用户输入后如何显示名称

Question

如何在用户输入数据后显示名称以及如何使其成为一个按钮，我可以在那里添加一些东西使它类似于配置文件我希望你在其中添加一个警报但首先我必须制作这个数据库.

我真的不知道如何修复它我尝试了这段代码，但它不起作用，或者当我尝试添加时它总是导致强制关闭
name = edtName.getText().toString();

AccountInfo a = new AccountInfo(name);

import android.annotation.SuppressLint;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.TabLayout;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {
    private TabLayout tabLayout;
    private AppBarLayout appBarLayout;
    private ViewPager viewPager;
    private EditText edtName;
    private Button btnAdd;
    Spinner spin1;
    Spinner spin2;
    Spinner spin3;


    @SuppressLint("WrongConstant")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        tabLayout = findViewById(R.id.tablayout);
        appBarLayout = findViewById(R.id.bar);
        viewPager = findViewById(R.id.viewpager);

        edtName = findViewById(R.id.edtName);

        spin1 = findViewById(R.id.spinnerFrequency);
        spin2 = findViewById(R.id.SpinnerTime);
        spin3 = findViewById(R.id.SpinnerQty);
        btnAdd = findViewById(R.id.btnAdd);

        String  name = edtName.getText().toString();


        Adapter adapter = new Adapter(getSupportFragmentManager());
        /*screen*/
        adapter.AddFragment(new Drugfragment(), "Drug");
        adapter.AddFragment(new Appointmentfragment(), "Appointment");

        viewPager.setAdapter(adapter);
        tabLayout.setupWithViewPager(viewPager);
        tabLayout.setupWithViewPager(viewPager);

       /* DBHelper mDBHlpr = new DBHelper(this);
        AccountInfo a = new AccountInfo(name);
        mDBHlpr.insertRecord(a);


        String account_just_inserted = mDBHlpr.getAccountName();
        Log.d(
                "ACCOUNT INSERTED",
                "The Name of the account just inserted is :-" + account_just_inserted
        );*/



        final Account c = new Account();
        if(c==null) {

        }else{
           AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
            builder.setTitle("LOG IN");
            LayoutInflater inflater = MainActivity.this.getLayoutInflater();
            builder.setView(inflater.inflate(R.layout.account,null));
                    builder.setPositiveButton("Yes",new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog, int id) {

                                    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                                    LayoutInflater inflater = MainActivity.this.getLayoutInflater();


                                    builder.setView(inflater.inflate(R.layout.accountname,null));
                                    builder.setPositiveButton("Yes",new DialogInterface.OnClickListener(){
                                        public void onClick(DialogInterface dialog, int id) {

                                        }
                                    });


                                    builder.show();
                                }
                            });



            builder.setNegativeButton("No",new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            System.exit(0);
                        }
                    });

            builder.show();


        }

    }


    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        String text = parent.getItemAtPosition(position).toString();
        Toast.makeText(parent.getContext(), text, Toast.LENGTH_SHORT).show();

    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {

    }


    }

维护性

import android.annotation.SuppressLint;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.TabLayout;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {
    private TabLayout tabLayout;
    private AppBarLayout appBarLayout;
    private ViewPager viewPager;
    private EditText edtName;
    private Button btnAdd;
    Spinner spin1;
    Spinner spin2;
    Spinner spin3;

    @SuppressLint("WrongConstant")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        tabLayout = findViewById(R.id.tablayout);
        appBarLayout = findViewById(R.id.bar);
        viewPager = findViewById(R.id.viewpager);

        edtName = findViewById(R.id.edtName);

        spin1 = findViewById(R.id.spinnerFrequency);
        spin2 = findViewById(R.id.SpinnerTime);
        spin3 = findViewById(R.id.SpinnerQty);
        btnAdd = findViewById(R.id.btnAdd);



        Adapter adapter = new Adapter(getSupportFragmentManager());
        /*screen*/
        adapter.AddFragment(new Drugfragment(), "Drug");
        adapter.AddFragment(new Appointmentfragment(), "Appointment");

        viewPager.setAdapter(adapter);
        tabLayout.setupWithViewPager(viewPager);
        tabLayout.setupWithViewPager(viewPager);

       /* DBHelper mDBHlpr = new DBHelper(this);
        AccountInfo a = new AccountInfo(name);
        mDBHlpr.insertRecord(a);


        String account_just_inserted = mDBHlpr.getAccountName();
        Log.d(
                "ACCOUNT INSERTED",
                "The Name of the account just inserted is :-" + account_just_inserted
        );*/



        final Account c = new Account();
        if(c==null) {

        }else{
           AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
            builder.setTitle("LOG IN");
            LayoutInflater inflater = MainActivity.this.getLayoutInflater();
            builder.setView(inflater.inflate(R.layout.account,null));
                    builder.setPositiveButton("Yes",new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog, int id) {

                                    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                                    LayoutInflater inflater = MainActivity.this.getLayoutInflater();


                                    builder.setView(inflater.inflate(R.layout.accountname,null));
                                    builder.setPositiveButton("Yes",new DialogInterface.OnClickListener(){
                                        public void onClick(DialogInterface dialog, int id) {

                                        }
                                    });


                                    builder.show();
                                }
                            });



            builder.setNegativeButton("No",new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            System.exit(0);
                        }
                    });

            builder.show();


        }

    }


    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        String text = parent.getItemAtPosition(position).toString();
        Toast.makeText(parent.getContext(), text, Toast.LENGTH_SHORT).show();

    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {

    }


    }

Answer 1

您可以为此使用 textwatcher，每次 EditText 字段中的文本发生变化时，它都会更改您的名称字符串。

et1.addTextChangedListener(new TextWatcher() {
            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

                // TODO Auto-generated method stub
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

                // TODO Auto-generated method stub
            }

            @Override
            public void afterTextChanged(Editable s) {
              name = edtName.getText().toString();

    //it will change your name String every time when text is changing in EditText fiels
            }
        });

希望这是你想要的。

Answer 2

它相当简单。在 vb.net 上就是这样...... c# 只是略有不同。

    Dim b As New Button
    b.text = "New Button"
    b.Location = New Point(0, 0)
    AddHandler b.Click, AddressOf handle_click

    Private Sub handle_click(sender As Object, e As EventArgs)
     'code here to react to the buttons click.
    End Sub

这是一个包含大量信息的链接。希望对您有所帮助 Controls in Java