Question

如何在代码中创建图像选择器？

我使用iOS 6.0，使用ARC。

我希望能够选择图片并以某种方式获得所选图像的UIImage。

Answer 1

基本实例化就像这样

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
[imagePicker setDelegate:self];
imagePicker.modalPresentationStyle = UIModalPresentationOverFullScreen;
[self presentViewController:imagePicker animated:YES completion:nil];

有三种获取图像的方法

//Pick from Camera
imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;//Make sure to enable permission for this in info.plist; see: https://stackoverflow.com/a/44690117/2057171

//Pick from all folders in the gallery
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

//Pick from PhotosAlbum(camera roll)
imagePicker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;

然后检查源

的存在

//Check Camera available or not
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])

//Check PhotoLibrary available or not
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) 

//Check front Camera available or not
if ([UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront])

您应该实现委托协议以获取用户选择的图像

//Tells the delegate that the user picked a still image or movie.
 (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
  UIImage *selectedImage = [info objectForKey:UIImagePickerControllerOriginalImage];
  [imagepicker dismissModalViewControllerAnimated:YES];
}

//Tells the delegate that the user cancelled the pick operation.
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
}

使用UIImagePickerController的简单教程

http://www.techotopia.com/index.php/An_Example_iOS_4_iPad_Camera_and_UIImagePickerController_Application_(Xcode_4)

Answer 2

<UIImagePickerControllerDelegate>将代理人添加到@interface ViewController文件中的.h行

如果您打算使用模拟器作为调试器，请确保您的模拟器中有图片然后调用以下方法

- (void)showImagePicker
{
    UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
    imagePicker.delegate = self;
    imagePicker.modalPresentationStyle = UIModalPresentationOverFullScreen;
    [self presentModalViewController:imagePicker animated:YES];
}
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    // Get the selected image.
    UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];

    [picker dismissModalViewControllerAnimated:YES];
}
-(void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
    [picker dismissModalViewControllerAnimated:YES];
}

Answer 3

呈现它：

UIImagePickerController *picker;
picker = [[UIImagePickerController alloc] init];
[picker setDelegate:self];
[picker setSourceType:type];

[self presentViewController:picker animated:YES completion:nil];

获取UIImage：

- (void)imagePickerController:(UIImagePickerController *)thePicker didFinishPickingMediaWithInfo:(NSDictionary *)info
{   
    // Do something with "image"
    UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];

    // users typically expect that if they took a photo it will be saved
    if (thePicker.sourceType == UIImagePickerControllerSourceTypeCamera) {
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
    }

}

如何在代码中制作图像选择器

3 个答案: