com.dukescript.presenters

Class Android

java.lang.Object

android.content.Context

android.content.ContextWrapper

android.view.ContextThemeWrapper

android.app.Activity

com.dukescript.presenters.Android

All Implemented Interfaces:

ComponentCallbacks, ComponentCallbacks2, KeyEvent.Callback, LayoutInflater.Factory, LayoutInflater.Factory2, View.OnCreateContextMenuListener, Window.Callback

public final class Android
extends Activity

Ultimate DukeScript Presenter for all Android devices.

Use as a launching activity of your portable DukeScript application or configure any WebView in your (existing) Android application to give you easy access to HTML features (like charts, maps, canvas or more) from Java by using the configure(java.lang.String, android.webkit.WebView, java.lang.String, java.lang.Boolean) method.

To use this presenter specify following dependency:

 <dependency>
   <groupId>com.dukescript.presenters</groupId>
   <artifactId>android</artifactId>
   <version>1.7</version>
 </dependency>
 

Embedding

Read more about embedding DukeScript technology into existing Android application. Start at the configure method.

Cross-Platform

Learn how to build fully portable (iOS, browser, desktop) Java applications in DukeScript getting started tutorial. Details about configuring Android manifest file can be found in the activity definition section.

Nested Class Summary

Nested classes/interfaces inherited from class android.content.Context

Context.BindServiceFlags

Field Summary

Fields inherited from class android.app.Activity

DEFAULT_KEYS_DIALER, DEFAULT_KEYS_DISABLE, DEFAULT_KEYS_SEARCH_GLOBAL, DEFAULT_KEYS_SEARCH_LOCAL, DEFAULT_KEYS_SHORTCUT, FOCUSED_STATE_SET, RESULT_CANCELED, RESULT_FIRST_USER, RESULT_OK

Fields inherited from class android.content.Context

BIND_ABOVE_CLIENT, BIND_ADJUST_WITH_ACTIVITY, BIND_ALLOW_OOM_MANAGEMENT, BIND_AUTO_CREATE, BIND_DEBUG_UNBIND, BIND_FOREGROUND_SERVICE, BIND_FOREGROUND_SERVICE_WHILE_AWAKE, BIND_IMPORTANT, BIND_NOT_FOREGROUND, BIND_NOT_VISIBLE, BIND_SHOWING_UI, BIND_TREAT_LIKE_ACTIVITY, BIND_VISIBLE, BIND_WAIVE_PRIORITY, MODE_APPEND, MODE_ENABLE_WRITE_AHEAD_LOGGING, MODE_MULTI_PROCESS, MODE_PRIVATE, MODE_WORLD_READABLE, MODE_WORLD_WRITEABLE

Fields inherited from interface android.content.ComponentCallbacks2

TRIM_MEMORY_BACKGROUND, TRIM_MEMORY_COMPLETE, TRIM_MEMORY_MODERATE, TRIM_MEMORY_RUNNING_CRITICAL, TRIM_MEMORY_RUNNING_LOW, TRIM_MEMORY_RUNNING_MODERATE, TRIM_MEMORY_UI_HIDDEN

Constructor Summary

Constructors

Constructor and Description
Android()

Method Summary

Modifier and Type	Method and Description
static Executor	configure(String licenseKey, WebView view, String page, Boolean runOnUiThread) Configures an instance of WebView to give you easy access to HTML features from Java.
static Fn.Presenter	create(WebView view, String page) Deprecated. Consider using configure(java.lang.String, android.webkit.WebView, java.lang.String, java.lang.Boolean) which offers more control over behavior of Android DukeScript presenter.
void	onCreate(Bundle savedInstanceState) Initializes the Activity by creating a WebView and setting it up to allow execution of DukeScript application.

