我尝试将自定义UIView添加到CALayer但未呈现。
我没有将自定义视图添加到其他视图。相反，我尝试将其直接添加到CALayer。
如果我确实将自定义视图添加到另一个视图（即[self.view addSubview:customView]），它可以工作，但由于某种原因，在触摸屏幕的那一刻开始导致崩溃。
基本上是
[self.view addSubview:customView];
[layer addSublayer:customView.layer]; //Causes crashes the minute the screen is touched
以下是代码：
CustomView *customView = [[CustomView alloc] initWithFrame:frame];
//I'm not adding the custom view to another view
//Instead I'm trying to add it to a CALayer
CALayer *layer = [CALayer layer];
[Layer setFrame:frame2];
[layer addSublayer: customView.layer];
P.S。我目前的解决方法是将UIView转换为UIImage并将其添加到CALayer。
Belo是自定义的UIView代码：
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
self.font = [UIFont fontWithName:ARCVIEW_DEFAULT_FONT_NAME size:ARCVIEW_DEFAULT_FONT_SIZE];
self.text = @"Curva Style Label";
NSLog(@"FONT = %@, TEXT = %@", self.font, self.text);
self.radius = ARCVIEW_DEFAULT_RADIUS;
self.showsGlyphBounds = NO;
self.showsLineMetrics = NO;
self.dimsSubstitutedGlyphs = NO;
self.color = [UIColor whiteColor];
self.arcSize = ARCVIEW_DEFAULT_ARC_SIZE;
self.shiftH = self.shiftV = 0.0f;
}
return self;
}
- (id)initWithFrame:(CGRect)frame font:(UIFont *)font text:(NSString *)text radius:(float)radius arcSize:(float)arcSize color:(UIColor *)color{
self = [super initWithFrame:frame];
if (self) {
self.font = font;
self.text = text;
self.radius = radius;
self.showsGlyphBounds = NO;// Border add for each Text
self.showsLineMetrics = NO;
self.dimsSubstitutedGlyphs = NO;
self.color = color;
self.arcSize = arcSize;
self.shiftH = self.shiftV = 0.0f;
}
return self;
}
typedef struct GlyphArcInfo {
CGFloat width;
CGFloat angle; // in radians
} GlyphArcInfo;
static void PrepareGlyphArcInfo(CTLineRef line, CFIndex glyphCount, GlyphArcInfo *glyphArcInfo, CGFloat arcSizeRad)
{ NSArray * runArray =（NSArray *）CTLineGetGlyphRuns（line）;
// Examine each run in the line, updating glyphOffset to track how far along the run is in terms of glyphCount.
CFIndex glyphOffset = 0;
for (id run in runArray) {
CFIndex runGlyphCount = CTRunGetGlyphCount((CTRunRef)run);
// Ask for the width of each glyph in turn.
CFIndex runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
glyphArcInfo[runGlyphIndex + glyphOffset].width = CTRunGetTypographicBounds((CTRunRef)run, CFRangeMake(runGlyphIndex, 1), NULL, NULL, NULL);
}
glyphOffset += runGlyphCount;
}
double lineLength = CTLineGetTypographicBounds(line, NULL, NULL, NULL);
CGFloat prevHalfWidth = glyphArcInfo[0].width / 2.0;
glyphArcInfo[0].angle = (prevHalfWidth / lineLength) * arcSizeRad;
// Divide the arc into slices such that each one covers the distance from one glyph's center to the next.
