安卓 |创建多屏应用

本文展示了如何创建一个 android 应用程序以从一个活动移动到另一个活动。

以下是创建一个简单的 Android 应用程序以从一个活动移动到另一个活动的步骤。

STEP-1：创建新项目，您的项目屏幕如下所示。

第 2 步：您将拥有 xml 和活动Java文件，下面给出了这两个文件的路径。

第 3 步：打开您的 xml 文件并添加按钮，因为单击此按钮后，我们将移至第二个活动，如下所示。为消息添加 TextView。将 ID 分配给 Button 和 TextView 。

STEP-4：现在我们必须创建另一个活动（SecondActivity）以从一个活动移动到另一个活动。创建第二个活动并转到 android 项目 > 文件 > 新建 > 活动 > 空活动

STEP-5:现在打开你的第二个xml文件，这个文件的路径和第一个xml文件一样。为消息添加 TextView 并添加 2 个按钮，一个用于下一个活动，第二个用于上一个活动。将 ID 分配给 Textview 和两个 Button。第二个活动如下图所示：

STEP-6：现在，我们必须创建与第二个活动相同的第三个活动，并且该文件的路径也与另一个相同。（“现在，您可以创建许多这样的活动”）这里我们为消息添加TextView，为消息添加一个按钮转到上一个活动。如下图所示

第 7 步：现在，打开您的第一个活动Java文件。定义 Button（next_button 或可以是 previous_button）和 TextView 变量，使用 findViewById() 获取 Button 和 TextView。

STEP-8：我们需要将点击监听器添加到所有按钮（next_button或者可以是previous_button）。

第 9 步：当在 onclicklistener 方法中单击按钮时，创建一个 Intent 以启动一个称为另一个活动的活动。

第10 步：对每个活动重复第 7、8、9 步。

第 11 步：现在运行应用程序并单击可以转到第二个活动的按钮。
在第一个活动中，这里只有一个 Button 和 TextView

OneActivity的完整代码。下面是 Firstactivity 的Java或 activity_oneactivity.xml。

文件名：activity_oneactivity.xml

文件名：OneActivity。Java

Java

// Each new activity has its own layout and Java files,
package org.geeksforgeeks.navedmalik.multiplescreenapp;
 
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
 
public class Oneactivity extends AppCompatActivity {
 
    // define the global variable
 
    TextView question1;
    // Add button Move to Activity
 
    Button next_Activity_button;
 
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_oneactivity);
 
        // by ID we can use each component which id is assign in xml file
        // use findViewById() to get the Button
        next_Activity_button = (Button)findViewById(R.id.first_activity_button);
        question1 = (TextView)findViewById(R.id.question1_id);
 
        // In question1 get the TextView use by findViewById()
        // In TextView set question Answer for message
        question1.setText("Q 1 - How to pass the data between activities in Android?\n"
                          + "\n"
                          + "Ans- Intent");
 
        // Add_button add clicklistener
        next_Activity_button.setOnClickListener(new View.OnClickListener() {
 
            public void onClick(View v)
            {
 
                // Intents are objects of the android.content.Intent type. Your code can send them
                // to the Android system defining the components you are targeting.
                // Intent to start an activity called SecondActivity with the following code:
 
                Intent intent = new Intent(Oneactivity.this, SecondActivity.class);
 
                // start the activity connect to the specified class
                startActivity(intent);
            }
        });
    }
}

注意：这里我们将为消息添加 Next Button 和 previous Button 和 textView。

SecondActivity的完整代码。下面是第二个活动的Java或 activity_second.xml。

文件名：activity_second.xml

文件名：第二活动。Java

Java

package org.geeksforgeeks.navedmalik.multiplescreenapp;
 
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.content.Intent;
import android.widget.TextView;
 
public class SecondActivity extends AppCompatActivity {
 
    // define the global variable
    TextView question2;
    // Add button Move to next Activity and previous Activity
    Button next_button, previous_button;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
 
        // by ID we can use each component which id is assign in xml file
        // use findViewById() to get the both Button and textview
 
        next_button = (Button)findViewById(R.id.second_activity_next_button);
        previous_button = (Button)findViewById(R.id.second_activity_previous_button);
        question2 = (TextView)findViewById(R.id.question2_id);
 
        // In question1 get the TextView use by findViewById()
        // In TextView set question Answer for message
 
        question2.setText("Q 2 - What is ADB in android?\n"
                          + "\n"
                          + "Ans- Android Debug Bridge");
 
        // Add_button add clicklistener
        next_button.setOnClickListener(new View.OnClickListener() {
 
            public void onClick(View v)
            {
 
                // Intents are objects of the android.content.Intent type. Your code can send them
                // to the Android system defining the components you are targeting.
                // Intent to start an activity called ThirdActivity with the following code:
 
                Intent intent = new Intent(SecondActivity.this, ThirdActivity.class);
 
                // start the activity connect to the specified class
                startActivity(intent);
            }
        });
 
        // Add_button add clicklistener
        previous_button.setOnClickListener(new View.OnClickListener() {
 
            public void onClick(View v)
            {
 
                // Intents are objects of the android.content.Intent type. Your code can send them
                // to the Android system defining the components you are targeting.
                // Intent to start an activity called oneActivity with the following code:
 
                Intent intent = new Intent(SecondActivity.this, Oneactivity.class);
 
                // start the activity connect to the specified class
                startActivity(intent);
            }
        });
    }
}

注意：这里我们只为消息添加 Next Button 和 textView。

ThirdActivity 的完整代码。下面是第三个活动的Java或 activity_third.xml。

文件名：activity_third.xml

文件名：ThirdActivity。Java

Java

package org.geeksforgeeks.navedmalik.multiplescreenapp;
 
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.content.Intent;
import android.widget.TextView;
 
public class ThirdActivity extends AppCompatActivity {
 
    // define the global variable
    TextView question3;
    // Add button Move previous activity
    Button previous_button;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_third);
 
        // by ID we can use each component which id is assign in xml file
        // use findViewById() to get the Button and textview.
 
        previous_button = (Button)findViewById(R.id.third_activity_previous_button);
        question3 = (TextView)findViewById(R.id.question3_id);
 
        // In question1 get the TextView use by findViewById()
        // In TextView set question Answer for message
 
        question3.setText("Q 3 - How to store heavy structured data in android?\n"
                          + "\n"
                          + "Ans- SQlite database");
        // Add_button add clicklistener
        previous_button.setOnClickListener(new View.OnClickListener() {
 
            public void onClick(View v)
            {
 
                // Intents are objects of the android.content.Intent type. Your code can send them
                // to the Android system defining the components you are targeting.
                // Intent to start an activity called SecondActivity with the following code:
 
                Intent intent = new Intent(ThirdActivity.this, SecondActivity.class);
 
                // start the activity connect to the specified class
                startActivity(intent);
            }
        });
    }
}

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