Android 调用相机出现异常 NullPointerException: uri

水深无声 2023-07-04 15:44 2阅读 0赞

碰到个很玄学的问题，今天项目需要调用摄像头，由于之前使用过，直接从原有项目copy了。

#### 异常信息 ####

java.lang.RuntimeException: Unable to resume activity {
        com.example.androidx/com.example.androidx.activity.FaceDatabaseManage}: java.lang.RuntimeException: Failure delivering result ResultInfo{
        who=null, request=1, result=-1, data=null} to activity {
        com.example.androidx/com.example.androidx.activity.FaceDatabaseManage}: java.lang.NullPointerException: uri
            at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4430)
            at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4470)
            at android.app.servertransaction.ResumeActivityItem.execute(ResumeActivityItem.java:51)
            at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:145)
            at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2199)
            at android.os.Handler.dispatchMessage(Handler.java:112)
            at android.os.Looper.loop(Looper.java:216)
            at android.app.ActivityThread.main(ActivityThread.java:7625)
            at java.lang.reflect.Method.invoke(Native Method)
            at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:987)
         Caused by: java.lang.RuntimeException: Failure delivering result ResultInfo{
        who=null, request=1, result=-1, data=null} to activity {
        com.example.androidx/com.example.androidx.activity.FaceDatabaseManage}: java.lang.NullPointerException: uri
            at android.app.ActivityThread.deliverResults(ActivityThread.java:5078)
            at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4409)
            at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4470) 
            at android.app.servertransaction.ResumeActivityItem.execute(ResumeActivityItem.java:51) 
            at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:145) 
            at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70) 
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2199) 
            at android.os.Handler.dispatchMessage(Handler.java:112) 
            at android.os.Looper.loop(Looper.java:216) 
            at android.app.ActivityThread.main(ActivityThread.java:7625) 
            at java.lang.reflect.Method.invoke(Native Method) 
            at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524) 
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:987) 
         Caused by: java.lang.NullPointerException: uri
            at com.android.internal.util.Preconditions.checkNotNull(Preconditions.java:128)
            at android.content.ContentResolver.openInputStream(ContentResolver.java:1016)
            at com.example.androidx.activity.FaceDatabaseManage.onActivityResult(FaceDatabaseManage.java:246)
            at android.app.Activity.dispatchActivityResult(Activity.java:7797)
            at android.app.ActivityThread.deliverResults(ActivityThread.java:5071)
            at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4409) 
            at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4470) 
            at android.app.servertransaction.ResumeActivityItem.execute(ResumeActivityItem.java:51) 
            at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:145) 
            at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70) 
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2199) 
            at android.os.Handler.dispatchMessage(Handler.java:112) 
            at android.os.Looper.loop(Looper.java:216) 
            at android.app.ActivityThread.main(ActivityThread.java:7625) 
            at java.lang.reflect.Method.invoke(Native Method) 
            at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524) 
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:987)

#### 代码相关 ####

调用相机的代码

private void startCamaraForRegister() {
        
            // 创建File对象，用于存储拍照后的图片
            File outputImage = new File(getExternalCacheDir(), "output_image.jpg");
            try {
        
                if (outputImage.exists()) {
        
                    outputImage.delete();
                }
                outputImage.createNewFile();
            } catch (IOException e) {
        
                e.printStackTrace();
            }
    
            if (Build.VERSION.SDK_INT < 24) {
        
                imageUri = Uri.fromFile(outputImage);
            } else {
        
                imageUri = FileProvider.getUriForFile(FaceDatabaseManage.this, AUTHORITY, outputImage);
    
            }
            // 启动相机程序
            Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
            System.out.println(imageUri==null);
            intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
            startActivityForResult(intent, TAKE_PHOTO);
    
        }

在这里我打印了imageUri，这里显示不是空，从而执行 `startActivityForResult`方法

@Override
        public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        
            System.out.println(imageUri==null);
            System.out.println("11111111");
    
            switch (requestCode) {
        
                case TAKE_PHOTO:
                    if (resultCode == RESULT_OK) {
        
                        try {
        
                            //将拍摄的照片显示到头像中
                            Bitmap bitmap = BitmapFactory.decodeStream(FaceDatabaseManage.this.getContentResolver().openInputStream(imageUri));
                          
                        } catch (FileNotFoundException e) {
        
                            e.printStackTrace();
                        }
                    }
                    break;
              
                default:
                    break;
            }
        }

竟然提示imageUri是空的，明明我们先获取了imageUri ，并且打印显示不是空的，**难道我的全局变量改变了？**  
更玄学的是，横屏报错，正常竖屏就没问题!!! 于是我就去stackflow上逛了半天

碰见一个跟我一样的问题  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzg4OTg0MQ_size_16_color_FFFFFF_t_70]  
[https://stackoverflow.com/questions/20424909/android-startcamera-gives-me-null-intent-and-does-it-destroy-my-global-varia][https_stackoverflow.com_questions_20424909_android-startcamera-gives-me-null-intent-and-does-it-destroy-my-global-varia]

#### 解决方案: ####

imanfest文件中，在对应的activity 加

android:windowSoftInputMode="adjustResize"  
    android:configChanges="orientation|keyboardHidden|screenSize"

解决

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzg4OTg0MQ_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200212163028159.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzg4OTg0MQ==,size_16,color_FFFFFF,t_70
[https_stackoverflow.com_questions_20424909_android-startcamera-gives-me-null-intent-and-does-it-destroy-my-global-varia]: https://stackoverflow.com/questions/20424909/android-startcamera-gives-me-null-intent-and-does-it-destroy-my-global-varia