第四次作业

1.

 

package com.example.areturn;

import android.os.Bundle;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    // 当点击返回按钮时
    public void onBackPressed() {
        AlertDialog dialog;
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setIcon(R.drawable.mao);
        builder.setTitle("普通对话框");
        builder.setMessage("是否退出应用程序？");
        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
                MainActivity.this.finish();// 主窗口关闭

            }
        });
        builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();

            }
        });

        dialog = builder.create();
        dialog.show();

    }

}

 

 

 

2.

 

<?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"
    android:padding="15dp">

    <RadioGroup
        android:id="@+id/rg_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical">
        <RadioButton
            android:id="@+id/rb_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="男"
            android:checked="true"
            android:textSize="18sp"
            android:textColor="#FF6600"
            android:onClick="click1"/>
        <RadioButton
            android:id="@+id/rb_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="女"
            android:textSize="18sp"
            android:textColor="#FF6600"
            android:onClick="click2"/>
    </RadioGroup>



</RelativeLayout>

package com.example.a03;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    } public void click1(View view){
        Toast.makeText(this,"您选择的是男",Toast.LENGTH_LONG).show();
    }
    public void click2(View view){
        Toast.makeText(this,"您选择的是女",Toast.LENGTH_LONG).show();
    }
}

　　

 3.

<?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"
    tools:context=".MainActivity"
    android:background="#85FF01"
    android:orientation="vertical">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="60dp"
        android:text="1.TextView显示的文本信息"
        android:textSize="25dp"
        android:layout_marginLeft="50dp"
        android:textColor="#FF0000"
        />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="61dp"
        android:layout_marginRight="50dp"
        android:textSize="25dp"
        android:text="2.按钮"
        android:textColor="#FF0000" />
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="3.编辑框:请输入信息"
        android:textSize="25dp"
        android:textColor="#FF0000"
        android:layout_marginLeft="25dp"
        android:layout_marginTop="62dp"/>
    <RadioGroup
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="15dp"
        android:orientation="horizontal">
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="4.男"
            android:checked="true"
            android:textColor="#FF0000"
            android:textSize="25dp"></RadioButton>
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="女"
            android:textColor="#FF0000"
            android:textSize="25dp"></RadioButton>

    </RadioGroup>
    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="电脑"
        android:textSize="25dp"
        android:textColor="#FF0000"
        android:checked="true"
        android:layout_marginLeft="20dp"
        />
    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="手机"
        android:textSize="25dp"
        android:textColor="#FF0000"
        android:checked="true"
        android:layout_marginLeft="20dp"
        />

</LinearLayout>

 

 4.

<?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"
    tools:context=".MainActivity"
    android:orientation="vertical">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="45dp"
        android:text="购物商城"
        android:background="#FF8F03"
        android:textSize="18sp"
        android:textColor="#FFFFFF"
        android:gravity="center"/>
    <ListView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/Iv"
        />
</LinearLayout>

<?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:padding="16dp">
<ImageView
    android:layout_width="120dp"
    android:layout_height="90dp"
    android:id="@+id/iv"
    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:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/title"
        android:text="桌子"
        android:textSize="20sp"
        android:textColor="#000000"
        />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tv_price"
        android:text="价格"
        android:layout_below="@id/title"
        android:layout_marginTop="10dp"
        android:textSize="20sp"
        android:textColor="#FF8F03"
        />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/price"
        android:text="1000"
        android:textSize="20sp"
        android:layout_below="@id/title"
        android:layout_toRightOf="@id/tv_price"
        android:layout_marginTop="10dp"
        android:textColor="#FF8F03"
        />
</RelativeLayout>


</RelativeLayout>

package com.example.zy4;

import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.ViewUtils;

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 MainActivity 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.zhuoz,R.drawable.pguo,R.drawable.cake,R.drawable.xianyi,R.drawable.mht,R.drawable.wj};
protected  void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mListView =(ListView) findViewById(R.id.Iv);
    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;
    }


    class ViewHolder{
        TextView title,price;
        ImageView iv;
    }
    public View getView(int position, View convertView,ViewGroup parent){
        ViewHolder holder=null;
        if (convertView==null){
            convertView =View.inflate(MainActivity.this,R.layout.activity_item,null);
            holder=new ViewHolder();
            holder=new ViewHolder();
            holder.title=(TextView) convertView.findViewById(R.id.title);
            holder.price=(TextView) convertView.findViewById(R.id.price);
            holder.iv=(ImageView) convertView.findViewById(R.id.iv) ;
        convertView.setTag(holder);
        }else {
            holder=(ViewHolder) convertView.getTag();

        }
        holder.title.setText(titles[position]);
        holder.price.setText(prices[position]);
        holder.iv.setBackgroundResource(icons[position]);
        return  convertView;
    }
}


}