HarmonyOS鸿蒙Next中资源文件不能使用FileInputStream方式或是ImageSource.create(filedescriptor,null)读取的问题
HarmonyOS鸿蒙Next中资源文件不能使用FileInputStream方式或是ImageSource.create(filedescriptor,null)读取的问题
利用FileInputStream fileInputStream=FileInputStream(FileDescriptor）或是ImageSource.create(FileDescriptor,null)读取resources/media下的图片时，没法读取，是什么原因？利用Resource方法我会的，不用贴Resource方法示范了，谢谢。代码如下：
private FileInputStream fileInputStream;
Resource resource;
private ImageSource imageSource;
private FileDescriptor fileDescriptor;
@Override
public void onStart(Intent intent) {
super.onStart(intent);
super.setUIContent(ResourceTable.Layout_ability_main);
try {
fileDescriptor=getResourceManager().getRawFileEntry(getResourceManager().getMediaPath(ResourceTable.Media_icon)).openRawFileDescriptor().getFileDescriptor();
} catch (IOException e) {
e.printStackTrace();
} catch (NotExistException e) {
e.printStackTrace();
} catch (WrongTypeException e) {
e.printStackTrace();
}
Image image=(Image)findComponentById(ResourceTable.Id_image_show);
imageSource=ImageSource.create(fileDescriptor,null);
image.setPixelMap(imageSource.createPixelmap(null));
}错误如下：
Device info:LIO-AN00Build info:LIO-AN00 2.0.0.218(C00E215R6P6)
Module name:com.example.myapplication8877
Version:1.0.0
Pid:22337
Uid:11444
Foreground:Yes
Reason:crash
Selected stacktrace:
ohos.media.image.SourceDataMalformedException: image decode failed
at ohos.media.image.ImageSource.nativeCreateImageSource(Native Method)
at ohos.media.image.ImageSource.create(ImageSource.java:694)
at com.example.myapplication.slice.MainAbilitySlice.onStart(MainAbilitySlice.java:51)
at ohos.aafwk.ability.AbilitySlice.start(AbilitySlice.java:3270)
at ohos.aafwk.ability.AbilitySliceScheduler.handleStartAbilitySlice(AbilitySliceScheduler.java:717)
at ohos.aafwk.ability.AbilitySliceManager.onAbilityStart(AbilitySliceManager.java:300)
at ohos.aafwk.ability.Ability.dispatchAbilityLifecycle(Ability.java:4579)
at ohos.aafwk.ability.Ability.start(Ability.java:3634)
at ohos.aafwk.ability.Ability.handleLifecycleTransaction(Ability.java:4751)
at ohos.aafwk.ability.Ability.scheduleAbilityLifecycle(Ability.java:1517)
at ohos.abilityshell.AbilityShellDelegate.scheduleAbilityLifecycle(AbilityShellDelegate.java:132)
at ohos.abilityshell.AbilityShellActivityDelegate.onStart(AbilityShellActivityDelegate.java:340)
at ohos.abilityshell.AbilityShellActivity.onStart(AbilityShellActivity.java:67)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1447)
at android.app.Activity.performStart(Activity.java:8237)
at android.app.ActivityThread.handleStartActivity(ActivityThread.java:4084)
at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:235)
at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:215)
at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:187)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:105)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2613)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:219)
at android.app.ActivityThread.main(ActivityThread.java:8668)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:513)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1109)
楼主你好，请参考如下代码：
```java
[@Override](/user/Override)
public void onStart(Intent intent) {
super.onStart(intent);
super.setUIContent(ResourceTable.Layout_ability_main);
Image image=(Image)findComponentById(ResourceTable.Id_image_show);
image.setPixelMap(transId2PixelMap(getContext(), ResourceTable.Media_icon));
}
public static PixelMap transId2PixelMap(Context context, int resId) {
InputStream source = null;
ImageSource imageSource = null;
try {
source = context.getResourceManager().getResource(resId);
imageSource = ImageSource.create(source, null);
ImageSource.DecodingOptions decodingOpts = new ImageSource.DecodingOptions();
decodingOpts.desiredSize = new Size(100, 100);
return imageSource.createPixelmap(decodingOpts);
} catch (IOException | NotExistException e) {
} finally {
try {
source.close();
} catch (IOException e) {
}
}
Optional<PixelMap> optionalEmpty = Optional.empty();
return optionalEmpty.orElse(null);
}更多关于HarmonyOS鸿蒙Next中资源文件不能使用FileInputStream方式或是ImageSource.create(filedescriptor,null)读取的问题的实战系列教程也可以访问 https://www.itying.com/category-93-b0.html
在HarmonyOS鸿蒙Next中，资源文件的读取方式与传统的Android开发有所不同。鸿蒙系统采用了新的资源管理机制，资源文件通常存储在resources目录下，并且通过ResourceManager进行访问。因此，直接使用FileInputStream或ImageSource.create(filedescriptor, null)来读取资源文件可能会导致问题。
鸿蒙系统推荐使用ResourceManager提供的API来访问资源文件。例如，可以通过ResourceManager.getResource方法获取资源的RawFileDescriptor，然后使用ImageSource.create来加载图片资源。具体代码如下：
import resourceManager from '@ohos.resourceManager';
let resourceMgr = resourceManager.getResourceManager();
let rawFileDescriptor = resourceMgr.getRawFileDescriptor('entry/resources/base/media/image.png');
let imageSource = image.createImageSource(rawFileDescriptor.fd, null);对于其他类型的资源文件，如文本文件，可以使用ResourceManager.getRawFileContent方法直接获取文件内容：
let fileContent = resourceMgr.getRawFileContent('entry/resources/base/media/text.txt');这种方式确保了资源文件在鸿蒙系统中的正确访问和管理，避免了直接使用FileInputStream或ImageSource.create(filedescriptor, null)可能带来的兼容性问题。
在HarmonyOS鸿蒙Next中，资源文件的读取方式与传统的Android开发有所不同。由于鸿蒙系统对资源管理进行了优化，直接使用FileInputStream或ImageSource.create(filedescriptor, null)可能会导致读取失败。建议使用鸿蒙提供的ResourceManager API来访问资源文件，例如通过ResourceManager.getResource方法获取资源流。这样可以确保资源文件在鸿蒙系统中被正确加载和使用。
