Android 将文件路径从片段传递到活动，反之亦然
我正在制作自己的应用程序来练习Android编程。我正在制作一个由3个片段+一个摘要片段组成的向导，特别是在第三个片段中，用户必须拍摄两张图片，然后将其传递给摘要（以及之前片段中收集的先前数据）。我没有得到的是，我必须返回到主要活动，并传递图像路径，以便在单击按钮返回摘要片段时调用它们 代码如下： MainActivity.javaAndroid 将文件路径从片段传递到活动，反之亦然,android,android-fragments,Android,Android Fragments,我正在制作自己的应用程序来练习Android编程。我正在制作一个由3个片段+一个摘要片段组成的向导，特别是在第三个片段中，用户必须拍摄两张图片，然后将其传递给摘要（以及之前片段中收集的先前数据）。我没有得到的是，我必须返回到主要活动，并传递图像路径，以便在单击按钮返回摘要片段时调用它们 代码如下： MainActivity.java public class MainActivity extends AppCompatActivity { private Button personal
public class MainActivity extends AppCompatActivity {
private Button personalData;
protected String strUsername;
private boolean isProfileReady;
protected SharedPreferences loginData;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView welcome = (TextView) findViewById(R.id.welcome);
personalData = (Button) findViewById(R.id.data);
personalData.setText("Profile Info");
personalData.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, WizardActivity.class);
intent.putExtra("profileReady", isProfileReady);
startActivityForResult(intent, 1);
}
});
loginData = getSharedPreferences("UserPrefs", MODE_PRIVATE);
String value = loginData.getString("Username", null);
if (value == null) {
welcome.setText("Welcome guest!");
personalData.setVisibility(View.INVISIBLE);
} else {
welcome.setText("Welcome " + loginData.getString("Username", strUsername) + "!");
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == RESULT_OK) {
isProfileReady = true;
personalData.setText("View Profile");
}
}
}
public class WizardActivity extends AppCompatActivity implements SummaryFragment.Images {
//region Variables
Button go;
WizardOne wizOne;
WizardTwo wizTwo;
WizardThree wizThree;
SummaryFragment summaryFragment;
Bitmap frontBitmap, backBitmap;
SharedPreferences wizardPrefs;
Bundle bundle = new Bundle();
int currentPage = 1;
public static final String FRONT_BITMAP_KEY = "frontBitmap", BACK_BITMAP_KEY = "backBitmap";
boolean isProfileReady;
//endregion
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
isProfileReady = getIntent().getBooleanExtra("profileReady", false);
Toast.makeText(this, "profileReady : " + isProfileReady, Toast.LENGTH_SHORT).show();
setContentView(R.layout.wizard_layout);
go = (Button) findViewById(R.id.go);
if (isProfileReady) {
/*bundle.getParcelable("frontBitmap");
bundle.getParcelable("backBitmap");*/
currentPage = 4;
go.setText("Home");
summaryFragment = new SummaryFragment();
summaryFragment.setArguments(bundle);
getSupportFragmentManager().beginTransaction().add(R.id.activity_layout, summaryFragment).commit();
} else {
wizOne = new WizardOne();
if (savedInstanceState == null)
getSupportFragmentManager().beginTransaction().add(R.id.activity_layout, wizOne).commit();
}
go.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (isProfileReady) {
Intent intent = new Intent();
setResult(RESULT_OK, intent);
finish();
} else {
nextFragment();
}
}
});
}
public void nextFragment() {
switch (currentPage) {
case 1:
if (wizOne.validate()) {
wizTwo = new WizardTwo();
changeFragment(wizTwo, R.id.activity_layout);
currentPage++;
} else {
Toast.makeText(getApplicationContext(), "Fill the fields", Toast.LENGTH_SHORT).show();
}
break;
case 2:
if (wizTwo.validate()) {
wizThree = new WizardThree();
changeFragment(wizThree, R.id.activity_layout);
currentPage++;
} else {
Toast.makeText(getApplicationContext(), "Fill the fields", Toast.LENGTH_SHORT).show();
}
break;
case 3:
if (wizThree.validate()) {
bundle.putParcelable("frontBitmap", wizThree.getFrontBitmap());
bundle.putParcelable("backBitmap", wizThree.getBackBitmap());
summaryFragment = new SummaryFragment();
summaryFragment.setArguments(bundle);
go.setText("Home");
changeFragment(summaryFragment, R.id.activity_layout);
