android developer profile summary

Android uses two general properties to classify device screens: size and pixel density. As a developer, we have to design our applications to take into account that our applications are installed on devices with different screen sizes and pixel densities. Therefore, our app should include an optional resource to optimize the application appearance to support devices of different sizes and pixel densities.Th

Because the current project needs to modify the Android kernel source code, so I need to start from the Android source code to learn from the compilation.Here's a look at my compilation environment.The version of the Ubuntu system I use is 14.04, 64 bit.GCC version: 4.8.8The compilation process I was looking at the Google Developer website, and the combination of

Serviceconnection, you should override the OnDestroy method, unbind, One of the principles of service is whether the first start or bind OnCreate method executes only once, in other words, no matter how many times you execute StartService or Bindservice service is created only once,Multiple calls to the StartService OnStart method are called more than once, and multiple calls to the Bindservice Onbind method are performed only once, and only once for multiple destroy. Multiple calls to Unbindse

Android interview question Summary (2)Preface I have been looking for a job for almost two weeks since I recently resigned. During this time, I have learned the difference and depth of my knowledge about the technical concepts of Beijing, Shanghai, Guangzhou, and Western cities. as the saying goes: I am ashamed and brave. After the interview was abused, I also found my professional qualities and development

It's going to be over this year, I've been transitioning from WPF to qt/qml this year, and I've been working on Android lately, and from my personal experience, whether it's QML or Android is similar to WPF in terms of framework and design, and the mobile side is designed for many reasons, Far from the desktop is delicate, complex, so if you master the idea of WPF and then engage in QML or

Configure the android environment in Ubuntu 1. JDK installation. I installed JDK 6. For details, see the JDK Installation Summary In ubuntu. 2. Download eclipse Download a Linux version of eclipse and run eclipse. Click Help> Software Updates> available software. Click the "add site..." button and enter the https://dl-ssl.google.com/android/eclipse/ in it and

components such as service and Broadcastreceiver, Packagemanager also provides a similar way to obtain component information that is successfully matched, such as queryintentservices, Querybroadcastreceivers and Other methodsOne type of action and category are important, and they are used together to indicate that this is an entry activity and that it will appear in the list of applications in the system.The composition of the 6.ActivityThe composition of the activity is not as simple as an Act

framelayout or when one layout contains another, the Merge tab eliminates the extra view groups in the view hierarchy.The Merge tab can be used in two typical cases:A. the top node of the layout is framelayout and does not need to set properties such as background or padding, which can be replaced with merge because the parent view of the activity content view is a framelayout. So you can use merge to eliminate only one left.B. when a layout is used as a sub-layout by another layout include, us

(LayoutParams . wrap_content)/////If you want to get the value of the actual layout size of the Popupwindow object, you can use the following code: View.measure (Layoutparams.wrap_content, layou Tparams.wrap_content); int viewwidth = View.getmeasuredwidth (); int viewheight = View.getmeasuredheight (); Pop.setwidth (Viewwidth); Pop.setheight (Viewheight); System.out.println ("Pop width =" +pop.getwidth ()); System.out.prin

efficient use of hardware acceleration switches:Reduce the number of views in your applicationAvoid OverdrawDon ' t create render objects in Draw methodsDon ' t modify shapes too oftenDon ' t modify bitmaps too oftenLater turned on the Android developer option to check whether the feature was over-drawn, it was found that the interface was obviously over-drawn. Here basically can be drawn, this interface d

Previous time to the previous app added share function, share some experience with you.There are three ways to share features:1. Call the Android to bring the sharing interface, this is the simplest way, it is directly call the app's hair information function, the link is sent through the information way, so it is less effective sharing. It can only be sent to social apps that are already installed on your phone. The pit is that some apps are shielded

Android interview Summary 11 handler message loop messageQueueProcessing2 fragment Lifecycle3 ContentProvider4 WebView5 BroadCastreciver Broadcast6. Obtain ContentProvider ContentReciver from the address bookObtains the user's profile picture and mobile phone number.7. Incorrect ListVIew ImageThink about it:GetView () Check the source code8 ListView optimization:

the engineering/res/layout. In Android, the developer defines the user interface in an XML document, allowing the XML document to be dedicated to the user UI interface design, while the Java program is responsible for the implementation of the function, which reduces the program coupling and facilitates the maintenance and expansion of the program.Most of the interface controls are in Android.view and andr

stack. While the startup mode of the component will affect its record in the task stack, the Android project manifest profile Androidmanifest.xmlConfigure the Android:launchmode property within the 2. When activity is activated at the top of the stack, the new object's stack top unique mode singletop is not created. 3. When the activity is not changed in the task stack, the activation will create a new obj

OverviewAs an Android developer, I'm afraid the context can rank the previous number in the most used classes of the day. Because context objects are so common in our projects, we are loading resources, starting activities, getting service, sending broadcast, and creating view with context involved. In short, context is an environment that provides a variety of functions, resources, and services for an

Android dynamic layout compared to static layout, dynamic layout does not change the XML layout code, improve the efficiency, of course, can be ignored. Dynamic layout is mainly flexible, you can quickly modify the layout of the code directly, and directly using the control for business logic development. However, the amount of code is usually relatively large, maintenance is not static layout convenience. However, as an

different task There is only one instance of Singletask activity Singletask activity If a separate Taskaffinity property value is set, it will be in a new task when it is started, or it will be in an existing task When the activity of Singletask is started, it will see whether the corresponding activity instance already exists in the target task (new task or existing task), and if so, The activity on the activity instance will be destroyed (pop, destroy), that is, the activity insta

(msecondaryconnection); }}4. If you need to pass object objects in the Aidl file, you need to add the corresponding. aidl file1 , define the object data, and implement Parcelable 2 , add the Data.aidl file, and write the import data in the following way 3 , you need to import com.aidl.Data in a. aidl file that references to Data. 4 , you need to add data.aidl and Data.java files on both the server side and the client and need to be consistent. Data.aidlaidl file: Package com.aidl;parcelable Dat

cross-compilation tool chainSecond, build the file system image production environment1. Create the root file system directory Rootfs and its subdirectories bin,sbin,boot,root,sys,srv,proc,usr, etc.2. Compile busybox1.7.0: (Required source Bundle: BUSYBOX-1.7.0.TAR.BZ2)2.1 Decompression Source Package, enter the source directory;2.2 Configuration BusyBox: Do make menuconfig in the source directory, if you use the default configuration to exit, save, if you need to configure your own then change

feedback 3. Each button has a pressed state of 4. When the interface has a return button, back will perform the same operation 5. If the picture requires a network pull, or no picture, is there a default picture instead of 6. Turn on developer options, tick show layout boundaries, check that the clickable range of each button is reasonableMulti-lingual:1. Language habits in other languages (e.g. traditional) 2. English note plural 3. In multiple lang