Android学习笔记3-2

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3-2 AlertDialog

activity_dialog.xml文件

  <?xml version="1.0" encoding="utf-8"?>
  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:orientation="vertical">
  
      <Button
          android:id="@+id/btn_dialog1"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="style1"
          android:textAllCaps="false"/>
      <Button
          android:id="@+id/btn_dialog2"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="style2"
          android:textAllCaps="false"/>
      <Button
          android:id="@+id/btn_dialog3"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="style3"
          android:textAllCaps="false"/>
      <Button
          android:id="@+id/btn_dialog4"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="style4"
          android:textAllCaps="false"/>
      <Button
          android:id="@+id/btn_dialog5"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="style5"
          android:textAllCaps="false"/>
  </LinearLayout>

效果

layout_dialog.xml文件,自定义布局

  <?xml version="1.0" encoding="utf-8"?>
  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="vertical"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:padding="15dp">
      <EditText
          android:id="@+id/et_username"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:hint="username"
          android:maxLines="1"/>
      <EditText
          android:id="@+id/et_password"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:hint="password"
          android:inputType="textPassword"
          android:maxLines="1"
          android:layout_marginTop="10dp"/>
      <Button
          android:id="@+id/btn_login"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="login"
          android:textAllCaps="false"
          android:layout_marginTop="10dp"/>
  </LinearLayout>

效果

DialogActivity.java文件

  package com.ylw.helloworld;
  
  import androidx.appcompat.app.AlertDialog;
  import androidx.appcompat.app.AppCompatActivity;
  
  import android.content.DialogInterface;
  import android.content.Intent;
  import android.os.Bundle;
  import android.text.Layout;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.widget.Button;
  import android.widget.EditText;
  
  import com.ylw.helloworld.util.ToastUtil;
  
  public class DialogActivity extends AppCompatActivity {
  
      private Button mBtnDialog1,mBtnDialog2,mBtnDialog3,mBtnDialog4,mBtnDialog5;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_dialog);
  
          mBtnDialog1 = findViewById(R.id.btn_dialog1);
          mBtnDialog2 = findViewById(R.id.btn_dialog2);
          mBtnDialog3 = findViewById(R.id.btn_dialog3);
          mBtnDialog4 = findViewById(R.id.btn_dialog4);
          mBtnDialog5 = findViewById(R.id.btn_dialog5);
  
          OnClick onClick = new OnClick();
          mBtnDialog1.setOnClickListener(onClick);
          mBtnDialog2.setOnClickListener(onClick);
          mBtnDialog3.setOnClickListener(onClick);
          mBtnDialog4.setOnClickListener(onClick);
          mBtnDialog5.setOnClickListener(onClick);
      }
  
      class OnClick implements View.OnClickListener{
          @Override
          public void onClick(View v) {
              switch (v.getId()){
                  case R.id.btn_dialog1:  //默认样式
                      AlertDialog.Builder builder = new AlertDialog.Builder(DialogActivity.this);
                      //builder.setTitle("请回答");
                      //builder.setMessage("你想学习Android吗？");
                      //还可以用链式，因为返回值也是builder
                      builder.setTitle("请回答").setMessage("你想学习Android吗？")
                              .setIcon(R.drawable.icon_user)
                              .setPositiveButton("想", new DialogInterface.OnClickListener() {
                                  @Override
                                  public void onClick(DialogInterface dialog, int which) {
                                      ToastUtil.showMsg(DialogActivity.this,"不，你不想");
                                  }
                              }).setNeutralButton("还行", new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              ToastUtil.showMsg(DialogActivity.this,"你再想想");
                          }
                      }).setNegativeButton("不想", new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              ToastUtil.showMsg(DialogActivity.this,"你很诚实");
                          }
                      }).show();
                      break;
                  case R.id.btn_dialog2:  //单选样式1
                      final String [] array2 = new String[]{"男","女"};
                      AlertDialog.Builder builder2 = new AlertDialog.Builder(DialogActivity.this);
                      builder2.setTitle("选择性别").setItems(array2, new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              ToastUtil.showMsg(DialogActivity.this,array2[which]);
                          }
                      }).show();
                      break;
                  case R.id.btn_dialog3:  //单选样式2
                      final String [] array3 = new String[]{"男","女"};
                      AlertDialog.Builder builder3 = new AlertDialog.Builder(DialogActivity.this);
                      //setSingleChoiceItems(数组，默认选中的数组索引，监听)
                      builder3.setTitle("选择性别").setSingleChoiceItems(array3, 0, new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              ToastUtil.showMsg(DialogActivity.this,array3[which]);
                              dialog.dismiss();   //点击选项时对话框消失
                          }
                      }).setCancelable(false).show(); //setCancelable(false)点击其他部分不会关闭对话框,配合dialog.dismiss()使用
                      break;
                  case R.id.btn_dialog4:  //多选
                      final String[] array4 = new String[]{"唱歌","跳舞","写代码"};
                      boolean[] isSelected = new boolean[]{false,false,true};
                      AlertDialog.Builder builder4 = new AlertDialog.Builder(DialogActivity.this);
                      builder4.setTitle("选择兴趣").setMultiChoiceItems(array4, isSelected, new DialogInterface.OnMultiChoiceClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which, boolean isChecked) {
                              ToastUtil.showMsg(DialogActivity.this,array4[which]+":"+isChecked);
                          }
                      }).setPositiveButton("确定", new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              //
                          }
                      }).setNegativeButton("取消", new DialogInterface.OnClickListener() {
                          @Override
                          public void onClick(DialogInterface dialog, int which) {
                              //
                          }
                      }).show();
                      break;
                  case R.id.btn_dialog5:     //自定义布局
                      AlertDialog.Builder builder5 = new AlertDialog.Builder(DialogActivity.this);
                      View view =  LayoutInflater.from(DialogActivity.this).inflate(R.layout.layout_dialog,null);
                      EditText etUserName = view.findViewById(R.id.et_username);
                      EditText etPassWord = view.findViewById(R.id.et_password);
                      Button btnLogin = view.findViewById(R.id.btn_login);
                      btnLogin.setOnClickListener(new View.OnClickListener() {
                          @Override
                          public void onClick(View v) {
                              //
                          }
                      });
                      builder5.setTitle("请先登录").setView(view).show();
                      break;
              }
          }
      }
  }