第七周作业
1.三个界面,界面1点击按钮使用显式意图开启界面2.界面2点击按钮隐式意图开启界面3
2.在界面1做一个按钮开启浏览器访问百度
1 <?xml version="1.0" encoding="utf-8"?> 2 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 3 xmlns:tools="http://schemas.android.com/tools" 4 android:layout_width="match_parent" 5 android:layout_height="match_parent" 6 tools:context=".MainActivity" 7 > 8 <Button 9 android:id="@+id/bt1" 10 android:layout_width="wrap_content" 11 android:layout_height="wrap_content" 12 android:text="启动界面二" 13 /> 14 15 <Button 16 android:id="@+id/bt2" 17 android:onClick="click2" 18 android:layout_width="wrap_content" 19 android:layout_height="wrap_content" 20 android:text="打开百度" 21 android:layout_below="@id/bt1" 22 /> 23 </RelativeLayout>
1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 xmlns:tools="http://schemas.android.com/tools" 3 android:layout_width="match_parent" 4 android:layout_height="match_parent" 5 tools:context=".SecondActivity"> 6 <Button 7 android:id="@+id/bt2" 8 android:layout_width="wrap_content" 9 android:layout_height="wrap_content" 10 android:text="启动界面三" 11 /> 12 13 </RelativeLayout>
1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 xmlns:tools="http://schemas.android.com/tools" 3 android:layout_width="match_parent" 4 android:layout_height="match_parent" 5 tools:context=".ThirdActivity" > 6 7 <TextView 8 android:layout_width="wrap_content" 9 android:layout_height="wrap_content" 10 android:text="Hello world!" /> 11 12 </RelativeLayout>
1 package com.example.myapplication; 2 3 import androidx.appcompat.app.AppCompatActivity; 4 import android.os.Bundle; 5 import android.view.View; 6 import android.widget.Button; 7 import android.content.Intent; 8 import android.view.View.OnClickListener; 9 import android.net.Uri; 10 11 public class MainActivity extends AppCompatActivity { 12 13 @Override 14 protected void onCreate(Bundle savedInstanceState) { 15 super.onCreate(savedInstanceState); 16 setContentView(R.layout.activity_main); 17 Button bt1=(Button)findViewById(R.id.bt1); 18 Button bt2=(Button)findViewById(R.id.bt2); 19 20 bt1.setOnClickListener(new OnClickListener() { 21 22 @Override 23 public void onClick(View v) { 24 // TODO Auto-generated method stub 25 Intent intent=new Intent(MainActivity.this,SecondActivity.class); 26 startActivity(intent); 27 } 28 }); 29 30 31 } 32 public void click2(View view){ 33 Intent intent=new Intent(); 34 intent.setAction("android.intent.action.VIEW"); 35 intent.setData(Uri.parse("http://www.baidu.com")); 36 startActivity(intent); 37 } 38 }
1 package com.example.myapplication; 2 3 import androidx.appcompat.app.AppCompatActivity; 4 import android.os.Bundle; 5 import android.content.Intent; 6 import android.view.View; 7 import android.view.View.OnClickListener; 8 import android.widget.Button; 9 10 public class SecondActivity extends AppCompatActivity { 11 12 @Override 13 protected void onCreate(Bundle savedInstanceState) { 14 super.onCreate(savedInstanceState); 15 setContentView(R.layout.activity_second); 16 Button bt2=(Button)findViewById(R.id.bt2); 17 bt2.setOnClickListener(new OnClickListener() { 18 19 @Override 20 public void onClick(View v) { 21 // TODO Auto-generated method stub 22 Intent intent=new Intent(); 23 intent.setAction("com.lrp.start"); 24 intent.addCategory("android.intent.category.DEFAULT"); 25 startActivity(intent); 26 } 27 }); 28 } 29 }
1 package com.example.myapplication; 2 3 import androidx.appcompat.app.AppCompatActivity; 4 import android.os.Bundle; 5 6 public class ThirdActivity extends AppCompatActivity { 7 8 @Override 9 protected void onCreate(Bundle savedInstanceState) { 10 super.onCreate(savedInstanceState); 11 setContentView(R.layout.activity_third); 12 } 13 }
