Question

我的代码在模拟器上编译并运行，但是当按下按钮时，它会停止并显示消息"the application stopped on unexpectedly"。我经常搜索并阅读一些相关的帖子，但他们没有帮助。你可以帮帮我吗？我收到以下消息："Fatal Exception:main"message main XML file

<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"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.testing.MainActivity" >

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/hello_world" />

<Button
    android:id="@+id/btnShowLocation"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:layout_marginBottom="93dp"
    android:paddingLeft="20dp"
    android:paddingRight="20dp" />
</RelativeLayout>

我的活动是

package com.example.testing;
import java.util.Arrays;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends Activity {
    double latituden;
    double longtituden;
    double [][] matrix_a = {{33.977517,51.456953},
                            {33.980738,51.426285},
                            {33.989817,51.433273},
                            {33.994729,51.437565},
                            {33.995928,51.447210},
                            {33.992708,51.446357},
                            {33.984604,51.436315},
                            {33.974430,51.433501},
                            {33.983399,51.445335},
                            {33.978474,51.466491}   
                  };{
    for (int i=0;i<matrix_a.length;i++)
    {
           latituden=i;
        for (int j=0;j<matrix_a.length;j++){
            longtituden=j;
        }}};

    Button btnShowLocation;

    // GPSTracker class
    GPSTracker gps;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main); 
        Toast.makeText(getApplicationContext(), "welcome to this app"  ,   Toast.LENGTH_LONG).show();    

        btnShowLocation = (Button) findViewById(R.id.btnShowLocation);

        // show location button click event
        btnShowLocation.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {        
                // create class object
                gps = new GPSTracker(MainActivity.this);

                // check if GPS enabled     
                 if(gps.canGetLocation()){

                    double latitude = gps.getLatitude();
                    double longitude = gps.getLongitude();

                    // \n is for new line
                    Toast.makeText(getApplicationContext(), "Your Location is - \nLat: " + latitude + "\nLong: " + longitude, Toast.LENGTH_LONG).show();    
            }else{
                // can't get location
                // GPS or Network is not enabled
                // Ask user to enable GPS/network in settings
                gps.showSettingsAlert();
            }

        for (int i=0;i<matrix_a.length;i++)
        {

            for (int j=0;j<matrix_a.length;j++){ 
                Distclass distclass= new Distclass(); 

                double[] distance = distclass.Calculate(gps.getLatitude(),gps.getLongitude(),latituden,longtituden);

                Arrays.sort(distance); 
               double  min = distance[0];
            System.out.println(min);

            Toast.makeText(getApplicationContext(),
                    "min distance from your location is - \nmin: " + min, Toast.LENGTH_LONG).show();
        }   
    };
}});}}

Answer 1

这可能会导致崩溃的原因有很多，而且您提供的详细信息我可以想到几个：

您是否已在Activity中声明了自己的活动。您的应用程序中的所有活动都必须在AndroidManifest.xml标记内（如此
）中声明
```
<application></application>
```
什么是GPSTracker？它是从某个地方进口的吗？崩溃可能与该类有关。
检查您的logcat。那里应该可以看到崩溃。可以从Android Studio访问Logcat功能。有关详情，请查看this

当emress / android中的peress botton意外停止我的应用程序

1 个答案: