作业5

package com.example.tn1;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

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

	public void click1(View view){
		Intent intent =new Intent(this,SecendActivity.class);
		startActivity(intent);
	}

}

　　

package com.example.tn1;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;

public class SecendActivity extends Activity {

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

	public void click2(View view){
		Intent intent=new Intent();
		intent.setAction("com.nn.activity2");
		startActivity(intent);
	}

}

　　

<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button 
        android:id="@+id/btu1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="界面1按钮"
       android:onClick="click1"
         />

</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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".SecendActivity" >

      <Button 
        android:id="@+id/btu2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="界面2按钮"
        android:onClick="click2"
         />
</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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".ThirdActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="界面3" />

</RelativeLayout>

 

2.

package com.example.charp2;

import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

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

     public void click1(View view){
            Intent intent=new Intent();
            intent.setAction("android.intent.action.VIEW");
            intent.setData(Uri.parse("http://www.baidu.com"));
            startActivity(intent);

}
     }

<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="打开浏览器"
        android:onClick="click1" />

</RelativeLayout>

　　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:orientation="vertical">

    <EditText
        android:id="@+id/edt1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="输入第一个数"
        android:textSize="25dp"
        />
    <EditText
        android:id="@+id/edt2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="输入第二个数"
        android:textSize="25dp"
        />

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        >
    <Button
        android:id="@+id/btn_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="+"
        android:textSize="25dp"
        android:onClick="click1"

        />
    <Button
        android:id="@+id/btn2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="-"
        android:textSize="25dp"
        android:onClick="click2"
        />
        <Button
            android:id="@+id/btn3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="*"
            android:textSize="25dp"
        android:onClick="click3"
            />
        <Button
        android:id="@+id/btn4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="/"
        android:textSize="25dp"
        android:onClick="click4"/>

   </LinearLayout>
    <TextView
        android:id="@+id/tv1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="结果是"
        android:textSize="25dp"
        />

</LinearLayout>

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

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.btn_1).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.edt1))).getText().toString();
                int n1=Integer.parseInt(num1);
                String num2=((EditText)(findViewById(R.id.edt2))).getText().toString();
                int n2=Integer.parseInt(num2);
                TextView tv1=(TextView) findViewById(R.id.tv1);
                int n3=n1+n2;
                tv1.setText("答案是"+n3);
            }
        });
        findViewById(R.id.btn2).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.edt1))).getText().toString();
                int n1=Integer.parseInt(num1);
                String num2=((EditText)(findViewById(R.id.edt2))).getText().toString();
                int n2=Integer.parseInt(num2);
                TextView tv1=(TextView) findViewById(R.id.tv1);
                int n3=n1-n2;
                tv1.setText(n3);
            }
        });
        findViewById(R.id.btn3).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.edt1))).getText().toString();
                int n1=Integer.parseInt(num1);
                String num2=((EditText)(findViewById(R.id.edt2))).getText().toString();
                int n2=Integer.parseInt(num2);
                TextView tv1=(TextView) findViewById(R.id.tv1);
                int n3=n1*n2;
                tv1.setText(n3);
            }
        });findViewById(R.id.btn4).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.edt1))).getText().toString();
                int n1=Integer.parseInt(num1);
                String num2=((EditText)(findViewById(R.id.edt2))).getText().toString();
                int n2=Integer.parseInt(num2);
                TextView tv1=(TextView) findViewById(R.id.tv1);
                int n3=n1/n2;
                tv1.setText(n3);
            }
        });
    }

}