What is IP address?

<h1 style="font-family: arial, sans-serif;">What is IP address?</h1><div style="color: #444444; font-family: arial, sans-serif; font-size: 14px;">An IP address, or simply an "IP," is a unique address that identifies a device on the Internet or a local network. It allows a system to be recognized by other systems connected via the Internet protocol. There are two primary types of IP address formats used today — IPv4 and IPv6.</div>

What is IP address?

What is IP address? An IP address, or simply an "IP," is a unique address that identifies a device on the Internet or a local netw...

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Build TV apps

<b><i>Build TV apps</i></b><br /><b><i><br /></i></b><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixzbAPvdIVpekCYZmOlIXOFb1uSf2m1kT55Yxl14XPBtSMzU2dPS63M0H6gcTlsSnNF-PSOwCI2cC7tcZ5ClgARZVuE-n_c8tkJPlOxFJHVk2wOfkEyqRNbCrxUIaO14bAhLvpnIKgTGAQ/s1600/images+%25286%2529.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="225" data-original-width="225" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixzbAPvdIVpekCYZmOlIXOFb1uSf2m1kT55Yxl14XPBtSMzU2dPS63M0H6gcTlsSnNF-PSOwCI2cC7tcZ5ClgARZVuE-n_c8tkJPlOxFJHVk2wOfkEyqRNbCrxUIaO14bAhLvpnIKgTGAQ/s1600/images+%25286%2529.png" /></a></div><b><i><br /></i></b><b><i><br /></i></b><b><i><br /></i></b>Android offers a rich user experience that's optimized for apps running on large screen devices, such as high-definition televisions. Apps on TV offer new opportunities to delight your users from the comfort of their couch.<br /><br />TV apps use the same structure as those for phones and tablets. This approach means you can create new TV apps based on what you already know about building apps for Android, or extend your existing apps to also run on TV devices. However, the user interaction model for TV is substantially different from phone and tablet devices. In order to make your app successful on TV devices, you must design new layouts that can be easily understood from 10 feet away, and provide navigation that works with just a directional pad and a select button.<br /><br />This class describes how to start building apps for TV, including setting up your development environment, basic requirements for layouts and navigation, as well as guidance on how to handle hardware features that are not typically available on TV devices.<br /><br />Note: You are encouraged to use Android Studio for building TV apps, because it provides project setup, library inclusion, and packaging conveniences. This training assumes you are using Android Studio.

Build TV apps

Build TV apps Android offers a rich user experience that's optimized for apps running on large screen devices, such as high-definition t...

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Build TV apps

<b><i>Build TV apps</i></b><br /><b><i><br /></i></b><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixzbAPvdIVpekCYZmOlIXOFb1uSf2m1kT55Yxl14XPBtSMzU2dPS63M0H6gcTlsSnNF-PSOwCI2cC7tcZ5ClgARZVuE-n_c8tkJPlOxFJHVk2wOfkEyqRNbCrxUIaO14bAhLvpnIKgTGAQ/s1600/images+%25286%2529.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="225" data-original-width="225" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEixzbAPvdIVpekCYZmOlIXOFb1uSf2m1kT55Yxl14XPBtSMzU2dPS63M0H6gcTlsSnNF-PSOwCI2cC7tcZ5ClgARZVuE-n_c8tkJPlOxFJHVk2wOfkEyqRNbCrxUIaO14bAhLvpnIKgTGAQ/s1600/images+%25286%2529.png" /></a></div><b><i><br /></i></b><b><i><br /></i></b><b><i><br /></i></b>Android offers a rich user experience that's optimized for apps running on large screen devices, such as high-definition televisions. Apps on TV offer new opportunities to delight your users from the comfort of their couch.<br /><br />TV apps use the same structure as those for phones and tablets. This approach means you can create new TV apps based on what you already know about building apps for Android, or extend your existing apps to also run on TV devices. However, the user interaction model for TV is substantially different from phone and tablet devices. In order to make your app successful on TV devices, you must design new layouts that can be easily understood from 10 feet away, and provide navigation that works with just a directional pad and a select button.<br /><br />This class describes how to start building apps for TV, including setting up your development environment, basic requirements for layouts and navigation, as well as guidance on how to handle hardware features that are not typically available on TV devices.<br /><br />Note: You are encouraged to use Android Studio for building TV apps, because it provides project setup, library inclusion, and packaging conveniences. This training assumes you are using Android Studio.

Build TV apps

Build TV apps Android offers a rich user experience that's optimized for apps running on large screen devices, such as high-definition t...

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Intents and Intent Filters

<b><i>Intents and Intent Filters</i></b><br /><br /><br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF2Dk3r7i1kBe52hvBFW9TpgJ_-x3uYdjk6xuqjVikUlXqhR8Gf2lUZ07YFKO_dlSQtjQWQzxBpEjO3rzWyAcUFFg1rwkrTQVbpK-xcpHBHZaM35B8PhmNtql48qLKOakJAJ43QaqAGoZP/s1600/intent-filters_2x.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="396" data-original-width="858" height="147" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF2Dk3r7i1kBe52hvBFW9TpgJ_-x3uYdjk6xuqjVikUlXqhR8Gf2lUZ07YFKO_dlSQtjQWQzxBpEjO3rzWyAcUFFg1rwkrTQVbpK-xcpHBHZaM35B8PhmNtql48qLKOakJAJ43QaqAGoZP/s320/intent-filters_2x.png" width="320" /></a></div><br />An Intent is a messaging object you can use to request an action from another app component. Although intents facilitate communication between components in several ways, there are three fundamental use cases:<br /><br />Starting an activity<br />An Activity represents a single screen in an app. You can start a new instance of an Activity by passing an Intent to startActivity(). The Intent describes the activity to start and carries any necessary data.<br /><br />If you want to receive a result from the activity when it finishes, call startActivityForResult(). Your activity receives the result as a separate Intent object in your activity's onActivityResult() callback. For more information, see the Activities guide.<br /><br />Starting a service<br />A Service is a component that performs operations in the background without a user interface. With Android 5.0 (API level 21) and later, you can start a service with JobScheduler. For more information about JobScheduler, see its API-reference documentation.<br /><br />For versions earlier than Android 5.0 (API level 21), you can start a service by using methods of the Service class. You can start a service to perform a one-time operation (such as downloading a file) by passing an Intent to startService(). The Intent describes the service to start and carries any necessary data.<br /><br />If the service is designed with a client-server interface, you can bind to the service from another component by passing an Intent to bindService(). For more information, see the Services guide.<br /><br />Delivering a broadcast<br />A broadcast is a message that any app can receive. The system delivers various broadcasts for system events, such as when the system boots up or the device starts charging. You can deliver a broadcast to other apps by passing an Intent to sendBroadcast() or sendOrderedBroadcast().<br /><br />The rest of this page explains how intents work and how to use them. For related information, see Interacting with Other Apps and Sharing Content.

Intents and Intent Filters

Intents and Intent Filters An Intent is a messaging object you can use to request an action from another app component. Although intents fac...

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Intents and Intent Filters

<b><i>Intents and Intent Filters</i></b><br /><br /><br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF2Dk3r7i1kBe52hvBFW9TpgJ_-x3uYdjk6xuqjVikUlXqhR8Gf2lUZ07YFKO_dlSQtjQWQzxBpEjO3rzWyAcUFFg1rwkrTQVbpK-xcpHBHZaM35B8PhmNtql48qLKOakJAJ43QaqAGoZP/s1600/intent-filters_2x.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="396" data-original-width="858" height="147" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF2Dk3r7i1kBe52hvBFW9TpgJ_-x3uYdjk6xuqjVikUlXqhR8Gf2lUZ07YFKO_dlSQtjQWQzxBpEjO3rzWyAcUFFg1rwkrTQVbpK-xcpHBHZaM35B8PhmNtql48qLKOakJAJ43QaqAGoZP/s320/intent-filters_2x.png" width="320" /></a></div><br />An Intent is a messaging object you can use to request an action from another app component. Although intents facilitate communication between components in several ways, there are three fundamental use cases:<br /><br />Starting an activity<br />An Activity represents a single screen in an app. You can start a new instance of an Activity by passing an Intent to startActivity(). The Intent describes the activity to start and carries any necessary data.<br /><br />If you want to receive a result from the activity when it finishes, call startActivityForResult(). Your activity receives the result as a separate Intent object in your activity's onActivityResult() callback. For more information, see the Activities guide.<br /><br />Starting a service<br />A Service is a component that performs operations in the background without a user interface. With Android 5.0 (API level 21) and later, you can start a service with JobScheduler. For more information about JobScheduler, see its API-reference documentation.<br /><br />For versions earlier than Android 5.0 (API level 21), you can start a service by using methods of the Service class. You can start a service to perform a one-time operation (such as downloading a file) by passing an Intent to startService(). The Intent describes the service to start and carries any necessary data.<br /><br />If the service is designed with a client-server interface, you can bind to the service from another component by passing an Intent to bindService(). For more information, see the Services guide.<br /><br />Delivering a broadcast<br />A broadcast is a message that any app can receive. The system delivers various broadcasts for system events, such as when the system boots up or the device starts charging. You can deliver a broadcast to other apps by passing an Intent to sendBroadcast() or sendOrderedBroadcast().<br /><br />The rest of this page explains how intents work and how to use them. For related information, see Interacting with Other Apps and Sharing Content.

Intents and Intent Filters

Intents and Intent Filters An Intent is a messaging object you can use to request an action from another app component. Although intents fac...

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Animations Overview

<b><i>Animations Overview</i></b><br /><b><i><br /></i></b><b><i><br /></i></b><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgw_FO4TcJJ0WcFvrxgUt6T2kA67PuHYPE2F4JtfDYiagHdaj1KtnutiL2_Q09UVbMR2Si0sTXG7fYVolC2ik8yVEhg_jbmttbWmuIxgkYrCaoN47pwLNDs3OnDOFivDZJfApYOypvJlLvF/s1600/targetchange_pba.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="957" data-original-width="600" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgw_FO4TcJJ0WcFvrxgUt6T2kA67PuHYPE2F4JtfDYiagHdaj1KtnutiL2_Q09UVbMR2Si0sTXG7fYVolC2ik8yVEhg_jbmttbWmuIxgkYrCaoN47pwLNDs3OnDOFivDZJfApYOypvJlLvF/s320/targetchange_pba.gif" width="200" /></a></div><b><i><br /></i></b>Animations can add visual cues that notify users about what's going on in your app. They are especially useful when the UI changes state, such as when new content loads or new actions become available. Animations also add a polished look to your app, which gives it a higher quality look and feel.<br /><br />Android includes different animation APIs depending on what type of animation you want, so this page provides an overview of the different ways you can add motion to your UI.<br /><br />To better understand when you should use animations, also see the material design guide to motion.<br /><br />Animate bitmaps<br /><br />Figure 1. An animated drawable<br /><br />When you want to animate a bitmap graphic such as an icon or illustration, you should use the drawable animation APIs. Usually, these animations are defined statically with a drawable resource, but you can also define the animation behavior at runtime.<br /><br />For example, animating a play button transforming into a pause button when tapped is a nice way to communicate to the user that the two actions are related, and that pressing one makes the other visible.<br /><br />For more information, read Animate Drawable Graphics.

Animations Overview

Animations Overview Animations can add visual cues that notify users about what's going on in your app. They are especially useful when ...

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Animations Overview

<b><i>Animations Overview</i></b><br /><b><i><br /></i></b><b><i><br /></i></b><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgw_FO4TcJJ0WcFvrxgUt6T2kA67PuHYPE2F4JtfDYiagHdaj1KtnutiL2_Q09UVbMR2Si0sTXG7fYVolC2ik8yVEhg_jbmttbWmuIxgkYrCaoN47pwLNDs3OnDOFivDZJfApYOypvJlLvF/s1600/targetchange_pba.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="957" data-original-width="600" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgw_FO4TcJJ0WcFvrxgUt6T2kA67PuHYPE2F4JtfDYiagHdaj1KtnutiL2_Q09UVbMR2Si0sTXG7fYVolC2ik8yVEhg_jbmttbWmuIxgkYrCaoN47pwLNDs3OnDOFivDZJfApYOypvJlLvF/s320/targetchange_pba.gif" width="200" /></a></div><b><i><br /></i></b>Animations can add visual cues that notify users about what's going on in your app. They are especially useful when the UI changes state, such as when new content loads or new actions become available. Animations also add a polished look to your app, which gives it a higher quality look and feel.<br /><br />Android includes different animation APIs depending on what type of animation you want, so this page provides an overview of the different ways you can add motion to your UI.<br /><br />To better understand when you should use animations, also see the material design guide to motion.<br /><br />Animate bitmaps<br /><br />Figure 1. An animated drawable<br /><br />When you want to animate a bitmap graphic such as an icon or illustration, you should use the drawable animation APIs. Usually, these animations are defined statically with a drawable resource, but you can also define the animation behavior at runtime.<br /><br />For example, animating a play button transforming into a pause button when tapped is a nice way to communicate to the user that the two actions are related, and that pressing one makes the other visible.<br /><br />For more information, read Animate Drawable Graphics.

