C4 camera capture - problems when coming back to the view

Question

I'm working on an app with several subviews.

Currently I have 4 subviews. Here it the C4Workspace code to set them up

//TakePhoto
    takePhoto= [TakePhoto new];
    takePhoto.canvas.frame=CGRectMake(0, 0, self.canvas.width, self.canvas.height);
    takePhoto.canvas.userInteractionEnabled = YES;
    [takePhoto transferVariables:1 topBarFromTop:TopBarFromTopDefault topBarHeight:TopNavBarHeightDefault bottomBarHeight:BottomBarHeightDefault navBarColor:navBarColorDefault navigationColor:navigationColorDefault typeColor:typeColorDefault fatFont:fatFontDefault normalFont:normalFontDefault iconTakePhoto:iconTakePhoto iconClose:iconClose iconBack:iconBack];
    [takePhoto setup];
    [takePhoto cameraSetup];
    [self.canvas addSubview:takePhoto.canvas];

    //CropPhoto
    cropPhoto=[CropPhoto new];
    cropPhoto.canvas.frame=CGRectMake(0, 0, self.canvas.width, self.canvas.height);
    cropPhoto.canvas.userInteractionEnabled=YES;
    [cropPhoto transferVariables:1 topBarFroTop:TopBarFromTopDefault topBarHeight:TopNavBarHeightDefault bottomBarHeight:BottomBarHeightDefault navBarColor:navBarColorDefault navigationColor:navigationColorDefault typeColor:typeColorDefault overlayColor:overlayColorDefault fatFont:fatFontDefault normalFont:normalFontDefault iconClose:iconClose iconBack:iconBack iconOk:iconOk];
    [self.canvas addSubview:cropPhoto.canvas];
    cropPhoto.canvas.hidden= YES;

    //AssignPhoto
    assignLetter=[AssignLetter new];
    assignLetter.canvas.frame=CGRectMake(0, 0, self.canvas.width, self.canvas.height);
    assignLetter.canvas.userInteractionEnabled=YES;
    [assignLetter transferVariables:1 topBarFroTop:TopBarFromTopDefault topBarHeight:TopNavBarHeightDefault bottomBarHeight:BottomBarHeightDefault navBarColor:navBarColorDefault navigationColor:navigationColorDefault typeColor:typeColorDefault highlightColor:highlightColorDefault fatFont:fatFontDefault normalFont:normalFontDefault iconClose:iconClose iconBack:iconBack iconOk:iconOk iconSettings:iconSettings];

    [self.canvas addSubview:assignLetter.canvas ];
    assignLetter.canvas.hidden=YES;

    //AlphabetView
    alphabetView=[AlphabetView new];
    alphabetView.canvas.frame= CGRectMake(0, 0, self.canvas.width, self.canvas.height);
    alphabetView.canvas.userInteractionEnabled=YES;
    [alphabetView transferVaribles:1 topBarFromTop:TopBarFromTopDefault topBarHeight:TopNavBarHeightDefault bottomBarHeight:BottomBarHeightDefault navBarColor:navBarColorDefault navigationColor:navigationColorDefault typeColor:typeColorDefault darkenColor:darkenColorDefault fatFont:fatFontDefault normalFont:normalFontDefault iconClose:iconClose iconBack:iconBack iconMenu:iconMenu iconTakePhoto:iconTakePhoto iconAlphabetInfo:iconAlphabetInfo iconShareAlphabet:iconShareAlphabet iconWritePostcard:iconWritePostcard iconMyPostcards:iconMyPostcards iconMyAlphabets:iconMyAlphabets];
    [self.canvas addSubview:alphabetView.canvas];
    alphabetView.canvas.hidden=YES;

//the methods to listen for from all other canvasses
    [self listenFor:@"goToTakePhoto" andRunMethod:@"goToTakePhoto"];
    [self listenFor:@"goToCropPhoto" andRunMethod:@"goToCropPhoto"];
    [self listenFor:@"goToAssignPhoto" andRunMethod:@"goToAssignPhoto"];
    [self listenFor:@"goToAlphabetsView" andRunMethod:@"goToAlphabetsView"];

This main workspace also has the following functions to switch between the views

-(void)goToTakePhoto{
    [takePhoto resetCounter];
    [takePhoto setup];

