iOS获取相册/相机图片-------自定义获取图片小控件

一、功能简介

1、封装了一个按钮，点击按钮，会提示从何处获取图片：如果设备支持相机，可以从相机获取，同时还可以从手机相册获取图片。

2、选择图片后，有一个block回调，根据需求，将获得的图片拿来使用。

3、提供了初始化方法，可以灵活定义按钮，包括把返回的图片设置给按钮自己。

二、核心原理

1、UIAlertController 提示框

2、UIImagePickerController 图片拾取控制器

3、isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera 类方法，判断是否支持相机

4、遵守UIImagePickerControllerDelegate,UINavigationControllerDelegate

5、实现代理方法获得图片：- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

6、UIImageJPEGRepresentation 方法将图片压缩转换层NSData，然后写入沙盒

三、源码

1、.h文件

@interface ZQImageToolsButton : UIButton

/**
 *  可以获得储存图片信息的字典，里面包含了沙盒里的图片完整路径(程序每次运行沙盒的路径可能会不同，但是图片名不变)
 *
 *  @return
 */
-(NSDictionary * )getImageInfro;

/**
 *  初始化方法，点击按钮可以选择从相册或是相机（如果有相机）选择图片并返回图片
 *
 *  @param title      按钮的名字
 *  @param frame      按钮的frame
 *  @param controller 按钮所在的控制器，弹出对话框的控制器
 *  @param block      获得图片后的回调
 *  @param imageName  储存在沙盒里图片的名字
 *
 *  @return 返回一个按钮
 */
-(instancetype)initWithTitle:(NSString *)title frame:(CGRect)frame controller:(UIViewController *)controller imageBlock:(void(^)(UIImage *))block imageName :(NSString *)imageName;

@end

2、.m文件

@interface ZQImageToolsButton() <UIImagePickerControllerDelegate,UINavigationControllerDelegate>

@property(nonatomic,weak) UIViewController * controller;

@property(nonatomic,copy) void(^imageBlock)(UIImage *) ;

@property(nonatomic,strong) NSString * imageName;

@property(nonatomic,strong) NSDictionary * imageInfro;

@end

@implementation ZQImageToolsButton

-(NSDictionary * )getImageInfro
{
    return self.imageInfro;

}

-(instancetype)initWithTitle:(NSString *)title frame:(CGRect)frame controller:(UIViewController *)controller imageBlock:(void(^)(UIImage *))block imageName :(NSString *)imageName
{

    self = [[ZQImageToolsButton alloc]initWithFrame:frame];

    self.imageBlock = block;

    self.controller = controller;

    self.imageName = imageName;

    [self setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];

    [self setTitle:title forState:UIControlStateNormal];

    [self addTarget:self action:@selector(btnClick:) forControlEvents:UIControlEventTouchUpInside];

    return self ;

}

- (void)btnClick:(UIButton *) btn
{

    // 创建图片管理器、 跳转到相机或相册页面
    UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];

    imagePickerController.delegate = self;

    imagePickerController.allowsEditing = YES;

    //创建弹框

    UIAlertController * av = [UIAlertController alertControllerWithTitle:@"选择" message:@"从您的相册/相机选择" preferredStyle:UIAlertControllerStyleActionSheet];

    //设置image管理器的源类型

    __block NSInteger sourceType = 0;

    UIAlertAction * photo = [UIAlertAction actionWithTitle:@"我的相册" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {

        //图片源为相册

        sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;

        imagePickerController.sourceType = sourceType;

        [self.controller presentViewController:imagePickerController animated:YES completion:^{}];

    }];

    UIAlertAction * camera = [UIAlertAction actionWithTitle:@"我的相机" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {

        //图片源为相机

        sourceType = UIImagePickerControllerSourceTypeCamera;

        imagePickerController.sourceType = sourceType;

        [self.controller presentViewController:imagePickerController animated:YES completion:^{}];

    }];

    UIAlertAction * cancle = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
        //取消
    }];

    //判断是否支持相机

    if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
    {
        [av addAction:photo];
        [av addAction:camera];
        [av addAction:cancle];

    }
    else
    {
        //如果不支持相机，就不用把相机按钮加入提示框了
        [av addAction:photo];
        [av addAction:cancle];
    }

    [self.controller presentViewController:av animated:YES completion:nil];

}

// 图片选择结束之后，走这个方法，字典存放所有图片信息
#pragma mark - image picker delegte 系统代理，返回从相册中选中的图片
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    [picker dismissViewControllerAnimated:YES completion:^{

        NSLog(@"选好图片了");

    }];

    //获得选中的图片了！
    UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];

    //block回调，获得图片后，交给控制器
    self.imageBlock(image);

    // 保存图片至本地，用传进来的名字重新拼接图片名字

    NSString * imgName = [NSString stringWithFormat:@"SavedImage-%@.png",self.imageName];

    //拼接保存至沙盒的路径
    NSString *fullPath = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:imgName];

    //记录一下图片的信息，存到字典中，需要的时候可以访问
    NSDictionary *dic = @{@"image":fullPath};
    self.imageInfro = dic;

    //保存到沙盒

    [self saveImage:image withName:imgName filePath:fullPath];

}

//保存至沙盒
- (void) saveImage:(UIImage *)currentImage withName:(NSString *)imageName filePath:(NSString *)filePath
{
    //压缩比例0.5
    NSData * imageData = UIImageJPEGRepresentation(currentImage, 0.5);

    // 将图片写入文件
    [imageData writeToFile:filePath atomically:NO];
}

@end

四、扩展

1、本例没有实现图片的多选

2、本例没有实现上传图片的业务逻辑

3、小东西，供娱乐交流使用