Android Studio App在打开第二个活动时崩溃

时间:2017-07-31 23:52:05

标签: java android android-studio

我正在尝试编写一个应用程序,它在主要活动页面上连接到蓝牙,然后在第二个活动页面上,它将打开无声铃声模式。每次我点击按钮打开下一个活动时,应用程序都会关闭。根据Android Studio没有错误。

这是我的SecondActivity.java文件

package fonephree.fonephreeconnecttobluetooth;

import android.app.Activity;
import android.content.Context;
import android.media.AudioManager;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

    public class SecondActivity extends Activity {
        Button button;
        AudioManager audiomanager;
        Context context;
        TextView textview;

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

            button = (Button)findViewById(R.id.button6);

            textview = (TextView)findViewById(R.id.textView2);

            context = getApplicationContext();

            audiomanager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

            button.setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub

                    audiomanager.setRingerMode(AudioManager.RINGER_MODE_SILENT);

                    textview.setText("Silent Mode Enable");

                }
            });
        }

    }

这是我的activity_second.xml文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    android:background="@android:color/holo_orange_dark"
    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:layout_height="match_parent"
    tools:context="fonephree.fonephreeconnecttobluetooth.SecondActivity">

        <Button
            android:id="@+id/button6"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:text="Silent" />

        <TextView
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_above="@+id/button6"
            android:layout_centerHorizontal="true"
            android:layout_marginBottom="44dp"
            android:text="Silent Mode"
            android:textAppearance="?android:attr/textAppearanceLarge" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:srcCompat="@drawable/phree"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true" />

</RelativeLayout>

以防错误出现在我的AndroidManifest

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

    <uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.ACCESS_NOTIFICATION_POLICY" />

    <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=".SecondActivity"
            android:label="@string/title_activity_second"
            android:theme="@style/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="fonephree.fonephreeconnecttobluetooth.SecondActivity" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>

    </application>

</manifest>

编辑

我修复了代码,但现在应用程序仅在按下按钮时关闭,并且在打开应用程序之前未处于静音模式。按钮只是加强了静音模式,它实际上并没有打开它。

1 个答案:

答案 0 :(得分:0)

根据您提供的信息,您将XML设置为activity_main,而button6和textview2在activity_second.xml中定义

所以你的onCreate应该在下面解决问题

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

            button = (Button)findViewById(R.id.button6);

            textview = (TextView)findViewById(R.id.textView2);

            context = getApplicationContext();

            audiomanager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

            button.setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub

                    audiomanager.setRingerMode(AudioManager.RINGER_MODE_SILENT);

                    textview.setText("Silent Mode Enable");

                }
            });
        }