java - 尝试使用适配器内的变量设置背景颜色时出现 StringIndexOutofBoundsException

Question

当我尝试放置一个带有十六进制颜色的字符串变量来设置我的适配器类上的 edittext 的 setbackgroundcolor(Color.parseColor(String s)) 时，它说

StringIndexOutofBoundsException, length = 0, index = 0.

当我手动将字符串插入到 parseColor 中时，例如 parseColor("#ffffff");，它起作用了!

我的适配器类:

public class TasksAdapter extends ArrayAdapter<Tasks> {
    private Context sContext;
    private List<Tasks> taskData = new ArrayList<>();
    public TasksAdapter(@NonNull Context context, @SuppressLint("SupportAnnotationUsage") @LayoutRes ArrayList<Tasks> list){
        super(context, 0, list);
        sContext = context;
        taskData = list;
    }
    @NonNull
    @Override
    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent){
        View listItem = convertView;
        if(listItem == null)
            listItem = LayoutInflater.from(sContext).inflate(R.layout.item_tasks, parent,false);
        final Tasks presenteTask = taskData.get(position);
        TextView taskTitle = (TextView) listItem.findViewById(R.id.tasksTitle);
        taskTitle.setText(presenteTask.getTitle());
        EditText taskColor = (EditText) listItem.findViewById(R.id.taskColor);
        taskColor.setBackgroundColor(Color.parseColor(presenteTask.getHexaColor()));
        return listItem;
    }
}

错误:

E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.mylcm, PID: 672 java.lang.StringIndexOutOfBoundsException: length=0; index=0 at java.lang.String.charAt(Native Method) at android.graphics.Color.parseColor(Color.java:1384) at com.example.mylcm.Utils.Adapters.TasksAdapter.getView(TasksAdapter.java:49) at android.widget.AbsListView.obtainView(AbsListView.java:2365) at android.widget.ListView.makeAndAddView(ListView.java:2052) at android.widget.ListView.fillDown(ListView.java:786) at android.widget.ListView.fillFromTop(ListView.java:847) at android.widget.ListView.layoutChildren(ListView.java:1826) at android.widget.AbsListView.onLayout(AbsListView.java:2164) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1791) at android.widget.LinearLayout.layoutHorizontal(LinearLayout.java:1780) at android.widget.LinearLayout.onLayout(LinearLayout.java:1546) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1083) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323) at android.widget.FrameLayout.onLayout(FrameLayout.java:261) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1791) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1635) at android.widget.LinearLayout.onLayout(LinearLayout.java:1544) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323) at android.widget.FrameLayout.onLayout(FrameLayout.java:261) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1791) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1635) at android.widget.LinearLayout.onLayout(LinearLayout.java:1544) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323) at android.widget.FrameLayout.onLayout(FrameLayout.java:261) at com.android.internal.policy.DecorView.onLayout(DecorView.java:761) at android.view.View.layout(View.java:19659) at android.view.ViewGroup.layout(ViewGroup.java:6075) at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2496) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2212) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1392) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6752) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:911) at android.view.Choreographer.doCallbacks(Choreographer.java:723) at android.view.Choreographer.doFrame(Choreographer.java:658) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:897) at android.os.Handler.handleCallback(Handler.java:790) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6494) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

Answer 1

内部getView()的TaskAdapter您的其中之一taskData项目返回空hexaColor在执行presenteTask.getHexaColor()期间。尝试下面的代码，它将阻止您的应用程序被强制关闭，并且您将获得导致 exception 的项目的位置。里面catch .

public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent){
    View listItem = convertView;
    if(listItem == null)
        listItem = LayoutInflater.from(sContext).inflate(R.layout.item_tasks, parent,false);

    try {
        final Tasks presenteTask = taskData.get(position);
        TextView taskTitle = (TextView) listItem.findViewById(R.id.tasksTitle);
        taskTitle.setText(presenteTask.getTitle());
        EditText taskColor = (EditText) listItem.findViewById(R.id.taskColor);
        taskColor.setBackgroundColor(Color.parseColor(presenteTask.getHexaColor()));
    } catch(Exception ex) {
        Log.v(TasksAdapter.class.getSimpleName(), "Exception at: " + position);
    }

    return listItem;
}