On iPad, UIImagePickerController must be presented via UIPopoverController

<code><span class="kwd"><span style="font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; ">On iPad, UIImagePickerController must be presented via UIPopoverController  可以用以下方法来判断设备的类型选择不同的Controller</span></span></code>

<code><span class="kwd">if</span><span class="pln"> </span><span class="pun">(</span><span class="pln">UI_USER_INTERFACE_IDIOM</span><span class="pun">()</span><span class="pln"> </span><span class="pun">==</span><span class="pln"> </span><span class="typ">UIUserInterfaceIdiomPhone</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
</span><span class="com">// We are using an iPhone</span><span class="pln">
</span><span class="typ">UIActionSheet</span><span class="pln"> </span><span class="pun">*</span><span class="pln">alertSheet </span><span class="pun">=</span><span class="pln"> </span><span class="pun">[[</span><span class="typ">UIActionSheet</span><span class="pln"> alloc</span><span class="pun">]</span><span class="pln"> initWithTitle</span><span class="pun">:@</span><span class="str">"Where do you want to get your daily image?"</span><span class="pln"> delegate</span><span class="pun">:(</span><span class="pln">self</span><span class="pun">)</span><span class="pln"> cancelButtonTitle</span><span class="pun">:@</span><span class="str">"Cancel"</span><span class="pln"> destructiveButtonTitle</span><span class="pun">:</span><span class="pln">nil otherButtonTitles</span><span class="pun">:@</span><span class="str">"Camera"</span><span class="pun">,</span><span class="pln"> </span><span class="pun">@</span><span class="str">"Library"</span><span class="pun">,</span><span class="pln"> nil</span><span class="pun">];</span><span class="pln">
</span><span class="pun">[</span><span class="pln">alertSheet setTag</span><span class="pun">:</span><span class="lit">0</span><span class="pun">];</span><span class="pln">
</span><span class="pun">[</span><span class="pln">alertSheet setDelegate</span><span class="pun">:</span><span class="pln">self</span><span class="pun">];</span><span class="pln">
</span><span class="pun">[</span><span class="pln">alertSheet showFromTabBar</span><span class="pun">:[[</span><span class="pln">self tabBarController</span><span class="pun">]</span><span class="pln"> tabBar</span><span class="pun">]];</span><span class="pln">
</span><span class="pun">[</span><span class="pln">alertSheet release</span><span class="pun">];</span><span class="pln">
</span><span class="pun">}</span><span class="kwd">else</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
</span><span class="com">// We are using an iPad</span><span class="pln">
</span><span class="typ">UIImagePickerController</span><span class="pln"> </span><span class="pun">*</span><span class="pln">imagePickerController </span><span class="pun">=</span><span class="pln"> </span><span class="pun">[[</span><span class="typ">UIImagePickerController</span><span class="pln"> alloc</span><span class="pun">]</span><span class="pln"> init</span><span class="pun">];</span><span class="pln">
imagePickerController</span><span class="pun">.</span><span class="pln">delegate </span><span class="pun">=</span><span class="pln"> self</span><span class="pun">;</span><span class="pln">
</span><span class="typ">UIPopoverController</span><span class="pln"> </span><span class="pun">*</span><span class="pln">popoverController</span><span class="pun">=[[</span><span class="typ">UIPopoverController</span><span class="pln"> alloc</span><span class="pun">]</span><span class="pln"> initWithContentViewController</span><span class="pun">:</span><span class="pln">imagePickerController</span><span class="pun">];</span><span class="pln">
popoverController</span><span class="pun">.</span><span class="pln">delegate</span><span class="pun">=</span><span class="pln">self</span><span class="pun">;</span><span class="pln">
</span><span class="pun">[</span><span class="pln">popoverController presentPopoverFromRect</span><span class="pun">:((</span><span class="typ">UIButton</span><span class="pln"> </span><span class="pun">*)</span><span class="pln">sender</span><span class="pun">).</span><span class="pln">bounds inView</span><span class="pun">:</span><span class="pln">sender permittedArrowDirections</span><span class="pun">:</span><span class="typ">UIPopoverArrowDirectionAny</span><span class="pln"> animated</span><span class="pun">:</span><span class="pln">YES</span><span class="pun">];</span><span class="pln">
</span><span class="pun">}</span></code>

<code><span class="pun">
</span></code>

<code><span class="pun"></span></code><p style="margin-top: 10px; margin-bottom: 10px; padding-top: 0px; padding-bottom: 0px; background-color: rgb(248, 248, 248); text-indent: 28px; font-family: 宋体; line-height: 28px; "><span style="text-align: center; ">iPad</span>与<span style="text-align: center; ">iPhone</span>调用<span style="text-align: center; ">UIImagePickerViewController</span>方法略有不同是本文要介绍的内容，文中很详细的讲述了<span style="text-align: center; ">iPad</span>与<span style="text-align: center; ">iphone</span>各自的调用方法，来看详细内容。</p><p style="margin-top: 10px; margin-bottom: 10px; padding-top: 0px; padding-bottom: 0px; background-color: rgb(248, 248, 248); text-indent: 28px; font-family: 宋体; line-height: 28px; ">我们知道，在<span style="text-align: center; ">iPhone</span>中获取照片库常用的方法如下：</p><pre style="white-space: pre-wrap; word-wrap: break-word; margin-top: 0px; margin-bottom: 1em; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; font-family: 'Courier New', monospace; width: 591.0166625976563px; overflow-x: auto; overflow-y: auto; background-color: rgb(230, 230, 230); line-height: 28px; "><ol class="dp-xml" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 1px !important; margin-left: 55px; padding-top: 5px; padding-right: 0px; padding-bottom: 5px; padding-left: 0px; color: rgb(92, 92, 92); list-style-position: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: rgb(247, 247, 247); "><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">UIImagePickerController *</span><span class="attribute" style="color: red; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">m_imagePicker</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; "> = [[UIImagePickerController alloc] init];  </span></span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">    if ([UIImagePickerController isSourceTypeAvailable:  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">         UIImagePickerControllerSourceTypePhotoLibrary]) {  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        </span><span class="attribute" style="color: red; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">m_imagePicker.sourceType</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; "> = </span><span class="attribute-value" style="color: blue; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">UIImagePickerControllerSourceTypePhotoLibrary</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">;  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        </span><span class="attribute" style="color: red; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">m_imagePicker.delegate</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; "> = </span><span class="attribute-value" style="color: blue; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">self</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">;  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        //        [m_imagePicker.navigationBar.subviews];  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        [m_imagePicker setAllowsEditing:NO];  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        //</span><span class="attribute" style="color: red; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">m_imagePicker.allowsImageEditing</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; "> = </span><span class="attribute-value" style="color: blue; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">NO</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">;  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        [self presentModalViewController:m_imagePicker animated:YES];  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        [m_imagePicker release];  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">    }else {  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        UIAlertView *</span><span class="attribute" style="color: red; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: inherit; ">alert</span><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; "> = [[UIAlertView alloc]initWithTitle:nil message:  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">@"Error accessing photo library!" delegate:nil cancelButtonTitle:@"Close" otherButtonTitles:nil];  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        [alert show];  </span></li><li class="alt" style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; color: inherit; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">        [alert release];  </span></li><li style="margin-top: 0px !important; margin-right: 0px !important; margin-bottom: 0px !important; margin-left: 0px !important; padding-top: 0px !important; padding-right: 3px !important; padding-bottom: 0px !important; padding-left: 10px !important; list-style-type: none; list-style-position: initial; list-style-image: initial; word-wrap: break-word; word-break: normal; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; background-color: transparent; line-height: 18px; "><span style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; border-top-style: none; border-right-style: none; border-bottom-style: none; border-left-style: none; border-width: initial; border-color: initial; border-image: initial; color: black; background-color: inherit; ">    } </span></li></ol>

这对iPhone的操作是没有问题的。但是当我们在iPad环境中却有问题了，当我们运行时会报如下错误：

Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: 'On iPad, UIImagePickerController must be presented via UIPopoverController'

所以我们必须通过UIPopoverController来实现才行。具体实现如下：

UIImagePickerController *m_imagePicker = [[UIImagePickerController alloc] init];
if ([UIImagePickerController isSourceTypeAvailable:
UIImagePickerControllerSourceTypePhotoLibrary]) {
m_imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
m_imagePicker.delegate = self;
[m_imagePicker setAllowsEditing:NO];
UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:m_imagePicker];
self.popoverController = popover;
//popoverController.delegate = self;

[popoverController presentPopoverFromRect:CGRectMake(0, 0, 300, 300) inView:self.
view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

//[self presentModalViewController:m_imagePicker animated:YES];
[popover release];
[m_imagePicker release];
}else {
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"Error accessing photo library!"
delegate:nil cancelButtonTitle:@"Close" otherButtonTitles:nil];
[alert show];
[alert release];
}

这里需要注意，对局部UIPopoverController对象popover我们赋给了一个全局的UIPopoverController对象popoverController。而不能直接调用popover。因为在popover对象还可见时，是不能够被释放的。

小结：iPad与iphone调用UIImagePickerViewController方法略有不同的内容介绍完了，希望本文对你有所帮助！