第七周作业

<?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"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/bt_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#FFFFFF"
        android:text="打开界面2"
        android:textSize="20sp"
        android:textColor="#000000"
        android:layout_marginTop="20dp"
        android:layout_marginLeft="10dp"/>

</LinearLayout>

<?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"
    tools:context=".Main2Activity">

    <Button
        android:id="@+id/bt_2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#FFFFFF"
        android:text="打开界面3"
        android:textSize="20sp"
        android:textColor="#000000"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="20dp"/>

</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:background="#A5D4FA"
    tools:context=".Main3Activity">

    <TextView
        android:id="@+id/tv_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="这是界面3"
        android:textSize="40sp"
        android:layout_centerInParent="true"
        android:textColor="#000000"/>

</RelativeLayout>

package com.example.homework4;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button btn1=(Button)findViewById(R.id.bt_1);
        btn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent=new Intent(MainActivity.this,Main2Activity.class);
                startActivity(intent);
            }
        });
    }
}

package com.example.homework4;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class Main2Activity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        Button btn2=(Button)findViewById(R.id.bt_2);
        btn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent=new Intent();
                intent.setAction("com.ym.second");
                startActivity(intent);
            }
        });
    }
}

<?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">

    <Button
        android:id="@+id/bt_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开启访问百度"
        android:textSize="30dp"
        android:onClick="click1" />

</LinearLayout>

package com.example.myapplication103;
import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.util.Log;
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);
        Log.e("MainActivity", "调用oncreate");
    }

    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();
        Log.e("MainActivity", "调用onstart");
    }
    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        Log.e("MainActivity", "调用onresume");
    }
    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        Log.e("MainActivity", "调用onpause");
    }

    @Override
    protected void onStop() {
        // TODO Auto-generated method stub
        super.onStop();
        Log.e("MainActivity", "调用onstop");
    }

    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        Log.e("MainActivity", "调用ondestroy");
    }

    @Override
    protected void onRestart() {
        // TODO Auto-generated method stub
        super.onRestart();
        Log.e("MainActivity", "调用onRestart");
    }

    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);

    }

}

 

 

<?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"
    tools:context=".Main2Activity"
    android:layout_margin="20dp">
    <TextView
        android:id="@+id/tv1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="数字:"
        android:textColor="#000000"
        android:textSize="20sp"
        android:layout_marginTop="15dp"/>
    <EditText
        android:id="@+id/et1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入数字"
        android:textSize="25sp"
        android:textColorHint="#E91313"
        android:maxLines="1"
        android:scrollHorizontally="true"
        android:layout_toRightOf="@+id/tv1"/>
    <TextView
        android:id="@+id/tv2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="数字:"
        android:textColor="#000000"
        android:textSize="20sp"
        android:layout_marginTop="25dp"
        android:layout_below="@id/tv1"/>
    <EditText
        android:id="@+id/et2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入数字"
        android:textSize="25sp"
        android:textColorHint="#E91313"
        android:maxLines="1"
        android:scrollHorizontally="true"
        android:layout_toRightOf="@+id/tv1"
        android:layout_below="@id/et1"/>
    <Button
        android:id="@+id/btn_1"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:text="+"
        android:textColor="#000000"
        android:textSize="50sp"
        android:layout_below="@id/et2"
        android:layout_marginTop="100dp"
        android:layout_margin="10dp"
        android:layout_alignLeft="@id/et2" />
    <Button
        android:id="@+id/btn_2"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:text="-"
        android:textColor="#000000"
        android:textSize="50sp"
        android:layout_below="@id/et2"
        android:layout_toRightOf="@id/btn_1" />
    <Button
        android:id="@+id/btn_3"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_below="@id/btn_1"
        android:layout_margin="10dp"
        android:text="*"
        android:textColor="#000000"
        android:textSize="50sp"
        android:layout_alignLeft="@id/et2" />
    <Button
        android:id="@+id/btn_4"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_below="@id/btn_1"
        android:layout_toRightOf="@id/btn_3"
        android:text="/"
        android:textColor="#000000"
        android:textSize="50sp"
        android:layout_alignTop="@id/btn_3" />
    <TextView
        android:id="@+id/tv3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/btn_3"
        android:layout_margin="20dp"
        android:text="结果是："
        android:textSize="45sp"
        android:textColor="#000000"
        android:textStyle="italic"/>
</RelativeLayout>

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 Main2Activity extends AppCompatActivity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        //+
        findViewById(R.id.btn_1).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int n3=n1+n2;
                TextView tv1=(TextView)findViewById(R.id.tv3);
                tv1.setText("结果是"+n3);
            }
        });
        //-
        findViewById(R.id.btn_2).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int n3=n1-n2;
                TextView tv1=(TextView)findViewById(R.id.tv3);
                tv1.setText("结果是"+n3);
            }
        });
        //*
        findViewById(R.id.btn_3).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int n3=n1*n2;
                TextView tv1=(TextView)findViewById(R.id.tv3);
                tv1.setText("结果是"+n3);
            }
        });
        //除
        findViewById(R.id.btn_4).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById(R.id.et1))).getText().toString();
                String num2=((EditText)(findViewById(R.id.et2))).getText().toString();
                int n1=Integer.parseInt(num1);
                int n2=Integer.parseInt(num2);
                int n3=n1/n2;
                TextView tv1=(TextView)findViewById(R.id.tv3);
                tv1.setText("结果是"+n3);
            }
        });
    }
}