Question

我现在正在学习android，我根据这本书写了一些简单的代码。

我创建一个名为Chapter03_ResourceActivity的android项目，然后在res / xml /文件夹中创建 test.xml ，内容如下：

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <customer name = "first_name" age = "1" email = "first_name@xml.com" />
    <customer name = "second_name" age = "2" email = "second_name@xml.com" />
</resources>

并在 Chapter03_ResourceActivity.java （src / com.app.MainActivity / Chapter03_ResourceActivity.java）中键入代码，如下所示：

package com.app.MainActivity;

import org.xmlpull.v1.XmlPullParserException;

import android.app.Activity;
import android.content.res.XmlResourceParser;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class Chapter03_ResourceActivity extends Activity {
    /** Called when the activity is first created. */

    private Button myButton;
    private TextView myTextView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Button myButton = (Button)findViewById(R.id.btn_xml);
        final TextView myTextView = (TextView)findViewById(R.id.text_xml);

        myButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
            StringBuilder sb = new StringBuilder();
            XmlResourceParser xrp = getResources().getXml(R.xml.test);
            int counter = 0;
            try {
                while(xrp.getEventType() != XmlResourceParser.END_DOCUMENT) {
                    if(xrp.getEventType() == XmlResourceParser.START_TAG) {
                        String name = xrp.getName();
                        if(name.equals("customer")) {
                            counter ++;
                            sb.append(counter + " Customer" + "\n");
                            sb.append(xrp.getAttributeValue(0) + "\n");
                            sb.append(xrp.getAttributeValue(1) + "\n");
                            sb.append(xrp.getAttributeValue(2) + "\n\n");
                        } 
                        xrp.next();
                    }
                } 
            myTextView.setText(sb.toString());    <<--Here Eclipse mark an error. 
                catch(XmlPullParserException e) {
                    e.printStackTrace();
                }
            }   
            }
        });           <<--Here Eclipse mark another error.
    }
}

代码中标记了两个错误。我试图自己解决它，但原谅我的沉闷，我找不到它。我多次计算“{”和“}”的数量，并发现它们是正确的。也许我真的错了？或者我不知道的事情犯了这个错误？任何帮助表示赞赏。

Answer 1

catch(XmlPullParserException e) {
    e.printStackTrace();
}

应该是：

} catch(XmlPullParserException e) {
    e.printStackTrace();

不是数量导致你的悲伤，只是放置。您的catch实际上在<{1}}区块内，而不是紧接在它之后。

Answer 2

你用{开始你的尝试块但是你永远不会用}关闭它。所以你应该在你的catch语句之前添加一个}。

Answer 3

将eclipse标记为错误的行不在任何代码块中......

在捕获之前添加一个闭合的卷曲支撑，并以这种方式移动该行：

public class Chapter03_ResourceActivity extends Activity {
    /** Called when the activity is first created. */

    private Button myButton;
    private TextView myTextView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Button myButton = (Button)findViewById(R.id.btn_xml);
        final TextView myTextView = (TextView)findViewById(R.id.text_xml);

        myButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
            StringBuilder sb = new StringBuilder();
            XmlResourceParser xrp = getResources().getXml(R.xml.test);
            int counter = 0;
            try {
                while(xrp.getEventType() != XmlResourceParser.END_DOCUMENT) {
                    if(xrp.getEventType() == XmlResourceParser.START_TAG) {
                        String name = xrp.getName();
                        if(name.equals("customer")) {
                            counter ++;
                            sb.append(counter + " Customer" + "\n");
                            sb.append(xrp.getAttributeValue(0) + "\n");
                            sb.append(xrp.getAttributeValue(1) + "\n");
                            sb.append(xrp.getAttributeValue(2) + "\n\n");
                        } 
                        xrp.next();
                    }

                } 
                 myTextView.setText(sb.toString());    <<--Now is fine
                } catch(XmlPullParserException e) {
                    e.printStackTrace();
                }
            }   
            }
        });
    }
}

令牌“}”上的语法错误，但我真的找不到它

3 个答案: