如何传递ArrayList< String>转到另一项活动并将其转换为两倍

问题描述

伙计们，我正在构建一个应用程序，该应用程序通过从mysql数组中请求的mysql值生成一些动态图.

Hey guys i am building an app which produces a dynamic graph through some values i get from mysql which are requested in json array.

我的代码是:

Intent i = this.getActivity().getIntent();
        HashMap<String, String> hashMap = (HashMap<String, String>) i.getSerializableExtra("stockInfo");
        name = i.getStringExtra("name");
        ball = i.getStringExtra("price");
        final ArrayList<String> myItems = new ArrayList<String>(hashMap.values());
        myItems.remove(name);
        myItems.remove(ball);
Button buttonLiveGraph = (Button)rootView.findViewById(R.id.buttonlive);
        buttonLiveGraph.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(getActivity().getApplicationContext(), LiveGraph.class);
                intent.putExtra("stockprices", myItems.toString());
                getActivity().startActivity(intent);
            }
        });

在LiveGraph活动中，我得到如下意图值:

and in LiveGraph activity i get the intent values like so:

import org.achartengine.GraphicalView;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

public class LiveGraph extends Activity {

    private static GraphicalView view;
    private LiveGraphClass live = new LiveGraphClass();
    private static Thread thread;


    private String myPrices;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_live_graph);
        Intent i = this.getIntent();
        myPrices = i.getStringExtra("stockprices");
        thread = new Thread(){
            @Override
            public void run() {
                for (double i = 0; i < 15; i++) {
                    try {
                        Thread.sleep(3000);
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    Point p = getDataFromReceiver(i);
                    live.addNewPoints(p);
                    view.repaint();
                }

            }
        };
        thread.start();
    }

    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();
        view = live.getView(this);
        setContentView(view);
    }

    public Point getDataFromReceiver(double x){
        return new Point(x, Double.parseDouble(myPrices));
    }

}

我的LiveGraphClass活动:

My LiveGraphClass activity:

public class LiveGraphClass {


    private GraphicalView view;
    private TimeSeries dataset = new TimeSeries("Rain Fall");
    private XYMultipleSeriesDataset mDataset = new XYMultipleSeriesDataset();
    private XYSeriesRenderer renderer = new XYSeriesRenderer();
    private XYMultipleSeriesRenderer mRenderer = new XYMultipleSeriesRenderer();

    public LiveGraphClass(){
        mDataset.addSeries(dataset);
        mRenderer.addSeriesRenderer(renderer);
        renderer.setColor(Color.WHITE);
        renderer.setPointStyle(PointStyle.SQUARE);
        renderer.setFillPoints(true);
        mRenderer.setExternalZoomEnabled(true);
        mRenderer.setZoomButtonsVisible(true);
        mRenderer.setBackgroundColor(Color.BLACK);
        mRenderer.setApplyBackgroundColor(true);
        mRenderer.setZoomEnabled(true);
        mRenderer.setYTitle("Range");
        mRenderer.setXTitle("Values");
    }

    public GraphicalView getView(Context context){

        view = ChartFactory.getLineChartView(context, mDataset, mRenderer);
        return view;
    }

    public void addNewPoints(Point p){
        dataset.add(p.getX(), p.getY());
    }
}

我的积分活动

public class Point {

    private double x;
    private double y;
    public Point(double x, double y) {
        super();
        this.x = x;
        this.y = y;
    }
    public double getX() {
        return x;
    }
    public double getY() {
        return y;
    }


}

我得到这个错误

03-25 12:20:09.515: E/AndroidRuntime(1671): java.lang.NumberFormatException: Invalid double: "[9.32, 5.22, 10.201, 2.54, 3.214, 1.02, 0.21, 0.147, 7.01, 0.365, 8.23, 0.254, 8.89, 0.155, 4.32]"
03-25 12:20:09.515: E/AndroidRuntime(1671):     at java.lang.StringToReal.invalidReal(StringToReal.java:63)
03-25 12:20:09.515: E/AndroidRuntime(1671):     at java.lang.StringToReal.parseDouble(StringToReal.java:269)
03-25 12:20:09.515: E/AndroidRuntime(1671):     at java.lang.Double.parseDouble(Double.java:295)

有人可以帮我解决这个问题吗?为什么会发生这种情况，因为我通过意图发送了双打并且我得到了双打，所以我尝试生成一个双图?

Can anybody help me solve this problem?? why is that happening since i send doubles through intent and i get doubles so i try to produce a double graph??

我的php代码:

<?php
try {
    $handler = new PDO(this is not available);
    $handler->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch (Exception $e) {
    echo $e->getMessage();
    die();
}

$query = $handler->query('SELECT * FROM metoxes');
$records = array();
$records = $query->fetchAll(PDO::FETCH_ASSOC);
$json['metoxes'] = $records;
echo json_encode($json);
?>

提前谢谢！任何帮助都会受到欢迎和赞赏.

Thanks in advance! any help will be much welcomed and appreaciated.

推荐答案

您以字符串[]的形式发送Intent，但尝试像字符串一样接收它，这是不可能的.而是这样做:

You send the Intent as a string[] but you trying to receive it like as a String which is not possible. So do this instead:

像这样修改LiveGraph类:

Modify your LiveGraph class like this:

public class LiveGraph extends ActionBarActivity {

    private static GraphicalView view;
    private LiveGraphClass live = new LiveGraphClass();
    private static Thread thread;
    static String[] myPrices;
    double point;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_live_graph);
        Toolbar tb = (Toolbar) findViewById(R.id.toolBar);
        setSupportActionBar(tb);
        Intent i = this.getIntent();
        myPrices = i.getStringArrayExtra("stockprices");
        thread = new Thread() {
            @Override
            public void run() {
                for (int i = 0; i < myPrices.length; i++) {
                    try {
                        Thread.sleep(800);
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    Point p = new Point(i, Double.parseDouble(myPrices[i]));
                    live.addNewPoints(p);
                    view.repaint();
                }
            }
        };
        thread.start();
    }

    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();
        view = live.getView(this);
        setContentView(view);
    }
}

希望有帮助！

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