因此,我已经构建了这个简单的应用程序,作为我正在学习的自我指导学习android类的一部分。直到我对Java文件进行了一些更改,然后尝试重新安装并重新启动后,它的工作情况都很好。根据我所做的研究,我认为它与清单有关,但是我不确定这是什么错误。如果您需要查看其他内容,请询问。我真的很为难。在添加switch语句之前,它一直在工作。它曾经是一个if else
集群,并被告知要尝试使用switch statement
进行。它似乎在Eclipse中签出,但我无法弄清楚。这是logcat的输出。
01-22 07:43:12.106:E / libprocessgroup(1717):制作失败
/ acct / uid_10054:只读文件系统01-22 07:43:12.106:
W / Zygote(1717):createProcessGroup失败,缺少内核
CONFIG_CGROUP_CPUACCT? 01-22 07:43:12.107:I / art(1717):不
后期启用-Xcheck:jni(已启用)01-22 07:43:12.192:
D / AndroidRuntime(1717):关闭VM 01-22 07:43:12.192:
D / AndroidRuntime(1717):---------崩溃开始01-22
07:43:12.193:E / AndroidRuntime(1717):致命意外:主要01-22
07:43:12.193:E / AndroidRuntime(1717):进程:
com.codeherenow.trafficlights,PID:1717 01-22 07:43:12.193:
E / AndroidRuntime(1717):java.lang.RuntimeException:无法执行
实例化活动
ComponentInfo {com.codeherenow.trafficlights / com.codeherenow.trafficlights.TrafficLightsActivity}:
java.lang.InstantiationException:类
com.codeherenow.trafficlights.TrafficLightsActivity不能为
实例化01-22 07:43:12.193:E / AndroidRuntime(1717):at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2209)
01-22 07:43:12.193:E / AndroidRuntime(1717):at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
01-22 07:43:12.193:E / AndroidRuntime(1717):at
android.app.ActivityThread.access $ 800(ActivityThread.java:144)01-22
07:43:12.193:E / AndroidRuntime(1717):at
android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1278)
01-22 07:43:12.193:E / AndroidRuntime(1717):at
android.os.Handler.dispatchMessage(Handler.java:102)01-22
07:43:12.193:E / AndroidRuntime(1717):at
android.os.Looper.loop(Looper.java:135)01-22 07:43:12.193:
E / AndroidRuntime(1717):在
android.app.ActivityThread.main(ActivityThread.java:5221)01-22
07:43:12.193:E / AndroidRuntime(1717):at
java.lang.reflect.Method.invoke(本机方法)01-22 07:43:12.193:
E / AndroidRuntime(1717):在
java.lang.reflect.Method.invoke(Method.java:372)01-22 07:43:12.193:
E / AndroidRuntime(1717):在
com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:899)
01-22 07:43:12.193:E / AndroidRuntime(1717):at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)01-22
07:43:12.193:E / AndroidRuntime(1717):原因:
java.lang.InstantiationException:类
com.codeherenow.trafficlights.TrafficLightsActivity不能为
实例化01-22 07:43:12.193:E / AndroidRuntime(1717):at
java.lang.Class.newInstance(Class.java:1553)01-22 07:43:12.193:
E / AndroidRuntime(1717):在
android.app.Instrumentation.newActivity(Instrumentation.java:1065)
01-22 07:43:12.193:E / AndroidRuntime(1717):at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2199)
01-22 07:43:12.193:E / AndroidRuntime(1717):...还有10多个01-22
07:48:13.660:I / Process(1717):发送信号PID:1717 SIG:9
这是清单:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.codeherenow.trafficlights"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name">
<activity
android:name="com.codeherenow.trafficlights.TrafficLightsActivity"
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>
这是java:
package com.codeherenow.trafficlights;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
public abstract class TrafficLightsActivity extends Activity implements OnClickListener {
private ImageView redLight;
private ImageView yellowLight;
private ImageView greenLight;
private Button redButton;
private Button yellowButton;
private Button greenButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.traffic_lights);
redLight=(ImageView) findViewById(R.id.red_light);
yellowLight=(ImageView) findViewById(R.id.yellow_light);
greenLight=(ImageView) findViewById(R.id.green_light);
redButton=(Button) findViewById(R.id.Red_Button);
yellowButton=(Button) findViewById(R.id.Yellow_Button);
greenButton=(Button) findViewById(R.id.Green_Button);
redButton.setOnClickListener(this);
yellowButton.setOnClickListener(this);
greenButton.setOnClickListener(this);
redLight.setOnClickListener(this);
yellowLight.setOnClickListener(this);
greenLight.setOnClickListener(this);
}
public void onClick (View v) {
int v2=v.getId();
turnOffLight();
// TODO Auto-generated method stub
switch(v2){
case R.id.Red_Button:case R.id.red_light:
turnOnRedLight();
break;
case R.id.Yellow_Button: case R.id.yellow_light:
turnOnYellowLight();
break;
case R.id.Green_Button: case R.id.green_light:
turnOnGreenLight();
break;
default:
break;
}
}
private void turnOffLight() {
// TODO Auto-generated method stub
redLight.setImageResource(R.drawable.light_off);
greenLight.setImageResource(R.drawable.light_off);
yellowLight.setImageResource(R.drawable.light_off);
}
private void turnOnGreenLight() {
// TODO Auto-generated method stub
greenLight.setImageResource(R.drawable.green_on);
}
private void turnOnYellowLight() {
// TODO Auto-generated method stub
yellowLight.setImageResource(R.drawable.yellow_on);
}
private void turnOnRedLight() {
// TODO Auto-generated method stub
redLight.setImageResource(R.drawable.red_on);
}
}
最佳答案
public abstract class TrafficLightsActivity
并且您的错误是
Caused by: java.lang.InstantiationException:
..解决方案是
public class TrafficLightsActivity