56周作业

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mb5ffd6f53cf9c6 2021-09-25 13:52:00

文章标签 android xml ide bundle ico 文章分类 Android 移动开发

1.返回键实现对话框弹出是否退出应用程序

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.app.AlertDialog;
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);
    }

    @Override
    public void onBackPressed() {
        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("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                        MainActivity.this.finish();

                    }
                })
                .setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
                });
        dialog=builder.create();
        dialog.show();
    }
}

56周作业_android

2.实现以下场景：从一个activity中点击一个按钮后，弹出一个单选按钮对话框，上面有“男”“女”两个选项，选定后，TOAST弹出你选择了男，或你选择了女

<?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="#BF0060"
            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="#BF0060"
            android:onClick="click2"/>
    </RadioGroup>



</RelativeLayout>

package com.example.myapplication;

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();
    }
}

56周作业_xml_02

3.布局(详见:Android第五周上机word文档)

<?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">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="1.TextView显示的文本信息"
        android:textSize="25dp"
        android:layout_marginLeft="50dp"
        android:textColor="#8E8E8E"
        />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="10dp"
        android:layout_marginRight="50dp"
        android:textSize="25dp"
        android:text="2.按钮"
        android:textColor="#8E8E8E    " />
    <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="#8E8E8E    "
        android:layout_marginLeft="25dp"
        android:layout_marginTop="10dp"/>
    <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="#8E8E8E"
            android:textSize="25dp"></RadioButton>
        <RadioButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="女"
            android:textColor="#8E8E8E    "
            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="#8E8E8E    "
        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="#8E8E8E    "
        android:checked="true"
        android:layout_marginLeft="20dp"
        />

</LinearLayout>

56周作业_xml_03

4.教材p76页图3—17购物商城界面

<?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="#53FF53"
        android:textSize="18sp"
        android:textColor="#FFFF37"
        android:gravity="center"/>
    <ListView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/lv" />
</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="#FFFF37"
            />
        <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="#FFFF37"
            />
        <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="#FFFF37"
            />
    </RelativeLayout>


</RelativeLayout>

package com.example.myapplication;
import androidx.appcompat.widget.ViewUtils;
import android.app.Activity;
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 Activity {
    private ListView mListView;
    //商品名称与价格数据集合
    private String[ ] titles = {"桌子","苹果","蛋糕","线衣","猕猴桃","围巾"};
    private String[ ] prices = {"1000元","10元/kg","300元","350元","10元/kg","280元"};
    //图片数据集合
    private int[ ] icons = {R.drawable.table,R.drawable.apple,R.drawable.cake,R.drawable.
            wireclothes,R.drawable.kiwifruit,R.drawable.scarf};

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mListView = (ListView)findViewById(R.id.lv); //初始化ListView 控件
        MyBaseAdapter mAdapter = new MyBaseAdapter();//创建一个Adapter实例
        mListView.setAdapter(mAdapter);              //设置Adapter
    }
    class MyBaseAdapter extends BaseAdapter{
        @Override
        public int getCount(){                       //获取item的总数
            return titles.length;                    //返回ListView Item条目的总数
        }
        @Override
        public Object getItem(int position){
            return titles[position];                 //返回Item的数据对象
        }
        @Override
        public long getItemId(int position){
            return position;                         //返回Item的id
        }
        //得到Item的View视图
        @Override
        public View getView(int position,View convertView,ViewGroup parent){
            //加载list_item.xml布局文件
            View view = View.inflate(MainActivity.this,R.layout.list_item,null);
            TextView title = (TextView) view.findViewById(R.id.title);
            TextView price = (TextView) view.findViewById(R.id.price);
            ImageView iv = (ImageView) view.findViewById(R.id.iv);
            title.setText(titles[position]);
            price.setText(prices[position]);
            iv.setBackgroundResource(icons[position]);
            return view;
        }
    }
}package com.example.myapplication;
import androidx.appcompat.widget.ViewUtils;
import android.app.Activity;
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 Activity {
    private ListView mListView;
    //商品名称与价格数据集合
    private String[ ] titles = {"桌子","苹果","蛋糕","线衣","猕猴桃","围巾"};
    private String[ ] prices = {"1000元","10元/kg","300元","350元","10元/kg","280元"};
    //图片数据集合
    private int[ ] icons = {R.drawable.table,R.drawable.apple,R.drawable.cake,R.drawable.
            wireclothes,R.drawable.kiwifruit,R.drawable.scarf};

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mListView = (ListView)findViewById(R.id.lv); //初始化ListView 控件
        MyBaseAdapter mAdapter = new MyBaseAdapter();//创建一个Adapter实例
        mListView.setAdapter(mAdapter);              //设置Adapter
    }
    class MyBaseAdapter extends BaseAdapter{
        @Override
        public int getCount(){                       //获取item的总数
            return titles.length;                    //返回ListView Item条目的总数
        }
        @Override
        public Object getItem(int position){
            return titles[position];                 //返回Item的数据对象
        }
        @Override
        public long getItemId(int position){
            return position;                         //返回Item的id
        }
        //得到Item的View视图
        @Override
        public View getView(int position,View convertView,ViewGroup parent){
            //加载list_item.xml布局文件
            View view = View.inflate(MainActivity.this,R.layout.list_item,null);
            TextView title = (TextView) view.findViewById(R.id.title);
            TextView price = (TextView) view.findViewById(R.id.price);
            ImageView iv = (ImageView) view.findViewById(R.id.iv);
            title.setText(titles[position]);
            price.setText(prices[position]);
            iv.setBackgroundResource(icons[position]);
            return view;
        }
    }
}