Android基础控件
1、RadioGroup
单选框。
其中的按钮为控件:RadioButton。
实际效果图:
<?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="com.example.admin.vip_03.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="你喜欢谁?"
android:textSize="24dp"
/>
<RadioGroup
android:id="@+id/who"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="他"
/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="她"
/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="它"
/>
</RadioGroup>
</LinearLayout>
1.1 获取选中的按钮并Toast相应信息
private void initRadioGroup() {
RadioGroup radioGroup = findViewById(R.id.who);
//设置监听
radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
//通过checkedId找到被选中的按钮
RadioButton radioButton = findViewById(checkedId);
Toast toast = Toast.makeText(MainActivity.this, "我最喜欢:" + radioButton.getText(),
Toast.LENGTH_SHORT);
//改变Toast的位置
toast.setGravity(Gravity.TOP, 0, 0);
toast.show();
}
});
}
2、 CheckBox
复选框
<?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="com.example.admin.vip_03.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="你喜欢谁?"
android:textSize="24dp"
/>
<CheckBox
android:id="@+id/him"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="他"/>
<CheckBox
android:id="@+id/her"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="她"/>
<CheckBox
android:id="@+id/it"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="它"/>
</LinearLayout>
首先要在MainActivity中实现CompoundButton.OnCheckedChangeListener接口。
private void initCheckBox() {
CheckBox him = findViewById(R.id.him);
CheckBox her = findViewById(R.id.her);
CheckBox it = findViewById(R.id.it);
him.setOnCheckedChangeListener(this);
her.setOnCheckedChangeListener(this);
it.setOnCheckedChangeListener(this);
}
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(buttonView.isChecked()) {
Toast toast = Toast.makeText(MainActivity.this, buttonView.getText(),
Toast.LENGTH_SHORT);
toast.setGravity(Gravity.TOP, 0, 0);
toast.show();
}
else {
Toast toast = Toast.makeText(MainActivity.this, "我喜欢我自己",
Toast.LENGTH_SHORT);
toast.setGravity(Gravity.TOP, 0, 0);
toast.show();
}
}
2.1 改变图标
2.1.1 selector
首先将准备好的图片导入drawable目录中。同时在该目录下创建check_selector.xml文件。
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!--state_checked判断checkBox的状态-->
<item
android:state_checked="true"
android:drawable="@drawable/checked"
/>
<item
android:state_checked="false"
android:drawable="@drawable/unchecked"
/>
</selector>
最后在checkBox的属性加入选择器文件即可。
android:button="@drawable/check_selector"
2.1.2 style
找到res目录下的value文件夹下的style.xml文件。
加入以下代码。
<!-- style中的name为主题的名字
item中的name为修改的控件属性
-->
<style name="CheckBoxTheme" parent="Theme.AppCompat.Light.DarkActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
<item name="android:button">@drawable/check_selector</item>
</style>
最后在CheckBox中加入style属性。
style="@style/CheckBoxTheme"
实际效果:
图标找的太大,见谅。
3、 Spinner
3.1 xml文件写Spinner
首先在res/value目录下,新建arrays.xml文件。
文件内容:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string-array name="who">
<item>他</item>
<item>她</item>
<item>它</item>
</string-array>
</resources>
在Spinner控件的entries属性中,引用array.xml文件中的string-array。
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="你喜欢谁?"
