我正在制作一个应用程序来捕获图像一次,然后将其保存在 SD 卡中并在应用程序的 MainActivity 的 ImageView(image_view)(在 onRequestPermissionsResult() 方法中处理)上显示它。该应用程序还有助于将用户点击的图片通过电子邮件发送。现在为此,我请求了 2 个权限:
1.) 相机请求
2.) 外部存储请求
当应用启动时,相机请求对话框出现,但外部存储请求对话框未出现,应用崩溃并显示 toast,因为未授予外部写入权限。无法保存文件。
我在 list 中也提到了请求
<uses-permission android:name="android.permissions.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.CAMERA" />
请求权限代码
public void requestPermissions() {
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
} else {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,android.Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
Toast.makeText(this,
"External storage permission required to save images",
Toast.LENGTH_SHORT).show();
}
ActivityCompat.requestPermissions(this,new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE},
REQUEST_WRITE_EXTERNAL_STORAGE);
}
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
launchCamera();
} else {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,android.Manifest.permission.CAMERA)) {
Toast.makeText(this,
"External storage permission required to save images",
Toast.LENGTH_SHORT).show();
}
ActivityCompat.requestPermissions(this,new String[]{android.Manifest.permission.CAMERA},
REQUEST_CAMERA);
}
}
这里是完整代码
public class MainActivity extends AppCompatActivity {
Button clickPhotoButton;
private static final String FILE_NAME="image01.jpg";
private static final int CAMERA_PIC_REQUEST = 100;
private static final int REQUEST_WRITE_EXTERNAL_STORAGE = 1;
private static final int REQUEST_CAMERA = 2;
File pictureDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "Prakhar");
Uri fileUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
clickPhotoButton = (Button) findViewById(R.id.click_photo_button);
makeFolder();
}
public void makeFolder(){
if(!pictureDir.exists()) {
pictureDir.mkdirs();
}
Log.e("Prakhar", pictureDir.getAbsolutePath());
}
public void requestPermissions() {
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
} else {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,android.Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
Toast.makeText(this,
"External storage permission required to save images",
Toast.LENGTH_SHORT).show();
}
ActivityCompat.requestPermissions(this,new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE},
REQUEST_WRITE_EXTERNAL_STORAGE);
}
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
launchCamera();
} else {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,android.Manifest.permission.CAMERA)) {
Toast.makeText(this,
"External storage permission required to save images",
Toast.LENGTH_SHORT).show();
}
ActivityCompat.requestPermissions(this,new String[]{android.Manifest.permission.CAMERA},
REQUEST_CAMERA);
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
if(requestCode == REQUEST_WRITE_EXTERNAL_STORAGE ) {
if(grantResults[0] == PackageManager.PERMISSION_GRANTED) {
launchCamera();
} else {
Toast.makeText(this,
"External write permission has not been granted, cannot saved images",
Toast.LENGTH_SHORT).show();
}
} else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
if(requestCode == REQUEST_CAMERA) {
if(grantResults[0] == PackageManager.PERMISSION_GRANTED) {
launchCamera();
} else {
Toast.makeText(this,
"External write permission has not been granted, cannot saved images",
Toast.LENGTH_SHORT).show();
}
} else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
public void onPhotoClicked(View view) {
requestPermissions();
}
public void launchCamera() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
File image = new File(pictureDir, FILE_NAME);
fileUri = Uri.fromFile(image);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
startActivityForResult(intent, CAMERA_PIC_REQUEST);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(requestCode == CAMERA_PIC_REQUEST && resultCode == RESULT_OK) {
ImageView imageView = (ImageView) findViewById(R.id.image_view);
File image = new File(pictureDir, FILE_NAME);
fileUri = Uri.fromFile(image);
imageView.setImageURI(fileUri);
}
}
}
最佳答案
找到了。真是浪费时间。在我写的 list 文件中
android.permissions.WRITE_EXTERNAL_STORAGE
本来应该是这样的
android.permission.WRITE_EXTERNAL_STORAGE
关于android - 未出现权限请求对话框,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/44476163/