iphone 怎么使用图片选取器 UIImagePickerController

                                                            iphone 怎么使用图片选取器 

1。 定义 类变量：

       UIImagePickerController* picker_library_;

 

 

2。实现 UIImagePickerControllerDelegate   这个delegate

 

 

3。 以模态的方式，显示 图片选取器

      picker_library_ = [[UIImagePickerController alloc] init];picker_library_.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;picker_library_.allowsEditing = YES;picker_camera_.allowsImageEditing=YES;picker_library_.delegate = self;[self presentModalViewController: picker_library_animated: YES]; 

      其中，sourceType 指定了 几种 图片的来源：

      UIImagePickerControllerSourceTypePhotoLibrary：表示显示所有的照片

      UIImagePickerControllerSourceTypeCamera：表示从摄像头选取照片

      UIImagePickerControllerSourceTypeSavedPhotosAlbum：表示仅仅从相册中选取照片。

 

      allowEditing和allowsImageEditing  设置为YES，表示 允许用户编辑图片，否则，不允许用户编辑。

 

 

4。 当用户选择一个图片以后，有可能调用两种不同的函数，根据版本的不同。所以，如果要同时支持高版本和低版本的兼容性，那么就

      要处理两种函数。

 

      //3.x  用户选中图片后的回调

- (void)imagePickerController: (UIImagePickerController *)picker 

didFinishPickingMediaWithInfo: (NSDictionary *)info

 

 

     //2.x  用户选中图片之后的回调

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo

 

 

     两种函数的处理代码如下：

     //3.x 用户选中图片后的回调- (void)imagePickerController: (UIImagePickerController *)picker didFinishPickingMediaWithInfo: (NSDictionary *)info{if (picker == picker_camera_) {//如果是 来自照相机的image，那么先保存UIImage* original_image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];UIImageWriteToSavedPhotosAlbum(original_image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);}//获得编辑过的图片UIImage* image = [info objectForKey: @"UIImagePickerControllerEditedImage"];[self dismissModalViewControllerAnimated:YES];[picker release];} 

      //2.x 用户选中图片之后的回调- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo{NSMutableDictionary * dict= [NSMutableDictionary dictionaryWithDictionary:editingInfo];[dict setObject:image forKey:@"UIImagePickerControllerEditedImage"];//直接调用3.x的处理函数[self imagePickerController:picker didFinishPickingMediaWithInfo:dict];} 

 

 

  5。 用户取消选择

      // 用户选择取消- (void) imagePickerControllerDidCancel: (UIImagePickerController *)picker{[self dismissModalViewControllerAnimated:YES];[picker release];}