2.在界面1做一个按钮开启浏览器访问百度
1 <?xml version="1.0" encoding="utf-8"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3 xmlns:app="http://schemas.android.com/apk/res-auto" 4 xmlns:tools="http://schemas.android.com/tools" 5 android:layout_width="match_parent" 6 android:layout_height="match_parent" 7 tools:context=".MainActivity" 8 android:orientation="vertical"> 9 10 <Button 11 android:id="@+id/bt_1" 12 android:layout_width="wrap_content" 13 android:layout_height="wrap_content" 14 android:text="开启访问百度" 15 android:textSize="30dp" 16 android:onClick="click1" /> 17 18 </LinearLayout>
1 package com.example.myapplication103; 2 import android.net.Uri; 3 import android.os.Bundle; 4 import android.app.Activity; 5 import android.content.Intent; 6 import android.util.Log; 7 import android.view.Menu; 8 import android.view.View; 9 10 public class MainActivity extends Activity { 11 12 @Override 13 protected void onCreate(Bundle savedInstanceState) { 14 super.onCreate(savedInstanceState); 15 setContentView(R.layout.activity_main); 16 Log.e("MainActivity", "调用oncreate"); 17 } 18 19 @Override 20 protected void onStart() { 21 // TODO Auto-generated method stub 22 super.onStart(); 23 Log.e("MainActivity", "调用onstart"); 24 } 25 @Override 26 protected void onResume() { 27 // TODO Auto-generated method stub 28 super.onResume(); 29 Log.e("MainActivity", "调用onresume"); 30 } 31 @Override 32 protected void onPause() { 33 // TODO Auto-generated method stub 34 super.onPause(); 35 Log.e("MainActivity", "调用onpause"); 36 } 37 38 @Override 39 protected void onStop() { 40 // TODO Auto-generated method stub 41 super.onStop(); 42 Log.e("MainActivity", "调用onstop"); 43 } 44 45 @Override 46 protected void onDestroy() { 47 // TODO Auto-generated method stub 48 super.onDestroy(); 49 Log.e("MainActivity", "调用ondestroy"); 50 } 51 52 @Override 53 protected void onRestart() { 54 // TODO Auto-generated method stub 55 super.onRestart(); 56 Log.e("MainActivity", "调用onRestart"); 57 } 58 59 public void click1(View view){ 60 Intent intent=new Intent(); 61 intent.setAction("android.intent.action.VIEW"); 62 intent.setData(Uri.parse("http://www.baidu.com")); 63 startActivity(intent); 64 65 } 66 67 }
3.2个edittext,4个按钮一个textview,实现简单计算器
1 <?xml version="1.0" encoding="utf-8"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3 xmlns:tools="http://schemas.android.com/tools" 4 android:layout_width="match_parent" 5 android:layout_height="match_parent" 6 android:orientation="vertical" 7 android:id="@+id/xb_1" 8 tools:context=".Main4Activity"> 9 10 <EditText 11 android:id="@+id/et_1" 12 android:layout_width="200dp" 13 android:layout_height="wrap_content" 14 android:layout_marginTop="100dp" 15 android:layout_marginLeft="100dp" 16 android:layout_marginRight="100dp" 17 android:inputType="number" 18 android:gravity="center" 19 android:textSize="20sp"/> 20 21 <EditText 22 android:id="@+id/et_2" 23 android:layout_width="200dp" 24 android:layout_height="wrap_content" 25 android:layout_marginLeft="100dp" 26 android:layout_marginRight="100dp" 27 android:inputType="number" 28 android:gravity="center" 29 android:textSize="20sp"/> 30 <LinearLayout 31 android:id="@+id/xb_2" 32 android:layout_width="wrap_content" 33 android:layout_height="wrap_content" 34 android:layout_marginTop="20dp" 35 android:layout_marginLeft="20dp" 36 android:layout_marginRight="20dp" 37 android:orientation="horizontal"> 38 <Button 39 android:id="@+id/btn_1" 40 android:layout_width="wrap_content" 41 android:layout_height="wrap_content" 42 android:text="加(+)"/> 43 <Button 44 android:id="@+id/btn_2" 45 android:layout_width="wrap_content" 46 android:layout_height="wrap_content" 47 android:text="减(-)"/> 48 <Button 49 android:id="@+id/btn_3" 50 android:layout_width="wrap_content" 51 android:layout_height="wrap_content" 52 android:text="乘(*)"/> 53 <Button 54 android:id="@+id/btn_4" 55 android:layout_width="wrap_content" 56 android:layout_height="wrap_content" 57 android:text="除(/)"/> 58 </LinearLayout> 59 <TextView 60 android:id="@+id/tv_1" 61 android:layout_width="wrap_content" 62 android:layout_height="wrap_content" 63 android:layout_marginTop="50dp" 64 android:layout_marginLeft="150dp" 65 android:layout_marginRight="150dp" 66 android:textSize="30sp" 67 android:gravity="center" 68 android:textColor="#06C6F7" 69 android:text="结果为"/> 70 71 </LinearLayout>
1 package com.example.week7; 2 3 import androidx.appcompat.app.AppCompatActivity; 4 import android.os.Bundle; 5 import android.view.View; 6 import android.widget.Button; 7 import android.widget.EditText; 8 import android.widget.TextView; 9 import android.widget.Toast; 10 11 public class Main4Activity extends AppCompatActivity { 12 private TextView tv_1; 13 private Button btn_1,btn_2,btn_3,btn_4; 14 private EditText et_1,et_2; 15 16 @Override 17 protected void onCreate(Bundle savedInstanceState) { 18 super.onCreate(savedInstanceState); 19 setContentView(R.layout.activity_main4); 20 btn_1=(Button)this.findViewById(R.id.btn_1); 21 btn_2=(Button)findViewById(R.id.btn_2); 22 btn_3=(Button)findViewById(R.id.btn_3); 23 btn_4=(Button)findViewById(R.id.btn_4); 24 et_1=(EditText)this.findViewById(R.id.et_1); 25 et_2=(EditText)this.findViewById(R.id.et_2); 26 tv_1=(TextView)this.findViewById(R.id.tv_1); 27 28 btn_1.setOnClickListener(new View.OnClickListener() { 29 @Override 30 public void onClick(View view) { 31 String inputText1=et_1.getText().toString(); 32 String inputText2=et_2.getText().toString(); 33 float num1=Float.valueOf(inputText1).intValue(); 34 float num2=Float.valueOf(inputText2).intValue(); 35 num1=num1+num2; 36 inputText1=String.valueOf(num1); 37 tv_1.setText(inputText1); 38 } 39 }); 40 btn_2.setOnClickListener(new View.OnClickListener() { 41 @Override 42 public void onClick(View view) { 43 String inputText1=et_1.getText().toString(); 44 String inputText2=et_2.getText().toString(); 45 float num1=Float.valueOf(inputText1).intValue(); 46 float num2=Float.valueOf(inputText2).intValue(); 47 num1=num1-num2; 48 inputText1=String.valueOf(num1); 49 tv_1.setText(inputText1); 50 } 51 }); 52 btn_3.setOnClickListener(new View.OnClickListener() { 53 @Override 54 public void onClick(View view) { 55 String inputText1=et_1.getText().toString(); 56 String inputText2=et_2.getText().toString(); 57 float num1=Float.valueOf(inputText1).intValue(); 58 float num2=Float.valueOf(inputText2).intValue(); 59 num1=num1*num2; 60 inputText1=String.valueOf(num1); 61 tv_1.setText(inputText1); 62 } 63 }); 64 btn_4.setOnClickListener(new View.OnClickListener() { 65 @Override 66 public void onClick(View view) { 67 String inputText1=et_1.getText().toString(); 68 String inputText2=et_2.getText().toString(); 69 float num1=Float.valueOf(inputText1).intValue(); 70 float num2=Float.valueOf(inputText2).intValue(); 71 if (num2==0){ 72 Toast.makeText(Main4Activity.this,"除数不能为0",Toast.LENGTH_LONG).show(); 73 }else{ 74 num1=num1/num2; 75 inputText1=String.valueOf(num1); 76 tv_1.setText(inputText1); 77 } 78 } 79 }); 80 } 81 }