提到从摄像头/相册获取图片是面向终端用户的,由用户去浏览并选择图片为程序使用。在这里,我们需要过UIImagePickerController类来和用户交互。 使用UIImagePickerController和用户交互,我们需要实现2个协议<UIImagePickerControllerDelegate,UINavigationControllerDelegate>。 代码如下复制代码 #pragma mark 从用户相册获取活动图片 - (void)pickImageFromAlbum { imagePicker = [[UIImagePickerController alloc] init]; imagePicker.delegate =self; imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary; imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical; imagePicker.allowsEditing =YES; [self presentModalViewController:imagePicker animated:YES]; } 我们来看看上面的从相册获取图片,我们首先要实例化UIImagePickerController对象,然后设置imagePicker对象为当前对象,设置imagePicker的图片来源为UIImagePickerControllerSourceTypePhotoLibrary,表明当前图片的来源为相册,除此之外还可以设置用户对图片是否可编辑。 代码如下复制代码 #pragma mark 从摄像头获取活动图片 - (void)pickImageFromCamera { imagePicker = [[UIImagePickerController alloc] init]; imagePicker.delegate =self; imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera; imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical; imagePicker.allowsEditing =YES; [self presentModalViewController:imagePicker animated:YES]; } //打开相机 - (IBAction)touch_photo:(id)sender { // for iphone UIImagePickerController *pickerImage = [[UIImagePickerController alloc] init]; if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) { pickerImage.sourceType = UIImagePickerControllerSourceTypeCamera; pickerImage.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:pickerImage.sourceType]; } pickerImage.delegate =self; pickerImage.allowsEditing =YES;//自定义照片样式 [self presentViewController:pickerImage animated:YES completion:nil]; } 以上是从摄像头获取图片,和从相册获取图片只是图片来源的设置不一样,摄像头图片的来源为UIImagePickerControllerSourceTypeCamera。 在和用户交互之后,用户选择好图片后,会回调选择结束的方法。 -(void)imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionary*)info { //初始化imageNew为从相机中获得的-- UIImage *imageNew = [info objectForKey:@"UIImagePickerControllerOriginalImage"]; //设置image的尺寸 CGSize imagesize = imageNew.size; imagesize.height =626; imagesize.width =413; //对图片大小进行压缩-- imageNew = [self imageWithImage:imageNew scaledToSize:imagesize]; NSData *imageData = UIImageJPEGRepresentation(imageNew,0.00001); if(m_selectImage==nil) { m_selectImage = [UIImage imageWithData:imageData]; NSLog(@"m_selectImage:%@",m_selectImage); [self.TakePhotoBtn setImage:m_selectImage forState:UIControlStateNormal]; [picker dismissModalViewControllerAnimated:YES]; return ; } [picker release]; } //对图片尺寸进行压缩-- -(UIImage*)imageWithImage:(UIImage*)image scaledToSize:(CGSize)newSize { // Create a graphics image context UIGraphicsBeginImageContext(newSize); // Tell the old image to draw in this new context, with the desired // new size [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)]; // Get the new image from the context UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext(); // End the context UIGraphicsEndImageContext(); // Return the new image. return newImage; }