Screen manager

[BrettyWhite]

Fixes #782

This PR is ready for review.

Risk

This PR makes minor API changes.

Testing Plan

• This code snippet can be used to test the manager:

// Begin update transaction
proxy.getScreenManager().beginTransaction();

//proxy.getScreenManager().setDisplayLayout(PredefinedLayout.DOUBLE_GRAPHIC_WITH_SOFTBUTTONS);

// Set text fields
proxy.getScreenManager().setTextField1("It is");
proxy.getScreenManager().setTextField2("Wednesday");
proxy.getScreenManager().setTextField3("My");
proxy.getScreenManager().setTextField4("Dudes");


// Set primary graphic
proxy.getScreenManager().setPrimaryGraphic(new SdlArtwork("image1", FileType.GRAPHIC_PNG, R.drawable.image1, true));


// Create softButtonObject1
SoftButtonState softButtonState1 = new SoftButtonState("object1-state1", "it is", new SdlArtwork(ICON_FILENAME, FileType.GRAPHIC_PNG, R.mipmap.ic_launcher, false));
SoftButtonState softButtonState2 = new SoftButtonState("object1-state2", "Wed", new SdlArtwork(IMAGE1_FILENAME, FileType.GRAPHIC_PNG, R.drawable.image1, false));
SoftButtonObject softButtonObject1 = new SoftButtonObject("object1", Arrays.asList(softButtonState1, softButtonState2), softButtonState1.getName(), new SoftButtonObject.OnEventListener() {
    @Override
    public void onPress(SoftButtonObject softButtonObject, OnButtonPress onButtonPress) {
        softButtonObject.transitionToNextState();
    }

    @Override
    public void onEvent(SoftButtonObject softButtonObject, OnButtonEvent onButtonEvent) {

    }
});


// Create softButtonObject2
SoftButtonState softButtonState3 = new SoftButtonState("object2-state1", "my", new SdlArtwork(IMAGE2_FILENAME, FileType.GRAPHIC_PNG, R.drawable.image2, false));
SoftButtonState softButtonState4 = new SoftButtonState("object2-state2", "dudes!", null);
SoftButtonObject softButtonObject2 = new SoftButtonObject("object2", Arrays.asList(softButtonState3, softButtonState4), softButtonState3.getName(), null);
softButtonObject2.setOnEventListener(new SoftButtonObject.OnEventListener() {
    @Override
    public void onPress(SoftButtonObject softButtonObject, OnButtonPress onButtonPress) {
        softButtonObject.transitionToNextState();
    }

    @Override
    public void onEvent(SoftButtonObject softButtonObject, OnButtonEvent onButtonEvent) {

    }
});


// Set the soft button objects
proxy.getScreenManager().setSoftButtonObjects(Arrays.asList(softButtonObject1, softButtonObject2));


// Commit update transaction
proxy.getScreenManager().commit(new CompletionListener() {
    @Override
    public void onComplete(boolean success) {
        Log.i(TAG, "UPDATES COMPLETE: " + success);

    }
});

Summary

This PR implements the ScreenManager as described in the proposal.

• Implemented SoftButtonManager
• Implemented TextAndGraphicManager
• Implemented ScreenManager
• Added test classes to test the functionalties for the managers

CLA

• I have signed the CLA

[joeygrover]

Should there be a check against if the submanagers failed to initialize so that the screen manager transitions to error state?

[BrettyWhite]

now it sets the screen manager state to ERROR

[joeygrover]

If both managers are not null and are in the ERROR state the ScreenManager will transition to the READY state after this call. However, this callback is essentially pointless at this point. Both the SoftButtonManager and TextAndGraphicManager will be in the READY state after their constructors return. See here, the start() methods are not used in either managers and will set the completionListneer, check state, realize they are in READY state (as at this point neither have a logic path to allow them to go into ERROR state), notify the callback, then clear the reference.

[BrettyWhite]

The start methods are used by both:
https://github.com/smartdevicelink/sdl_android/blob/feature/screen_manager/sdl_android/src/main/java/com/smartdevicelink/api/screen/ScreenManager.java#L55

[bilal-alsharifi]

The only place that I can think of for switching to state ERROR is that when they cannot retrieve capabilities.

[joeygrover]

The start method is called, but it is not overridden (not used) in either submanager so they will always return immediately.

[joeygrover]

All vars should be considered @nonnull right?

[joeygrover]

Move the declaration for TexFieldName name; before the for loop and just set the name through each iteration rather than create a new reference.

[joeygrover]

Let's change this as follows:

public static final int SETTING_UP = 0x00, READY = 0x30, LIMITED = 0x50, SHUTDOWN = 0x80, ERROR = 0xC0;