更改 Android 微调器第一项背景颜色

Question

我想更改微调器的第一个下拉菜单背景颜色。可能吗？例如，我有 3 个用于性别选择的项目菜单。 1) Select 你的性别 2) 男 3) 女。我想在微调器下拉列表中显示这 3 个项目。我想将第一项的背景更改为浅蓝色，其他两项应为白色。可以吗

Answer 1

使用微调适配器怎么样？

例如，

ArrayList<String> testarray = new ArrayList<String>();
    testarray.add("item0");
    testarray.add("item1");
    testarray.add("item2");
    testarray.add("item3");
    ArrayAdapter<String> spinnerAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_dropdown_item, testarray) {

       @Override      
       public boolean isEnabled(int position) {
           return position != 1;                             
       }

       @Override                
       public boolean areAllItemsEnabled() {
           return false;
       }

       @Override
       public View getDropDownView(int position, View convertView, ViewGroup parent){
           View v = convertView;
           if (v == null) {
               Context mContext = this.getContext();
               LayoutInflater vi = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
               v = vi.inflate(R.layout.row, null);
           }

           TextView tv = (TextView) v.findViewById(R.id.spinnerTarget);
           tv.setText(testarray.get(position));

           switch (position) {
               case 0:
                   tv.setTextColor(Color.RED);  
                   break; 
               case 1:
                   tv.setTextColor(Color.BLUE);
                   break;
               default:
                   tv.setTextColor(Color.BLACK);
                   break;
           }
           return v;  
       }              
    };

    pSpinner.setAdapter(spinnerAdapter);

这是 simple_spinner_dropdown_item.xml 行。

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/spinnerTarget"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="14pt" />

示例代码更改文本颜色。所以你可以尝试改变背景颜色

Answer 2

我为适配器创建了一个单独的 class。在这里

class GenderDropDownAdapter(
    private val mContext: Context,
    private val genderList: ArrayList<String>
) : ArrayAdapter<String>(mContext, android.R.layout.simple_spinner_dropdown_item, genderList) {

    override fun areAllItemsEnabled(): Boolean {
        return false
    }

    override fun isEnabled(position: Int): Boolean {
        return position != 0
    }

    override fun getDropDownView(position: Int, convertView: View?, parent: ViewGroup): View {
        var customView = convertView

        if (customView == null) {
            val mContext = this.context
            val vi: LayoutInflater = mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
            customView = vi.inflate(R.layout.item_gender_dropdown, null)
        }

        val genderTextView: TextView = customView?.findViewById<View>(R.id.gender_dropdown_text) as TextView
        genderTextView.text = genderList[position]

        if (position == 0) {
            genderTextView.setBackgroundColor(mContext.resources.getColor(R.color.colorAccent))
            genderTextView.setTextColor(mContext.resources.getColor(R.color.white))
        } else {
            genderTextView.setTextColor(mContext.resources.getColor(R.color.black))
        }

        return customView
    }

}

并在我的 activity

中使用此适配器

class PersonalDetailActivity : BaseActivity<AuthenticationViewModel>(), AdapterView.OnItemSelectedListener {

    private val genderList = arrayListOf(
        "Select Gender",
        "Male",
        "Female"
    )

    override fun getLayoutResource() = R.layout.activity_personal_detail

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val genderDropDownAdapter = GenderDropDownAdapter(baseContext, genderList)

        gender_spinner.adapter = genderDropDownAdapter
        gender_spinner.onItemSelectedListener = this

    }

    override fun onNothingSelected(parent: AdapterView<*>?) {}

    override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
        gender = when (position) {
            0 -> null
            1 -> "M"
            else -> "F"
        }
    }

}

更改 Android 微调器第一项背景颜色

Change Android Spinner 1st item background color

android

android-spinner