Android:：同一活动中的多个按钮

Question

这是我的问题：

我想在一个活动中实现两个按钮。一个是计算BMI，另一个是检查时间。我希望用户能在同一个活动中看到两个按钮，这也取决于他们想做什么。（这些功能不是同时工作的，而是分开的。另外，我在这两个活动中都实现了返回主页的按钮。）

在Android模拟器中，消息来自“应用程序继续停止”。

以下是主要活动。java文件：

 
 import android.content.Intent;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
 
 import androidx.appcompat.app.AppCompatActivity;
 
 public class MainActivity extends AppCompatActivity {
 
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
 
         // bt1 = to BMI  btn = TO DateCheck
         Button bt1 = findViewById(R.id.button1);
         Button btn = findViewById(R.id.button);
 
 
 
         bt1.setOnClickListener(v -> {
             // 指定要呼叫的 Activity Class
             Intent newAct = new Intent();
             newAct.setClass(MainActivity.this, BMI.class);
             // 呼叫新的 Activity Class
             startActivity(newAct);
 
 
         });
 
         btn.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 Intent newAct2 = new Intent();
                 newAct2.setClass(MainActivity.this,Time_Date.class);
                 startActivity(newAct2);
 
 
             }
         });
 
 
 
 
 
 
 
     }
 
 
 }

Following is the **Manifest.xml file**:

   
        
    
    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.example.myapplication">
    
        <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/Theme.MyApplication">
    
    
    
            <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=".Time_Date"/>
            <activity android:name=".BMI" />
    
        </application>
    
    </manifest>

Following is **activity_main.xml**:

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".MainActivity"
        android:background="#87CEEA">
    
    
        <!-- to BMI -->
        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentStart="true"
    
    
            android:layout_alignParentTop="true"
            android:layout_alignParentEnd="true"
            android:layout_marginStart="100dp"
    
            android:layout_marginLeft="100dp"
            android:layout_marginTop="50dp"
            android:layout_marginEnd="100dp"
            android:layout_marginRight="100dp"
    
            android:backgroundTint="@color/pink"
            android:text="@string/to_bmi"
            android:textAlignment="center"
            android:textColor="@color/purple_500"
            android:textStyle="bold"
            android:textSize="16sp"/>
    
        <!--to DateCheck-->
    
    
        <Button
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/button1"
            android:layout_alignParentStart="true"
            android:layout_alignParentEnd="true"
    
            android:layout_marginStart="100dp"
            android:layout_marginTop="30dp"
            android:layout_marginEnd="100dp"
    
            android:text="@string/view_datetime"
            android:textStyle="bold"
            android:textSize="16sp"
            android:textColor="@color/purple_500"
            android:backgroundTint="@color/pink"
    
    
    
            />
    </RelativeLayout>

谢谢！

这些消息是我按下导致应用程序停止的按钮后的stacktrace：

com.google.android.apps.gsa.shared.speech.b.g: Error reading from input stream
        at com.google.android.apps.gsa.staticplugins.recognizer.j.a.a(SourceFile:28)
        at com.google.android.apps.gsa.staticplugins.recognizer.j.b.run(SourceFile:15)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:457)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:457)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at com.google.android.apps.gsa.shared.util.concurrent.a.ag.run(Unknown Source:4)
        at com.google.android.apps.gsa.shared.util.concurrent.a.bo.run(SourceFile:4)
        at com.google.android.apps.gsa.shared.util.concurrent.a.bo.run(SourceFile:4)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
        at java.lang.Thread.run(Thread.java:764)
        at com.google.android.apps.gsa.shared.util.concurrent.a.ak.run(SourceFile:6)
     Caused by: com.google.android.apps.gsa.shared.exception.GsaIOException: Error code: 393238 | Buffer overflow, no available space.
        at com.google.android.apps.gsa.speech.audio.Tee.f(SourceFile:103)
        at com.google.android.apps.gsa.speech.audio.au.read(SourceFile:2)
        at java.io.InputStream.read(InputStream.java:101)
        at com.google.android.apps.gsa.speech.audio.ao.run(SourceFile:18)
        at com.google.android.apps.gsa.speech.audio.an.run(SourceFile:2)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:457) 
        at java.util.concurrent.FutureTask.run(FutureTask.java:266) 
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:457) 
        at java.util.concurrent.FutureTask.run(FutureTask.java:266) 
        at com.google.android.apps.gsa.shared.util.concurrent.a.ag.run(Unknown Source:4) 
        at com.google.android.apps.gsa.shared.util.concurrent.a.bo.run(SourceFile:4) 
        at com.google.android.apps.gsa.shared.util.concurrent.a.bo.run(SourceFile:4) 
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) 
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) 
        at java.lang.Thread.run(Thread.java:764) 
        at com.google.android.apps.gsa.shared.util.concurrent.a.ak.run(SourceFile:6)