第三次作业

1
package com.example.test;
 
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
 
import android.content.DialogInterface;
import android.os.Bundle;
 
public class MainActivity extends AppCompatActivity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    public void onBackPressed(){
        final AlertDialog dialog;
        AlertDialog.Builder builder=new AlertDialog.Builder(this)
                .setTitle("普通对话框")
                .setIcon(R.mipmap.ic_launcher)
                .setMessage("是否确定退出应用：")
                .setPositiveButton("是", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                        MainActivity.this.finish();
 
                    }
                })
                .setNegativeButton("否", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
 
                    }
                });
        dialog=builder.create();
        dialog.show();
 
    }
}

 

 

 2

package com.example.myapplication;
 
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
 
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
 
public class Demo4Activity extends AppCompatActivity implements View.OnClickListener {
 
    private String[] sexArry={"男","女"};
    private int sex=0;
    private TextView textView;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_demo4);
 
        findViewById(R.id.bt).setOnClickListener(this);
    }
 
 
    @Override
    public void onClick(View view) {
        AlertDialog dialog;
        AlertDialog.Builder builder=new AlertDialog.Builder(this)
            .setTitle("选择你的性别")
            .setSingleChoiceItems(new String[]{"男", "女"},sex, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int i) {
                    sex=i;
                }
            })
                .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int i) {
                        dialog.dismiss();
                        if (sex==0){
                            Toast.makeText(Demo4Activity.this, "你选择的性别是男", Toast.LENGTH_SHORT).show();
                        }else{
                            Toast.makeText(Demo4Activity.this, "你选择的性别是女", Toast.LENGTH_SHORT).show();
                        }
 
                    }
                })
                .setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int i) {
                        dialog.dismiss();
                    }
                });
 
        dialog=builder.create();
        dialog.show();
 
    }

 

 

 

 

 

 

 3

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    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:background="#31B404"
    android:layout_margin="2dp"
    tools:context=".MyLayout">
    <TextView
        android:id="@+id/tv_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="1.TextView显示文本信息"
        android:textSize="20sp"
        android:textColor="#FF0000"
        android:textStyle="bold"
        android:gravity="center"
        android:layout_marginTop="10dp"
        />
    <Button
        android:id="@+id/btn_1"
        android:layout_width="350dp"
        android:layout_height="wrap_content"
        android:text="2.按钮"
        android:textSize="20sp"
        android:textColor="#FF0000"
        android:textStyle="bold"
        android:padding="5dp"
        android:layout_centerHorizontal="true"
        android:layout_below="@+id/tv_1"
        />
    <EditText
        android:id="@+id/et_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="3.编辑框：请输入信息"
        android:textSize="20sp"
        android:textColorHint="#FF0000"
        android:layout_below="@id/btn_1"
        android:layout_alignStart="@id/btn_1"
        android:layout_margin="5dp"
        />
    <RadioGroup
        android:id="@+id/rg_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_below="@id/et_1"
        android:layout_alignLeft="@id/et_1"
        >
        <RadioButton
            android:id="@+id/rb_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="4.男"
            android:textColor="#FF0000"
            android:textSize="20sp"
            android:textStyle="bold"
            />
        <RadioButton
            android:id="@+id/rb_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="女"
            android:textColor="#FF0000"
            android:textSize="20sp"
            android:textStyle="bold"
            />
        </RadioGroup>
    <LinearLayout
        android:id="@+id/ll_1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:layout_below="@id/rg_1"
        android:layout_alignLeft="@id/rg_1">
        <CheckBox
            android:id="@+id/cb_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="电脑"
            android:textSize="20sp"
            />
        <CheckBox
            android:id="@+id/cb_2"
            android:layout

 

_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="手机"
            android:textSize="20sp"/>
    </LinearLayout>
</RelativeLayout>

 

 

 

 

 

 

4.

 

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

public class Demo6Activity extends AppCompatActivity {

    private ListView mListView;
    private String[] titles={"桌子","苹果","蛋糕","线衣","猕猴桃","围巾"};
    private String[] prices={"1800元","10元/kg","300元","350元","10元/kg","280元"};
    private int[] icons={R.drawable.table,R.drawable.apple,R.drawable.cake,R.drawable.wireclothes,R.drawable.kiwifruit,R.drawable.scarf};
    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_demo6);
        mListView=(ListView) findViewById(R.id.lv);
        MyBaseAdapter mAdapter=new MyBaseAdapter();
        mListView.setAdapter(mAdapter);

    }
    class MyBaseAdapter extends BaseAdapter{
        public int getCount(){
            return titles.length;
        }
        public Object getItem(int position){
            return titles[position];

        }
        public long getItemId(int position){
            return position;
        }
        public View getView(int position, View convertView, ViewGroup parent){
            View view=View.inflate(Demo6Activity.this,R.layout.list_item,null);
            TextView title=view.findViewById(R.id.title);
            TextView price=view.findViewById(R.id.price);
            ImageView iv=view.findViewById(R.id.iv);
            title.setText(titles[position]);
            price.setText(prices[position]);
            iv.setBackgroundResource(icons[position]);
            return view;
        }
    }
}
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="16dp">
    <ImageView
        android:id="@+id/iv"
        android:layout_width="120dp"
        android:layout_height="90dp"
        android:layout_centerVertical="true"/>
    <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_toRightOf="@id/iv"
        android:layout_centerVertical="true">
        <TextView
            android:id="@+id/title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="桌子"
            android:textSize="20sp"
            android:textColor="#000000"/>
        <TextView
            android:id="@+id/tv_price"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="价格"
            android:textSize="20sp"
            android:textColor="#FF8F03"
            android:layout_marginTop="10dp"
            android:layout_below="@id/title"/>
        <TextView
            android:id="@+id/price"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="1000"
            android:textSize="20sp"
            android:textColor="#38EE74"
            android:layout_below="@id/title"
            android:layout_toRightOf="@id/tv_price"
            android:layout_marginTop="10dp"/>
    </RelativeLayout>

</RelativeLayout>
<?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"
    tools:context=".Demo6Activity"
    android:orientation="vertical">
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="45dp"
        android:text="购物商城"
        android:textSize="18sp"
        android:textColor="#FFFFFF"
        android:background="#FF8F03"
        android:gravity="center"/>
    <ListView
        android:id="@+id/lv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

</LinearLayout>