Simple android app sample hello world download

Android Training Android Tutorial. AppCompatActivity; import android. Reinforcement Learning. R Programming. React Native. Python Design Patterns. Python Pillow. Python Turtle. Verbal Ability. Interview Questions. Company Questions. A data cable to connect your Android device to your computer via the USB port. If you are using a Linux or Windows system, you may need to perform additional steps to run on a hardware device. Check the Using Hardware Devices documentation.

You may also need to install the appropriate USB driver for your device. Developer options appears in the list. Tap Developer options. Choose USB Debugging. Connect your device to your development machine with a USB cable. Click the Run button in the toolbar.

The Select Deployment Target window opens with the list of available emulators and connected devices. Select your device, and click OK.

Android Studio installs and runs the app on your device. Troubleshooting If your Android Studio does not recognize your device, try the following: Unplug and replug your device. Restart Android Studio. If your computer still does not find the device or declares it "unauthorized", follow these steps: Unplug the device. On the device, open Developer Options in Settings app. Reconnect the device to your computer. When prompted, grant authorizations. Task 5: Change the app Gradle configuration In this task you will change something about the app configuration in the build.

The content of the file appears in the code editor. Within the defaultConfig block, change the value of minSdkVersion to 17 as shown below it was originally set to The code editor shows a notification bar at the top with the Sync Now link. Task 6: Add log statements to your app In this task, you will add Log statements to your app, which display messages in the Logcat pane.

In the figure above: The Logcat tab for opening and closing the Logcat pane, which displays information about your app as it is running. If you add Log statements to your app, Log messages appear here. The Log level menu set to Verbose the default , which shows all Log messages.

Other settings include Debug , Error , Info , and Warn. For example: Log. Other log levels are e for Error , w for Warn , and i for Info. This is commonly the name of the Activity from which the message originates. However, you can make this anything that is useful to you for debugging. To add unambiguous imports automatically to your project such as android. Select all checkboxes and set Insert imports on paste to All.

Click Apply and then click OK. In the onCreate method of MainActivity , add the following statement: Log. Check that the name of the target and package name of the app are correct.

Change the Log level in the Logcat pane to Debug or leave as Verbose since there are so few log messages. Run your app. The following message should appear in the Logcat pane: Coding challenge Challenge: Now that you are set up and familiar with the basic development workflow, do the following: Create a new project in Android Studio.

Change the "Hello World" greeting to "Happy Birthday to " and the name of someone with a recent birthday. Optional Take a screenshot of your finished app and email it to someone whose birthday you forgot. A common use of the Log class is to log Java exceptions when they occur in your program. There are some useful methods, such as Log. Explore methods you can use to include an exception with a Log message. Then, write code in your app to trigger and log an exception.

Summary To install Android Studio, go to Android Studio and follow the instructions to download and install it. When creating a new app, ensure that API Android 4. To see the app's Android hierarchy in the Project pane, click the Project tab in the vertical tab column, and then choose Android in the popup menu at the top.

Edit the build. The java folder includes activities, tests, and other components in Java source code. Edit the AndroidManifest. All components for an app, such as multiple activities, must be declared in this XML file. Add Log statements to your app, which display messages in the Logcat pane as a basic tool for debugging. Return to the previous screen Settings , and tap Developer options. Related concepts The related concept documentation is in 1. Sharing files with NFC. Printing files.

Content providers. Autofill framework. Contacts provider. Data backup. Remember and authenticate users. User location. Using touch gestures.

Handling keyboard input. Supporting game controllers. Input method editors. Performing network operations. Transmit network data using Volley. Perform network operations using Cronet. Transferring data without draining the battery. Reduce network battery drain. Transfer data using Sync Adapters. Bluetooth Low Energy. Wi-Fi infrastructure.

Discover and connect. Runtime API reference. Web-based content. Android App Bundles. Google Play. Play Asset Delivery.

Play Feature Delivery. In-app reviews. In-app updates. Google Play Instant. Get started with instant apps. Get started with instant games. Integrate with Firebase. Play Install Referrer. Play Install Referrer Library. Application Licensing. Android GPU Inspector. System profiling. Analyze a system profile. GPU performance counters.

Frame profiling. Analyze a frame profile. Frame Profiler UI. Customize or port game engines. Process input events. Support game controllers. Achieve proper frame pacing. After entered application name, it going to be called select the form factors your application runs on, here need to specify Minimum SDK, in our tutorial, I have declared as API Android 6.

The next level of installation should contain selecting the activity to mobile, it specifies the default layout for Applications. This contains the. By default, it includes an MainActivity. This is a directory for other various XML files that contain a collection of resources, such as strings and colours definitions. This is the manifest file which describes the fundamental characteristics of the app and defines each of its components. The main activity code is a Java file MainActivity.

This is the actual application file which ultimately gets converted to a Dalvik executable and runs your application. Following is the default code generated by the application wizard for Hello World! Here, R.