iOS: DWG Viewer

The DWG Viewer emphasizes how to embed the framework into a stand alone application and covers basic viewing and editing capabilities.

Features

• Viewer object

• Load drawing

• Close drawing

• Change viewing modes

• Change layout background color

• Switch between model and sheets

DWG Viewer - Viewer object OBJ-C

The most important step is to embed the viewer object and connect it with the host application. The viewer object CFxARESDocumentView can be used and configured in a simple view controller or inside the storyboard. This object is a member of the host application. The host application’s main class is the AppDelegate that has a synergy with a class named CFxAresDelegate . The CFxAresDelegate is derived from CFxARESInstanceDelegate, is the core piece between the host application and the kernel SDK and must be initialized with the singleton [CFxARESInstance instance] from the main class. The kernel SDK starts to render the drawing into the CFxARESDocumentView object that will be accessed by getDocumentView from the CFxAresDelegate when a document is loaded successfully.

Note: The host application’s main class may be directly used as CFxARESInstanceDelegate but it is easier to split both parts of the application.

File: ViewController.h

@property (weak, nonatomic) IBOutlet CFxARESDocumentView *m_DocumentView;

File: AppDelegate.m

-(void)startARESInstance:(NSString*)login password:(NSString*)password
{
    ...
    aresDelegate = [[CFxAresDelegate alloc] init];
    [CFxARESInstance instance].delegate = aresDelegate;
    
    inputDelegate = [[UserInputDelegate alloc] init];
    [[CFxARESInstance instance] userInput].inputDelegate = inputDelegate;
    
    [[CFxARESInstance instance] startWith:login password:password];
    
    uiDelegate = [[CommonUIDelegate alloc] init];
    [CFxCommonUI startWithDelegate:uiDelegate];
    ...
}

File: CFxAresDelegate.m

-(CFxARESDocumentView*)getDocumentView
{
    return [self getMainView].m_DocumentView;
}

DWG Viewer - Load drawing OBJ-C

The DWG Viewer reads all drawings from the Support folder of the IPA. This may result in a slower opening and rendering time. It is recommended to load drawings from a local or external folder of the device. The drawing is loaded with the OPEN command using the runCommand method of the singleton [CFxARESInstance instance]. Once the drawing is loaded the CFxAresDelegate triggers documentCreated and the CFxARESDocumentView can become visible. This is the time when additional user interfaces can show up or drawing content can be accessed. In general, the CFxAresDelegate informs the host application about all important drawing events.

Note: The framework supports opening DWG, DXF and DWT files.

File: CFxAresDelegate.m

-(void)documentCreated
{
    [CFxARESInstance runOnUiThread:^
    {
        [self getMainView].m_DocumentView.hidden = NO;
    }];
}

File: ViewController.m

 -(void)viewDidAppear:(BOOL)animated
 {
    ...
    NSString* command = @"_OPEN\n";
    command = [command stringByAppendingString:document];
    command = [command stringByAppendingString:@"\n"];

    [[CFxARESInstance instance] runCommand:command];
    ...
}

DWG Viewer - Close active drawing OBJ-C

The active drawing is closed with the CLOSE command. When the document is closed the CFxARESDelegate triggers documentDestroyed , the drawing is removed from the memory and the CFxARESDocumentView  can become hidden. The host application can set up the user interface for a new drawing like switching between state view controllers.

File: CFxAresDelegate.m

-(void)documentDestroyed
{
    [CFxARESInstance runOnUiThread:^
    {
        [self getMainView].m_DocumentView.hidden = YES;
        ...
    }];
}

File: ViewController.m

-(IBAction)onClosePressed:(id)sender
{
    ...
    [[CFxARESInstance instance] runCommand:@"_CLOSE\n"];
}

DWG Viewer - Change viewing modes OBJ-C

It is not necessary to implement viewing gestures. The framework comes with a set of basic finger gestures to change the active view of the drawing. It supports zooming in and out but has to know if it runs in Pan or Orbit mode. The viewing mode can be switched with a Diesel expression that can be executed with the runCommand method of the singleton [CFxARESInstance instance].

File: ViewController.m

-(void)SwitchViewModeToPan:(BOOL)panMode
{
    if (m_bPanMode != panMode)
    {
        m_bPanMode = panMode;
        ...
        [[CFxARESInstance instance] runCommand:@"'2dmode $M=$(if,$(and,$(getvar,2dmode),1),$(-,$(getvar,2dmode),1),$(+,$(getvar,2dmode),1))"];
    }
}

Note:  The kernel SDK also provides commands like ZOOM or PAN to achieve similar results.