Animations Overview

Animations Overview Animations can add visual cues that notify users about what's going on in your app. They are especially useful when ...

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Guide to background processing

<b><i>Guide to background processing</i></b><br /><b><i>  </i></b><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9-GHopdft3Dz8UPjetBWu8ho3QeqH8qXJBj0wRIOg8mAnIVcHZjWU-UMClmig-HyzpANPrB3YSYdmTgCQ_eAfFZ2VCyTMNTuAcOipC8zWejxjcDl6MkhO07Wv4wdJx8bI8bAC6aCazkqH/s1600/images+%25287%2529.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="183" data-original-width="275" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9-GHopdft3Dz8UPjetBWu8ho3QeqH8qXJBj0wRIOg8mAnIVcHZjWU-UMClmig-HyzpANPrB3YSYdmTgCQ_eAfFZ2VCyTMNTuAcOipC8zWejxjcDl6MkhO07Wv4wdJx8bI8bAC6aCazkqH/s1600/images+%25287%2529.jpeg" /></a></div><b><i><br /></i></b><b><i><br /></i></b><b><i><br /></i></b>Every Android app has a main thread which is in charge of handling UI (including measuring and drawing views), coordinating user interactions, and receiving lifecycle events. If there is too much work happening on this thread, the app appears to hang or slow down, leading to an undesirable user experience. Any long-running computations and operations such as decoding a bitmap, accessing the disk, or performing network requests should be done on a separate background thread. In general, anything that takes more than a few milliseconds should be delegated to a background thread. Some of these tasks may be required to be performed while the user is actively interacting with the app. To learn how you can run tasks on background threads and off the main UI thread while the app is actively being used, please take a look at the threading solutions guide.<br /><br />Applications may also require some tasks to run even when the user is not actively using the app such as syncing periodically with a backend server or fetching new content within an app on a periodic basis. Applications may also require services to run immediately to completion even after the user has completed interacting with the app. This guide will help you learn which solution best meets your needs for these use cases.<br /><br />Challenges in background processing<br />Background tasks consume a device's limited resources, like RAM and battery. This may result in a poor experience for the user if not handled correctly.<br /><br />In order to maximize battery and enforce good app behavior, Android restricts background work when the app (or a foreground service notification) is not visible to the user.<br /><br />Android 6.0 (API level 23) introduced Doze mode and app standby. Doze mode restricts app behavior when the screen is off and the device is stationary. App standby puts unused applications into a special state that restricts their network access, jobs, and syncs.<br />Android 7.0 (API level 24) limited implicit broadcasts and introduced Doze-on-the-Go.<br />Android 8.0 (API level 26) further limited background behavior, such as getting location in the background and releasing cached wakelocks.<br />Android 9 (API level 28) introduced App Standby Buckets, in which app requests for resources are dynamically prioritized based on app usage patterns.<br />It is important to understand your task needs and choose the right solution adhering to system best practices in scheduling your background job.

Guide to background processing

Guide to background processing    Every Android app has a main thread which is in charge of handling UI (including measuring and drawing vie...