Methods inherited from class android.app.Activity

addContentView, closeContextMenu, closeOptionsMenu, createPendingResult, dismissDialog, dispatchGenericMotionEvent, dispatchKeyEvent, dispatchKeyShortcutEvent, dispatchPopulateAccessibilityEvent, dispatchTouchEvent, dispatchTrackballEvent, dump, findViewById, finish, finishActivity, finishActivityFromChild, finishAffinity, finishFromChild, getActionBar, getApplication, getCallingActivity, getCallingPackage, getChangingConfigurations, getComponentName, getCurrentFocus, getFragmentManager, getIntent, getLastNonConfigurationInstance, getLayoutInflater, getLoaderManager, getLocalClassName, getMenuInflater, getParent, getParentActivityIntent, getPreferences, getRequestedOrientation, getSystemService, getTaskId, getTitle, getTitleColor, getVolumeControlStream, getWindow, getWindowManager, hasWindowFocus, invalidateOptionsMenu, isChangingConfigurations, isChild, isFinishing, isTaskRoot, managedQuery, moveTaskToBack, navigateUpTo, navigateUpToFromChild, onActionModeFinished, onActionModeStarted, onActivityResult, onApplyThemeResource, onAttachedToWindow, onAttachFragment, onBackPressed, onChildTitleChanged, onConfigurationChanged, onContentChanged, onContextItemSelected, onContextMenuClosed, onCreateContextMenu, onCreateDescription, onCreateDialog, onCreateDialog, onCreateNavigateUpTaskStack, onCreateOptionsMenu, onCreatePanelMenu, onCreatePanelView, onCreateThumbnail, onCreateView, onCreateView, onDestroy, onDetachedFromWindow, onGenericMotionEvent, onKeyDown, onKeyLongPress, onKeyMultiple, onKeyShortcut, onKeyUp, onLowMemory, onMenuItemSelected, onMenuOpened, onNavigateUp, onNavigateUpFromChild, onNewIntent, onOptionsItemSelected, onOptionsMenuClosed, onPanelClosed, onPause, onPostCreate, onPostResume, onPrepareDialog, onPrepareDialog, onPrepareNavigateUpTaskStack, onPrepareOptionsMenu, onPreparePanel, onRestart, onRestoreInstanceState, onResume, onRetainNonConfigurationInstance, onSaveInstanceState, onSearchRequested, onStart, onStop, onTitleChanged, onTouchEvent, onTrackballEvent, onTrimMemory, onUserInteraction, onUserLeaveHint, onWindowAttributesChanged, onWindowFocusChanged, onWindowStartingActionMode, openContextMenu, openOptionsMenu, overridePendingTransition, recreate, registerForContextMenu, removeDialog, requestWindowFeature, runOnUiThread, setContentView, setContentView, setContentView, setDefaultKeyMode, setFeatureDrawable, setFeatureDrawableAlpha, setFeatureDrawableResource, setFeatureDrawableUri, setFinishOnTouchOutside, setIntent, setProgress, setProgressBarIndeterminate, setProgressBarIndeterminateVisibility, setProgressBarVisibility, setRequestedOrientation, setResult, setResult, setSecondaryProgress, setTitle, setTitle, setTitleColor, setVisible, setVolumeControlStream, shouldUpRecreateTask, showDialog, showDialog, startActionMode, startActivities, startActivities, startActivity, startActivity, startActivityForResult, startActivityForResult, startActivityFromChild, startActivityFromChild, startActivityFromFragment, startActivityFromFragment, startActivityIfNeeded, startActivityIfNeeded, startIntentSender, startIntentSender, startIntentSenderForResult, startIntentSenderForResult, startIntentSenderFromChild, startIntentSenderFromChild, startManagingCursor, startNextMatchingActivity, startNextMatchingActivity, startSearch, stopManagingCursor, takeKeyEvents, triggerSearch, unregisterForContextMenu

Methods inherited from class android.view.ContextThemeWrapper

attachBaseContext, getTheme, setTheme

Methods inherited from class android.content.ContextWrapper

getAssets, getBaseContext, getDatabasePath, getFilesDir, getPackageManager, getPackageName, getResources, openFileOutput

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Android

public Android()

Method Detail

configure

public static Executor configure(String licenseKey,
                                 WebView view,
                                 String page,
                                 Boolean runOnUiThread)

Configures an instance of WebView to give you easy access to HTML features from Java. Use this method to embed HTML components into your existing application. By configuring your WebView you can use all the DukeScript goodies like:

• charts
• maps
• canvas
• UI bindings

and still code in the same language that you use for the rest of your application - e.g. in Java or Kotlin.

Accessing the HTML Content

There can be multiple WebView components in your application and it is thus essential to always identify the one you are working with. As such the HTML content of your WebView needs to be accessed from a dedicated Executor provided to you as a return value of the configure method. Use Executor.execute(java.lang.Runnable) to switch into the context of the WebView and perform an action.

Here is an example to display an alert in your view and its associated executor created as a result of

 Executor executor = Android.configure(null, view, null, null);
 executor.execute(new Runnable {
     public void run() {
        alert("Hello World!");
     }
     @JavaScriptBody(args = { "msg" }, body = "alert(msg);")
     native void alert(String msg);
 });
 

The example is using JavaScriptBody annotation (you can read more about this building block of DukeScript system here), but in most cases you are likely to use one of the predefined Java wrappers. For example there are JQuery bindings which you may consider to use instead.

Threading

The HTML content of your WebView needs to be accessed from a single thread. The same thread is also making callbacks to your Java code. To post a task into such thread use the returned Executor's Executor.execute(java.lang.Runnable) method. Those are the basics.

Now the tougher part: the thread for accessing the HTML content can be the same as Android UI thread, but due to bug 438255 this reliably works only on Android SDK 24 and newer - otherwise it may cause deadlocks.

To control whether the Android UI thread is the one to make calls into your WebView or whether one shall use a background thread and access it via returned executor's execute method, one can use the runOnUiThread parameter of the configure(java.lang.String, android.webkit.WebView, java.lang.String, java.lang.Boolean) method.

It is usually more comfortable to set the runOnUiThread parameter to true as one can make direct calls between WebView HTML content and other Android widgets. Whether that is safe depends on the minimal SDK you are targeting (24 and newer is safe). For now it is probably more useful to stick with verbose:

 Executor executor = Android.configure(null, view, null, false);
 executor.execute(new Runnable {
     public void run() {
        // access the HTML Content of your view
        runOnUiThread(new Runnable {
          // access native UI of your application
        });
     }
 });
 

This presenter is licensed under GPLv3 license - visit DukeScript website for commercial licenses and support.

Parameters:

licenseKey - ignored

view - the WebView to configure and make ready for access from Java code

page - the initial page to load - usually read from assets - e.g. the URL looks like: file:///android_asset/mypage.html

runOnUiThread - true to run all the communication with the HTML content of your view in Android UI thread, false to use a background thread (safer on SDK 23 and older), null to use the default which is the Android UI thread on SDK 24 and newer and background thread otherwise

Returns:

the executor to use to safely execute code inside of the HTML content of your view

Since:

1.3

create

@Deprecated
public static Fn.Presenter create(WebView view,
                                              String page)

Deprecated. Consider using configure(java.lang.String, android.webkit.WebView, java.lang.String, java.lang.Boolean) which offers more control over behavior of Android DukeScript presenter.

Parameters:

view - the view to configure

page - the page to load into the view or null

Returns:

presenter which also implements Executor interface

Since:

1.0

onCreate

public void onCreate(Bundle savedInstanceState)

Initializes the Activity by creating a WebView and setting it up to allow execution of DukeScript application. The configuration is performed in AndroidManifest.xml file. Sample definition looks like:

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="dstest"
    android:theme="@android:style/Theme.Black.NoTitleBar.Fullscreen">
    <activity android:name="com.dukescript.presenters.Android"
              android:configChanges="orientation|screenSize">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

    <meta-data android:name="loadPage" android:value="file:///android_asset/pages/index.html" />
    <meta-data android:name="loadClass" android:value="org.apidesign.bck2brwsr.dstest.AndroidMain" />
    <meta-data android:name="invoke" android:value="main" />
</application>
 

The file specifies fully qualified name of this activity and additional configuration parameters. Configuration section can define:

• loadPage - the HTML page to load on start
• loadClass - the fully qualified name of a class that contains the main initialization method
• invoke - name of static initialization method in the given class that will be invoked when the page is loaded and can access the objects in the specified HTML page
• runOnUiThread - optional parameter that can be set to true or false to specify whether to execute the code on standard UI thread (only possible on SDK 24 and newer) or on a background thread - more info.

To get more control over the WebView one can build the scene itself and use configure(java.lang.String, android.webkit.WebView, java.lang.String, java.lang.Boolean) factory method to initialize the view(s).

This presenter is licensed under GPLv3 license - visit DukeScript website for commercial licenses and support.

Overrides:

onCreate in class Activity

Parameters:

savedInstanceState - the state of the bundle, unused so far