Table of contents
Copy the background image to the drawable directory
Open the string resource file strings.xml and enter the code
Open the main layout resource file activity_main.xml and enter the code:
theory:
In Android applications, the user is often required to choose from several options. Sometimes it is required to select only one, then a radio button (RadioButton) must be used, and sometimes the user is required to select multiple options, then a check box (CheckBox) must be used. .
radio button group
common attributes
| Attributes | meaning |
|---|---|
| orientation | vertical or horizontal, determines whether the radio buttons are arranged vertically or horizontally |
| layout_width | width (unit: dp) |
| layout_height | Height (unit: dp) |
Set up event listeners
| set listener | effect |
|---|---|
| setOnCheckedChangeListener | Listen for changes in the selected state of the radio button |
| setOnClickListener | Listen to whether the radio button group is clicked |
single button
common method
| method | effect |
|---|---|
| isChecked() | true or false, shows the checked state of the radio button |
| setChecked() | The parameter is true or false, used to set the selected state of the radio button |
Set up event listeners
| set listener | effect |
|---|---|
| setOnCheckedChangeListener | Listen for changes in the selected state of the radio button |
| setOnClickListener | Listen to whether the radio button is clicked |
check box
common method
| method | effect |
|---|---|
| isChecked() | true or false, shows the checked state of the checkbox |
| setChecked() | The parameter is true or false, which is used to set the selected state of the check box |
Set up event listeners
| set listener | effect |
|---|---|
| setOnCheckedChangeListener | Listen for changes in the checked state of the checkbox |
| setOnClickListener | Listen to whether the checkbox is clicked |
Inheritance diagram of three controls
Concrete example:
Create an Android application
Create an Android applicationSetBasicInformation
Copy the background image to drawablethe directory
Open the string resource file strings.xml and enter the code
Specific code:
<resources>
<string name="app_name">Set basic information</string>
<string name="set_information">Set basic information</string>
<string name="name">姓名：</string>
<string name="input_name">Please enter your name</string>
<string name="gender">性别：</string>
<string name="male">男</string>
<string name="female">女</string>
<string name="hobby">爱好：</string>
<string name="music">音乐</string>
<string name="read">阅读</string>
<string name="food">美食</string>
<string name="ok">确定</string>
<string name="clear">清除</string>
<string name="exit">退出</string>
</resources>
Open the main layout resource file activity_main.xmland enter the code:
<?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:background="@drawable/img"
android:orientation="vertical"
android:paddingLeft="20dp"
android:paddingRight="20dp"
android:paddingTop="50dp"
>
<TextView
android:id="@+id/tv_setinformation"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginBottom="30dp"
android:text="@string/set_information"
android:textColor="#0000ff"
android:textSize="30sp" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/name"
android:textColor="#000000"
android:textSize="20sp" />
<EditText
android:id="@+id/edt_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:hint="@string/input_name"
android:singleLine="true"
android:textSize="20sp"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_gender"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/gender"
android:textColor="#000000"
android:textSize="20sp" />
<RadioGroup
android:id="@+id/rg_gender"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<RadioButton
android:id="@+id/rb_male"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:checked="true"
android:text="@string/male"
android:textSize="20sp"/>
<RadioButton
android:id="@+id/rb_female"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="15dp"
android:text="@string/female"
android:textSize="20sp"/>
</RadioGroup>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_hobby"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hobby"
android:textColor="#000000"
android:textSize="20sp" />
<CheckBox
android:id="@+id/cb_music"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/music"
android:textSize="20sp"/>
<CheckBox
android:id="@+id/cb_read"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/read"
android:textSize="20sp"/>
<CheckBox
android:id="@+id/cb_food"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/food"
android:textSize="20sp"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="30dp">
<Button
android:id="@+id/btn_ok"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:onClick="doOK"
android:layout_marginRight="10dp"
android:text="@string/ok"
android:textSize="20sp"/>
<Button
android:id="@+id/btn_clear"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:onClick="doClear"
android:layout_marginRight="10dp"
android:text="@string/clear"
android:textSize="20sp"/>
<Button
android:id="@+id/btn_exit"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:onClick="doExit"
android:text="@string/exit"
android:textSize="20sp"/>
</LinearLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_marginTop="10dp"
android:background="#dddddd"/>
<TextView
android:id="@+id/tv_result"
android:layout_width="wrap_content"
android:layout_height="100dp"
android:layout_marginTop="30dp"
android:textSize="20sp"
/>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_marginTop="10dp"
android:background="#dddddd"/>
</LinearLayout>
Open the main interface classMainActivity输入代码：
Specific code:
package net.zyt.set_basic;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import java.util.Locale;
public class MainActivity extends AppCompatActivity {
private EditText etName;//Name edit box
private RadioGroup rgGender;//Gender radio button
private RadioButton rbMale;//Male radio button
private RadioButton rbFemale;//female radio button
private CheckBox cbMusic;//music check box
private CheckBox cbRead;//read the check box
private CheckBox cbFood;//food check box
private TextView tvResult;//end tag
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set up the user interface using the layout resource file
setContentView(R.layout.activity_main);
// Get the control instance through the resource identifier
etName=findViewById(R.id.edt_name);
rgGender=findViewById(R.id.rg_gender);
rbMale=findViewById(R.id.rb_male);
rbFemale=findViewById(R.id.rb_female);
cbMusic=findViewById(R.id.cb_music);
cbRead=findViewById(R.id.cb_read);
cbFood=findViewById(R.id.cb_food);
tvResult=findViewById(R.id.tv_result);
// //Register the click event handler method for the button
// rgGender.setOnClickListener(new View.OnClickListener() {
// @Override
// public void onClick(View v) {
// switch (rgGender.getCheckedRadioButtonId()) {
// case R.id.rb_male://Select male radio button
// Toast.makeText(MainActivity.this, "You chose 【Male】!", Toast.LENGTH_SHORT);
// break;
// case R.id.rb_female://Select female radio button
// Toast.makeText(MainActivity.this, "You chose 【Female】!", Toast.LENGTH_SHORT);
// break;
// }
// }
}
//Submit button click event handler method
public void doOK(View view) {
// get the name
String name = etName.getText().toString().trim();
// get gender
String gender = "";
//Determine which radio button is selected by the user
switch (rgGender.getCheckedRadioButtonId()) {// judge according to the selected radio button id
case R.id.rb_male://Select male radio button
gender = rbMale.getText().toString();
break;
case R.id.rb_female:
gender = rbFemale.getText().toString();
break;
}
// get hobbies
StringBuilder builder = new StringBuilder();//String Builder
//Determine whether the user has selected the music checkbox
if (cbMusic.isChecked()) {
builder.append(cbMusic.getText().toString() + "");
}
//Determine whether the user has selected the read checkbox
if (cbRead.isChecked()) {
builder.append(cbRead.getText().toString() + "");
}
//Determine whether the user has selected the gourmet checkbox
if (cbFood.isChecked()) {
builder.append(cbFood.getText().toString() + "");
}
String hobbies = builder.toString().trim();//remove spaces
//Display basic information through labels
String result = "姓名:" + name + "\n"
+ "gender" + "gender" + "\n"
+ "hobbies" + hobbies;
tvResult.setText(result);
}
// Clear button click event handler
public void doClear(View view) {
etName.setText("");
rbMale.setChecked(true);
cbMusic.setChecked(false);
cbRead.setChecked(false);
cbFood.setChecked(false);
tvResult.setText("");
}
// Exit button click event handler method
public void doExit(View view) {
finish();
}
}
The final running effect:
