Question

嗨，我是androidStudios的新手，但这可能很简单，但我不确定为什么这不起作用。

这是出现的错误：

                                 java.lang.IllegalStateException: Could not execute method for android:onClick
                  at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
                  at android.view.View.performClick(View.java:5610)
                  at android.view.View$PerformClick.run(View.java:22260)
                  at android.os.Handler.handleCallback(Handler.java:751)
                  at android.os.Handler.dispatchMessage(Handler.java:95)
                  at android.os.Looper.loop(Looper.java:154)
                  at android.app.ActivityThread.main(ActivityThread.java:6077)
                  at java.lang.reflect.Method.invoke(Native Method)
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
               Caused by: java.lang.reflect.InvocationTargetException
                  at java.lang.reflect.Method.invoke(Native Method)
                  at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
                  at android.view.View.performClick(View.java:5610) 
                  at android.view.View$PerformClick.run(View.java:22260) 
                  at android.os.Handler.handleCallback(Handler.java:751) 
                  at android.os.Handler.dispatchMessage(Handler.java:95) 
                  at android.os.Looper.loop(Looper.java:154) 
                  at android.app.ActivityThread.main(ActivityThread.java:6077) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) 
               Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x5
                  at android.content.res.Resources.getText(Resources.java:331)
                  at android.support.v7.widget.ResourcesWrapper.getText(ResourcesWrapper.java:52)
                  at android.widget.TextView.setText(TextView.java:4550)
                  at jackiec.downloadmanagerapp.MainActivity.print(MainActivity.java:44)
                  at jackiec.downloadmanagerapp.MainActivity.add(MainActivity.java:38)
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288) 
                  at android.view.View.performClick(View.java:5610) 
                  at android.view.View$PerformClick.run(View.java:22260) 
                  at android.os.Handler.handleCallback(Handler.java:751) 
                  at android.os.Handler.dispatchMessage(Handler.java:95) 
                  at android.os.Looper.loop(Looper.java:154) 
                  at android.app.ActivityThread.main(ActivityThread.java:6077) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)

activty_Main.xml：

    <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    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="jackiec.downloadmanagerapp.MainActivity">

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

        <Button
            android:text="enter"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/Enter"
            android:onClick="add"
            android:layout_centerVertical="true"
            android:layout_centerHorizontal="true" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text="Please enter a download speed:"
            android:ems="10"
            android:id="@+id/speed"
            android:layout_below="@+id/server"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text="Enter the probability of new Regular job:"
            android:ems="10"
            android:layout_below="@+id/probP"
            android:id="@+id/probR"
            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true" />

        <EditText
            android:layout_width="match_parent"
            android:inputType="textPersonName"
            android:text="enter a probability of new premium job:"
            android:ems="10"
            android:id="@+id/probP"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true"
            android:textSize="18sp"
            android:layout_below="@+id/length"
            android:layout_height="wrap_content" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text="Enter the number of servers:"
            android:ems="10"
            android:id="@+id/server"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true"
            android:layout_alignParentTop="true" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPersonName"
            android:text='Please enter a length of time:'
            android:ems="10"
            android:id="@+id/length"
            android:layout_below="@+id/speed"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true" />

        <TextView
            android:text="Ouput"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/Output"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_alignParentRight="true"
            android:layout_alignParentEnd="true"
            android:layout_alignParentBottom="true"
            android:layout_below="@+id/Enter" />
    </LinearLayout>

</RelativeLayout>

MainActivty.java：

    public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        output= (TextView) this.findViewById(R.id.Output);
        server =(EditText) this.findViewById(R.id.server);
        length = (EditText) this.findViewById(R.id.length);
        speed = (EditText) this.findViewById(R.id.speed);
        probR = (EditText) this.findViewById(R.id.probR);
        probP = (EditText)this.findViewById(R.id.probP);
    }
    TextView output;
    EditText server;
    EditText length;
    EditText speed;
    EditText probP;
    EditText probR;

    public void add(View view)
    {

       int nServer= Integer.parseInt(server.getText().toString());
        int nLength = Integer.parseInt(length.getText().toString());
        int nSpeed = Integer.parseInt(speed.getText().toString());
        int p= Integer.parseInt(probP.getText().toString());
        int r = Integer.parseInt(probR.getText().toString());
        int addAll = nServer+nLength+nSpeed+p+r;
        print(addAll);


    }
      public void print(int a)
    {
        output.setText(a);
    }



}

我认为这可能是在做Integer.parse（）时出错了。谢谢你的帮助。

Answer 1

你是对的，它确实与Caused by: java.lang.NumberFormatException: For input string: "1Enter the number of servers:"有关。您可以通过检查堆栈跟踪中的以下行来确定这一点：

Integer.parse() 这意味着您的EditText方法试图将“1输入服务器数量：”转换为整数，这显然是不正确的。现在仔细查看您的代码，看起来您的“服务器”int nServer= Integer.parseInt(server.getText().toString());字段包含文本“输入服务器数量：”。代码中的这一行：

server.getText().toString()

从“server”字段获取文本，并尝试将其转换为整数。您可能输入值“1”，但未清除该字段中的默认文本。这导致Integer.parse()的值为“1Integer服务器数量：”。这意味着NumberFormatException将抛出NumberFormatException，因为它不是有效整数。你应该做的是处理这个try { int nServer= Integer.parseInt(server.getText().toString()); } catch (NumberFormatException e) { //alert the user that the number they tried to enter was invalid }，因为你不能总是保证你的用户会输入一个有效的号码。这看起来像是：

public boolean remove(T o)

Answer 2

对于您设置文本的所有EditText。尝试为所有edittexts使用提示而不是文本

android:text="Enter the number of servers:"

到

android:hint="Enter the number of servers:"

并将所有Interger解析放在try catch块

中

try {
  int nServer= Integer.parseInt(server.getText().toString());
    int nLength = Integer.parseInt(length.getText().toString());
    int nSpeed = Integer.parseInt(speed.getText().toString());
    int p= Integer.parseInt(probP.getText().toString());
    int r = Integer.parseInt(probR.getText().toString());
    int addAll = nServer+nLength+nSpeed+p+r;
    print(addAll);
} catch (NumberFormatException e) {
   //alert the user that the number they tried to enter was invalid
 }

Answer 3

引起：java.lang.NumberFormatException：对于输入字符串：“1Enter 服务器数量：“

您只能将数字解析为整数。文本字段中有字符串输入，名为server ..

AndroidStudios onClick错误

3 个答案: