我正在尝试按this answer创建一个分页滚动视图，显示下一张和上一张图像。
我创建了一个自定义的UIView类，并将UIScrollView添加为子视图。我有两个问题。
任何想法都会受到赞赏。
ModeSelectView.m
#import "ModeSelectView.h"
@implementation ModeSelectView
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self initView:frame];
}
return self;
}
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:(aDecoder)];
if (self) {
CGRect frame = self.frame;
[self initView:self.frame];
}
return self;
}
- (void)initView:(CGRect)frame
{
// Initialization code
// Create an array of images for the different modes
UIImage *imgTowerOnlyMode = [UIImage imageNamed:@"tower_only_mode_icon.png"];
UIImage *imgLocalMode = [UIImage imageNamed:@"local_mode_icon.png"];
UIImage *imgHowToPlay = [UIImage imageNamed:@"how_to_play_icon.png"];
NSArray *modeSelectIcons = @[imgTowerOnlyMode, imgLocalMode, imgHowToPlay];
int iconSize = 115;
// Center to center icon spacing
int viewSpacing = 115 * 1.75;
int frameWidth = 2*viewSpacing;
int contentWidth = 4*frameWidth;
int pageWidth = viewSpacing;
int verticalPadding = 10;
int pageHeight = iconSize + 2*verticalPadding;
//int viewWidth = frame.size.width;
int viewWidth = [[UIScreen mainScreen] applicationFrame].size.width;
int scrollViewX = (viewWidth - pageWidth)/2;
// Create the scrollview, setting it to be page size in width the icon height plus padding
CGRect scrollViewFrame = CGRectMake(scrollViewX, 0, pageWidth, pageHeight);
self.scrollModeSelect = [[UIScrollView alloc] initWithFrame:scrollViewFrame];
// Now iterate over the array creating a view for each
// The first view will be offset in X to allow it to be
// centered in the page
int imageOffset = (frameWidth-iconSize)/2;
for (int i = 0; i < [modeSelectIcons count]; ++i) {
// Get the origin x value for the image view within the scroll view
int viewOriginX = i*frameWidth + imageOffset;
// Initialize the image view
UIImageView *ivModeSelect = [[UIImageView alloc]
initWithFrame:CGRectMake(viewOriginX , verticalPadding/2,
iconSize, iconSize)];
// Set the image
ivModeSelect.image = (UIImage *)modeSelectIcons[i];
// Tell the parent view to scale the iamge, preserving aspect ratio, to
// fit the parent view.
ivModeSelect.contentMode = UIViewContentModeScaleAspectFit;
// Add the image view to the scroll view
[self.scrollModeSelect addSubview:ivModeSelect];
}
[self.scrollModeSelect setContentSize:CGSizeMake(contentWidth, pageHeight)];
// Turn off clipping so we can see the adjacent icons
[self.scrollModeSelect setClipsToBounds:FALSE];
// Add the scrollview as a subview
[self addSubview:self.scrollModeSelect];
[self.scrollModeSelect setBackgroundColor:[UIColor blueColor]];
[self setBackgroundColor:[UIColor redColor]];
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect
{
// Drawing code
}
*/
@end
答案 0 :(得分：0)
事实证明，您无法在initWith方法中进行任何视图大小调整，因为尚未确定应用程序框架。因此，要执行此操作，您需要使用默认大小在视图层次结构中设置视图。然后，您需要覆盖layoutSubviews来进行大小调整。在layoutSubviews中，您可以使用self.frame访问视图框。所以这里是与上面相同的代码，但是使用layoutSubviews。
- (void)initView:(CGRect)frame
{
// Initialization code
self.ivModeSelectArray = [[NSMutableArray alloc] init];
// Create an array of images for the different modes
UIImage *imgTowerOnlyMode = [UIImage imageNamed:@"tower_only_mode_icon.png"];
UIImage *imgLocalMode = [UIImage imageNamed:@"local_mode_icon.png"];
UIImage *imgHowToPlay = [UIImage imageNamed:@"how_to_play_icon.png"];
NSArray *modeSelectIcons = @[imgTowerOnlyMode, imgLocalMode, imgHowToPlay];
// Create the scrollview, initially setting it to 0 size. We'll resize it
// in layoutSubviews
CGRect scrollViewFrame = CGRectMake(0,0,200,110);
self.scrollModeSelect = [[UIScrollView alloc] initWithFrame:scrollViewFrame];
// Now iterate over the array creating a view for each, intially set to 0
// size. We'll resize them and reposition them in layoutSubviews
for (int i = 0; i < [modeSelectIcons count]; ++i) {
UIImageView *ivModeSelect =
[self addModeIcon:[modeSelectIcons objectAtIndex:i]];
// Add the image view to the scroll view
[self.scrollModeSelect addSubview:ivModeSelect];
}
// Turn off clipping so we can see the adjacent icons
[self.scrollModeSelect setClipsToBounds:FALSE];
// Turn on paging
[self.scrollModeSelect setPagingEnabled:TRUE];
// Add the scrollview as a subview
[self addSubview:self.scrollModeSelect];
// self.scrollModeSelect.backgroundColor = [UIColor blueColor];
// self.backgroundColor = [UIColor redColor];
}
- (void)layoutSubviews
{
int iconSize = 115;
// Center to center icon spacing
CGFloat viewSpacing = 115 * 1.4;
int frameWidth = viewSpacing;
int contentWidth = 4*frameWidth;
int pageWidth = viewSpacing;
int verticalPadding = 10;
int pageHeight = iconSize + 2*verticalPadding;
int viewWidth = self.frame.size.width;
int scrollViewX = (viewWidth - frameWidth)/2;
// Now iterate over the array configuring the size and offset for each view
// The first view will be offset in X to allow it to be centered in the page
int imageOffset = (frameWidth-iconSize)/2;
for (int i = 0; i < [self.ivModeSelectArray count]; ++i) {
// Get the origin x value for the image view within the scroll view
int viewOriginX = i*viewSpacing + imageOffset;
// Size the image view
UIImageView *ivModeSelect = [self.ivModeSelectArray objectAtIndex:i];
[ivModeSelect setFrame:CGRectMake(viewOriginX , verticalPadding/2,
iconSize, iconSize)];
}
[self.scrollModeSelect setFrame:CGRectMake(scrollViewX, 0,
pageWidth,pageHeight)];
[self.scrollModeSelect setContentSize:CGSizeMake(contentWidth, pageHeight)];
}