src/video/uikit/SDL_uikitviewcontroller.m

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2015 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/
#include "../../SDL_internal.h"

#if SDL_VIDEO_DRIVER_UIKIT

#include "SDL_video.h"
#include "SDL_assert.h"
#include "SDL_hints.h"
#include "../SDL_sysvideo.h"
#include "../../events/SDL_events_c.h"

#import "SDL_uikitviewcontroller.h"
#import "SDL_uikitmessagebox.h"
#include "SDL_uikitvideo.h"
#include "SDL_uikitmodes.h"
#include "SDL_uikitwindow.h"

#if SDL_IPHONE_KEYBOARD
#include "keyinfotable.h"
#endif

@implementation SDL_uikitviewcontroller {
    CADisplayLink *displayLink;
    int animationInterval;
    void (*animationCallback)(void*);
    void *animationCallbackParam;

#if SDL_IPHONE_KEYBOARD
    UITextField *textField;
#endif
}

@synthesize window;

- (instancetype)initWithSDLWindow:(SDL_Window *)_window
{
    if (self = [super initWithNibName:nil bundle:nil]) {
        self.window = _window;

#if SDL_IPHONE_KEYBOARD
        [self initKeyboard];
#endif
    }
    return self;
}

- (void)dealloc
{
#if SDL_IPHONE_KEYBOARD
    [self deinitKeyboard];
#endif
}

- (void)setAnimationCallback:(int)interval
                    callback:(void (*)(void*))callback
               callbackParam:(void*)callbackParam
{
    [self stopAnimation];

    animationInterval = interval;
    animationCallback = callback;
    animationCallbackParam = callbackParam;

    if (animationCallback) {
        [self startAnimation];
    }
}

- (void)startAnimation
{
    displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(doLoop:)];
    [displayLink setFrameInterval:animationInterval];
    [displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
}

- (void)stopAnimation
{
    [displayLink invalidate];
    displayLink = nil;
}

- (void)doLoop:(CADisplayLink*)sender
{
    /* Don't run the game loop while a messagebox is up */
    if (!UIKit_ShowingMessageBox()) {
        animationCallback(animationCallbackParam);
    }
}

- (void)loadView
{
    /* Do nothing. */
}

- (void)viewDidLayoutSubviews
{
    const CGSize size = self.view.bounds.size;
    int w = (int) size.width;
    int h = (int) size.height;

    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_RESIZED, w, h);
}

- (NSUInteger)supportedInterfaceOrientations
{
    return UIKit_GetSupportedOrientations(window);
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)orient
{
    return ([self supportedInterfaceOrientations] & (1 << orient)) != 0;
}

- (BOOL)prefersStatusBarHidden
{
    return (window->flags & (SDL_WINDOW_FULLSCREEN|SDL_WINDOW_BORDERLESS)) != 0;
}

- (UIStatusBarStyle)preferredStatusBarStyle
{
    /* We assume most SDL apps don't have a bright white background. */
    return UIStatusBarStyleLightContent;
}

/*
 ---- Keyboard related functionality below this line ----
 */
#if SDL_IPHONE_KEYBOARD

@synthesize textInputRect;
@synthesize keyboardHeight;
@synthesize keyboardVisible;

/* Set ourselves up as a UITextFieldDelegate */
- (void)initKeyboard
{
    textField = [[UITextField alloc] initWithFrame:CGRectZero];
    textField.delegate = self;
    /* placeholder so there is something to delete! */
    textField.text = @" ";

    /* set UITextInputTrait properties, mostly to defaults */
    textField.autocapitalizationType = UITextAutocapitalizationTypeNone;
    textField.autocorrectionType = UITextAutocorrectionTypeNo;
    textField.enablesReturnKeyAutomatically = NO;
    textField.keyboardAppearance = UIKeyboardAppearanceDefault;
    textField.keyboardType = UIKeyboardTypeDefault;
    textField.returnKeyType = UIReturnKeyDefault;
    textField.secureTextEntry = NO;

    textField.hidden = YES;
    keyboardVisible = NO;

    NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
    [center addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [center addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)setView:(UIView *)view
{
    [super setView:view];

    [view addSubview:textField];

    if (keyboardVisible) {
        [self showKeyboard];
    }
}

- (void)deinitKeyboard
{
    NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
    [center removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [center removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

/* reveal onscreen virtual keyboard */
- (void)showKeyboard
{
    keyboardVisible = YES;
    if (textField.window) {
        [textField becomeFirstResponder];
    }
}

/* hide onscreen virtual keyboard */
- (void)hideKeyboard
{
    keyboardVisible = NO;
    [textField resignFirstResponder];
}

- (void)keyboardWillShow:(NSNotification *)notification
{
    CGRect kbrect = [[notification userInfo][UIKeyboardFrameBeginUserInfoKey] CGRectValue];

    /* The keyboard rect is in the coordinate space of the screen/window, but we
     * want its height in the coordinate space of the view. */
    kbrect = [self.view convertRect:kbrect fromView:nil];

    [self setKeyboardHeight:(int)kbrect.size.height];
}

- (void)keyboardWillHide:(NSNotification *)notification
{
    [self setKeyboardHeight:0];
}

