java - Android Jsoup HTML解析

Question

我对android有点陌生，我尝试使用jsoup来解析html页面以从页面收集一些信息。我想使用名为 loadwebsite 的方法通过弹出窗口(altertbox)插入网址:

private void loadWebsite(){
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("Inserisci url sito");

    final EditText input = new EditText(this);
    input.setInputType(InputType.TYPE_CLASS_TEXT);
    builder.setView(input);
    builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            linkurl = input.getText().toString();
            //linkurl="https://"+linkurl;
            url123.setText("https://"+linkurl.toString());
        }
    });
    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();
        }
    });

    builder.show();



}

和一个名为 getsiteinfo() 的方法

private void getinfoWebsite(){

    new Thread(new Runnable() {
        @Override
        public void run() {
           final StringBuilder builder = new StringBuilder();

            try {
                Document  doc = Jsoup.connect(linkurl).get();
                String title = doc.title();
                Element image = doc.select("img").first();
                String imgSrc = image.absUrl("src");
                InputStream in = new java.net.URL(imgSrc).openStream();
                bitmap = BitmapFactory.decodeStream(in);
                builder.append(title).append("\n");
            } catch (IOException e){
             builder.append("Error :").append(e.getMessage()).append("\n");
            }
            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    result.setText(builder.toString());
                }
            });
        }
    }).start();

}

问题是，当我尝试通过文本框传递网址时，我收到该错误:

03-26 17:22:16.826 26651-26840/it.uninsubria.pdm.htmlparsingjsoup E/AndroidRuntime: FATAL EXCEPTION: Thread-8
                                                                                Process: it.uninsubria.pdm.htmlparsingjsoup, PID: 26651
                                                                                java.lang.IllegalArgumentException: Must supply a valid URL
                                                                                    at org.jsoup.helper.Validate.notEmpty(Validate.java:102)
                                                                                    at org.jsoup.helper.HttpConnection.url(HttpConnection.java:72)
                                                                                    at org.jsoup.helper.HttpConnection.connect(HttpConnection.java:36)
                                                                                    at org.jsoup.Jsoup.connect(Jsoup.java:73)
                                                                                    at it.uninsubria.pdm.htmlparsingjsoup.MainActivity$3.run(MainActivity.java:78)
                                                                                    at java.lang.Thread.run(Thread.java:764)

这里是完整的代码:

import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.AsyncTask;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.InputType;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.parser.Tag;
import org.jsoup.select.Elements;

import java.io.IOException;
import java.io.InputStream;

public class MainActivity extends AppCompatActivity {
    private Button getBtn;
    private TextView result;
    private ImageView img;
    private Bitmap bitmap;
    private Button button2;
    private String linkurl = "";
    private TextView url123;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        result = (TextView) findViewById(R.id.result);
        img= (ImageView) findViewById(R.id.image2);
        url123 =(TextView)findViewById(R.id.url123);

        getBtn =(Button) findViewById(R.id.button2);              //
        getBtn.setOnClickListener(new View.OnClickListener() {    // Pulsante "open website
            @Override                                             //
            public void onClick(View v) {
                openWebsite();

            }

        });
        getBtn =(Button) findViewById(R.id.getBtn);
        getBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                loadWebsite();
                getinfoWebsite();
                img.setImageBitmap(bitmap);

            }
        });
    }




    //////////////////////////////////////////// -------------------METHODS------------------////////////////////////////////////////////

    private void getinfoWebsite(){

        new Thread(new Runnable() {
            @Override
            public void run() {
               final StringBuilder builder = new StringBuilder();

                try {
                    Document  doc = Jsoup.connect(linkurl).get();
                    String title = doc.title();
                    Element image = doc.select("img").first();
                    String imgSrc = image.absUrl("src");
                    InputStream in = new java.net.URL(imgSrc).openStream();
                    bitmap = BitmapFactory.decodeStream(in);
                    builder.append(title).append("\n");
                } catch (IOException e){
                 builder.append("Error :").append(e.getMessage()).append("\n");
                }
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        result.setText(builder.toString());
                    }
                });
            }
        }).start();

    }
    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    private void openWebsite(){
        Uri uriUrl = Uri.parse(String.valueOf(linkurl));
        Intent launchBrowser = new Intent(Intent.ACTION_VIEW, uriUrl);
        startActivity(launchBrowser);
    }


    //////////////////////////////////////////////////////////////////////////////////////////////////////////////
   //pop-up text per caricare link url
    private void loadWebsite(){
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Inserisci url sito");

        final EditText input = new EditText(this);
        input.setInputType(InputType.TYPE_CLASS_TEXT);
        builder.setView(input);
        builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                linkurl = input.getText().toString();
                //linkurl="https://"+linkurl;
                url123.setText("https://"+linkurl.toString());
            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
            }
        });

        builder.show();



    }
}

Answer 1

该错误表明您传递给 Jsoup.connect 的参数无效(空)。看起来您创建了 onClick 监听器来设置 linkurl 的值，但您立即开始解析线程，即不等待设置 linkurl 值。例如，您可以通过在 getinfoWebsite() 内的 run 方法的开头插入以下代码来延迟代码的执行: while(linkurl.isEmpty()) { Thread.sleep(1000);}