AS第七周作业

1.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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=".MainActivity"
    >
<Button
    android:id="@+id/bt1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="启动界面二"
    />

<Button
    android:id="@+id/bt2"
    android:onClick="click2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="打开百度"
    android:layout_below="@id/bt1"
    />
</RelativeLayout>

<RelativeLayout 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=".SecondActivity">
    <Button
        android:id="@+id/bt2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="启动界面三"
        />

</RelativeLayout>

<RelativeLayout 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=".ThirdActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello world!" />

</RelativeLayout>

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Intent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class SecondActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
        Button bt2=(Button)findViewById(R.id.bt2);
        bt2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent=new Intent();
                intent.setAction("com.lrp.start");
                intent.addCategory("android.intent.category.DEFAULT");
                startActivity(intent);
            }
        });
    }
}

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;

public class ThirdActivity extends AppCompatActivity {

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

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.content.Intent;
import android.view.View.OnClickListener;
import android.net.Uri;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button bt1=(Button)findViewById(R.id.bt1);
        Button bt2=(Button)findViewById(R.id.bt2);

        bt1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent=new Intent(MainActivity.this,SecondActivity.class);
                startActivity(intent);
            }
        });


    }
    public void click2(View view){
        Intent intent=new Intent();
        intent.setAction("android.intent.action.VIEW");
        intent.setData(Uri.parse("http://www.baidu.com"));
        startActivity(intent);
    }
}

 

 

 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"
    android:orientation="vertical"
    android:id="@+id/a_1"
    android:background="#cceeff"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/tv_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="20dp"
        android:text="计算器"
        android:textSize="25dp" />

    <EditText
        android:id="@+id/et_1"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:hint="请输入一个数"
        android:layout_marginLeft="100dp"
        android:layout_marginRight="100dp"
        android:layout_marginTop="100dp"
        android:inputType="number"
        android:gravity="center"
        android:textSize="20sp"/>
    <EditText
        android:id="@+id/et_2"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:hint="请输入一个数"
        android:layout_marginLeft="100dp"
        android:layout_marginRight="100dp"
        android:inputType="number"
        android:gravity="center"
        android:textSize="20sp" />
    <LinearLayout
        android:id="@+id/a_2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_marginTop="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginLeft="20dp">
        <Button
            android:id="@+id/bt_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="加(+)"
            android:background="#ff0000"/>
        <Button
            android:id="@+id/bt_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="减(-)"
            android:background="#ffcc22" />
        <Button
            android:id="@+id/bt_3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="乘(*)"
            android:background="#0066ff"/>
        <Button
            android:id="@+id/bt_4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="除(/)"
            android:background="#00ff00"/>
    </LinearLayout>
    <TextView
        android:id="@+id/tv_2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="结果="
        android:textSize="25sp"
        android:textColor="#000000"
        android:layout_marginLeft="150dp"
        android:layout_marginRight="150dp"
        android:layout_marginTop="50dp"
        android:gravity="center"/>


</LinearLayout>

package com.example.myapplication;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.bt_1).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et_1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et_2))).getText().toString();

                int n1= Integer.parseInt(num1);
                int n2= Integer.parseInt(num2);
                int sum=n1+n2;
                TextView tv_1=findViewById(R.id.tv_2);//获取TextView 控件
                tv_1.setText("结果="+sum);
            }
        });
        findViewById(R.id.bt_2).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et_1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et_2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int sum=n1-n2;
                TextView tv_1=findViewById(R.id.tv_2);
                tv_1.setText("结果="+sum);
            }
        });
        findViewById(R.id.bt_3).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et_1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et_2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int sum=n1*n2;
                TextView tv_1=findViewById(R.id.tv_2);
                tv_1.setText("结果="+sum);
            }
        });
        findViewById(R.id.bt_4).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et_1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et_2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int sum=n1/n2;
                TextView tv_1=findViewById(R.id.tv_2);
                tv_1.setText("结果="+sum);
            }
        });
    }
}