Question

我正在开发一个电子书阅读器（就像ibook一样），因为我需要在iPhone上点击图像来控制背景的屏幕亮度。我这样做了。

background.m

-(void)brightness
{
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    UIImage *image = [UIImage imageNamed:@"brightness.jpg"];
    button.frame = CGRectMake(0, 0, image.size.width, image.size.height);
    [button setImage:image forState:UIControlStateNormal];

    UIButton *button1 = [UIButton buttonWithType:UIButtonTypeCustom];
    UIImage *image1 = [UIImage imageNamed:@"brightness.jpg"];
    button1.frame = CGRectMake(0, 0, image1.size.width, image1.size.height);
    [button1 setImage:image forState:UIControlStateNormal];
    [button1 addTarget:self action:@selector(brightnessControl:) forControlEvents:UIControlEventTouchUpInside];

    gBrightnessSetting=100;

    brightnessOverlay = [[CALayer alloc] init];
    brightnessOverlay.masksToBounds = YES;
    brightnessOverlay.backgroundColor = [[[UIColor blackColor] colorWithAlphaComponent:1.0] CGColor];
    brightnessOverlay.opacity = 0.0;
    [self.layer addSublayer:brightnessOverlay];

    bottomButtonsSize = SCREENWIDTH/5;

}

- (void)dealloc {
    [brightnessLessButton release];
    [brightnessMoreButton release];

    [super dealloc];
}
- (void) setLayerFrames {
    brightnessOverlay.frame = CGRectMake(self.layer.bounds.origin.x,self.layer.bounds.origin.y,self.bounds.size.width,self.layer.bounds.size.height);
}

-(void)brightnessControl:(id)sender
 {  
    if(brightnessOverlay.opacity <= 0.05) {
    }else{
        double newBrightness = (brightnessOverlay.opacity-0.15);
        brightnessOverlay.opacity = newBrightness;
        NSLog(@"BRIGHTNESS FLOAT %f",brightnessOverlay.opacity);
        gBrightnessSetting=100-(int)(newBrightness*100);
        NSLog(@"BRIGHTNESS Value %d%%",gBrightnessSetting);
    }

}

我正在电子书中调用dis，像这样，

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

   if ([indexPath row]==0) {
       background *back=[[background alloc] init];
       [back brightness];

       [self.view addSubview:back];

    }
}

我的代码有什么问题...当我按下亮度选项时我的应用程序崩溃了。有什么建议。

Answer 1

iOS 5.0，你可以使用[[UIScreen mainScreen] setBrightness：1.0];

Answer 2

很明显，没有公共API可以做到这一点。

这样做的一种方式（可能不是更好的方法）是更改应用中视图，文本的颜色在调光器和更亮的颜色之间。

Answer 3

没有Apple记录的实现屏幕亮度控制的方法！

Answer 4

使用调试器并找出导致崩溃的代码行。

Answer 5

有私人API调用，但如果您使用它，肯定会被拒绝

GSEventSetBacklightLevel(0.5f);

屏幕亮度控制

5 个答案: