按下按钮时，Android应用程序崩溃

时间：2014-02-26 19:52:15

标签： java android xml android-location

我制作了一个应用程序，该应用程序的一部分是获取经度和纬度将这些添加到一个字符串中并使用该字符串从天气服务器获取xml文件，以便您可以看到天气，温度，湿度..它就在你的位置。

activity_main.xml中：

<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=".MainActivity" >

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:text="@string/instruction_nexttobutton_english" />

<Button
    android:id="@+id/button2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_alignRight="@+id/textView1"
    android:layout_below="@+id/textView1"
    android:onClick="getPositionAndGetWheater"
    android:text="@string/getweather_button_english" />

<WebView
    android:id="@+id/webview"
    android:layout_width="wrap_content"
    android:layout_height="115dp"
    android:layout_alignLeft="@+id/button2"
    android:layout_alignRight="@+id/button2"
    android:layout_below="@+id/button2" />

</RelativeLayout>

MainActivity.java：

package com.example.thelexapp;

import android.location.Location;
import android.location.LocationManager;
import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.view.Menu;
import android.webkit.WebView;

public class MainActivity extends Activity {


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

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

public void getPositionAndGetWheater(View view) {
    LocationManager lm =                 (LocationManager)getSystemService(Context.LOCATION_SERVICE); 
    Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
    double longitude = location.getLongitude();
    double latitude = location.getLatitude();
    String longitudestring = String.valueOf(longitude);
    String latitudestring = String.valueOf(latitude);
    String URLforweather =     "http://api.worldweatheronline.com/free/v1/weather.ashx?q=" + longitudestring + "," + latitudestring + "&format=xml&num_of_days=1&key=IHAVEAAPIKEYBUTI'MNOTPOSTINGITONTHEFORUMFORSECURITYREASONS";
    WebView webview=(WebView)findViewById(R.id.webview); 
    webview.loadUrl(URLforweather);

}


}

“appname”Manifest.xml 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.thelexapp"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="18" />

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.thelexapp.MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

</manifest>

LOGCAT WINDOWS：

02-26 15:00:26.710: D/dalvikvm(977): Not late-enabling CheckJNI (already on)
02-26 15:00:29.730: V/WebViewChromium(977): Binding Chromium to the background looperLooper{b1dceb80}
02-26 15:00:29.750: I/chromium(977): [INFO:library_loader_hooks.cc(112)] Chromium     logging enabled: level = 0, default verbosity = 0
02-26 15:00:29.770: I/BrowserProcessMain(977): Initializing chromium process, renderers=0
02-26 15:00:29.960: E/chromium(977): [ERROR:gl_surface_egl.cc(153)] No suitable EGL configs found.
02-26 15:00:29.960: E/chromium(977): [ERROR:gl_surface_egl.cc(620)] GLSurfaceEGL::InitializeOneOff failed.
02-26 15:00:29.960: E/chromium(977): [ERROR:gl_surface_egl.cc(153)] No suitable EGL configs found.
02-26 15:00:29.960: E/chromium(977): [ERROR:gl_surface_egl.cc(620)] GLSurfaceEGL::InitializeOneOff failed.
02-26 15:00:29.970: E/chromium(977): [ERROR:gpu_info_collector.cc(86)] gfx::GLSurface::InitializeOneOff() failed
02-26 15:00:30.000: W/chromium(977): [WARNING:proxy_service.cc(888)] PAC support disabled because there is no system implementation
02-26 15:00:30.150: D/dalvikvm(977): GC_FOR_ALLOC freed 88K, 5% free 3235K/3392K, paused 48ms, total 50ms
02-26 15:00:30.160: I/dalvikvm-heap(977): Grow heap (frag case) to 4.297MB for 1127536-byte allocation
02-26 15:00:30.230: D/dalvikvm(977): GC_FOR_ALLOC freed 3K, 4% free 4333K/4496K, paused 67ms, total 67ms
02-26 15:00:30.800: D/gralloc_goldfish(977): Emulator without GPU emulation detected.
02-26 15:00:30.880: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:31.870: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:31.930: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:32.000: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:32.020: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:32.090: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:32.130: W/AwContents(977): nativeOnDraw failed; clearing to background color.
02-26 15:00:31.817: D/AndroidRuntime(977): Shutting down VM
02-26 15:00:31.817: W/dalvikvm(977): threadid=1: thread exiting with uncaught exception (group=0xb1af5b90)
02-26 15:00:31.827: E/AndroidRuntime(977): FATAL EXCEPTION: main
02-26 15:00:31.827: E/AndroidRuntime(977): Process: com.example.thelexapp, PID: 977
02-26 15:00:31.827: E/AndroidRuntime(977): java.lang.IllegalStateException: Could not execute method of the activity
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.view.View$1.onClick(View.java:3814)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.view.View.performClick(View.java:4424)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.view.View$PerformClick.run(View.java:18383)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.os.Handler.handleCallback(Handler.java:733)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.os.Handler.dispatchMessage(Handler.java:95)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.os.Looper.loop(Looper.java:137)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.app.ActivityThread.main(ActivityThread.java:4998)
02-26 15:00:31.827: E/AndroidRuntime(977):  at java.lang.reflect.Method.invokeNative(Native Method)
02-26 15:00:31.827: E/AndroidRuntime(977):  at java.lang.reflect.Method.invoke(Method.java:515)
02-26 15:00:31.827: E/AndroidRuntime(977):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
02-26 15:00:31.827: E/AndroidRuntime(977):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
02-26 15:00:31.827: E/AndroidRuntime(977):  at dalvik.system.NativeStart.main(Native Method)
02-26 15:00:31.827: E/AndroidRuntime(977): Caused by: java.lang.reflect.InvocationTargetException
02-26 15:00:31.827: E/AndroidRuntime(977):  at java.lang.reflect.Method.invokeNative(Native Method)
02-26 15:00:31.827: E/AndroidRuntime(977):  at java.lang.reflect.Method.invoke(Method.java:515)
02-26 15:00:31.827: E/AndroidRuntime(977):  at android.view.View$1.onClick(View.java:3809)
02-26 15:00:31.827: E/AndroidRuntime(977):  ... 11 more
02-26 15:00:31.827: E/AndroidRuntime(977): Caused by: java.lang.NullPointerException
02-26 15:00:31.827: E/AndroidRuntime(977):  at com.example.thelexapp.MainActivity.getPositionAndGetWheater(MainActivity.java:33)
02-26 15:00:31.827: E/AndroidRuntime(977):  ... 14 more
02-26 15:00:37.167: I/Process(977): Sending signal. PID: 977 SIG: 9

1 个答案:

答案 0 :(得分：0)

您是在模拟器或设备上进行测试吗？您的Location location是空的，这是可能的。请确保您的清单中有相应的权限。要处理此类情况，您应该检查null的位置：

public void getPositionAndGetWheater(View view) {
    LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
    if (location != null) {

        double longitude = location.getLongitude();
        double latitude = location.getLatitude();
        String longitudestring = String.valueOf(longitude);
        String latitudestring = String.valueOf(latitude);
        String URLforweather = "http://api.worldweatheronline.com/free/v1/weather.ashx?q=" + longitudestring + "," + latitudestring + "&format=xml&num_of_days=1&key=IHAVEAAPIKEYBUTI'MNOTPOSTINGITONTHEFORUMFORSECURITYREASONS";
        WebView webview = (WebView) findViewById(R.id.webview);
        webview.loadUrl(URLforweather);
    } else {
        //show error
    }

}
相关问题
最新问题