使用 Android 模拟器捕获和保存图像时出现空指针异常

我正在尝试通过 Android 模拟器捕获并保存图像，正在捕获图像，但保存的文件已损坏。

可能是什么原因造成的？谁能帮我找出可能的错误点？

下面是我的代码：

**public void onCreate**(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    **Intent** intent = new **Intent**("android.media.action.IMAGE_CAPTURE");
    try {
        fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
    } 

    catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    intent.putExtra(**MediaStore**.EXTRA_OUTPUT, fileUri);
    startActivityForResult(intent, CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE);
}

@Override
**protected void onActivityResult**(int requestCode, int resultCode, Intent data) {
    if (requestCode == CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE) {
        if (resultCode == RESULT_OK) {
            StoreImage(this, data.getData(),
            mediaFile);
            finish();
        } 

        else if (resultCode == RESULT_CANCELED) {
            // User cancelled the image capture
        } 

        else {
            finish();
            try {
            } 

            catch (Exception e) {
               e.printStackTrace();
            }
        }
    }

}

堆栈跟踪如下：

04-05 23:55:40.369: E/AndroidRuntime(534): FATAL EXCEPTION: main
04-05 23:55:40.369: E/AndroidRuntime(534): java.lang.RuntimeException: Unable to start activity ComponentInfo{camera.android/camera.android.CameraActivity}: java.lang.NullPointerException: file
04-05 23:55:40.369: E/AndroidRuntime(534):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1955)

04-05 23:55:40.369: E/AndroidRuntime(534): Caused by: java.lang.NullPointerException: file
04-05 23:55:40.369: E/AndroidRuntime(534):  at android.net.Uri.fromFile(Uri.java:441)
04-05 23:55:40.369: E/AndroidRuntime(534):  at camera.android.CameraActivity.getOutputMediaFileUri(CameraActivity.java:72)
04-05 23:55:40.369: E/AndroidRuntime(534):  at camera.android.CameraActivity.onCreate(CameraActivity.java:34)
04-05 23:55:40.369: E/AndroidRuntime(534):  at android.app.Activity.performCreate(Activity.java:4465)
04-05 23:55:40.369: E/AndroidRuntime(534):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
04-05 23:55:40.369: E/AndroidRuntime(534):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1919)

检查您是否在清单文件中添加了以下权限::

<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.CAMERA" />

也在

fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);

我认为你也必须附加你想要保存的文件名，只给出路径是不够的......