Download What's new User guide Preview. Meet Android Studio. Manage your project. Write your app. Build and run your app. Run apps on the emulator. Run apps on a hardware device. Configure your build. Optimize your build speed. Debug your app. Test your app. Profile your app. Android Studio profilers. Profile CPU activity. Benchmark your app. Measure performance. Publish your app.
Command line tools. Android Developers. Enable developer options and USB debugging Figure 1. Developer options. Figure 2. Add to Quick Settings panel. Figure 3. Debugging options enabled. Figure 4. View attributes. Figure 5. Select USB Configuration. Figure 6. Haz clic en Crear proyecto nuevo.
Elige el proyecto que quieras vincular. Si tu proyecto no aparece en la lista, verifica lo siguiente: Tu cuenta de Google Play Console debe estar designada como propietaria. Haz clic en Vincular un proyecto existente. En Cuentas de servicio , haz clic en Crear una nueva cuenta de servicio.
Cuando termines, haz clic en Actualizar el consentimiento para OAuth. Your application is susceptible to being destroyed by the OS whenever it leaves the sight of the user. There are two main situations in which this can occur. The first and most obvious case is when the user presses the home button or switches to another application. However, there is a second and much more subtle case that certain plugins can introduce. As noted above, Cordova applications are usually confined to the single activity that contains the Webview.
However, there are instances in which other activities may be launched by plugins and temporarily push the Cordova activity to the background. These other Activities are typically launched in order to perform a specific task using a native application installed on the device. For example, the Cordova camera plugin launches whatever camera activity is natively installed on the device in order to take a photo.
Reusing the installed camera application in this way makes your application feel much more like a native app when the user tries to take a photo. Unfortunately, when the native Activity pushes your app to the background there is a chance the OS will kill it.
For a clearer understanding of this second case, let's walk through an example using the camera plugin. Imagine you have an application that requires the user to take a profile photo. The flow of events in the application when everything goes as planned will look something like this:. However, this flow of events can be disrupted if a device is low on memory. If the Activity is killed by the OS, the above sequence of events instead plays out as follows:.
In this instance, the OS killed the application in the background and the application did not maintain its state as part of the lifecycle. When the user returned to the app, the Webview was recreated and the app appeared to have restarted from scratch hence the user's confusion. This sequence of events is equivalent to what happens when the home button is pressed or the user switches applications.
The key to preventing the above experience is subscribing to events and properly maintaining state as part of the activity lifecycle. In the examples above, the javascript events that are fired are noted in italics.
These events are your opportunity to save and restore your application's state. You should register callbacks in your application's bindEvents function that respond to the lifecycle events by saving state. What information you save and how you save it is left to your discretion, but you should be sure to save enough information so that you can restore the user to exactly where they left off when they return to your application.
There is one additional factor in the example above that only applies in the second-discussed situation i. Not only was the state of the application lost when the user finished taking a photo, but so was the photo that the user took. Normally, that photo would be delivered to your application through the callback that was registered with the camera plugin.
However, when the Webview was destroyed that callback was lost forever. Luckily, cordova-android 5. When the OS destroys the Cordova activity that was pushed into the background by a plugin, any pending callbacks are lost as well. This means that if you passed a callback to the plugin that launched the new activity e. However, starting in cordova-android 5. The possible values for pluginStatus in the pendingResult field include the following:.
Please note that it is up to the plugin to decide what is contained in the result field and the meaning of the pluginStatus that is returned. Reference the API of the plugin you are using to see what you should expect those fields to contain and how to use their values. Below is a brief example application that uses the resume and pause events to manage state. It uses the Apache camera plugin as an example of how to retrieve the results of a plugin call from the resume event payload.
The portion of the code dealing with the resume 's event. On an Android 9 device, clear text communication is now disabled by default.
The key reason for avoiding cleartext traffic is the lack of confidentiality, authenticity, and protections against tampering; a network attacker can eavesdrop on transmitted data and also modify it without being detected. You can learn more about the android:usesCleartextTraffic or any other android application elements setting in the documentation for Android developers.
To allow clear text communication again, set the android:usesCleartextTraffic on your application tag to true in config. You can learn more about the Android manifest information in the documentation for Android developers.
Android provides a developer setting for testing Activity destruction on low memory. Enable the "Don't keep activities" setting in the Developer Options menu on your device or emulator to simulate low memory scenarios. You should always do some amount of testing with this setting enabled to make sure that your application is properly maintaining state.
Android Platform Guide This guide shows how to set up your SDK environment to deploy Cordova apps for Android devices, and how to optionally use Android-centered command-line tools in your development workflow. Setting environment variables Cordova's CLI tools require some environment variables to be set in order to function correctly.
This can be important if your project uses large native libraries, which can drastically increase the size of the generated APK.
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