更改android numberpicker分隔符颜色

Question

我想将上面显示的numberpicker的分隔颜色（蓝色）更改为透明。我尝试了很多类似的东西

number_picker.setDividerDrawable(getResources().getDrawable(R.color.transparent));
number_picker.setShowDividers(NumberPicker.SHOW_DIVIDER_NONE);

我也试过在xml中设置android：divider但是没有一个工作

然后我尝试使用样式设置它，但是当我在我的样式中添加以下条目时，它表示所需的最低版本为14且我的应用程序具有最低版本11

<style name="AppTheme" parent="@android:style/Widget.DeviceDefault.DatePicker">
    <!-- All customizations that are NOT specific to a particular API-level can go here. -->
    <item name="android:divider">@color/transparent</item>
</style>

任何人都可以建议我如何实现这一目标？

Answer 1

这对我有用而不使用反射。

my_layout.xml

<NumberPicker
   ...
   android:theme="@style/DefaultNumberPickerTheme" />

Styles.xml（AppTheme是应用程序中的应用主题）

<style name="DefaultNumberPickerTheme" parent="AppTheme">
        <item name="colorControlNormal">@color/dividerColor</item>
</style>

来自https://stackoverflow.com/a/43985361/1915831

Answer 2

使用Reflection，我们可以实现这一目标

public DatePickerDialog customDatePicker(OnDateSetListener listener, Calendar cal) 
{
    Calendar c;
    if (cal == null) {
        c = Calendar.getInstance();
    } else {
        c = cal;
    }

    int year = c.get(Calendar.YEAR);
    int month = c.get(Calendar.MONTH);
    int day = c.get(Calendar.DAY_OF_MONTH);
    DatePickerDialog newFragment = new DatePickerDialog(this, listener, year, month, day);

    // removes the original topbar:
    newFragment.setTitle(""); 

    // Divider changing:
    DatePicker dpView = newFragment.getDatePicker(); 
    LinearLayout llFirst = (LinearLayout) dpView.getChildAt(0);
    LinearLayout llSecond = (LinearLayout) llFirst.getChildAt(0);
    for (int i = 0; i < llSecond.getChildCount(); i++) {
        NumberPicker picker = (NumberPicker) llSecond.getChildAt(i); // Numberpickers in llSecond
        // reflection - picker.setDividerDrawable(divider); << didn't seem to work.
        Field[] pickerFields = NumberPicker.class.getDeclaredFields();
        for (Field pf : pickerFields) {
            if (pf.getName().equals("mSelectionDivider")) {
                pf.setAccessible(true);
                try {
                    pf.set(picker, getResources().getColor(R.color.green ));
                } catch (IllegalArgumentException e) {
                    e.printStackTrace();
                } catch (NotFoundException e) {
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                }
                break;
            }
        }
    }
    // New top:
    int titleHeight = 90;
    // Container:
    LinearLayout llTitleBar = new LinearLayout(this);
    llTitleBar.setOrientation(LinearLayout.VERTICAL);
    llTitleBar.setBackground(new ColorDrawable(Color.parseColor("#00afac")));
    llTitleBar.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, titleHeight));

    // TextView Title:
    TextView tvTitle = new TextView(this);
    tvTitle.setText("Select Birthday");
    tvTitle.setGravity(Gravity.CENTER);
    tvTitle.setPadding(10, 10, 10, 10);
    tvTitle.setTextSize(24);
    tvTitle.setTextColor(Color.parseColor("#FFFFFF"));
    tvTitle.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, titleHeight-2));
    llTitleBar.addView(tvTitle);

    // View line:
    View vTitleDivider = new View(this);
    vTitleDivider.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, 2));
    vTitleDivider.setBackgroundColor(getResources().getColor(R.color.green));
    llTitleBar.addView(vTitleDivider);

    dpView.addView(llTitleBar);
    FrameLayout.LayoutParams lp = (android.widget.FrameLayout.LayoutParams) llFirst.getLayoutParams();
    lp.setMargins(0, titleHeight, 0, 0);
    return newFragment;
}

//----------------

将此功能称为

customDatePicker(this,calander).show();