CFIndex lineGlyphIndex = 1;
for (; lineGlyphIndex < glyphCount; lineGlyphIndex++) {
CGFloat halfWidth = glyphArcInfo[lineGlyphIndex].width / 2.0;
CGFloat prevCenterToCenter = prevHalfWidth + halfWidth;
glyphArcInfo[lineGlyphIndex].angle = (prevCenterToCenter / lineLength) * arcSizeRad;
prevHalfWidth = halfWidth;
}
}
-(void)setText:(NSString *)text{
//[_string release];
_string = text;
[self setNeedsDisplay];
}
-(void)setArcSize:(CGFloat)degrees{
_arcSize = degrees * M_PI/180.0;
}
-(CGFloat)arcSize{
NSLog(@"arcSize %f",_arcSize * 180.0/M_PI);
return _arcSize * 180.0/M_PI;
}
- (void)drawRect:(CGRect)rect {
// Don't draw if we don't have a font or string
NSLog(@"FONT = %@, TEXT = %@", self.font, self.text);
if (self.font == NULL || self.text == NULL)
return;
// Initialize the text matrix to a known value
CGContextRef context = UIGraphicsGetCurrentContext();
//Reset the transformation
//Doing this means you have to reset the contentScaleFactor to 1.0
CGAffineTransform t0 = CGContextGetCTM(context);
CGContextSetShadowWithColor(context, CGSizeMake(self.xOffsetShadow, self.yOffsetShadow), self.blurShadow, self.shadowColor.CGColor);
CGFloat xScaleFactor = t0.a > 0 ? t0.a : -t0.a;
CGFloat yScaleFactor = t0.d > 0 ? t0.d : -t0.d;
t0 = CGAffineTransformInvert(t0);
if (xScaleFactor != 1.0 || yScaleFactor != 1.0)
t0 = CGAffineTransformScale(t0, xScaleFactor, yScaleFactor);
CGContextConcatCTM(context, t0);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
if(ARCVIEW_DEBUG_MODE){
// Draw a black background (debug)
CGContextSetFillColorWithColor(context, [UIColor blackColor].CGColor);
CGContextFillRect(context, self.layer.bounds);
}
NSAttributedString *attStr = self.attributedString;
CFAttributedStringRef asr = (__bridge CFAttributedStringRef)attStr;
CTLineRef line = CTLineCreateWithAttributedString(asr);
assert(line != NULL);
CFIndex glyphCount = CTLineGetGlyphCount(line);
if (glyphCount == 0) {
CFRelease(line);
return;
}
GlyphArcInfo * glyphArcInfo = (GlyphArcInfo*)calloc(glyphCount, sizeof(GlyphArcInfo));
PrepareGlyphArcInfo(line, glyphCount, glyphArcInfo, _arcSize);
// Move the origin from the lower left of the view nearer to its center.
CGContextSaveGState(context);
CGContextTranslateCTM(context, CGRectGetMidX(rect)+_shiftH, CGRectGetMidY(rect)+_shiftV);
if(ARCVIEW_DEBUG_MODE){
// Stroke the arc in red for verification.
CGContextBeginPath(context);
CGContextAddArc(context, 0.0, 0.0, self.radius, M_PI_2+_arcSize/2.0, M_PI_2-_arcSize/2.0, 1);
CGContextSetRGBStrokeColor(context, 1.0, 0.0, 0.0, 1.0);
CGContextStrokePath(context);
}
// Rotate the context 90 degrees counterclockwise (per 180 degrees)
CGContextRotateCTM(context, _arcSize/2.0);
// Now for the actual drawing. The angle offset for each glyph relative to the previous glyph has already been calculated; with that information in hand, draw those glyphs overstruck and centered over one another, making sure to rotate the context after each glyph so the glyphs are spread along a semicircular path.
CGPoint textPosition = CGPointMake(0.0, self.radius);
CGContextSetTextPosition(context, textPosition.x, textPosition.y);
CFArrayRef runArray = CTLineGetGlyphRuns(line);
CFIndex runCount = CFArrayGetCount(runArray);
CFIndex glyphOffset = 0;
CFIndex runIndex = 0;
for (; runIndex < runCount; runIndex++) {
CTRunRef run = (CTRunRef)CFArrayGetValueAtIndex(runArray, runIndex);
CFIndex runGlyphCount = CTRunGetGlyphCount(run);
Boolean drawSubstitutedGlyphsManually = false;
CTFontRef runFont = CFDictionaryGetValue(CTRunGetAttributes(run), kCTFontAttributeName);
// Determine if we need to draw substituted glyphs manually. Do so if the runFont is not the same as the overall font.
if (self.dimsSubstitutedGlyphs && ![self.font isEqual:(__bridge UIFont *)runFont]) {
drawSubstitutedGlyphsManually = true;
}
CFIndex runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
CFRange glyphRange = CFRangeMake(runGlyphIndex, 1);
CGContextRotateCTM(context, -(glyphArcInfo[runGlyphIndex + glyphOffset].angle));
// Center this glyph by moving left by half its width.
