问题
Is there an apple-house-made way to get a UISlider with a ProgressView. This is used by many streaming applications e.g. native quicktimeplayer or youtube. (Just to be sure: i'm only in the visualization interested)
cheers Simon
回答1:
Here's a simple version of what you're describing.
It is "simple" in the sense that I didn't bother trying to add the shading and other subtleties. But it's easy to construct and you can tweak it to draw in a more subtle way if you like. For example, you could make your own image and use it as the slider's thumb.
This is actually a UISlider subclass lying on top of a UIView subclass (MyTherm) that draws the thermometer, plus two UILabels that draw the numbers.
The UISlider subclass eliminates the built-in track, so that the thermometer behind it shows through. But the UISlider's thumb (knob) is still draggable in the normal way, and you can set it to a custom image, get the Value Changed event when the user drags it, and so on. Here is the code for the UISlider subclass that eliminates its own track:
- (CGRect)trackRectForBounds:(CGRect)bounds {
CGRect result = [super trackRectForBounds:bounds];
result.size.height = 0;
return result;
}
The thermometer is an instance of a custom UIView subclass, MyTherm. I instantiated it in the nib and unchecked its Opaque and gave it a background color of Clear Color. It has a value property so it knows how much to fill the thermometer. Here's its drawRect: code:
- (void)drawRect:(CGRect)rect {
CGContextRef c = UIGraphicsGetCurrentContext();
[[UIColor whiteColor] set];
CGFloat ins = 2.0;
CGRect r = CGRectInset(self.bounds, ins, ins);
CGFloat radius = r.size.height / 2.0;
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, CGRectGetMaxX(r) - radius, ins);
CGPathAddArc(path, NULL, radius+ins, radius+ins, radius, -M_PI/2.0, M_PI/2.0, true);
CGPathAddArc(path, NULL, CGRectGetMaxX(r) - radius, radius+ins, radius, M_PI/2.0, -M_PI/2.0, true);
CGPathCloseSubpath(path);
CGContextAddPath(c, path);
CGContextSetLineWidth(c, 2);
CGContextStrokePath(c);
CGContextAddPath(c, path);
CGContextClip(c);
CGContextFillRect(c, CGRectMake(r.origin.x, r.origin.y, r.size.width * self.value, r.size.height));
}
To change the thermometer value, change the MyTherm instance's value to a number between 0 and 1, and tell it to redraw itself with setNeedsDisplay.
回答2:
This is doable using the standard controls.
In Interface Builder place your UISlider immediately on top of your UIProgressView and make them the same size.
On a UISlider the background horizontal line is called the track, the trick is to make it invisible. We do this with a transparent PNG and the UISlider methods setMinimumTrackImage:forState: and setMaximumTrackImage:forState:.
In the viewDidLoad method of your view controller add:
[self.slider setMinimumTrackImage:[UIImage imageNamed:@"transparent.png"] forState:UIControlStateNormal];
[self.slider setMaximumTrackImage:[UIImage imageNamed:@"transparent.png"] forState:UIControlStateNormal];
where self.slider refers to your UISlider.
I've tested the code in Xcode, and this will give you a slider with an independent progress bar.
回答3:
Solution that suits my design:
class SliderBuffering:UISlider {
let bufferProgress = UIProgressView(progressViewStyle: .Default)
override init (frame : CGRect) {
super.init(frame : frame)
}
convenience init () {
self.init(frame:CGRect.zero)
setup()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
func setup() {
self.minimumTrackTintColor = UIColor.clearColor()
self.maximumTrackTintColor = UIColor.clearColor()
bufferProgress.backgroundColor = UIColor.clearColor()
bufferProgress.userInteractionEnabled = false
bufferProgress.progress = 0.0
bufferProgress.progressTintColor = UIColor.lightGrayColor().colorWithAlphaComponent(0.5)
bufferProgress.trackTintColor = UIColor.blackColor().colorWithAlphaComponent(0.5)
self.addSubview(bufferProgress)
}
}
回答4:
Create a UISlider:
// 1
// Make the slider as a public propriety so you can access it
playerSlider = [[UISlider alloc] init];
[playerSlider setContinuous:YES];
[playerSlider setHighlighted:YES];
// remove the slider filling default blue color
[playerSlider setMaximumTrackTintColor:[UIColor clearColor]];
[playerSlider setMinimumTrackTintColor:[UIColor clearColor]];
// Chose your frame
playerSlider.frame = CGRectMake(--- , -- , yourSliderWith , ----);
// 2
// create a UIView that u can access and make it the shadow of your slider
shadowSlider = [[UIView alloc] init];
shadowSlider.backgroundColor = [UIColor lightTextColor];
shadowSlider.frame = CGRectMake(playerSlider.frame.origin.x , playerSlider.frame.origin.y , playerSlider.frame.size.width , playerSlider.frame.origin.size.height);
shadowSlider.layer.cornerRadius = 4;
shadowSlider.layer.masksToBounds = YES;
[playerSlider addSubview:shadowSlider];
[playerSlider sendSubviewToBack:shadowSlider];
// 3
// Add a timer Update your slider and shadow slider programatically
[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(updateSlider) userInfo:nil repeats:YES];
-(void)updateSlider {
// Update the slider about the music time
playerSlider.value = audioPlayer.currentTime; // based on ur case
playerSlider.maximumValue = audioPlayer.duration;
float smartWidth = 0.0;
smartWidth = (yourSliderFullWidth * audioPlayer.duration ) / 100;
shadowSlider.frame = CGRectMake( shadowSlider.frame.origin.x , shadowSlider.frame.origin.y , smartWidth , shadowSlider.frame.size.height);
}
Enjoy! P.S. I might have some typos.