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Guide to background processing

<b><i>Guide to background processing</i></b><br /><b><i>  </i></b><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9-GHopdft3Dz8UPjetBWu8ho3QeqH8qXJBj0wRIOg8mAnIVcHZjWU-UMClmig-HyzpANPrB3YSYdmTgCQ_eAfFZ2VCyTMNTuAcOipC8zWejxjcDl6MkhO07Wv4wdJx8bI8bAC6aCazkqH/s1600/images+%25287%2529.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="183" data-original-width="275" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9-GHopdft3Dz8UPjetBWu8ho3QeqH8qXJBj0wRIOg8mAnIVcHZjWU-UMClmig-HyzpANPrB3YSYdmTgCQ_eAfFZ2VCyTMNTuAcOipC8zWejxjcDl6MkhO07Wv4wdJx8bI8bAC6aCazkqH/s1600/images+%25287%2529.jpeg" /></a></div><b><i><br /></i></b><b><i><br /></i></b><b><i><br /></i></b>Every Android app has a main thread which is in charge of handling UI (including measuring and drawing views), coordinating user interactions, and receiving lifecycle events. If there is too much work happening on this thread, the app appears to hang or slow down, leading to an undesirable user experience. Any long-running computations and operations such as decoding a bitmap, accessing the disk, or performing network requests should be done on a separate background thread. In general, anything that takes more than a few milliseconds should be delegated to a background thread. Some of these tasks may be required to be performed while the user is actively interacting with the app. To learn how you can run tasks on background threads and off the main UI thread while the app is actively being used, please take a look at the threading solutions guide.<br /><br />Applications may also require some tasks to run even when the user is not actively using the app such as syncing periodically with a backend server or fetching new content within an app on a periodic basis. Applications may also require services to run immediately to completion even after the user has completed interacting with the app. This guide will help you learn which solution best meets your needs for these use cases.<br /><br />Challenges in background processing<br />Background tasks consume a device's limited resources, like RAM and battery. This may result in a poor experience for the user if not handled correctly.<br /><br />In order to maximize battery and enforce good app behavior, Android restricts background work when the app (or a foreground service notification) is not visible to the user.<br /><br />Android 6.0 (API level 23) introduced Doze mode and app standby. Doze mode restricts app behavior when the screen is off and the device is stationary. App standby puts unused applications into a special state that restricts their network access, jobs, and syncs.<br />Android 7.0 (API level 24) limited implicit broadcasts and introduced Doze-on-the-Go.<br />Android 8.0 (API level 26) further limited background behavior, such as getting location in the background and releasing cached wakelocks.<br />Android 9 (API level 28) introduced App Standby Buckets, in which app requests for resources are dynamically prioritized based on app usage patterns.<br />It is important to understand your task needs and choose the right solution adhering to system best practices in scheduling your background job.

Guide to background processing

Guide to background processing    Every Android app has a main thread which is in charge of handling UI (including measuring and drawing vie...

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Take photos

<b><i>Take photos </i></b><br /><b><i><br /></i></b><b><i><br /></i></b>Android Developers<br /><br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYHLaaK_I49rap0mVIJGtIrlY9NZSi8a8tvV11aYyt82EJR7EWjq40E9pIBIjchwbI4OwolEMP2nv7Nvhk9gGCh1QimeW3X3qxpsOdFhRo-YAWpdpqZDQKkLWlb75ovTbxNS1FUKc5T9eG/s1600/images+%25285%2529.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="207" data-original-width="245" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYHLaaK_I49rap0mVIJGtIrlY9NZSi8a8tvV11aYyt82EJR7EWjq40E9pIBIjchwbI4OwolEMP2nv7Nvhk9gGCh1QimeW3X3qxpsOdFhRo-YAWpdpqZDQKkLWlb75ovTbxNS1FUKc5T9eG/s1600/images+%25285%2529.png" /></a></div><br /><br />This lesson teaches how to capture a photo by delegating the work to another camera app on the device. (If you'd rather build your own camera functionality, see Controlling the Camera.)<br /><br />Suppose you are implementing a crowd-sourced weather service that makes a global weather map by blending together pictures of the sky taken by devices running your client app. Integrating photos is only a small part of your application. You want to take photos with minimal fuss, not reinvent the camera. Happily, most Android-powered devices already have at least one camera application installed. In this lesson, you learn how to make it take a picture for you.<br /><br />Request the camera feature<br />If an essential function of your application is taking pictures, then restrict its visibility on Google Play to devices that have a camera. To advertise that your application depends on having a camera, put a <uses-feature> tag in your manifest file:<br /><br /><manifest ... ><br />    <uses-feature android:name="android.hardware.camera"<br />                  android:required="true" /><br />    ...<br /></manifest><br /><br />If your application uses, but does not require a camera in order to function, instead set android:required to false. In doing so, Google Play will allow devices without a camera to download your application. It's then your responsibility to check for the availability of the camera at runtime by calling hasSystemFeature(PackageManager.FEATURE_CAMERA_ANY). If a camera is not available, you should then disable your camera features.

