Android Knowledge Simple test questions

Last week went to an android exam, the front of the basic topic is very simple but can not answer up, read and did, understand the gap is still very big, the following to tidy up a few questions to remember, encourage each other!

Still feel, want to take a good look official document is the right path!

1. Three ways to parse XML from Android: Sax,dom,pull

This article is very good: parsing xml in Android

2. Android architecture, divided into four layers:

1) Linux kernel: A layer of isolation abstraction for hardware and other software stacks, providing security mechanisms, memory management, process management, network protocol stacks, drivers, and more.

2) The middleware layer, which is composed of function library and Android runtime, mainly provides some library of functions based on C + +. Android runtime, including core libraries and Dalvik virtual machines. The former provides functionality and Java language functions specific to the Android system, which implements thread management and underlying memory management based on the Linux kernel.

3) Application framework: Provides basic management function and component reuse set mechanism of Android platform.

4) Applications: Provides a range of core applications, including email clients, browsers, contacts, calendars, and more.

3. There are several forms of android:lanuchmode in Android, what are their specific meanings?

The Launchmode property of <activity> has four modes of loading:

"Standard" (default mode)

"Singletop"

"Singletask"

"SingleInstance"

The specific difference or learning New summary, it is not copy: Basic Summary of the second: activity of the four kinds of launchmode

4. What are the differences between intent and pendingintent, and what are the common usage scenarios for the latter?

Intent represents a purpose, the first parameter represents the class, and the second parameter represents the target class.

Pendingintent is a description of the intent.

The difference between pendingintent and intent: pendingintent is a description of the intent, we can give this description to other programs, other programs according to this description at a later time to do what you do. In other words, intent literally means the intention, that our purpose, we want to do things in activity, we can execute it immediately, pendingintent equivalent to intent executed the wrapper, we don't necessarily have to execute it immediately, we will wrap it Passed to other activity or application. At this point, get to pendingintent application can according to the inside of the intent to know the intention of the issuer, choose volley or continue to pass or execute.

Pendingintent is a intent that can be executed under certain conditions, and its advantage over intent is that it carries a context object so that he does not have to rely on an activity to exist.

explanations of specific points can be found in: an in-depth understanding of pendingintent in Android

5. Explain the Android single threading model?

In fact, not so concise introduction clear: Found two reference blog: Simple analysis of Android single-threaded model and Android Single-threaded model

 

Android Knowledge Simple test questions