android:textSize="30dp"
/>
<Spinner
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:entries="@array/who"
/>
Spinner的另一种显示方式:dialog
android:spinnerMode="dialog"
效果:
3.2 java文件写Spinner
3.2.1 ArrayAdapter
<Spinner
android:id="@+id/spinner"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</Spinner>
同时我们给Spinner加个监听器。
private void initSpinner() {
mSpinner = findViewById(R.id.spinner);
String[] string = {"他", "她", "它"} ;
//设置适配器
ArrayAdapter arrayAdapter = new ArrayAdapter(MainActivity.this, //上下文
android.R.layout.simple_list_item_1, //布局
string); //文件
mSpinner.setAdapter(arrayAdapter);
mSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast toast = Toast.makeText(MainActivity.this,
"我喜欢" + parent.getSelectedItem().toString(),
Toast.LENGTH_SHORT);
toast.setGravity(Gravity.TOP, 0, 0);
Toast toast1 = Toast.makeText(MainActivity.this,
"我喜欢" + string[position],
Toast.LENGTH_SHORT);
toast1.setGravity(Gravity.CENTER, 0, 0);
Toast toast2 = Toast.makeText(MainActivity.this,
"我喜欢" + arrayAdapter.getItem(position),
Toast.LENGTH_SHORT);
toast2.setGravity(Gravity.BOTTOM, 0, 0);
toast.show();
toast1.show();
toast2.show();
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
Toast.makeText(MainActivity.this,"Nothing", Toast.LENGTH_SHORT).show();
}
});
}
以上三种方式都能正确的吐司出选中的条目。
3.2.2 SimpleAdapter
本次我们用自己写的布局。
首先在layout文件夹下创建新的文件:list.xml。
<?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="horizontal"
android:gravity="center_horizontal"
>
<ImageView
android:id="@+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@mipmap/ic_launcher_round"
/>
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="条目"
android:layout_marginLeft="20dp"
android:textSize="20dp"
/>
</LinearLayout>
private void initSpinner() {
Spinner spinner = findViewById(R.id.spinner);
List<Map<String, Object>> listMap = new ArrayList<>();
for(int i = 0; i < 5; i++) {
Map<String, Object> map = new HashMap<>();
map.put("picture", R.mipmap.ic_launcher_round);
map.put("text", "条目" + i);
listMap.add(map);
}
//配置适配器
//String数组对应map中的String
//int数组对应list.xml中的控件id
//注意数组中,数据的顺序不能调换
SimpleAdapter simpleAdapter = new SimpleAdapter(MainActivity.this,
listMap,
R.layout.list,
new String[] {"picture", "text"},
new int[] {R.id.image, R.id.text}
);
spinner.setAdapter(simpleAdapter);
}
3.2.3 BaseAdapter
private void initSpinner() {
Spinner spinner = findViewById(R.id.spinner);
BaseAdapter baseAdapter = new BaseAdapter() {
@Override
//条目总数
public int getCount() {
return 7;
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView.inflate(MainActivity.this,
R.layout.list,
null);
return view;
}
};
spinner.setAdapter(baseAdapter);
}
4、常用写法
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.admin.vip_04.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="你喜欢谁?"
android:textSize="30dp"
/>
<Spinner
android:id="@+id/spinner"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
mn_list.xml
<?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="horizontal"
android:gravity="center_horizontal"
>
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="20dp"
/>
</LinearLayout>
MainActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Spinner;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initSpinner();
}
private void initSpinner() {
Spinner spinner = findViewById(R.id.spinner);
List<Meinv> list = new ArrayList<>();
for(int i = 0; i < 5; i++) {
Meinv meinv = new Meinv();
meinv.setId(i);
meinv.setTui(120);
meinv.setXiong("E");
list.add(meinv);
}
SpinnerAdapter adapter = new SpinnerAdapter(list, MainActivity.this);
spinner.setAdapter(adapter);
}
}
Meinv.java
package com.example.admin.vip_04;
public class Meinv {
private String xiong;
private int tui;
private int id;
public String getXiong() {
return xiong;
}
public void setXiong(String xiong) {
this.xiong = xiong;
}
public int getTui() {
return tui;
}
public void setTui(int tui) {
this.tui = tui;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Override
public String toString() {
return "Meinv{" +
"xiong='" + xiong + '\'' +
", tui=" + tui +
"cm, id=" + id +
'}';
}
}
SpinnerAdapter.java
package com.example.admin.vip_04;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
import java.util.List;
/**
* @author YiJiang
* @date 2018-03-17
*/
public class SpinnerAdapter extends BaseAdapter{
private List<Meinv> mMeinvList;
private Context mContext;
public SpinnerAdapter(List<Meinv> meinvList, Context context) {
mMeinvList = meinvList;
mContext = context;
}
@Override
public int getCount() {
return mMeinvList.size();
}
@Override
public Object getItem(int position) {
return mMeinvList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
convertView = View.inflate(mContext, R.layout.mn_list, null);
TextView textView = convertView.findViewById(R.id.text);
textView.setText(mMeinvList.get(position).toString());
return convertView;
}
}
实际效果: