使用Android相机拍摄图像后的空指针

概述在我的应用程序中,我正在使用 Android设备摄像头捕获图像.对于某些设备,它的工作正常,但有些则不行.我刚刚在LG nexus 4 E960上测试过,在我捕获到我的应用程序崩溃的映像后,无法保存结果. 这是我的代码： //Using intent to open camera Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTUR 在我的应用程序中,我正在使用 Android设备摄像头捕获图像.对于某些设备,它的工作正常,但有些则不行.我刚刚在LG nexus 4 E960上测试过,在我捕获到我的应用程序崩溃的映像后,无法保存结果.
这是我的代码：

//Using intent to open camera  Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);  startActivityForResult(intent,CAMERA_CAPTURE);

在activityResult中：

protected voID onActivityResult(int requestCode,int resultCode,Intent data){    if(resultCode==RESulT_OK)    {        if(requestCode==CAMERA_CAPTURE)        {               Bitmap pictTaken = null ;            Bundle extras = data.getExtras();            if(extras.keySet().contains("data"))            {                pictTaken = (Bitmap) extras.get("data");                picUri = getIntent().getData();            }                    else{                     picUri = getIntent().getData();                try {                    pictTaken = decodeUri(picUri);                } catch (fileNotFoundException e) {                    // Todo auto-generated catch block                    e.printstacktrace();                }                     }            Intent cropIntent= new Intent (this,Crop.class);            cropIntent.putExtra("data",picUri.toString());            cropIntent.putExtra("pict",pictTaken);            cropIntent.putExtra("code","camera");            startActivity(cropIntent);            }        }

捕获并保存它后,该图像显示在下一个活动中,称为Crop.class
这是我的logcat

12-12 13:26:36.340: E/AndroIDRuntime(23575): FATAL EXCEPTION: main 12-12 13:26:36.340: E/AndroIDRuntime(23575): Process: com.example.cobaandroID,PID: 23575 12-12 13:26:36.340: E/AndroIDRuntime(23575): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null,request=1,result=-1,data=Intent { act=inline-data (has extras) }} to activity {com.example.cobaandroID/com.example.cobaandroID.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String androID.net.Uri.toString()' on a null object reference 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.ActivityThread.deliverResults(ActivityThread.java:3368) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.ActivityThread.handleSendResult(ActivityThread.java:3411) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.ActivityThread.access00(ActivityThread.java:138) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.ActivityThread$H.handleMessage(ActivityThread.java:1247) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.os.Handler.dispatchMessage(Handler.java:102) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.os.Looper.loop(Looper.java:136) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.ActivityThread.main(ActivityThread.java:5050) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at java.lang.reflect.Method.invoke(Native Method) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at com.androID.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at com.androID.internal.os.ZygoteInit.main(ZygoteInit.java:595) 12-12 13:26:36.340: E/AndroIDRuntime(23575): Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String androID.net.Uri.toString()' on a null object reference 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at com.example.cobaandroID.MainActivity.onActivityResult(MainActivity.java:226) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.Activity.dispatchActivityResult(Activity.java:5433) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   at androID.app.ActivityThread.deliverResults(ActivityThread.java:3364) 12-12 13:26:36.340: E/AndroIDRuntime(23575):   ... 9 more

我有一个问题要打开/使用在大多数AndroID设备上工作的相机,这个项目的主要目标在很大程度上取决于使用相机.请给我你的帮助,谢谢..

解决方法 尝试下面的代码,

Intent i = new Intent(androID.provIDer.MediaStore.ACTION_IMAGE_CAPTURE);        file file=getoutputMediafile(1);        picUri = Uri.fromfile(file); // create        i.putExtra(MediaStore.EXTRA_OUTPUT,picUri); // set the image file        startActivityForResult(i,CAPTURE_IMAGE);

其中getoutputMediafile(int)将是,

/** Create a file for saving an image */private  file getoutputMediafile(int type){    file mediaStorageDir = new file(Environment.getExternalStoragePublicDirectory(              Environment.DIRECTORY_PICTURES),"MyApplication");    /**Create the storage directory if it does not exist*/    if (! mediaStorageDir.exists()){        if (! mediaStorageDir.mkdirs()){            return null;        }    }    /**Create a media file name*/    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());    file mediafile;    if (type == 1){        mediafile = new file(mediaStorageDir.getPath() + file.separator +        "img_"+ timeStamp + ".png");    } else {        return null;    }    return mediafile;}

最后,

@OverrIDepublic voID onActivityResult(int requestCode,Intent data) {    if (resultCode == Activity.RESulT_OK) {        Intent i;        switch (requestCode) {        case CAPTURE_IMAGE:            //THIS IS YOUR Uri            Uri uri=picUri;             break;        }    }   }

干杯….：)

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