android numberpicker浮點數

Question

我們的應用程序的用戶應該能夠調整浮點數。此刻，我用一個ArrayAdapter填充了所有可能的值並將其附加到一個微調器上。

該解決方案並不能真正滿足我們的期望，因爲微調框下拉框太高。有沒有更好的辦法？我在看Numberpicker - 但這似乎只適用於整數值。

任何想法？

謝謝！

Answer 1

NumberPicker不僅僅是爲整數。即使你可以用FloatsString等

看到this和了解它。

的教程：

• http://gafurbabu.wordpress.com/2012/03/29/android-number-picker-dialog/

而且我用了NumberPicker早就喜歡這一點，它可能是一些用在這裏發帖：

NumberPicker np; 
    String nums[]= {"Select Fraction","1/64","1/32","3/64","1/16","5/64","3/32","7/64","1/8","9/64","5/32","11/64","3/16","13/64","7/32","15/64","1/4","17/64","9/32","19/64","5/16","21/64","11/32","23/64","3/8","25/64","13/32","27/64","7/16","29/64"}; 

      np = (NumberPicker) findViewById(R.id.np); 

      np.setMaxValue(nums.length-1); 
      np.setMinValue(0); 
      np.setWrapSelectorWheel(false); 
      np.setDisplayedValues(nums); 
      np.setDescendantFocusability(NumberPicker.FOCUS_BLOCK_DESCENDANTS); 

可以使ArrayList任何數據類型並分配它。

Answer 2

另一種解決方案是將兩個號碼字段組合成一個組件。請參閱Money Picker Example。它的優點是你不必爲你的微調器初始化所有可能的double值。

您可能還需要附加特殊數字格式，像「00」，「0123」或其他使用java.lang.String.format()功能。示例是here。

1. 將雙選擇器的XML佈局：

   <LinearLayout 
       xmlns:android = "http://schemas.android.com/apk/res/android" 
       android:layout_width = "fill_parent" 
       android:layout_height = "wrap_content" 
       android:gravity = "center"> 
   
       <NumberPicker 
       android:id = "@+id/integer_picker" 
       android:layout_width = "wrap_content" 
       android:layout_height = "wrap_content" 
       android:layout_gravity = "center"/> 
   
       <TextView 
       android:layout_width = "wrap_content" 
       android:layout_height = "wrap_content" 
       android:layout_gravity = "center" 
       android:padding = "5dp" 
       android:text = "@string/local_separator" 
       android:textSize = "20sp"/> 
   
       <NumberPicker 
       android:id = "@+id/fraction_picker" 
       android:layout_width = "wrap_content" 
       android:layout_height = "wrap_content" 
       android:layout_gravity = "center"/> 
   
       <TextView 
       android:layout_width = "wrap_content" 
       android:layout_height = "wrap_content" 
       android:layout_gravity = "center" 
       android:padding = "5dp" 
       android:text = "@string/measure_unit_sign" 
       android:textSize = "20sp"/> 
   
   </LinearLayout> 
   

2. 添加自定義雙重選擇器類：

   import android.content.Context; 
   import android.view.LayoutInflater; 
   import android.widget.NumberPicker; 
   
   /** 
   * UI component for double (floating point) values. Can be used 
   * for money and other measures. 
   */ 
   public class DoublePicker 
       extends NumberPicker { 
   
       private int decimals; 
       private NumberPicker integerPicker; 
       private NumberPicker fractionPicker; 
   
       public DoublePicker(
       Context context) { 
   
       super(
        context); 
   
        LayoutInflater 
        .from(
         context) 
        .inflate(
         R.layout.double_picker, 
         this); 
   
        integerPicker = 
        (NumberPicker) findViewById(
         R.id.integer_picker); 
   
        fractionPicker = 
        (NumberPicker) findViewById(
         R.id.fraction_picker); 
       } 
   
       public int getDecimals() { 
   
       return decimals; 
       } 
   
       /** 
       * Sets the amount of digits after separator. 
       * 
       * @param decimals Anount of decimals. 
       */ 
       public void setDecimals(final int decimals) { 
   
       this.decimals = decimals; 
   
       this.setFormatter(new DoublePicker.Formatter() { 
   
        @Override 
        public String format(int i) { 
   
        return String.format(
         "%." + decimals + "f", 
         i); 
        } 
       }); 
       } 
   
       public void setValue(double value) { 
   
       integerPicker.setValue((int) value); 
   
       fractionPicker.setValue(
        Integer.valueOf(
        String 
         .valueOf(value) 
         .split(".") 
         [1])); 
       } 
   } 
   

3. 使用新的雙重選擇器組件在活動的xml：

   <com.example.DoublePicker 
       android:id ="@+id/double_picker" 
       android:layout_width ="match_parent" 
       android:layout_height ="wrap_content" />