实现功能

实现日期和时间选择的对话框，具体效果可看下图(以日期为例)

具体代码

1 日期对话框

1.1 xml

1.2 Java

package com.example.learn;
import androidx.appcompat.app.AppCompatActivity;
import android.app.DatePickerDialog;
import android.os.Bundle;
import android.view.View;
import android.widget.DatePicker;
import android.widget.TextView;
import java.util.Calendar;
public class DatePickerActivity extends AppCompatActivity implements View.OnClickListener, DatePickerDialog.OnDateSetListener {
    private TextView tv;
    private DatePicker dp;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_date_picker);
        findViewById(R.id.btn_ok).setOnClickListener(this);
        findViewById(R.id.btn_date).setOnClickListener(this);
        tv=findViewById(R.id.tv_date);
        dp = findViewById(R.id.datePicker);
    }
    @Override
    public void onClick(View view) {
        switch(view.getId()){
            case R.id.btn_ok:
                String desc=String.format("%d年%d月%d日",dp.getYear(),dp.getMonth()+1,dp.getDayOfMonth());
                tv.setText(desc);
                break;
            case R.id.btn_date:
                //获取当前时间
                Calendar now = Calendar.getInstance();
                DatePickerDialog dpd = new DatePickerDialog(this,this,now.get(Calendar.YEAR),now.get(Calendar.MONTH),now.get(Calendar.DAY_OF_MONTH));
                //显示
                dpd.show();
                break;
        }
    }
    @Override
    public void onDateSet(DatePicker datePicker, int i, int i1, int i2) {
        String desc=String.format("%d年%d月%d日",i,i1+1,i2);
        tv.setText(desc);
    }
}

2 时间选择对话框

2.1 xml

2.2 java

package com.example.learn;
import androidx.appcompat.app.AppCompatActivity;
import android.app.TimePickerDialog;
import android.os.Bundle;
import android.view.View;
import android.widget.DatePicker;
import android.widget.TextView;
import android.widget.TimePicker;
import java.util.Calendar;
public class TimePickerActivity extends AppCompatActivity implements View.OnClickListener, TimePickerDialog.OnTimeSetListener {
    private TextView tv;
    private TimePicker tp;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_time_picker);
        findViewById(R.id.btn_ok).setOnClickListener(this);
        findViewById(R.id.btn_time).setOnClickListener(this);
        tv=findViewById(R.id.tv_date);
        tp = findViewById(R.id.timePicker);
    }
    @Override
    public void onClick(View view) {
        switch(view.getId()){
            case R.id.btn_ok:
                String desc=String.format("%d时%d分",tp.getCurrentHour(),tp.getCurrentMinute());
                tv.setText(desc);
                break;
            case R.id.btn_time:
                //获取日历实例，包含日期和时分
                Calendar instance = Calendar.getInstance();
                //构建时间对话框
//                TimePickerDialog tpd = new TimePickerDialog(this,this,
//                        instance.get(Calendar.HOUR_OF_DAY),
//                        instance.get(Calendar.MINUTE),
//                        true);
                //添加样式
                TimePickerDialog tpd = new TimePickerDialog(this, android.R.style.Theme_Holo_Dialog,this,
                        instance.get(Calendar.HOUR_OF_DAY),
                        instance.get(Calendar.MINUTE),
                        true);
                tpd.show();
                break;
        }
    }
    @Override
    public void onTimeSet(TimePicker timePicker, int i, int i1) {
        String desc=String.format("%d时%d分",i,i1);
        tv.setText(desc);
    }
}