Android LogCat是压倒性的,我不知道;我不知道该怎么办。。。应用程序打开后关闭?
这是java文件,唯一使用的文件…如果我知道错误的意思,我可以自己做Android LogCat是压倒性的,我不知道;我不知道该怎么办。。。应用程序打开后关闭?,android,android-emulator,android-2.2-froyo,Android,Android Emulator,Android 2.2 Froyo,这是java文件,唯一使用的文件…如果我知道错误的意思,我可以自己做 package tip.calculator; import android.os.Bundle; import android.app.Activity; import android.view.View.OnClickListener; import android.widget.EditText; import android.widget.TextView; import android.view.View; im
package tip.calculator;
import android.os.Bundle;
import android.app.Activity;
import android.view.View.OnClickListener;
import android.widget.EditText;
import android.widget.TextView;
import android.view.View;
import android.widget.Button;
public class TipCalculator extends Activity
{
private Button enter;
EditText myEditField = (EditText) findViewById(R.id.percentText);
final EditText myEditField2 = (EditText) findViewById(R.id.billText);
float percentage = 0;
float percentageInp = 0;
float billAmount = 0;
double output = 0;
String output1 = "";
Button clearButton = (Button) findViewById(R.id.clearButton);
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myEditField = (EditText) findViewById(R.id.percentText);
enter = (Button)findViewById(R.id.button1);
enter.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
TextView textView;
TextView errors;
textView = (TextView) findViewById(R.id.textView1);
errors = (TextView) findViewById(R.id.errorText);
for(;;){
if(myEditField == null){
break;
}
if(myEditField2 == null){
break;
}
}
percentageInp = Float.parseFloat(myEditField.getText().toString());
billAmount = Float.parseFloat(myEditField2.getText().toString());
percentage = ((float)percentageInp /100);
output = (double)(billAmount * percentage);
double result = output * 100;
result = Math.round(result);
result = result / 100;
output1 = Double.toString(result);
textView.setText(output1 + " $");
}
});
clearButton.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
percentage = 0;
output = 0;
output1 = "";
TextView textView;
textView = (TextView) findViewById(R.id.textView1);
textView.setText("");
percentageInp = 0;
billAmount = 0;
myEditField.setText("");
myEditField2.setText("");
}
});
}
}
这是logcat,我不知道这些错误是什么意思,也不知道如何处理它们。。。注意:这些仅在应用程序打开时生成,然后崩溃
08-01 15:37:43.934: E/Trace(671): error opening trace file: No such file or directory (2)
08-01 15:37:44.704: E/AndroidRuntime(671): FATAL EXCEPTION: main
08-01 15:37:44.704: E/AndroidRuntime(671): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{tip.calculator/tip.calculator.TipCalculator}: java.lang.NullPointerException
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.ActivityThread.access$600(ActivityThread.java:130)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.os.Handler.dispatchMessage(Handler.java:99)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.os.Looper.loop(Looper.java:137)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.ActivityThread.main(ActivityThread.java:4745)
08-01 15:37:44.704: E/AndroidRuntime(671): at java.lang.reflect.Method.invokeNative(Native Method)
08-01 15:37:44.704: E/AndroidRuntime(671): at java.lang.reflect.Method.invoke(Method.java:511)
08-01 15:37:44.704: E/AndroidRuntime(671): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
08-01 15:37:44.704: E/AndroidRuntime(671): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
08-01 15:37:44.704: E/AndroidRuntime(671): at dalvik.system.NativeStart.main(Native Method)
08-01 15:37:44.704: E/AndroidRuntime(671): Caused by: java.lang.NullPointerException
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.Activity.findViewById(Activity.java:1825)
08-01 15:37:44.704: E/AndroidRuntime(671): at tip.calculator.TipCalculator.<init>(TipCalculator.java:19)
08-01 15:37:44.704: E/AndroidRuntime(671): at java.lang.Class.newInstanceImpl(Native Method)
08-01 15:37:44.704: E/AndroidRuntime(671): at java.lang.Class.newInstance(Class.java:1319)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
08-01 15:37:44.704: E/AndroidRuntime(671): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
08-01 15:37:44.704: E/AndroidRuntime(671): ... 11 more
08-01 15:38:44.993: E/Trace(741): error opening trace file: No such file or directory (2)
08-01 15:38:45.123: E/AndroidRuntime(741): FATAL EXCEPTION: main
08-01 15:38:45.123: E/AndroidRuntime(741): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{tip.calculator/tip.calculator.TipCalculator}: java.lang.NullPointerException
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.ActivityThread.access$600(ActivityThread.java:130)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.os.Handler.dispatchMessage(Handler.java:99)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.os.Looper.loop(Looper.java:137)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.ActivityThread.main(ActivityThread.java:4745)
08-01 15:38:45.123: E/AndroidRuntime(741): at java.lang.reflect.Method.invokeNative(Native Method)
08-01 15:38:45.123: E/AndroidRuntime(741): at java.lang.reflect.Method.invoke(Method.java:511)
08-01 15:38:45.123: E/AndroidRuntime(741): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