CGFloat glyphWidth = glyphArcInfo[runGlyphIndex + glyphOffset].width;
CGFloat halfGlyphWidth = glyphWidth / 2.0;
CGPoint positionForThisGlyph = CGPointMake(textPosition.x - halfGlyphWidth, textPosition.y);
// Glyphs are positioned relative to the text position for the line, so offset text position leftwards by this glyph's width in preparation for the next glyph.
textPosition.x -= glyphWidth;
CGAffineTransform textMatrix = CTRunGetTextMatrix(run);
textMatrix.tx = positionForThisGlyph.x;
textMatrix.ty = positionForThisGlyph.y;
CGContextSetTextMatrix(context, textMatrix);
if (!drawSubstitutedGlyphsManually) {
CTRunDraw(run, context, glyphRange);
}
else {
// We need to draw the glyphs manually in this case because we are effectively applying a graphics operation by setting the context fill color. Normally we would use kCTForegroundColorAttributeName, but this does not apply as we don't know the ranges for the colors in advance, and we wanted demonstrate how to manually draw.
CGFontRef cgFont = CTFontCopyGraphicsFont(runFont, NULL);
CGGlyph glyph;
CGPoint position;
CTRunGetGlyphs(run, glyphRange, &glyph);
CTRunGetPositions(run, glyphRange, &position);
CGContextSetFont(context, cgFont);
CGContextSetFontSize(context, CTFontGetSize(runFont));
CGContextSetRGBFillColor(context, 0.25, 0.25, 0.25, 0.5);
CGContextShowGlyphsAtPositions(context, &glyph, &position, 1);
CFRelease(cgFont);
}
// Draw the glyph bounds
if ((self.showsGlyphBounds) != 0) {
CGRect glyphBounds = CTRunGetImageBounds(run, context, glyphRange);
CGContextSetRGBStrokeColor(context, 0.0, 0.0, 1.0, 1.0);
CGContextStrokeRect(context, glyphBounds);
}
// Draw the bounding boxes defined by the line metrics
if ((self.showsLineMetrics) != 0) {
CGRect lineMetrics;
CGFloat ascent, descent;
CTRunGetTypographicBounds(run, glyphRange, &ascent, &descent, NULL);
// The glyph is centered around the y-axis
lineMetrics.origin.x = -halfGlyphWidth;
lineMetrics.origin.y = positionForThisGlyph.y - descent;
lineMetrics.size.width = glyphWidth;
lineMetrics.size.height = ascent + descent;
CGContextSetRGBStrokeColor(context, 0.0, 1.0, 0.0, 1.0);
CGContextStrokeRect(context, lineMetrics);
}
}
glyphOffset += runGlyphCount;
}
CGContextSetFillColorWithColor(context, [UIColor clearColor].CGColor);
CGContextSetAlpha(context,0.0);
CGContextFillRect(context, rect);
CGContextRestoreGState(context);
free(glyphArcInfo);
CFRelease(line);
}
@synthesize font = _font;
@synthesize text = _string;
@synthesize radius = _radius;
@synthesize color = _color;
@synthesize arcSize = _arcSize;
@synthesize shiftH = _shiftH;
@synthesize shiftV = _shiftV;
@synthesize shadowColor = _shadowColor;
@synthesize xOffsetShadow = _xOffsetShadow;
@synthesize blurShadow = _blurShadow;
@synthesize yOffsetShadow = _yOffsetShadow;
@dynamic attributedString;
- (NSAttributedString *)attributedString {
// Create an attributed string with the current font and string.
assert(self.font != nil);
assert(self.text != nil);
// Create our attributes...
// font
CTFontRef fontRef = CTFontCreateWithName((CFStringRef)self.font.fontName, self.font.pointSize, NULL);
// color
CGColorRef colorRef = self.color.CGColor;
// pack it into attributes dictionary
NSDictionary *attributesDict = [NSDictionary dictionaryWithObjectsAndKeys:
(__bridge id)fontRef, (id)kCTFontAttributeName,
colorRef, (id)kCTForegroundColorAttributeName,
nil];
assert(attributesDict != nil);
// Create the attributed string
NSAttributedString *attrString = [[NSAttributedString alloc] initWithString:self.text attributes:attributesDict];
return attrString;
}
@end
答案 0 :(得分：6)
你应该问问题，而不是你试图解决问题：
[self.view addSubview:customView];
[layer addSublayer:customView.layer];
//Causes crashes the minute the screen is touched
您不需要添加子视图和图层，只需添加子视图即可。你正在做的是断开某些事情，或者过度纠正某些事情并产生不必要的行为。
如果要将图层添加到图层，则使用图层而不是视图。视图拥有它们的图层，您不应该尝试断开它们，或者在取消分配视图时保留图层。
因此，理想情况下，创建一个CALayer子类，并将当前所有代码移动到其drawInContext:方法中。看起来您基本上可以复制并粘贴它，因为您当前的所有代码都会被吸引到CGContext。