currentPage++;
}
break;
case 4:
passImages();
setResult(RESULT_OK);
finish();
break;
default:
break;
}
}
public void changeFragment(ValidateFragment f, int resource) {
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(resource, f);
transaction.addToBackStack(null);
transaction.commit();
}
public Bitmap getFrontBitmap() {
return frontBitmap;
}
public Bitmap getBackBitmap() {
return backBitmap;
}
@Override
public void onBackPressed() {
if (currentPage > 1) {
currentPage--;
getSupportFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
@Override
public Bundle passImages() {
bundle.getParcelable("frontBitmap");
bundle.getParcelable("backBitmap");
return bundle;
}
}
public class MainActivity extends AppCompatActivity {
private Button personalData;
protected String strUsername;
private boolean isProfileReady;
protected SharedPreferences loginData;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView welcome = (TextView) findViewById(R.id.welcome);
personalData = (Button) findViewById(R.id.data);
personalData.setText("Profile Info");
personalData.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, WizardActivity.class);
intent.putExtra("profileReady", isProfileReady);
startActivityForResult(intent, 1);
}
});
loginData = getSharedPreferences("UserPrefs", MODE_PRIVATE);
String value = loginData.getString("Username", null);
if (value == null) {
welcome.setText("Welcome guest!");
personalData.setVisibility(View.INVISIBLE);
} else {
welcome.setText("Welcome " + loginData.getString("Username", strUsername) + "!");
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == RESULT_OK) {
isProfileReady = true;
personalData.setText("View Profile");
}
}
}
public class WizardActivity extends AppCompatActivity implements SummaryFragment.Images {
//region Variables
Button go;
WizardOne wizOne;
WizardTwo wizTwo;
WizardThree wizThree;
SummaryFragment summaryFragment;
Bitmap frontBitmap, backBitmap;
SharedPreferences wizardPrefs;
Bundle bundle = new Bundle();
int currentPage = 1;
public static final String FRONT_BITMAP_KEY = "frontBitmap", BACK_BITMAP_KEY = "backBitmap";
boolean isProfileReady;
//endregion
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
isProfileReady = getIntent().getBooleanExtra("profileReady", false);
Toast.makeText(this, "profileReady : " + isProfileReady, Toast.LENGTH_SHORT).show();
setContentView(R.layout.wizard_layout);
go = (Button) findViewById(R.id.go);
if (isProfileReady) {
/*bundle.getParcelable("frontBitmap");
bundle.getParcelable("backBitmap");*/
currentPage = 4;
go.setText("Home");
summaryFragment = new SummaryFragment();
summaryFragment.setArguments(bundle);
getSupportFragmentManager().beginTransaction().add(R.id.activity_layout, summaryFragment).commit();
} else {
wizOne = new WizardOne();
if (savedInstanceState == null)
getSupportFragmentManager().beginTransaction().add(R.id.activity_layout, wizOne).commit();
}
go.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (isProfileReady) {
Intent intent = new Intent();
setResult(RESULT_OK, intent);
finish();
} else {
nextFragment();
}
}
});
}
public void nextFragment() {
switch (currentPage) {
case 1:
if (wizOne.validate()) {
wizTwo = new WizardTwo();
changeFragment(wizTwo, R.id.activity_layout);
currentPage++;
} else {
Toast.makeText(getApplicationContext(), "Fill the fields", Toast.LENGTH_SHORT).show();
}
break;
case 2:
if (wizTwo.validate()) {
wizThree = new WizardThree();
changeFragment(wizThree, R.id.activity_layout);
currentPage++;
} else {
Toast.makeText(getApplicationContext(), "Fill the fields", Toast.LENGTH_SHORT).show();
}
break;
case 3:
if (wizThree.validate()) {
bundle.putParcelable("frontBitmap", wizThree.getFrontBitmap());
bundle.putParcelable("backBitmap", wizThree.getBackBitmap());
summaryFragment = new SummaryFragment();
summaryFragment.setArguments(bundle);
go.setText("Home");
changeFragment(summaryFragment, R.id.activity_layout);
currentPage++;
}
break;
case 4:
passImages();
setResult(RESULT_OK);
finish();
break;
default:
break;
}
}
public void changeFragment(ValidateFragment f, int resource) {
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(resource, f);
transaction.addToBackStack(null);
transaction.commit();
}
public Bitmap getFrontBitmap() {
return frontBitmap;
}
public Bitmap getBackBitmap() {
return backBitmap;
}
@Override
public void onBackPressed() {
if (currentPage > 1) {
currentPage--;
getSupportFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
@Override
public Bundle passImages() {
bundle.getParcelable("frontBitmap");
bundle.getParcelable("backBitmap");
return bundle;
}
}
public class WizardThree extends ValidateFragment {
Button photos, deleteFirst, deleteSecond, button;
TextView frontText, backText, textView;
ImageView frontPhoto, backPhoto, imageView;
static final int REQUEST_IMAGE_CAPTURE = 1;
String path;
File photo = null;
Uri photoURI_1, photoURI_2, uri, uriOut;
private Bitmap frontBitmap, backBitmap;
public WizardThree() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_wizard_three, container, false);
photos = (Button) v.findViewById(R.id.photos);
photos.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent capture = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (capture.resolveActivity(getActivity().getPackageManager()) != null) {
try {
photo = createImgFile();
} catch (IOException e) {
Log.d("No,", " non funziona");
}
if (photo != null) {
uriOut = FileProvider.getUriForFile(WizardThree.this.getContext(), "com.example.android.fileprovider", photo);
capture.putExtra(MediaStore.EXTRA_OUTPUT, uriOut);
startActivityForResult(capture, REQUEST_IMAGE_CAPTURE);
}
}
}
});
frontText = (TextView) v.findViewById(R.id.frontText);
frontPhoto = (ImageView) v.findViewById(R.id.frontPhoto);
deleteFirst = (Button) v.findViewById(R.id.deleteFirst);
deleteFirst.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
deletePhoto(frontPhoto, frontText, deleteFirst);
}
});
backText = (TextView) v.findViewById(R.id.backText);
backPhoto = (ImageView) v.findViewById(R.id.backPhoto);
deleteSecond = (Button) v.findViewById(R.id.deleteSecond);
deleteSecond.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
deletePhoto(backPhoto, backText, deleteSecond);
}
});
return v;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_IMAGE_CAPTURE) {
if (frontPhoto.getDrawable() == null) {
photoURI_1 = uriOut;
frontBitmap = putPhoto(frontPhoto, frontText, deleteFirst, photoURI_1);
checkButton();
} else if (backPhoto.getDrawable() == null) {
photoURI_2 = uriOut;
backBitmap = putPhoto(backPhoto, backText, deleteSecond, photoURI_2);
checkButton();
}
}
}
//region getBitmaps
public Bitmap getFrontBitmap() {
return frontBitmap;
}
public Bitmap getBackBitmap() {
return backBitmap;
}
//endregion
public Bitmap putPhoto(ImageView imageView, TextView textView, Button button, Uri uri) {
Bitmap bitmap = BitmapFactory.decodeFile(path);
bitmap = Bitmap.createScaledBitmap(bitmap, bitmap.getWidth() / 3, bitmap.getHeight() / 3, true);
imageView.setImageBitmap(bitmap);
textView.setVisibility(View.VISIBLE);
imageView.setVisibility(View.VISIBLE);
button.setVisibility(View.VISIBLE);
return bitmap;
}
public void checkButton() {
if ((frontPhoto.getDrawable() != null) && (backPhoto.getDrawable() != null)) {
photos.setEnabled(false);
} else {
photos.setEnabled(true);
}
}
private File createImgFile() throws IOException {
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imgName = "JPEG_" + timeStamp + "_";
File storage = getActivity().getExternalFilesDir(Environment.DIRECTORY_PICTURES);
File img = File.createTempFile(imgName, ".jpg", storage);
path = img.getAbsolutePath();
return img;
}
public void deletePhoto(ImageView imageView, TextView text, Button btn) {
imageView.setImageDrawable(null);
text.setVisibility(View.GONE);
btn.setVisibility(View.GONE);
checkButton();
}
@Override
public void onDetach() {
super.onDetach();
}
@Override
public boolean validate() {
if ((frontPhoto.getDrawable() == null) || (backPhoto.getDrawable() == null)) {
Toast.makeText(getContext(), "Both photos are necessary", Toast.LENGTH_SHORT).show();
return false;
}
public class SummaryFragment extends ValidateFragment {
//region Variables
TextView getFName, getLName, getFisCode, getBirth, getCity, getProv, getZip, getCC, getIban, getMail;
ImageView imgOne, imgTwo;
String strFName, strLName, strFisCode, strBirth, strCity, strZip, strProv, strCC, strIban, strMail, path;
SharedPreferences wizardPrefs;
private Bitmap frontBitmap = null;
private Bitmap backBitmap = null;
Uri uri;
Images callBack;
//endregion
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
frontBitmap = getArguments().getParcelable("frontBitmap");
backBitmap = getArguments().getParcelable("backBitmap");
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
View v = inflater.inflate(R.layout.summary_layout, container, false);
//region findViewById
getFName = (TextView) v.findViewById(R.id.getFName);
getLName = (TextView) v.findViewById(R.id.getLName);
getFisCode = (TextView) v.findViewById(R.id.getFisCode);
getBirth = (TextView) v.findViewById(R.id.getBirth);
getCity = (TextView) v.findViewById(R.id.getCity);
getProv = (TextView) v.findViewById(R.id.getProv);
getZip = (TextView) v.findViewById(R.id.getZip);
getCC = (TextView) v.findViewById(R.id.getCC);
getIban = (TextView) v.findViewById(R.id.getIban);
getMail = (TextView) v.findViewById(R.id.getMail);
imgOne = (ImageView) v.findViewById(R.id.imgOne);
imgTwo = (ImageView) v.findViewById(R.id.imgTwo);
//endregion
wizardPrefs = this.getActivity().getSharedPreferences("USERDATA", Context.MODE_PRIVATE);
getFName.setText(wizardPrefs.getString("Nome utente", strFName));
getLName.setText(wizardPrefs.getString("Cognome utente", strLName));
getFisCode.setText(wizardPrefs.getString("Codice Fiscale", strFisCode));
getBirth.setText(wizardPrefs.getString("Data di nascita", strBirth));
getCity.setText(wizardPrefs.getString("Città", strCity));
getZip.setText(wizardPrefs.getString("CAP", strZip));
getProv.setText(wizardPrefs.getString("Provincia", strProv));
getCC.setText(wizardPrefs.getString("CC", strCC));
getIban.setText(wizardPrefs.getString("IBAN", strIban));
getMail.setText(wizardPrefs.getString("E-mail", strMail));
imgOne.setImageBitmap(frontBitmap);
imgTwo.setImageBitmap(backBitmap);
return v;
}
@Override
public boolean validate() {
return false;
}
public Bitmap getFrontBitmap() {
return frontBitmap;
}
public Bitmap getBackBitmap() {
return backBitmap;
}
public interface Images {
Bundle passImages();
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
try {
callBack = (Images) context;
} catch (ClassCastException c) {
throw new ClassCastException(context.toString() + "Exception thrown");
}
}
}
return true;
}
}
有人能帮我弄清楚吗？您已经有了活动结果，所以：
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == RESULT_OK) {
isProfileReady = true;
String imageOne = data.getStringExtra("imageOne");
}
}
Intent intent = new Intent();
intent.putExtra("ImageOne", imageOne);
setResult(RESULT_OK, intent);
finish();
您可以使用片段中的共享首选项，然后在活动中读取。这样，片段和活动之间就没有紧密耦合 从这里读一个很好的例子。
但是，如果我错了，请纠正我，我不能在任何非活动的内容中使用
setResultdata.getStringExtra（）NullPointerException这个.getActivity（）.setResult（…）