java - 如何让一个按钮在下一屏显示两个文本框的内容？

Question

我对编码还很陌生，这只是我在社区大学的第二个学期，因此我还有很多东西要学。

在我的 Android 开发类(class)中，我的任务是使用我在此处的 Android 开发类(class)中创建的程序 - https://developer.android.com/training/basics/firstapp/starting-activity#java - 作为新程序的基础，该程序有 2 个文本框，并通过单击 1 发送按钮将用户输入这些文本框的内容显示在显示屏上。

我卡住了。

自上周二发出挑战以来，我一直在做这个，我一直在谷歌搜索、DuckDuckGo 搜索、stackoverflow 搜索、此处搜索 - https://developer.android.com/docs/ - 我尝试了很多不同的方法，但我似乎无法找到如何实现这一点。

!!郑重声明:我并不是要别人为我编写程序/应用程序的代码。我只是想了解如何让这个 1 按钮将 2 个文本框内容发送到显示器 - 我想学习!!

//* activity_main.xml */

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:id="@+id/ColorActivity"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/Name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:ems="10"
        android:gravity="center"
        android:layout_toRightOf="@+id/Number"
        android:hint="edit_name_message"
        android:inputType="textPersonName"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:layout_below="@+id/Name"
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:layout_centerHorizontal="true"
        android:text="button_send"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/Number" />

    <EditText
        android:id="@+id/Number"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:ems="10"
        android:gravity="center"
        android:hint="edit_phone_message"
        android:inputType="phone"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/Name" />
</RelativeLayout>

//* DisplayMessge.java */

package com.example.testapp;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

import com.example.testapp.R;

public class DisplayMessage extends Activity {

    private TextView name;
    private TextView number;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.display_activity);

        name = findViewById(R.id.NameText);
        number = findViewById(R.id.NumberText);

        Intent getText = getIntent();
        String TheName = getText.getStringExtra("Name");
        String TheNumber = getText.getStringExtra("Number");

        name.setText(TheName);
        number.setText(TheNumber);
    }
}

//* MainActivity.java */

package com.example.testapp;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.example.testapp.DisplayMessage;
import com.example.testapp.R;

public class MainActivity extends AppCompatActivity {


    Button button;
    private EditText name;
    private EditText number;

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

        //initialization of the EditText and the Button
        name = (EditText) findViewById(R.id.Name);
        number = (EditText) findViewById(R.id.Number);
        button = findViewById(R.id.button);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {


                Intent intent = new Intent(getApplicationContext(), DisplayMessage.class);

                String mName = name.getText().toString();
                String mNumber = number.getText().toString();
                //Checking if the Entries are empty
                if (mName != null && mNumber != null) {
                    intent.putExtra("Name", mName);
                    intent.putExtra("Number", mNumber);
                    startActivity(intent);
                    finish();
                } else {
                    Toast.makeText(getApplicationContext(), "Text Entries Missing", Toast.LENGTH_SHORT).show();
                }
            }
        });
    }
}

//* AndroidManifest.xml */

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.testapp">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".DisplayMessage">
            <intent-filter>
                <action android:name="android.intent.action.VIEW"></action>
            </intent-filter>
        </activity>
    </application>

</manifest>

//* display_activity.xml */

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:orientation="horizontal"
    android:layout_height="match_parent">


    <TextView
        android:layout_gravity="center"
        android:id="@+id/NameText"
        android:layout_weight="1"
        android:textSize="18sp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
    <TextView
        android:id="@+id/NumberText"
        android:layout_gravity="center"
        android:textSize="18sp"
        android:layout_weight="1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

Answer 1

您必须实现 onClick 函数并从那里发送 Intent 。

public class MainActivity extends AppCompatActivity {


Button button;
private EditText name;  
private EditText number;

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

    //initialization of the EditText and the Button
     name = (EditText) findViewById(R.id.Name);
     number = (EditText) findViewById(R.id.Number);
     button = findViewById(R.id.button);

    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {


            Intent intent = new Intent(getApplicationContext(), DisplayMessage.class);

            String mName = name.getText().toString();
            String mNumber = number.getText().toString();
            //Checking if the Entries are empty
            if(mName!=null&&mNumber!=null) {
                intent.putExtra("Name", mName);
                intent.putExtra("Number", mNumber);
                startActivity(intent);
                finish();
            }else{
                Toast.makeText(getApplicationContext(),"Text Entries Missing",Toast.LENGTH_SHORT).show();
            }
        }
    });

和显示类:

public class DisplayMessage extends Activity {

 private TextView name;
 private TextView number;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.display_activity);

    name = findViewById(R.id.NameText);
    number = findViewById(R.id.NumberText);

    Intent getText = getIntent();
    String TheName =getText.getStringExtra("Name");
    String TheNumber =  getText.getStringExtra("Number");

    name.setText(TheName);
    number.setText(TheNumber);

}

另外不要忘记将您的 displayActivity 添加到 AndroidManifest.xml

 <activity android:name=".DisplayMessage">
        <intent-filter>
            <action android:name="android.intent.action.VIEW"></action>
        </intent-filter>
    </activity>

现在您必须为 DisplayMessageActivity 创建第二个用户界面，转到 res/layout，右键单击布局文件夹并创建一个名为 display_activity 的新布局。这是我的 display_activity.xml 代码:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android" 
android:layout_width="match_parent"
android:orientation="horizontal"
android:layout_height="match_parent">


<TextView
    android:layout_gravity="center"
    android:id="@+id/NameText"
    android:layout_weight="1"
    android:textSize="18sp"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />
<TextView
    android:id="@+id/NumberText"
    android:layout_gravity="center"
    android:textSize="18sp"
    android:layout_weight="1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />
</LinearLayout>

最后这是 activity_main 布局:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:id="@+id/ColorActivity"
android:layout_height="match_parent"
tools:context=".MainActivity">

<EditText
    android:id="@+id/Name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="32dp"
    android:ems="10"
    android:gravity="center"
    android:layout_toRightOf="@+id/Number"
    android:hint="edit_name_message"
    android:inputType="textPersonName"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

<Button
    android:layout_below="@+id/Name"
    android:id="@+id/button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="32dp"
    android:layout_centerHorizontal="true"
    android:text="button_send"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/Number" />

<EditText
    android:id="@+id/Number"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="32dp"
    android:ems="10"
    android:gravity="center"
    android:hint="edit_phone_message"
    android:inputType="phone"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/Name" />
 </RelativeLayout>