-5

EMulator works fine, but when i hit run , the emulator will flash my interface design(layout) for a while then quit, and then come out with the message the apps has stopped working

MainActivity.Java

package com.example.xh3al3r.myapplication2;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.RelativeLayout;
import android.content.Intent;

public class MainActivity extends AppCompatActivity {
RelativeLayout rellay_mainentry,rellay_garden,rellay_app,rellay_salarm;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    rellay_mainentry=findViewById(R.id.rellay_mainentry);
    rellay_app=findViewById(R.id.rellay_app);
    rellay_garden=findViewById(R.id.rellay_garden);

    rellay_mainentry.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent=new Intent(MainActivity.this,MainEntry.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
            startActivity(intent);
        }
    });

    rellay_app.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent=new Intent(MainActivity.this,MainHApp.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
            startActivity(intent);
        }
    });


    rellay_garden.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent=new Intent(MainActivity.this,MainGarden.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
            startActivity(intent);
        }
    });

    rellay_salarm.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent=new Intent(MainActivity.this,MainAlarm.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
            startActivity(intent);
        }
    });

}

}

activity_main.xml

    <?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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=".MainActivity">

<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:ignore="MissingConstraints"
    tools:layout_editor_absoluteX="0dp"
    tools:layout_editor_absoluteY="0dp">
<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="240dp"
        android:background="@drawable/b1"
        android:gravity="bottom"
        android:text="Smart Resort System"
        android:textAlignment="center"
        android:textColor="@color/darkblue"
        android:textSize="24sp"/>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:weightSum="3">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_margin="10dp"
            android:layout_marginBottom="10dp"
            android:layout_marginLeft="20dp"
            android:layout_marginRight="20dp">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical">

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:orientation="vertical">


                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:layout_weight="1">

                        <RelativeLayout
                            android:id="@+id/rellay_mainentry"
                            android:layout_width="270dp"
                            android:layout_height="150dp"
                            android:layout_weight="0.75"
                            android:background="@color/red"
                            android:clickable="true">

                            <RelativeLayout
                                android:layout_width="161dp"
                                android:layout_height="wrap_content"
                                android:layout_centerHorizontal="true"
                                android:layout_marginTop="24dp">

                                <ImageView
                                    android:id="@+id/imgView1"
                                    android:layout_width="90dp"
                                    android:layout_height="88dp"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="0dp"
                                    android:adjustViewBounds="true"
                                    android:padding="8dp"
                                    android:scaleType="centerInside"
                                    android:src="@drawable/door" />

                                <TextView
                                    android:layout_width="wrap_content"
                                    android:layout_height="wrap_content"
                                    android:layout_below="@+id/imgView1"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="5dp"
                                    android:text="Entry Points"
                                    android:textAppearance="@android:style/TextAppearance" />

                            </RelativeLayout>

                        </RelativeLayout>

                        <RelativeLayout
                            android:id="@+id/rellay_app"
                            android:layout_width="match_parent"
                            android:layout_height="match_parent"
                            android:layout_weight="0.75"
                            android:background="@color/yellow"
                            android:clickable="true">

                            <RelativeLayout
                                android:layout_width="match_parent"
                                android:layout_height="156dp"
                                android:layout_centerInParent="true">

                                <ImageView
                                    android:id="@+id/apps"
                                    android:layout_width="86dp"
                                    android:layout_height="94dp"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="18dp"
                                    android:adjustViewBounds="true"
                                    android:padding="8dp"
                                    android:scaleType="centerInside"
                                    android:src="@drawable/homeapp"/>

                                <TextView
                                    android:layout_width="wrap_content"
                                    android:layout_height="wrap_content"
                                    android:layout_below="@+id/apps"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="5dp"
                                    android:text="Home Appliances"
                                    android:textAppearance="@android:style/TextAppearance.Holo.Widget.TextView"/>