08-01 15:38:45.123: E/AndroidRuntime(741): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
08-01 15:38:45.123: E/AndroidRuntime(741): at dalvik.system.NativeStart.main(Native Method)
08-01 15:38:45.123: E/AndroidRuntime(741): Caused by: java.lang.NullPointerException
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.Activity.findViewById(Activity.java:1825)
08-01 15:38:45.123: E/AndroidRuntime(741): at tip.calculator.TipCalculator.<init>(TipCalculator.java:19)
08-01 15:38:45.123: E/AndroidRuntime(741): at java.lang.Class.newInstanceImpl(Native Method)
08-01 15:38:45.123: E/AndroidRuntime(741): at java.lang.Class.newInstance(Class.java:1319)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
08-01 15:38:45.123: E/AndroidRuntime(741): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
08-01 15:38:45.123: E/AndroidRuntime(741): ... 11 more
08-01 15:37:43.934:E/Trace(671):打开跟踪文件时出错:没有这样的文件或目录(2)
08-01 15:37:44.704:E/AndroidRuntime(671):致命异常:主
08-01 15:37:44.704:E/AndroidRuntime(671):java.lang.RuntimeException:无法实例化活动组件信息{tip.calculator/tip.calculator.TipCalculator}:java.lang.NullPointerException
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.ActivityThread.access$600(ActivityThread.java:130)
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
08-01 15:37:44.704:E/AndroidRuntime(671):在android.os.Handler.dispatchMessage(Handler.java:99)上
08-01 15:37:44.704:E/AndroidRuntime(671):在android.os.Looper.loop(Looper.java:137)上
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.ActivityThread.main(ActivityThread.java:4745)上
08-01 15:37:44.704:E/AndroidRuntime(671):位于java.lang.reflect.Method.Invokenactive(本机方法)
08-01 15:37:44.704:E/AndroidRuntime(671):位于java.lang.reflect.Method.invoke(Method.java:511)
08-01 15:37:44.704:E/AndroidRuntime(671):在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
08-01 15:37:44.704:E/AndroidRuntime(671):位于com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
8-01 15:37:44.704:E/AndroidRuntime(671):在dalvik.system.NativeStart.main(本机方法)
08-01 15:37:44.704:E/AndroidRuntime(671):由以下原因引起:java.lang.NullPointerException
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.Activity.findViewById(Activity.java:1825)
08-01 15:37:44.704:E/AndroidRuntime(671):在tip.calculator.TipCalculator.(TipCalculator.java:19)
08-01 15:37:44.704:E/AndroidRuntime(671):位于java.lang.Class.newInstanceImpl(本机方法)
08-01 15:37:44.704:E/AndroidRuntime(671):位于java.lang.Class.newInstance(Class.java:1319)
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.Instrumentation.newActivity(Instrumentation.java:1053)上
08-01 15:37:44.704:E/AndroidRuntime(671):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
08-01 15:37:44.704:E/AndroidRuntime(671):。。。还有11个
08-01 15:38:44.993:E/Trace(741):打开跟踪文件时出错:没有这样的文件或目录(2)
08-01 15:38:45.123:E/AndroidRuntime(741):致命异常:主
08-01 15:38:45.123:E/AndroidRuntime(741):java.lang.RuntimeException:无法实例化活动组件信息{tip.calculator/tip.calculator.TipCalculator}:java.lang.NullPointerException
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.ActivityThread.access$600(ActivityThread.java:130)
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
08-01 15:38:45.123:E/AndroidRuntime(741):在android.os.Handler.dispatchMessage(Handler.java:99)上
08-01 15:38:45.123:E/AndroidRuntime(741):在android.os.Looper.loop(Looper.java:137)上
08-01 15:38:45.123:E/AndroidRuntime(741):位于android.app.ActivityThread.main(ActivityThread.java:4745)
08-01 15:38:45.123:E/AndroidRuntime(741):位于java.lang.reflect.Method.Invokenactive(本机方法)
08-01 15:38:45.123:E/AndroidRuntime(741):位于java.lang.reflect.Method.invoke(Method.java:511)
08-01 15:38:45.123:E/AndroidRuntime(741):在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
08-01 15:38:45.123:E/AndroidRuntime(741):位于com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
08-01 15:38:45.123:E/AndroidRuntime(741):在dalvik.system.NativeStart.main(本机方法)
08-01 15:38:45.123:E/AndroidRuntime(741):由以下原因引起:java.lang.NullPointerException
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.Activity.findViewById(Activity.java:1825)
08-01 15:38:45.123:E/AndroidRuntime(741):在tip.calculator.TipCalculator.(TipCalculator.java:19)
08-01 15:38:45.123:E/AndroidRuntime(741):在java.lang.Class.newInstanceImpl(本机方法)中
08-01 15:38:45.123:E/AndroidRuntime(741):位于java.lang.Class.newInstance(Class.java:1319)
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.Instrumentation.newActivity(Instrumentation.java:1053)上
08-01 15:38:45.123:E/AndroidRuntime(741):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
08-01 15:38:45.123:E/AndroidRuntime(741):。。。还有11个
问题在于您用来初始化TipCalculator
类的成员字段的这些行:
EditText myEditField = (EditText) findViewById(R.id.percentText);
final EditText myEditField2 = (EditText) findViewById(R.id.billText);
Button clearButton = (Button) findViewById(R.id.clearButton);
在调用setContentView
之前,不能使用findViewById
。将上述内容替换为:
EditText myEditField;
EditText myEditField2;
Button clearButton;
然后在调用setContentView
后,将其添加到onCreate
的某个位置:
myEditField = (EditText) findViewById(R.id.percentText);
myEditField2 = (EditText) findViewById(R.id.billText);
clearButton = (Button) findViewById(R.id.clearButton);
另外,解释logcat输出的方法是查找最后一行“原因:”并读取堆栈跟踪。之前的所有日志都与此类诊断任务无关。+用于发布实际日志文件。