今天有个坛友问跳转到文件和图库如何将选择的图片读取出来在Image控件中显示，我这里分享一下解决思路。

首先当然是建个布局页面，页面上放个按钮和图片控件，如下代码

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

<?xml version="1.0" encoding="utf-8"?> <DirectionalLayout     xmlns:ohos="http://schemas.huawei.com/res/ohos"     ohos:height="match_parent"     ohos:width="match_parent"     ohos:orientation="vertical">       <Button         ohos:id="$+id:btnChooseImg"         ohos:height="match_content"         ohos:width="match_content"         ohos:text="选择图片"         ohos:text_size="40vp"         ohos:background_element="gray"></Button>     <Image         ohos:id="$+id:showChooseImg"         ohos:height="match_content"         ohos:width="match_content"         ></Image>   </DirectionalLayout>

然后看一下后台代码，后代主要用到DataAbility去访问图片，访问图片我们需要申请ohos.permission.READ_USER_STORAGE权限，代码如下

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99

package com.example.phonetest.slice;   import com.example.phonetest.ResourceTable; import ohos.aafwk.ability.AbilitySlice; import ohos.aafwk.ability.DataAbilityHelper; import ohos.aafwk.content.Intent; import ohos.aafwk.content.Operation; import ohos.agp.components.Button; import ohos.agp.components.Image; import ohos.hiviewdfx.HiLog; import ohos.hiviewdfx.HiLogLabel; import ohos.media.image.ImageSource; import ohos.media.image.PixelMap; import ohos.media.photokit.metadata.AVStorage; import ohos.utils.net.Uri;   import java.io.File; import java.io.FileDescriptor;   public class ChooseImageTestSlice extends AbilitySlice {     static final HiLogLabel label = new HiLogLabel(HiLog.LOG_APP, 0x0001, "选择图片测试");     private final int imgRequestCode=1123;     Image showChooseImg=null;     @Override     public void onStart(Intent intent) {         super.onStart(intent);         super.setUIContent(ResourceTable.Layout_ability_choose_image_test);         //获取存储权限         requestPermissionsFromUser(new String[]{"ohos.permission.READ_USER_STORAGE"},imgRequestCode);         Button btnChooseImg=(Button)findComponentById(ResourceTable.Id_btnChooseImg);         btnChooseImg.setClickedListener(c->{             //选择图片             selectPic();         });         showChooseImg=(Image)findComponentById(ResourceTable.Id_showChooseImg);     }     private void selectPic() {         Intent intent = new Intent();         Operation opt=new Intent.OperationBuilder().withAction("android.intent.action.GET_CONTENT").build();         intent.setOperation(opt);         intent.addFlags(Intent.FLAG_NOT_OHOS_COMPONENT);         intent.setType("image/*");         startAbilityForResult(intent, imgRequestCode);     }     @Override     protected void onAbilityResult(int requestCode, int resultCode, Intent resultData) {         if(requestCode==imgRequestCode)         {             HiLog.info(label,"选择图片getUriString:"+resultData.getUriString());             //选择的Img对应的Uri             String chooseImgUri=resultData.getUriString();             HiLog.info(label,"选择图片getScheme:"+chooseImgUri.substring(chooseImgUri.lastIndexOf('/')));               //定义数据能力帮助对象             DataAbilityHelper helper=DataAbilityHelper.creator(getContext());             //定义图片来源对象             ImageSource imageSource = null;             //获取选择的Img对应的Id             String chooseImgId=null;             //如果是选择文件则getUriString结果为content://com.android.providers.media.documents/document/image%3A30，其中%3A是":"的URL编码结果，后面的数字就是image对应的Id             //如果选择的是图库则getUriString结果为content://media/external/images/media/30，最后就是image对应的Id             //这里需要判断是选择了文件还是图库             if(chooseImgUri.lastIndexOf("%3A")!=-1){                 chooseImgId = chooseImgUri.substring(chooseImgUri.lastIndexOf("%3A")+3);             }             else {                 chooseImgId = chooseImgUri.substring(chooseImgUri.lastIndexOf('/')+1);             }             //获取图片对应的uri，由于获取到的前缀是content，我们替换成对应的dataability前缀             Uri uri=Uri.appendEncodedPathToUri(AVStorage.Images.Media.EXTERNAL_DATA_ABILITY_URI,chooseImgId);             HiLog.info(label,"选择图片dataability路径:"+uri.toString());             try {                 //读取图片                 FileDescriptor fd = helper.openFile(uri, "r");                 imageSource = ImageSource.create(fd, null);                 //创建位图                 PixelMap pixelMap = imageSource.createPixelmap(null);                 //设置图片控件对应的位图                 showChooseImg.setPixelMap(pixelMap);             } catch (Exception e) {                 e.printStackTrace();             } finally {                 if (imageSource != null) {                     imageSource.release();                 }             }         }     }       @Override     public void onActive() {         super.onActive();     }       @Override     public void onForeground(Intent intent) {         super.onForeground(intent);     } }

这里要注意下在弹出的选择有让我们选择图库还是文件，这两种方式处理方式不一样，判断一下就可以了，代码中已经注释。

我看一下运行结果

记得提前拍两张照片，因为模拟器里面一开始是没有照片的

 

原文链接：https://developer.huawei.com/...
原作者：Kak_zhou