiding strong references to Context: do not store references to Activity or Context in static variables to prevent garbage collection issues.
• Using WeakReference: for objects that should not prevent garbage collection.
• Unregistering listeners and callbacks: when destroying Activity or Fragment, unregister all listeners to avoid holding references.
• Checking for cyclic references: especially with anonymous classes and lambdas.
• Using profilers: Android Profiler, LeakCanary for detecting and analyzing leaks.

Example of using WeakReference:

class MyClass(context: Context) {
    private val contextRef = WeakReference(context)

    fun doSomething() {
        val ctx = contextRef.get()
        ctx?.let {
            // work with context
        }
    }
}