我怎麼能擴展片段和活動課中的Android

Question

當我伸出Fragment和Activity我得到創作的graphview

我用rootview訪問findViewById

一類錯誤，但我得到GraphView創建錯誤

public class M_oneFragment extends Fragment{ 

public M_oneFragment(){} 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 

     View rootView = inflater.inflate(R.layout.graph_main, container, false); 

     return rootView; 

    // first init data 
    // sin curve 
    int num = 150; 
    GraphViewData[] data = new GraphViewData[num]; 
    double v=0; 
    for (int i=0; i<num; i++) { 
     v += 0.2; 
     data[i] = new GraphViewData(i, Math.sin(v)); 
    } 
    GraphViewSeries seriesSin = new GraphViewSeries("Sinus curve", new GraphViewSeriesStyle(Color.rgb(200, 50, 00), 3), data); 

    // cos curve 
    data = new GraphViewData[num]; 
    v=0; 
    for (int i=0; i<num; i++) { 
     v += 0.2; 
     data[i] = new GraphViewData(i, Math.cos(v)); 
    } 
    GraphViewSeries seriesCos = new GraphViewSeries("Cosinus curve", new GraphViewSeriesStyle(Color.rgb(90, 250, 00), 3), data); 

    // random curve 
    num = 1000; 
    data = new GraphViewData[num]; 
    v=0; 
    for (int i=0; i<num; i++) { 
     v += 0.2; 
     data[i] = new GraphViewData(i, Math.sin(Math.random()*v)); 
    } 
    GraphViewSeries seriesRnd = new GraphViewSeries("Random curve", null, data); 

    // create graph 

    GraphView graphView = new LineGraphView(
     this 
     , "GraphView" 
    ); 

    // add data 
    graphView.addSeries(seriesCos); 
    graphView.addSeries(seriesSin); 
    graphView.addSeries(seriesRnd); 
    // optional - set view port, start=2, size=10 
    graphView.setViewPort(2, 10); 
    graphView.setScalable(true); 
    // optional - legend 
    graphView.setShowLegend(true); 

    LinearLayout layout = (LinearLayout)rootView.findViewById(R.id.layout); 
    layout.addView(graphView); 


    } 

} 

在創建圖表

GraphView graphView = new LineGraphView(
     this 
     , "GraphView" 
    ); 

錯誤

幫我

Answer 1

您需要將上下文傳遞給LineGraphView的構造函數，因此請使用getActivity（）而不是此方法。