    C4Log(@"TakePhoto");
    takePhoto.canvas.hidden=NO;
    cropPhoto.canvas.hidden=YES;
    assignLetter.canvas.hidden=YES;
    alphabetView.canvas.hidden=YES;
}
-(void)goToCropPhoto{
    C4Log(@"going to CropPhoto");
    [cropPhoto displayImage:takePhoto.img];
    [cropPhoto setup];
    takePhoto.canvas.hidden=YES;
    cropPhoto.canvas.hidden=NO;
    assignLetter.canvas.hidden=YES;
    alphabetView.canvas.hidden=YES;
}
-(void)goToAssignPhoto{
    C4Log(@"AssignPhoto");
    [assignLetter setup];
    [assignLetter drawCurrentAlphabet:currentAlphabet];
    [assignLetter drawCroppedPhoto:cropPhoto.croppedPhoto];
    takePhoto.canvas.hidden=YES;
    cropPhoto.canvas.hidden=YES;
    assignLetter.canvas.hidden=NO;
    alphabetView.canvas.hidden=YES;
}
-(void)goToAlphabetsView{
    C4Log(@"AlphabetsView");
    [alphabetView setup];
    [alphabetView drawCurrentAlphabet:assignLetter.currentAlphabet];
    takePhoto.canvas.hidden=YES;
    cropPhoto.canvas.hidden=YES;
    assignLetter.canvas.hidden=YES;
    alphabetView.canvas.hidden=NO;
}

the first view is taking the photo very similar to the tutorial (I added a reset counter for the camera because I noticed that the button to take the photo always sends the notification twice when it was tapped).

-(void) setup{
photoButtonImage=iconTakePhoto;
    photoButtonImage.height=45;
    photoButtonImage.width=90;
    photoButtonImage.center=CGPointMake(self.canvas.width/2, self.canvas.height-bottomBarHeight/2);
    [self.canvas addImage:photoButtonImage];
    //gestures to take the photo
    [self listenFor:@"touchesBegan" fromObject:photoButtonImage andRunMethod:@"captureImage"];
    [self numberOfTouchesRequired:1 forGesture:@"capture"];
    [self listenFor:@"imageWasCaptured" fromObject:cam andRunMethod:@"goToCropPhoto"];
}

-(void)cameraSetup{
    cam = [C4Camera cameraWithFrame:CGRectMake(0,topBarFromTop+topBarHeight, self.canvas.width, self.canvas.height-(topBarHeight+bottomBarHeight+topBarFromTop))];
    cam.cameraPosition = CAMERABACK;
    [self.canvas addCamera:cam];
    [cam initCapture];
    counter=0;
}
-(void) captureImage{
    [cam captureImage];
    C4Log(@"capturing image");
}
-(void)resetCounter{
    counter=0;
}

this works fine as long as I navigate back to that view from a C4Label but not if I'm navigating back from an image. Even though I'm running the exact same functions when touching both. It looks like this:

//image as navigation element
takePhotoButton=iconTakePhoto;
    takePhotoButton.width=60;
    takePhotoButton.center=CGPointMake(takePhotoButton.width/2+5, bottomNavBar.center.y);
    [self.canvas addImage:takePhotoButton];
    [self listenFor:@"touchesBegan" fromObject:takePhotoButton andRunMethod:@"goToTakePhoto"];

//label as navigation element
takePhoto=[C4Label labelWithText:@"take Photo" font: normalFont];
    takePhoto.center=CGPointMake(self.canvas.width-(takePhoto.width/2+5), topNavBar.center.y);
    [self.canvas addLabel:takePhoto ];
    [self listenFor:@"touchesBegan" fromObject:takePhoto andRunMethod:@"goToTakePhoto"];

and lastly this is the function inside that view that sends te notification

-(void) goToTakePhoto{
    C4Log(@"goToTakePhoto");
    [self removeFromView]; //removes the currently displayed items from being displayed
    [self postNotification:@"goToTakePhoto"];
}

I can make it work for now using the label but it would be so much nicer to use a C4Image as a button.... Any ideas? Full code available on Github: http://github.com/susemiessner/Urban-Alphabets/tree/master/urbanAlphabetsII

Answer 1

I just found the answer to this one: When coming back to the camera view the old

[self listenFor:@"imageWasCaptured" fromObject:cam andRunMethod:@"goToCropPhoto"];

was still active, so it thinks I already captured an image from the camera, which is not true. So the solution is when I leave the view I just have to disable that using this code

[self stopListeningFor:@"imageWasCaptured" object:cam];

that does the entire magic!