回答5:
Idea 1: You could easily use the UISlider as a progress view by subclassing it. It responds to methods such as 'setValue:animated:' with which you can set the value (i.e: progress) of the view.
Your only 'restriction' creating what you see in your example is the buffer bar, which you could create by 'creatively' skinning the UISlider (because you can add custom skins to it), and perhaps set that skin programmatically.
Idea 2: Another (easier) option is to subclass UIProgressView, and create a UISlider inside that subclass. You can skin the UISlider to have a see-through skin (no bar, just the knob visible) and lay it over the UIProgressView.
You can use the UIProgressView for the pre-loading (buffering) and the UISlider for movie control / progress indication.
Seems fairly easy :-)
Edit: to actually answer your question, there is no in-house way, but it would be easy to accomplish with the tools given.
回答6:
You can do some trick like this, it's more easy and understanding. Just insert the code bellow in your UISlider subclass.
- (void)layoutSubviews
{
[super layoutSubviews];
if (_availableDurationImageView == nil) {
// step 1
// get max length that our "availableDurationImageView" will show
UIView *maxTrackView = [self.subviews objectAtIndex:self.subviews.count - 3];
UIImageView *maxTrackImageView = [maxTrackView.subviews objectAtIndex:0];
_maxLength = maxTrackImageView.width;
// step 2
// get the right frame where our "availableDurationImageView" will place in superView
UIView *minTrackView = [self.subviews objectAtIndex:self.subviews.count - 2];
_availableDurationImageView = [[UIImageView alloc] initWithImage:[[UIImage imageNamed:@"MediaSlider.bundle/4_jindu_huancun.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 2, 0, 2)]];
_availableDurationImageView.opaque = NO;
_availableDurationImageView.frame = minTrackView.frame;
[self insertSubview:_availableDurationImageView belowSubview:minTrackView];
}
}
- (void)setAvailableValue:(NSTimeInterval)availableValue
{
if (availableValue >=0 && availableValue <= 1) {
// use "maxLength" and percentage to set our "availableDurationImageView" 's length
_availableDurationImageView.width = _maxLength * availableValue;
}
}
回答7:
Adding on matt's solution, note that as of iOS 7.0, implementing trackRectForBounds: is rendered impossible. Here is my solution to this problem :
In your UISlider subclass, do this :
-(void)awakeFromNib
{
[super awakeFromNib];
UIImage* clearColorImage = [UIImage imageWithColor:[UIColor clearColor]];
[self setMinimumTrackImage:clearColorImage forState:UIControlStateNormal];
[self setMaximumTrackImage:clearColorImage forState:UIControlStateNormal];
}
with imageWithColor as this function :
+ (UIImage*) imageWithColor:(UIColor*)color
{
return [UIImage imageWithColor:color andSize:CGSizeMake(1.0f, 1.0f)];
}
That will properly take care of this annoying trackRectangle.
I spent too much time looking for a solution to this problem, here's hoping that'll save some time to another poor soul ;).
回答8:
Here is a solution in Objective C. https://github.com/abhimuralidharan/BufferSlider
The idea is to create a UIProgressview as a property in the UISlider subclass and add the required constraints programatically.
#import <UIKit/UIKit.h> //.h file
@interface BufferSlider : UISlider
@property(strong,nonatomic) UIProgressView *bufferProgress;
@end
#import "BufferSlider.h" //.m file
@implementation BufferSlider
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self setup];
}
return self;
}
-(void)setup {
self.bufferProgress = [[UIProgressView alloc] initWithFrame:self.bounds];
self.minimumTrackTintColor = [UIColor redColor];
self.maximumTrackTintColor = [UIColor clearColor];
self.value = 0.2;
self.bufferProgress.backgroundColor = [UIColor clearColor];
self.bufferProgress.userInteractionEnabled = NO;
self.bufferProgress.progress = 0.7;
self.bufferProgress.progressTintColor = [[UIColor blueColor] colorWithAlphaComponent:0.5];
self.bufferProgress.trackTintColor = [[UIColor lightGrayColor] colorWithAlphaComponent:2];
[self addSubview:self.bufferProgress];
[self setThumbImage:[UIImage imageNamed:@"redThumb"] forState:UIControlStateNormal];
self.bufferProgress.translatesAutoresizingMaskIntoConstraints = NO;
NSLayoutConstraint *left = [NSLayoutConstraint constraintWithItem:self.bufferProgress attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeLeft multiplier:1 constant:0];
NSLayoutConstraint *centerY = [NSLayoutConstraint constraintWithItem:self.bufferProgress attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeCenterY multiplier:1 constant:0.75]; // edit the constant value based on the thumb image
NSLayoutConstraint *right = [NSLayoutConstraint constraintWithItem:self.bufferProgress attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeTrailing multiplier:1 constant:0];
[self addConstraints:@[left,right,centerY]];
[self sendSubviewToBack:self.bufferProgress];
}
- (instancetype)initWithCoder:(NSCoder *)coder
{
self = [super initWithCoder:coder];
if (self) {
[self setup];
}
return self;
}
@end
来源：https://stackoverflow.com/questions/4495433/uislider-with-progressview-combined