这次主要是悬系的下拉框Spinner和数字转轮NumberPicker的使用。先分析相关的用到的知识点。

在Android中,用string-array是一种简单的提取XML资源文件数据的方法。
  例子如下:

  把相应的数据放到values文件夹的arrays.xml文件里

复制代码
<?xml version="1.0" encoding="utf-8"?>
  <resources>
      <string-array name="city">
          <item>丰台区</item>
          <item>石景山区</item>
          <item>海淀区</item>
          <item>漳州市</item>
          <item>朝阳区</item>
      </string-array>
  </resources>
复制代码

  然后在Activity里,直接使用
  Resources res =getResources();
  String[] city=res.getStringArray(R.array.city);
  即可取得string-array name=”city”下的所有item数据,简单又方便的一种方法

对于

private AdapterView.OnItemSelectedListener spnSexOnItemSelected=new AdapterView.OnItemSelectedListener() {}
中的相关参数的知识点:
  1. parent 发生选中事件的 AbsListView。 
  2. view AbsListView 中被选中的视图。 
  3. position 视图在一览中的位置(索引)。 
  4. id 被点击条目的行 ID。
private AdapterView.OnItemSelectedListener spnSexOnItemSelected=new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
msSex=parent.getSelectedItem().toString();
}是用来确定下拉框中对应的被选中的哪一项。
具体相关的实现代码如下:
MainActivity.java
package com.example.myapplicationhome;
import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.NumberPicker;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Spinner;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    private NumberPicker mNumPickerAge;
    private Button mBtnOk;
    private TextView mTxtR,mTxtAge;
    private Spinner mSpnSex;
    private String msSex;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mTxtAge=(TextView)findViewById(R.id.txtAge);
        mTxtAge.setText("25");

        mNumPickerAge=(NumberPicker)findViewById(R.id.numPickerAge);

        mNumPickerAge.setMinValue(0);
        mNumPickerAge.setMaxValue(200);
        mNumPickerAge.setValue(25);

        mNumPickerAge.setOnValueChangedListener(numPickerAgeOnValueChange);

        mBtnOk=(Button)findViewById(R.id.btnOk);
        mTxtR=(TextView)findViewById(R.id.txtR);

        mBtnOk.setOnClickListener(btnOkOnClick);
        mSpnSex=(Spinner)findViewById(R.id.spnSex);
        mSpnSex.setOnItemSelectedListener(spnSexOnItemSelected);

    }

    private View.OnClickListener btnOkOnClick =new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            int iAge=mNumPickerAge.getValue();
            String strSug=getString(R.string.result);

            if(msSex.equals(getString(R.string.sex_male)))
            {
                if(iAge<28)
                    strSug+=getString(R.string.sug_not_hurry);
                else if(iAge>33)
                    strSug+=getString(R.string.sug_get_married);
                else
                    strSug+=getString(R.string.sug_find_couple);
            }
            else
            {
                if(iAge<25)
                    strSug+=getString(R.string.sug_not_hurry);
                else if(iAge>30)
                    strSug+=getString(R.string.sug_get_married);
                else
                    strSug+=getString(R.string.sug_find_couple);
            }
            mTxtR.setText(strSug);
        }
    };

    private AdapterView.OnItemSelectedListener spnSexOnItemSelected=new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            msSex=parent.getSelectedItem().toString();
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    };
    private NumberPicker.OnValueChangeListener numPickerAgeOnValueChange=new NumberPicker.OnValueChangeListener() {
        @Override
        public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
            mTxtAge.setText(String.valueOf(newVal));
        }
    };
}

strings.xml

<resources>
    <string name="app_name">婚姻建议程序</string>
    <string name="sex">性别:</string>
    <string name="age">年龄:</string>
    <string name="btn_ok">确定</string>
    <string name="result">最终诊断结果:</string>
    <string name="edt_age_hint">(输入年龄)</string>
    <string name="sug_not_hurry">还不急</string>
    <string name="sug_get_married">你废了!</string>
    <string name="sug_find_couple">开始找对象。</string>
    <string name="sex_male"></string>
    <string-array name="sex_list">
        <item></item>
        <item></item>
    </string-array>
    <string name="spn_sex_list_prompt">请选择性别</string>

</resources>

activaty_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/sex"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/sex"
        android:textSize="25sp" />
    <Spinner
        android:id="@+id/spnSex"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:entries="@array/sex_list"
        android:spinnerMode="dialog"
        android:prompt="@string/spn_sex_list_prompt" />
    <TextView
        android:id="@+id/age"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/age"
        android:textSize="25sp" />
    <TextView
        android:id="@+id/txtAge"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="0"
        android:textSize="25sp" />
    <NumberPicker
        android:id="@+id/numPickerAge"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="left" />
    <Button
        android:id="@+id/btnOk"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:background="#4CAF50"
        android:text="@string/btn_ok" />

    <TextView
        android:id="@+id/txtR"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/result"
        android:textSize="25sp" />
</LinearLayout>

具体的实验结果如下:

 

 

 

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本文链接:https://www.cnblogs.com/dazhi151/p/12243406.html