                            </RelativeLayout>

                        </RelativeLayout>
                    </LinearLayout>
                    <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:layout_weight="1">

                        <RelativeLayout
                            android:id="@+id/rellay_garden"
                            android:layout_width="match_parent"
                            android:layout_height="150dp"
                            android:layout_weight="0.75"
                            android:background="@color/lime_dark"
                            android:clickable="true">

                            <RelativeLayout
                                android:layout_width="161dp"
                                android:layout_height="wrap_content"
                                android:layout_centerHorizontal="true"
                                android:layout_marginTop="24dp">

                                <ImageView
                                    android:id="@+id/watering"
                                    android:layout_width="127dp"
                                    android:layout_height="88dp"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="0dp"
                                    android:adjustViewBounds="true"
                                    android:padding="8dp"
                                    android:scaleType="centerInside"
                                    android:src="@drawable/water" />

                                <TextView
                                    android:layout_width="wrap_content"
                                    android:layout_height="wrap_content"
                                    android:layout_below="@+id/watering"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="5dp"
                                    android:text="Gardening"
                                    android:textAppearance="@android:style/TextAppearance" />

                            </RelativeLayout>

                        </RelativeLayout>

                        <RelativeLayout
                            android:id="@+id/rellay_salarm"
                            android:layout_width="match_parent"
                            android:layout_height="match_parent"
                            android:layout_weight="0.75"
                            android:background="@color/blue_dark"
                            android:clickable="true">

                            <RelativeLayout
                                android:layout_width="match_parent"
                                android:layout_height="156dp"
                                android:layout_centerInParent="true">

                                <ImageView
                                    android:id="@+id/alarms"
                                    android:layout_width="86dp"
                                    android:layout_height="94dp"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="18dp"
                                    android:adjustViewBounds="true"
                                    android:padding="8dp"
                                    android:scaleType="centerInside"
                                    android:src="@drawable/homeapp"/>

                                <TextView
                                    android:layout_width="wrap_content"
                                    android:layout_height="wrap_content"
                                    android:layout_below="@+id/alarms"
                                    android:layout_centerHorizontal="true"
                                    android:layout_marginTop="5dp"
                                    android:text="Alarms"
                                    android:textAppearance="@android:style/TextAppearance.Holo.Widget.TextView"/>

                            </RelativeLayout>

                        </RelativeLayout>
                    </LinearLayout>

                </LinearLayout>

            </LinearLayout>

        </RelativeLayout>

    </LinearLayout>

</LinearLayout>
</ScrollView>

</android.support.constraint.ConstraintLayout>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.xh3al3r.myapplication2">

    <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=".MainEntry" />
        <activity android:name=".MainGarden" />
        <activity android:name=".MainHApp" />
        <activity android:name=".MainAlarm"></activity>
    </application>

</manifest>

Logcat. Below is the error. The emulator appears but didnt show my design in layout

09-11 15:34:40.389 4910-4910/? E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.xh3al3r.myapplication2, PID: 4910
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.xh3al3r.myapplication2/com.example.xh3al3r.myapplication2.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.view.View.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
        at android.app.ActivityThread.-wrap12(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:154)
        at android.app.ActivityThread.main(ActivityThread.java:6119)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.view.View.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
        at com.example.xh3al3r.myapplication2.MainActivity.onCreate(MainActivity.java:48)
        at android.app.Activity.performCreate(Activity.java:6679)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
        at android.app.ActivityThread.-wrap12(ActivityThread.java) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
        at android.os.Handler.dispatchMessage(Handler.java:102) 
        at android.os.Looper.loop(Looper.java:154) 
        at android.app.ActivityThread.main(ActivityThread.java:6119) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 

I ady uninstall and reinstall agn yet the error is still the same

Phantômaxx
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1 Answers1

2

You're calling rellay_salarm.setOnClickListener() without actually initializing that variable.

rellay_salarm = findViewById(R.id.rellay_salarm);
TheWanderer
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