一.Activity跳转

1.选择Empty Views Activity创建项目

2.创建OtherActivity3.修改activity_main.xml

android:id="@+id/btnJumpOther"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="跳转到other页面"

app:layout_constraintBottom_toBottomOf="parent"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintHorizontal_bias="0.508"

app:layout_constraintStart_toStartOf="parent"

app:layout_constraintTop_toTopOf="parent"

/>

4.修改activity_other.xml

android:text="Other页面"

android:layout_width="wrap_content"

android:layout_height="wrap_content" android:id="@+id/Other"

app:layout_constraintTop_toTopOf="parent"

app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintStart_toStartOf="parent"/>

5.页面跳转实现

public class MainActivity extends AppCompatActivity {

private Button btnJumpOther;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btnJumpOther=findViewById(R.id.btnJumpOther);

btnJumpOther.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

Intent intent=new Intent(MainActivity.this,OtherActivity.class);

startActivity(intent);

}

});

}

}

二.Activity带参跳转

带参跳转则需要使用 Intent 的 putExtra(键,值)方法来放入参数，然后在OtherActivity中使用 getIntent().get类型Extra(键)来取得值

MAinActivity按钮的点击事件

只比前面多了一行代码

intent.putExtra("key", "我是参数");

public class MainActivity extends AppCompatActivity {

private Button btnJumpOther;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btnJumpOther=findViewById(R.id.btnJumpOther);

btnJumpOther.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

Intent intent=new Intent(MainActivity.this,OtherActivity.class);

intent.putExtra("key","我是参数");

startActivity(intent);

}

});

}

}

OtherActivity中的代码

public class OtherActivity extends AppCompatActivity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_other);

TextView Other=findViewById(R.id.Other);

Intent intent = getIntent();

String value = intent.getStringExtra("key");

Other.setText(value);

}

}

三.Activity带参返回

activity_main.xml

android:id="@+id/btnJumpMain"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="跳转到other页面"

app:layout_constraintBottom_toBottomOf="parent"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintHorizontal_bias="0.508"

app:layout_constraintStart_toStartOf="parent"

app:layout_constraintTop_toTopOf="parent"

/>

android:text="Hello World"

android:layout_width="wrap_content"

android:layout_height="wrap_content" android:id="@+id/receiver"

app:layout_constraintTop_toTopOf="parent"

app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintStart_toStartOf="parent" app:layout_constraintHorizontal_bias="0.498"

app:layout_constraintVertical_bias="0.427"/>

activity_other.xml

android:id="@+id/btnJumpMain"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="跳转到Main页面"

app:layout_constraintBottom_toBottomOf="parent"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintHorizontal_bias="0.508"

app:layout_constraintStart_toStartOf="parent"

app:layout_constraintTop_toTopOf="parent"

/>

android:text="TextView"

android:layout_width="wrap_content"

android:layout_height="wrap_content" android:id="@+id/receiver"

app:layout_constraintTop_toTopOf="parent"

android:layout_marginBottom="25dp"

app:layout_constraintBottom_toBottomOf="parent"

app:layout_constraintVertical_bias="0.444" app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintStart_toStartOf="parent" app:layout_constraintHorizontal_bias="0.498"/>

MainActivity中的代码

public class MainActivity extends AppCompatActivity {

// 定义请求码，不同界面的跳转请求码要求不同，为了识别是哪个控件传递数据

public final static int sendUser = 1;

private TextView receiver;

private Button btnJumpOther;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btnJumpOther=findViewById(R.id.btnJumpMain);

receiver=findViewById(R.id.receiver);

btnJumpOther.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

Intent intent=new Intent(MainActivity.this,OtherActivity.class);

intent.putExtra("key","接收到数据了，现在通知OtherActivity");

// 启动意图(意图，请求码(int)) 请求码最好使用 final static定义 方便识别

startActivityForResult(intent,sendUser);

}

});

}

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

super.onActivityResult(requestCode, resultCode, data);

// 如果请求码为 sendUser 返回码 为 RESULT_OK RESULT_OK为系统自定义的int值为 -1

if(requestCode==sendUser&&resultCode==RESULT_OK){

// 在TextView中设置返回信息

receiver.setText(data.getStringExtra("key"));

}

}

}

OtherActivity中的代码

public class OtherActivity extends AppCompatActivity {

private Intent intent;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_other);

TextView Other=findViewById(R.id.receiver);

intent = getIntent();

String value = intent.getStringExtra("key");

Other.setText(value);

Button btnJumpMain = findViewById(R.id.btnJumpMain);

btnJumpMain.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

// 发送返回数据 key可自己定义，但前后必须一样

intent.putExtra("key","接收到数据了，现在通知MainActivity");

// RESULT_OK 系统定义的int 值 为-1

setResult(RESULT_OK,intent);

// 关闭当前 Activity

finish();

}

});

}

}