Take photos

Take photos  Android Developers This lesson teaches how to capture a photo by delegating the work to another camera app on the device. (If y...

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Take photos

<b><i>Take photos </i></b><br /><b><i><br /></i></b><b><i><br /></i></b>Android Developers<br /><br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYHLaaK_I49rap0mVIJGtIrlY9NZSi8a8tvV11aYyt82EJR7EWjq40E9pIBIjchwbI4OwolEMP2nv7Nvhk9gGCh1QimeW3X3qxpsOdFhRo-YAWpdpqZDQKkLWlb75ovTbxNS1FUKc5T9eG/s1600/images+%25285%2529.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="207" data-original-width="245" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYHLaaK_I49rap0mVIJGtIrlY9NZSi8a8tvV11aYyt82EJR7EWjq40E9pIBIjchwbI4OwolEMP2nv7Nvhk9gGCh1QimeW3X3qxpsOdFhRo-YAWpdpqZDQKkLWlb75ovTbxNS1FUKc5T9eG/s1600/images+%25285%2529.png" /></a></div><br /><br />This lesson teaches how to capture a photo by delegating the work to another camera app on the device. (If you'd rather build your own camera functionality, see Controlling the Camera.)<br /><br />Suppose you are implementing a crowd-sourced weather service that makes a global weather map by blending together pictures of the sky taken by devices running your client app. Integrating photos is only a small part of your application. You want to take photos with minimal fuss, not reinvent the camera. Happily, most Android-powered devices already have at least one camera application installed. In this lesson, you learn how to make it take a picture for you.<br /><br />Request the camera feature<br />If an essential function of your application is taking pictures, then restrict its visibility on Google Play to devices that have a camera. To advertise that your application depends on having a camera, put a <uses-feature> tag in your manifest file:<br /><br /><manifest ... ><br />    <uses-feature android:name="android.hardware.camera"<br />                  android:required="true" /><br />    ...<br /></manifest><br /><br />If your application uses, but does not require a camera in order to function, instead set android:required to false. In doing so, Google Play will allow devices without a camera to download your application. It's then your responsibility to check for the availability of the camera at runtime by calling hasSystemFeature(PackageManager.FEATURE_CAMERA_ANY). If a camera is not available, you should then disable your camera features.

Take photos

Take photos  Android Developers This lesson teaches how to capture a photo by delegating the work to another camera app on the device. (If y...

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Application Fundamentals developer

<b><i>Application Fundamentals developer.</i></b><br /><b><i><br /></i></b><b><i><br /></i></b><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjCtP6_Kf48RdCZXL9k7LVwZs5iBS7VCHpOIcsW3qo3vDOxLwcLd5DuRe_6-PLXIyxs7Uvj6fVk9cAB8yByVjvcPY2XR_fhyphenhyphencNW2xv6XFwVd0yBjKuFDyD-12Ti68JvEw1m1L3HAIPCMnoZ/s1600/images+%25286%2529.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="250" data-original-width="202" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjCtP6_Kf48RdCZXL9k7LVwZs5iBS7VCHpOIcsW3qo3vDOxLwcLd5DuRe_6-PLXIyxs7Uvj6fVk9cAB8yByVjvcPY2XR_fhyphenhyphencNW2xv6XFwVd0yBjKuFDyD-12Ti68JvEw1m1L3HAIPCMnoZ/s1600/images+%25286%2529.jpeg" /></a></div><br /><br />Android apps can be written using Kotlin, Java, and C++ languages. The Android SDK tools compile your code along with any data and resource files into an APK, an Android package, which is an archive file with an .apk suffix. One APK file contains all the contents of an Android app and is the file that Android-powered devices use to install the app.<br /><br />Each Android app lives in its own security sandbox, protected by the following Android security features:<br /><br />The Android operating system is a multi-user Linux system in which each app is a different user.<br />By default, the system assigns each app a unique Linux user ID (the ID is used only by the system and is unknown to the app). The system sets permissions for all the files in an app so that only the user ID assigned to that app can access them.<br />Each process has its own virtual machine (VM), so an app's code runs in isolation from other apps.<br />By default, every app runs in its own Linux process. The Android system starts the process when any of the app's components need to be executed, and then shuts down the process when it's no longer needed or when the system must recover memory for other apps.<br />The Android system implements the principle of least privilege. That is, each app, by default, has access only to the components that it requires to do its work and no more. This creates a very secure environment in which an app cannot access parts of the system for which it is not given permission. However, there are ways for an app to share data with other apps and for an app to access system services:<br /><br />It's possible to arrange for two apps to share the same Linux user ID, in which case they are able to access each other's files. To conserve system resources, apps with the same user ID can also arrange to run in the same Linux process and share the same VM. The apps must also be signed with the same certificate.<br />An app can request permission to access device data such as the user's contacts, SMS messages, the mountable storage (SD card), camera, and Bluetooth. The user has to explicitly grant these permissions. For more information, see Working with System Permissions.<br />The rest of this document introduces the following concepts:<br /><br />The core framework components that define your app.<br />The manifest file in which you declare the components and the required device features for your app.<br />Resources that are separate from the app code and that allow your app to gracefully optimize its behavior for a variety of device configurations.

Application Fundamentals developer

Application Fundamentals developer. Android apps can be written using Kotlin, Java, and C++ languages. The Android SDK tools compile your co...

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Application Fundamentals developer

<b><i>Application Fundamentals developer.</i></b><br /><b><i><br /></i></b><b><i><br /></i></b><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjCtP6_Kf48RdCZXL9k7LVwZs5iBS7VCHpOIcsW3qo3vDOxLwcLd5DuRe_6-PLXIyxs7Uvj6fVk9cAB8yByVjvcPY2XR_fhyphenhyphencNW2xv6XFwVd0yBjKuFDyD-12Ti68JvEw1m1L3HAIPCMnoZ/s1600/images+%25286%2529.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="250" data-original-width="202" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjCtP6_Kf48RdCZXL9k7LVwZs5iBS7VCHpOIcsW3qo3vDOxLwcLd5DuRe_6-PLXIyxs7Uvj6fVk9cAB8yByVjvcPY2XR_fhyphenhyphencNW2xv6XFwVd0yBjKuFDyD-12Ti68JvEw1m1L3HAIPCMnoZ/s1600/images+%25286%2529.jpeg" /></a></div><br /><br />Android apps can be written using Kotlin, Java, and C++ languages. The Android SDK tools compile your code along with any data and resource files into an APK, an Android package, which is an archive file with an .apk suffix. One APK file contains all the contents of an Android app and is the file that Android-powered devices use to install the app.<br /><br />Each Android app lives in its own security sandbox, protected by the following Android security features:<br /><br />The Android operating system is a multi-user Linux system in which each app is a different user.<br />By default, the system assigns each app a unique Linux user ID (the ID is used only by the system and is unknown to the app). The system sets permissions for all the files in an app so that only the user ID assigned to that app can access them.<br />Each process has its own virtual machine (VM), so an app's code runs in isolation from other apps.<br />By default, every app runs in its own Linux process. The Android system starts the process when any of the app's components need to be executed, and then shuts down the process when it's no longer needed or when the system must recover memory for other apps.<br />The Android system implements the principle of least privilege. That is, each app, by default, has access only to the components that it requires to do its work and no more. This creates a very secure environment in which an app cannot access parts of the system for which it is not given permission. However, there are ways for an app to share data with other apps and for an app to access system services:<br /><br />It's possible to arrange for two apps to share the same Linux user ID, in which case they are able to access each other's files. To conserve system resources, apps with the same user ID can also arrange to run in the same Linux process and share the same VM. The apps must also be signed with the same certificate.<br />An app can request permission to access device data such as the user's contacts, SMS messages, the mountable storage (SD card), camera, and Bluetooth. The user has to explicitly grant these permissions. For more information, see Working with System Permissions.<br />The rest of this document introduces the following concepts:<br /><br />The core framework components that define your app.<br />The manifest file in which you declare the components and the required device features for your app.<br />Resources that are separate from the app code and that allow your app to gracefully optimize its behavior for a variety of device configurations.

Application Fundamentals developer

Application Fundamentals developer. Android apps can be written using Kotlin, Java, and C++ languages. The Android SDK tools compile your co...

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Android developer guides

<b><i>Android developer guides</i></b><br /><b><i><br /></i></b><b><i><br /></i></b><div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMjYH3If0pFpEbmTHoqk6FKApdFPYVP3rrjHttlxutQcR_F4TnmJG4JaW6El2-RUcaLXP4J7ty-aCGhQa8Ng71a_9Updqrsl7Yl6z5T1mI9Vym8MkYVHr9ame5WTWIoz5k_hZXBXE0hHlz/s1600/Android-Developer-logo3.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="175" data-original-width="400" height="140" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMjYH3If0pFpEbmTHoqk6FKApdFPYVP3rrjHttlxutQcR_F4TnmJG4JaW6El2-RUcaLXP4J7ty-aCGhQa8Ng71a_9Updqrsl7Yl6z5T1mI9Vym8MkYVHr9ame5WTWIoz5k_hZXBXE0hHlz/s320/Android-Developer-logo3.png" width="320" /></a></div><br /><br /><br /></div><div>Welcome to the Android developer guides. The documents listed in the left navigation teach you how to build Android apps using APIs in the Android framework and other libraries.</div><div><br /></div><div>If you're brand new to Android and want to jump into code, start with the Build Your First App tutorial.</div><div><br /></div><div>And check out these other resources to learn Android development:</div><div><br /></div><div>Codelabs: Short, self-paced tutorials that each cover a discrete topic. Most codelabs step you through the process of building a small app, or adding a new feature to an existing app.</div><div>Courses: Guided training paths that teach you how to build Android apps.</div><div>Online training: If you prefer to learn online with videos, check out the Developing Android Apps course on Udacity (trailer embedded here), and other online courses below.</div><div>Otherwise, the following is a small selection of essential developer guides that you should be familiar with<b style="font-style: italic;">.</b></div>

Android developer guides

Android developer guides Welcome to the Android developer guides. The documents listed in the left navigation teach you how to build Android...

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Android developer guides

<b><i>Android developer guides</i></b><br /><b><i><br /></i></b><b><i><br /></i></b><div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMjYH3If0pFpEbmTHoqk6FKApdFPYVP3rrjHttlxutQcR_F4TnmJG4JaW6El2-RUcaLXP4J7ty-aCGhQa8Ng71a_9Updqrsl7Yl6z5T1mI9Vym8MkYVHr9ame5WTWIoz5k_hZXBXE0hHlz/s1600/Android-Developer-logo3.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="175" data-original-width="400" height="140" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMjYH3If0pFpEbmTHoqk6FKApdFPYVP3rrjHttlxutQcR_F4TnmJG4JaW6El2-RUcaLXP4J7ty-aCGhQa8Ng71a_9Updqrsl7Yl6z5T1mI9Vym8MkYVHr9ame5WTWIoz5k_hZXBXE0hHlz/s320/Android-Developer-logo3.png" width="320" /></a></div><br /><br /><br /></div><div>Welcome to the Android developer guides. The documents listed in the left navigation teach you how to build Android apps using APIs in the Android framework and other libraries.</div><div><br /></div><div>If you're brand new to Android and want to jump into code, start with the Build Your First App tutorial.</div><div><br /></div><div>And check out these other resources to learn Android development:</div><div><br /></div><div>Codelabs: Short, self-paced tutorials that each cover a discrete topic. Most codelabs step you through the process of building a small app, or adding a new feature to an existing app.</div><div>Courses: Guided training paths that teach you how to build Android apps.</div><div>Online training: If you prefer to learn online with videos, check out the Developing Android Apps course on Udacity (trailer embedded here), and other online courses below.</div><div>Otherwise, the following is a small selection of essential developer guides that you should be familiar with<b style="font-style: italic;">.</b></div>

Android developer guides

Android developer guides Welcome to the Android developer guides. The documents listed in the left navigation teach you how to build Android...

Read more »