注意修改名字
<Button android:id="@+id/button1" android:layout_height="wrap_content" android:layout_width="match_parent" android:text="按钮1" />
public class FirstActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.first_layout); } }
//空项目会自动生成,这是主启动,现在需要手动添加 <activity android:name=".FirstActivity" android:label="这是第一个活动" > <intent-filter> <action android:name="android.intent.action.MAIN"/> <category android:name="android.intent.category.LAUNCHER"/> </intent-filter> </activity>
public class FirstActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.first_layout); //新添加的 Button button1=(Button)findViewById(R.id.button1); button1.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View v){ Toast.makeText(FirstActivity.this,"你点击了按钮1",Toast.LENGTH_SHORT).show(); } }); } }
<?xml version="1.0" encoding="utf-8"?> <menu xmlns:android="http://schemas.android.com/apk/res/android"> <item android:id="@+id/add_item" android:title="Add" /> <item android:id="@+id/remove_item" android:title="Remove" /> </menu>
public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main,menu); return true; }
@Override // 重写菜单触发事件 public boolean onOptionsItemSelected(MenuItem item) { switch(item.getItemId()) { case R.id.add_item: Toast.makeText(FirstActivity.this, "你点击了创建按钮", Toast.LENGTH_SHORT).show(); break; case R.id.remove_item: Toast.makeText(FirstActivity.this, "你点击了移除按钮", Toast.LENGTH_SHORT).show(); break; default: } return true; }
最终代码
package com.example.student.activitytest; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Button; import android.widget.Toast; public class FirstActivity extends AppCompatActivity { @Override //重写创建菜单事件 public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main,menu); return true; } @Override // 主界面初始构造函数 protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.first_layout); Button button1=(Button)findViewById(R.id.button1); button1.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View v){ Toast.makeText(FirstActivity.this,"你点击了按钮1",Toast.LENGTH_SHORT).show(); } }); } @Override // 重写菜单触发事件 public boolean onOptionsItemSelected(MenuItem item) { switch(item.getItemId()) { case R.id.add_item: Toast.makeText(FirstActivity.this, "你点击了创建按钮", Toast.LENGTH_SHORT).show(); break; case R.id.remove_item: Toast.makeText(FirstActivity.this, "你点击了移除按钮", Toast.LENGTH_SHORT).show(); break; default: } return true; } }
如何销毁一个活动
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/button2" android:layout_height="wrap_content" android:layout_width="match_parent" android:text="按钮2" /> </LinearLayout>
protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_second_layout); }
public void onClick(View v){ Toast.makeText(FirstActivity.this,"你点击了按钮1,准备切换活动2",Toast.LENGTH_SHORT).show(); Intent intent=new Intent(FirstActivity.this,second_layout.class); startActivity(intent); // finish(); } }); }
<activity android:name=".second_layout">
<intent-filter>
<action android:name="com.example.activitytest.ACTION_START" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
public void onClick(View v){ Toast.makeText(FirstActivity.this,"你点击了按钮1,准备切换活动2",Toast.LENGTH_SHORT).show(); // Intent intent=new Intent(FirstActivity.this,second_layout.class); Intent intent=new Intent("com.example.activitytest.ACTION_START"); startActivity(intent); // finish(); } }); }
public void onClick(View v){
Toast.makeText(FirstActivity.this,"你点击了按钮1,准备切换活动2",Toast.LENGTH_SHORT).show();
// Intent intent=new Intent(FirstActivity.this,SecondActivity .class); //显式调用
Intent intent=new Intent("com.example.activitytest.ACTION_START");//隐士调用1+默认
intent.addCategory("com.example.activitytest.MY_CATEGORY");//隐士调用2+增加一个自定义
startActivity(intent);
}
});
}
<activity android:name=".second_layout"> <intent-filter> <action android:name="com.example.activitytest.ACTION_START" /> <category android:name="android.intent.category.DEFAULT" /> <category android:name="com.example.activitytest.MY_CATEGORY" /> </intent-filter> </activity>
button1.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View v){ Toast.makeText(FirstActivity.this,"你点击了按钮1,准备切换活动2",Toast.LENGTH_SHORT).show(); // 显式 // Intent intent=new Intent(FirstActivity.this,second_layout.class); //隐式 // Intent intent=new Intent("com.example.activitytest.ACTION_START"); // intent.addCategory("com.example.activitytest.MY_CATEGORY"); // 开启别的程序-网页 Intent intent=new Intent("android.intent.action.VIEW"); intent.setData(Uri.parse("http://www.baidu.com")); startActivity(intent); } }); }
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/button3" android:layout_height="wrap_content" android:layout_width="match_parent" android:text="按钮3" /> </LinearLayout>
修改后
<activity android:name=".ThirdActivity">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<data android:scheme="http" />
</intent-filter>
</activity>
按键代码:
Button button1=(Button)findViewById(R.id.button1); button1.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View v){ Toast.makeText(FirstActivity.this,"你点击了按钮1",Toast.LENGTH_SHORT).show(); // Intent intent=new Intent(FirstActivity.this,SecondActivity .class); //显式调用 // Intent intent=new Intent("com.example.activitytest.ACTION_START");//隐士调用1+默认 // intent.addCategory("com.example.activitytest.MY_CATEGORY");//隐士调用2+增加一个自定义 // Intent intent=new Intent("android.intent.action.VIEW"); // 网页测试 // intent.setData(Uri.parse("http://www.baidu.com"));
Intent intent=new Intent(Intent.ACTION_DIAL); intent.setData(Uri.parse("tel:10086")); startActivity(intent); } }); }
传递数据: