关于片段生命周期
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【中文标题】关于片段生命周期【英文标题】：About fragment life cycle 【发布时间】：2021-01-11 22:49:08 【问题描述】：我的片段中有一些奇怪的东西，当活动重新启动或暂停时，片段没有响应我的 onClick 事件，这是我的代码，我应该怎么做才能不再遇到这个问题 提示这是一个注册片段，它将模型对象返回给活动 throw communicator，我希望任何人都可以帮助我
import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.provider.MediaStore;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.constraintlayout.widget.ConstraintLayout;
import androidx.core.app.ActivityCompat;
import androidx.fragment.app.Fragment;
import com.gahez.gahez.Constants;
import com.gahez.gahez.Definer;
import com.gahez.gahez.R;
import com.gahez.gahez.activities.UserSignUpActivity;
import com.gahez.gahez.data_wrappers.Courier;
import com.gahez.gahez.fragments.interfaces.SignUpCommunicator;
import com.gahez.gahez.utilities.Utilities;
import java.io.File;
import java.io.IOException;
public class SignUpFragment extends Fragment implements View.OnClickListener, CompoundButton.OnCheckedChangeListener
private ImageView profilePicImageView;
private ImageView showPasswordIMageView;
private EditText passwordEditText;
private EditText emailEditText;
private EditText userNameEditText;
private EditText phoneEditText;
private EditText confirmPasswordEditText;
private EditText nationalIdEditText;
private Button signUpButton;
private TextView addImageTextView;
private CheckBox maleCheckBox;
private CheckBox femaleCheckBox;
private ConstraintLayout backgroundConstraintLayout;
public Activity context;
private Intent outComingIntent;
private SignUpCommunicator communicator;
private File userPhotoFile;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState)
return inflater.inflate(R.layout.signup_fragment,container,false);
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState)
super.onActivityCreated(savedInstanceState);
setContext();
setCommunicator();
defineViews();
setListeners();
Definer.setupUI(backgroundConstraintLayout,context);
//my methods
//---------------------------------------------------------------------------------------------
public void setListeners()
signUpButton.setOnClickListener(this);
maleCheckBox.setOnCheckedChangeListener(this);
femaleCheckBox.setOnCheckedChangeListener(this);
profilePicImageView.setOnClickListener(this);
public void defineViews()
profilePicImageView = context.findViewById(R.id.profile_pic);
showPasswordIMageView = context.findViewById(R.id.password_show);
passwordEditText =context.findViewById(R.id.password);
signUpButton=context.findViewById(R.id.next);
emailEditText= context.findViewById(R.id.email);
userNameEditText= context.findViewById(R.id.username);
phoneEditText= context.findViewById(R.id.phone_number);
confirmPasswordEditText= context.findViewById(R.id.conferim_password);
backgroundConstraintLayout=context.findViewById(R.id.background_constraint_layout);
addImageTextView = context.findViewById(R.id.add_image_text);
maleCheckBox=context.findViewById(R.id.male_check_box);
femaleCheckBox=context.findViewById(R.id.female_check_box);
nationalIdEditText= context.findViewById(R.id.national_id_edit_text);
public void setContext()
context=getActivity();
public void setCommunicator()
this.communicator =(SignUpCommunicator) getActivity();
public Courier getCourier()
Courier courier = null;
String email = emailEditText.getText().toString();
String password = passwordEditText.getText().toString();
String confirmationPassword = confirmPasswordEditText.getText().toString();
String phoneNumber = phoneEditText.getText().toString();
String userName = userNameEditText.getText().toString();
String nationalId = nationalIdEditText.getText().toString();
String gender = getGender();
if(!email.equals("")&&!password.equals("")&&!confirmationPassword.equals("")&&
!phoneNumber.equals("")&&!userName.equals("")&&!gender.equals("")&&!nationalId.equals(""))
courier = new Courier("carrier",userName,email,password,phoneNumber,
gender,nationalId);
return courier; //it returns null if any field is empty
public String getGender()
String gender="male";
if(femaleCheckBox.isChecked())
gender="female";
return gender;
public String validatePasswords()
String password = passwordEditText.getText().toString();
String confirmationPassword = confirmPasswordEditText.getText().toString();
if(password.equals(confirmationPassword))
if(password.length()>=8)
return Constants.VALID_PASSWORD;
else
return Constants.SHORT_PASSWORD;
else
return Constants.NOT_MATCHING_PASSWORDS;
public boolean isValidDataEntry(Courier courier)
if(courier==null) //if courier is null then the fun getCourier find one or more field empty
Toast.makeText(context, getString(R.string.complete_your_data), Toast.LENGTH_SHORT).show();
return false;
else
if(!Definer.validateEmailAddress(emailEditText.getText().toString()))
Toast.makeText(context, getString(R.string.invaild_email_address), Toast.LENGTH_SHORT).show();
return false;
else
String passwordValidationResult = validatePasswords();
if(passwordValidationResult.equals(Constants.SHORT_PASSWORD))
Toast.makeText(context, getString(R.string.password_must_be_eight_chars_at_least)
, Toast.LENGTH_SHORT).show();
return false;
else if(passwordValidationResult.equals(Constants.NOT_MATCHING_PASSWORDS))
Toast.makeText(context,
getString(R.string.passwords_are_not_matching),
Toast.LENGTH_SHORT).show();
return false;
else return true;
public boolean checkStoragePermissions()
if (ActivityCompat.checkSelfPermission(context, Manifest.permission.READ_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED && ActivityCompat.
checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED)
requestPermissions(Constants.STORAGE_PERMISSIONS,Constants.EXTERNAL_STORAGE_PERMISSIONS_REQUEST_CODE);
Log.d(Constants.LOG_TAG,"hello");
return false;
else
return true;
private void getImageFromDevice()
if(checkStoragePermissions())
outComingIntent = new Intent(Intent.ACTION_GET_CONTENT);
outComingIntent.setType("image/*");
startActivityForResult(outComingIntent, Constants.PROFILE_IMAGE_REQUEST_CODE);
//override methods
//----------------------------------------------------------------------------------------------
@Override
public void onClick(View v)
switch (v.getId())
case R.id.next:
Courier courier = getCourier();
if(isValidDataEntry(courier))
communicator.onSignUpDataConfirmed(courier);
break;
case R.id.profile_pic:
getImageFromDevice();
break;
@Override
public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data)
super.onActivityResult(requestCode, resultCode, data);
if(requestCode==context.RESULT_OK)
if(data!=null)
if(requestCode==Constants.PROFILE_IMAGE_REQUEST_CODE)
Uri imageUri = data.getData();
try
Bitmap profileImage = MediaStore.Images.Media.getBitmap(context.getContentResolver(),imageUri);
this.userPhotoFile = new File(Utilities.getRealPathFromURI(imageUri,context));
profilePicImageView.setImageBitmap(Utilities.resizeBigImages(profileImage));
catch (IOException e)
e.printStackTrace();
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults)
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode)
case Constants.EXTERNAL_STORAGE_PERMISSIONS_REQUEST_CODE:
if (ActivityCompat.checkSelfPermission(context, Manifest.permission.READ_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED)
if (Build.VERSION.SDK_INT >= 23 && !shouldShowRequestPermissionRationale(Constants.STORAGE_PERMISSIONS[0]))
Log.d(Constants.LOG_TAG, "noo");
Utilities.showBasicAlertDialog(
context,
R.drawable.ic_baseline_warning_24,
getString(R.string.permission_alert),
getString(R.string.go_to_settings_grant_the_storage_permissions_to_use_this_feature),
getString(R.string.ok),
null,
(dialog, which) ->
dialog.dismiss();
,
null
);
else
Utilities.showBasicAlertDialog(
context,
R.drawable.ic_baseline_warning_24,
getString(R.string.permission_alert),
getString(R.string.you_need_to_grant_storage_permissions),
getString(R.string.yes),
getString(R.string.not_now),
(dialog, which) ->
getImageFromDevice();
,
(dialog, which) ->
dialog.dismiss();
);
break;
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
switch (buttonView.getId())
case R.id.male_check_box:
if(isChecked)
femaleCheckBox.setChecked(false);
break;
case R.id.female_check_box:
if(isChecked)
maleCheckBox.setChecked(false);
break;
default:
break;
```
【问题讨论】：
【参考方案1】：我会尝试更改您拨打defineViews(); 和setListeners(); 的位置
onCreateView() 是执行此操作的理想位置，因为它是 Fragment 本身使用的方法，而不是 Activity 生命周期使用的方法。
而onActivityCreated() 仅在创建或重新附加片段时调用，但在重新启动时不调用。
【讨论】：
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