- (void)updateKeyboard
{
    CGAffineTransform t = self.view.transform;
    CGPoint offset = CGPointMake(0.0, 0.0);
    CGRect frame = UIKit_ComputeViewFrame(window, self.view.window.screen);

    if (self.keyboardHeight) {
        int rectbottom = self.textInputRect.y + self.textInputRect.h;
        int keybottom = self.view.bounds.size.height - self.keyboardHeight;
        if (keybottom < rectbottom) {
            offset.y = keybottom - rectbottom;
        }
    }

    /* Apply this view's transform (except any translation) to the offset, in
     * order to orient it correctly relative to the frame's coordinate space. */
    t.tx = 0.0;
    t.ty = 0.0;
    offset = CGPointApplyAffineTransform(offset, t);

    /* Apply the updated offset to the view's frame. */
    frame.origin.x += offset.x;
    frame.origin.y += offset.y;

    self.view.frame = frame;
}

- (void)setKeyboardHeight:(int)height
{
    keyboardVisible = height > 0;
    keyboardHeight = height;
    [self updateKeyboard];
}

/* UITextFieldDelegate method.  Invoked when user types something. */
- (BOOL)textField:(UITextField *)_textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    NSUInteger len = string.length;

    if (len == 0) {
        /* it wants to replace text with nothing, ie a delete */
        SDL_SendKeyboardKey(SDL_PRESSED, SDL_SCANCODE_BACKSPACE);
        SDL_SendKeyboardKey(SDL_RELEASED, SDL_SCANCODE_BACKSPACE);
    } else {
        /* go through all the characters in the string we've been sent and
         * convert them to key presses */
        int i;
        for (i = 0; i < len; i++) {
            unichar c = [string characterAtIndex:i];
            Uint16 mod = 0;
            SDL_Scancode code;

            if (c < 127) {
                /* figure out the SDL_Scancode and SDL_keymod for this unichar */
                code = unicharToUIKeyInfoTable[c].code;
                mod  = unicharToUIKeyInfoTable[c].mod;
            } else {
                /* we only deal with ASCII right now */
                code = SDL_SCANCODE_UNKNOWN;
                mod = 0;
            }

            if (mod & KMOD_SHIFT) {
                /* If character uses shift, press shift down */
                SDL_SendKeyboardKey(SDL_PRESSED, SDL_SCANCODE_LSHIFT);
            }

            /* send a keydown and keyup even for the character */
            SDL_SendKeyboardKey(SDL_PRESSED, code);
            SDL_SendKeyboardKey(SDL_RELEASED, code);

            if (mod & KMOD_SHIFT) {
                /* If character uses shift, press shift back up */
                SDL_SendKeyboardKey(SDL_RELEASED, SDL_SCANCODE_LSHIFT);
            }
        }

        SDL_SendKeyboardText([string UTF8String]);
    }

    return NO; /* don't allow the edit! (keep placeholder text there) */
}

/* Terminates the editing session */
- (BOOL)textFieldShouldReturn:(UITextField*)_textField
{
    SDL_SendKeyboardKey(SDL_PRESSED, SDL_SCANCODE_RETURN);
    SDL_SendKeyboardKey(SDL_RELEASED, SDL_SCANCODE_RETURN);
    SDL_StopTextInput();
    return YES;
}

#endif

@end

/* iPhone keyboard addition functions */
#if SDL_IPHONE_KEYBOARD

static SDL_uikitviewcontroller *
GetWindowViewController(SDL_Window * window)
{
    if (!window || !window->driverdata) {
        SDL_SetError("Invalid window");
        return nil;
    }

    SDL_WindowData *data = (__bridge SDL_WindowData *)window->driverdata;

    return data.viewcontroller;
}

SDL_bool
UIKit_HasScreenKeyboardSupport(_THIS)
{
    return SDL_TRUE;
}

void
UIKit_ShowScreenKeyboard(_THIS, SDL_Window *window)
{
    @autoreleasepool {
        SDL_uikitviewcontroller *vc = GetWindowViewController(window);
        [vc showKeyboard];
    }
}

void
UIKit_HideScreenKeyboard(_THIS, SDL_Window *window)
{
    @autoreleasepool {
        SDL_uikitviewcontroller *vc = GetWindowViewController(window);
        [vc hideKeyboard];
    }
}

SDL_bool
UIKit_IsScreenKeyboardShown(_THIS, SDL_Window *window)
{
    @autoreleasepool {
        SDL_uikitviewcontroller *vc = GetWindowViewController(window);
        if (vc != nil) {
            return vc.isKeyboardVisible;
        }
        return SDL_FALSE;
    }
}

void
UIKit_SetTextInputRect(_THIS, SDL_Rect *rect)
{
    if (!rect) {
        SDL_InvalidParamError("rect");
        return;
    }

    @autoreleasepool {
        SDL_uikitviewcontroller *vc = GetWindowViewController(SDL_GetFocusWindow());
        if (vc != nil) {
            vc.textInputRect = *rect;

            if (vc.keyboardVisible) {
                [vc updateKeyboard];
            }
        }
    }
}


#endif /* SDL_IPHONE_KEYBOARD */

#endif /* SDL_VIDEO_DRIVER_UIKIT */

/* vi: set ts=4 sw=4 expandtab: */