为什么我的图表没有显示?

Why is my graph not showing up?

我正在尝试在我的项目中使用 MPAndroidChart 库。这就是我的布局和 Activity 代码。当我 运行 这样做时,它没有在我的布局中显示任何内容。我确定我错过了一些非常小的东西。但它是什么?为什么它没有出现真的很烦我

graph_activity.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin">

    <com.github.mikephil.charting.charts.BarChart
        android:id="@+id/chart"
        android:visibility="visible"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</RelativeLayout>

GraphTestActivity.java

public class GraphTestActivity extends ActionBarActivity {
    private LineChart responseTimeChart;

    @Override
    public void onCreate(Bundle savedInstanceState, PersistableBundle persistentState) {
        super.onCreate(savedInstanceState, persistentState);
        setContentView(R.layout.graph_activity);
        showBarChart();
    }

    private void showBarChart() {
        BarChart chart = (BarChart) findViewById(R.id.chart);

        BarData data = new BarData(getXAxisValues(), getDataSet());
        chart.setData(data);
        chart.setDescription("My Chart");
        chart.animateXY(2000, 2000);
        chart.invalidate();
    }

    private ArrayList<BarDataSet> getDataSet() {
        ArrayList<BarDataSet> dataSets = null;

        ArrayList<BarEntry> valueSet1 = new ArrayList<>();
        BarEntry v1e1 = new BarEntry(110.000f, 0); // Jan
        valueSet1.add(v1e1);
        BarEntry v1e2 = new BarEntry(40.000f, 1); // Feb
        valueSet1.add(v1e2);
        BarEntry v1e3 = new BarEntry(60.000f, 2); // Mar
        valueSet1.add(v1e3);
        BarEntry v1e4 = new BarEntry(30.000f, 3); // Apr
        valueSet1.add(v1e4);
        BarEntry v1e5 = new BarEntry(90.000f, 4); // May
        valueSet1.add(v1e5);
        BarEntry v1e6 = new BarEntry(100.000f, 5); // Jun
        valueSet1.add(v1e6);

        ArrayList<BarEntry> valueSet2 = new ArrayList<>();
        BarEntry v2e1 = new BarEntry(150.000f, 0); // Jan
        valueSet2.add(v2e1);
        BarEntry v2e2 = new BarEntry(90.000f, 1); // Feb
        valueSet2.add(v2e2);
        BarEntry v2e3 = new BarEntry(120.000f, 2); // Mar
        valueSet2.add(v2e3);
        BarEntry v2e4 = new BarEntry(60.000f, 3); // Apr
        valueSet2.add(v2e4);
        BarEntry v2e5 = new BarEntry(20.000f, 4); // May
        valueSet2.add(v2e5);
        BarEntry v2e6 = new BarEntry(80.000f, 5); // Jun
        valueSet2.add(v2e6);

        BarDataSet barDataSet1 = new BarDataSet(valueSet1, "Brand 1");
        barDataSet1.setColor(Color.rgb(0, 155, 0));
        BarDataSet barDataSet2 = new BarDataSet(valueSet2, "Brand 2");
        barDataSet2.setColors(ColorTemplate.COLORFUL_COLORS);

        dataSets = new ArrayList<>();
        dataSets.add(barDataSet1);
        dataSets.add(barDataSet2);
        return dataSets;
    }

    private ArrayList<String> getXAxisValues() {
        ArrayList<String> xAxis = new ArrayList<>();
        xAxis.add("JAN");
        xAxis.add("FEB");
        xAxis.add("MAR");
        xAxis.add("APR");
        xAxis.add("MAY");
        xAxis.add("JUN");
        return xAxis;
    }
}

自版本 22.1.0 起,class ActionBarActivity 已弃用。你应该使用 AppCompatActivity.

也许这可能是某些内容未显示的问题?您确定您的问题与图书馆有关吗? 你有没有添加例如将 TextView 添加到 .xml 文件并验证它是否显示?

没关系。弄清楚我使用的是 onCreate(Bundle savedInstanceState, PersistableBundle persistentState) 而不是 onCreate(Bundle savedInstanceState)