AChartEngine - 来自parse.com的数据图表不会显示

时间:2014-03-25 12:04:30

标签: java android parse-platform achartengine

我想根据parse.com的数据创建构成图表的应用程序。我已经阅读了一些示例和教程,但仍然有显示图表的问题。以下是我的代码:

import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.util.Log;

import com.parse.GetCallback;
import com.parse.ParseException;
import com.parse.ParseObject;
import com.parse.ParseQuery;

import org.achartengine.ChartFactory;
import org.achartengine.GraphicalView;
import org.achartengine.chart.PointStyle;
import org.achartengine.model.XYMultipleSeriesDataset;
import org.achartengine.model.XYSeries;
import org.achartengine.renderer.XYMultipleSeriesRenderer;
import org.achartengine.renderer.XYSeriesRenderer;

import java.util.ArrayList;

public class LineGraph {

    public ArrayList<Integer> dataArray;

    XYMultipleSeriesDataset dataset;
    XYMultipleSeriesRenderer renderer;
    public static boolean ClickEnabled = true;

    public Intent getIntent(Context context) {

        ArrayList<Integer> y = this.dataArray;

        XYSeries seriesY = new XYSeries("Y");
        for (int i = 0; i < y.size(); i++) {
            seriesY.add(i, y.get(i));
        }
        dataset = new XYMultipleSeriesDataset();
        dataset.addSeries(seriesY);

        renderer.setPanEnabled(true, false);
        renderer.setClickEnabled(ClickEnabled);
        renderer.setBackgroundColor(Color.WHITE);
        renderer.setApplyBackgroundColor(true);
        renderer.setChartTitle("Simple data");
        renderer.setAxesColor(Color.BLACK);
        XYMultipleSeriesRenderer mRenderer = new XYMultipleSeriesRenderer();
        XYSeriesRenderer renderer = new XYSeriesRenderer();
        renderer.setColor(Color.RED);
        renderer.setPointStyle(PointStyle.DIAMOND);
        mRenderer.addSeriesRenderer(renderer);

        Intent intent = ChartFactory.getLineChartIntent(context, dataset, mRenderer, "Line Graph Title");
        return intent;
    }

    public void getData() {
        ParseQuery<ParseObject> query = ParseQuery.getQuery("Counters_data");
        query.getInBackground("lxFzCTeOcl", new GetCallback<ParseObject>() {
            public void done(ParseObject parseObject, ParseException e) {

                if (e == null) {
                    String object = parseObject.getString("value");
                    Integer objectValue = Integer.parseInt(object);
                    if (dataArray == null) {
                        dataArray = new ArrayList<Integer>();
                        dataArray.add(objectValue);
                    }
                } else {
                    Log.d("score", "Error: " + e.getMessage());
                }
            }
        });
    }
}

我有如何调用图表:

public void lineGraphHandler(View view) {
        LineGraph line = new LineGraph();
        line.getData();
        Intent lineIntent = line.getIntent(this);
        startActivity(lineIntent);
    }

和XML部分:

<Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/counters"
        android:onClick="lineGraphHandler"
        android:text="Charts"
        android:id="@+id/charts"/>

有我的logcat:

  

03-26 08:42:13.096 1229-1229 / com.example.tst D / dalvikvm:延迟启用   CheckJNI 03-26 08:42:13.487 1229-1229 / com.example.tst D / libEGL:已加载   /system/lib/egl/libEGL_genymotion.so 03-26 08:42:13.491   1229-1229 / com.example.tst D /:HostConnection :: get()新主机   建立连接0xb94f4270,tid 1229 03-26 08:42:13.551   1229-1229 / com.example.tst D / libEGL:已加载   /system/lib/egl/libGLESv1_CM_genymotion.so 03-26 08:42:13.551   1229-1229 / com.example.tst D / libEGL:已加载   /system/lib/egl/libGLESv2_genymotion.so 03-26 08:42:14.035   1229-1229 / com.example.tst W / EGL_genymotion:eglSurfaceAttrib not not not   03-26 08:42:14.039 1229-1229 / com.example.tst   E / OpenGLRenderer:从GradienCache 03-26获取MAX_TEXTURE_SIZE   08:42:14.043 1229-1229 / com.example.tst E / OpenGLRenderer:   MAX_TEXTURE_SIZE:4096 03-26 08:42:14.055 1229-1229 / com.example.tst   E / OpenGLRenderer:从中获取MAX_TEXTURE_SIZE   Caches :: initConstraints()03-26 08:42:14.063 1229-1229 / com.example.tst   E / OpenGLRenderer:MAX_TEXTURE_SIZE:4096 03-26 08:42:14.063   1229-1229 / com.example.tst D / OpenGLRenderer:启用调试模式0   03-26 08:42:50.327 1229-1229 / com.example.tst D / dalvikvm:GC_FOR_ALLOC   释放200K,8%免费2975K / 3228K,暂停10ms,总计13ms 03-26   08:42:51.675 1229-1229 / com.example.tst D / dalvikvm:GC_FOR_ALLOC已释放   431K,14%免费3056K / 3540K,暂停22ms,总计28ms 03-26 08:42:52.043   1229-1229 / com.example.tst W / EGL_genymotion:eglSurfaceAttrib not not not   实施03-26 08:42:53.543 1229-1229 / com.example.tst   I / Choreographer:跳过89帧!该应用程序可能也在做   在其主要线程上做了很多工作。 03-26 08:43:01.747   1229-1229 / com.example.tst D / AndroidRuntime:关闭VM 03-26   08:43:01.747 1229-1229 / com.example.tst W / dalvikvm:threadid = 1:thread   退出未捕获的异常(组= 0xa4d8fb20)03-26 08:43:01.767   1229-1229 / com.example.tst E / AndroidRuntime:FATAL EXCEPTION:main   进程:com.example.tst,PID:1229 java.lang.IllegalStateException:   无法执行活动的方法   android.view.View $ 1.onClick(View.java:3823)at   android.view.View.performClick(View.java:4438)at   android.view.View $ PerformClick.run(View.java:18422)at   android.os.Handler.handleCallback(Handler.java:733)at   android.os.Handler.dispatchMessage(Handler.java:95)at   android.os.Looper.loop(Looper.java:136)at   android.app.ActivityThread.main(ActivityThread.java:5017)at   java.lang.reflect.Method.invokeNative(Native Method)at   java.lang.reflect.Method.invoke(Method.java:515)at   com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:779)   在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)at   dalvik.system.NativeStart.main(Native方法)引起:   java.lang.reflect.InvocationTargetException at   java.lang.reflect.Method.invokeNative(Native Method)at   java.lang.reflect.Method.invoke(Method.java:515)at   android.view.View $ 1.onClick(View.java:3818)at   android.view.View.performClick(View.java:4438)at   android.view.View $ PerformClick.run(View.java:18422)at   android.os.Handler.handleCallback(Handler.java:733)at   android.os.Handler.dispatchMessage(Handler.java:95)at   android.os.Looper.loop(Looper.java:136)at   android.app.ActivityThread.main(ActivityThread.java:5017)
  在java.lang.reflect.Method.invokeNative(Native Method)at   java.lang.reflect.Method.invoke(Method.java:515)at   com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:779)   在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
  at dalvik.system.NativeStart.main(Native Method)引起:   java.lang.NullPointerException at   com.example.tst.LineGraph.getIntent(LineGraph.java:36)at   com.example.tst.MainActivity.lineGraphHandler(MainActivity.java:44)
  在java.lang.reflect.Method.invokeNative(Native Method)at   java.lang.reflect.Method.invoke(Method.java:515)at   android.view.View $ 1.onClick(View.java:3818)at   android.view.View.performClick(View.java:4438)at   android.view.View $ PerformClick.run(View.java:18422)at   android.os.Handler.handleCallback(Handler.java:733)at   android.os.Handler.dispatchMessage(Handler.java:95)at   android.os.Looper.loop(Looper.java:136)at   android.app.ActivityThread.main(ActivityThread.java:5017)
  在java.lang.reflect.Method.invokeNative(Native Method)at   java.lang.reflect.Method.invoke(Method.java:515)at   com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:779)   在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
  在dalvik.system.NativeStart.main(Native Method)03-26 08:43:04.507   1229-1229 / com.example.tst I / Process:发送信号。 PID:1229 SIG:9

我不明白问题所在。我的应用程序启动但是当我按下&#34; chart&#34;时立即崩溃按钮。是问题的数据类型还是因为我误解了什么? 提前谢谢。

我试过这样但仍然崩溃了:

public void done(ParseObject parseObject, ParseException e) {

                if (e == null) {
                    String object = parseObject.getString("value");
                    Integer objectValue = Integer.parseInt(object);
                    if (dataArray == null) {
                        dataArray = new ArrayList<Integer>();
                        dataArray.add(objectValue);

                        ArrayList<Integer> y = dataArray;
                        XYSeries seriesY = new XYSeries("Y");
                        for (int i = 0; i < y.size(); i++) {
                            seriesY.add(i, y.get(i));

                            dataset = new XYMultipleSeriesDataset();
                            dataset.addSeries(seriesY);
                        }

                    }

1 个答案:

答案 0 :(得分:1)

您的getData()异步检索数据。致电dataArray时,getIntent()不会立即初始化。

等待异步操作完成后再使用那里的数据。例如,调用需要done()回调数据的代码。