关于Android 点击按钮弹出日期选择器

首先是 xml文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <Button
            android:id="@+id/BT"
            android:layout_width="100dp"
            android:layout_height="50dp"
            android:text="选择时间"/>

    </RelativeLayout>
</RelativeLayout>

然后是activity中的代码

package com.gxuwz.text;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.DatePickerDialog;
import android.app.Dialog;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.DatePicker;

import java.util.Calendar;

public class time extends AppCompatActivity {
    private Button bt;
    @SuppressLint("MissingSuperCall")

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.time);
        bt = findViewById(R.id.BT);
        bt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                showDatePickDlg();
            }
        });

    }
    public void showDatePickDlg () {
        Calendar calendar = Calendar.getInstance();
        DatePickerDialog datePickerDialog = new DatePickerDialog(time.this, new DatePickerDialog.OnDateSetListener() {

            @Override
            public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
                time.this.bt.setText(year + "-" + monthOfYear + "-" + dayOfMonth);
            }
        }, calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH));
        datePickerDialog.show();

    }

}