如何在LinearLayout上更新片段的視圖

Question

我有一個片段GraphFragment，它在圖形上使用GraphView繪制我需要的所有數據。 我想為用戶提供更改GraphView的網格顏色的選項，但是當我嘗試更新視圖時，它似乎不起作用（沒有任何更改）。 setGridColor函數依賴於用戶按下的特定列表視圖索引。

public class GraphFragment extends Fragment {

    private GraphView graphView;    
    LinearLayout layout;

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

        ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.graph_fragment, container, false);

        //Initialise the glucose level graph
        graphView = new LineGraphView(this.getActivity(), "Blood Glucose (mmol/l)");  

        graphView.getGraphViewStyle().setVerticalLabelsWidth(40);

        //Add the test data
        graphView.addSeries(testSeries);

        layout = (LinearLayout) rootView.findViewById(R.id.graph1);  
        layout.addView(graphView);
    }

    public void setGridColor (int position){
        if(position==0){
            //graphView = new LineGraphView(this.getActivity(), "Blood Glucose (mmol/l)");
            layout.removeView(graphView);
            graphView.getGraphViewStyle().setGridColor(Color.RED);
            layout.addView(graphView);              
        }
        if(position==1){
            //graphView = new LineGraphView(this.getActivity(), "Blood Glucose (mmol/l)");
            layout.removeView(graphView);
            graphView.getGraphViewStyle().setGridColor(Color.BLUE);
            layout.addView(graphView);
        }
        if(position==2){
            //graphView = new LineGraphView(this.getActivity(), "Blood Glucose (mmol/l)");
            layout.removeView(graphView);
            graphView.getGraphViewStyle().setGridColor(Color.GREEN);
            layout.addView(graphView);
        }
    }
}

Answer 1

更改后，嘗試運行graphView.invalidate() 。