如何通过其他活动传递和获取字符串值？

现在的场景是，我将开始2个活动以获取一些String值，然后在第3个活动中，我将捕获String值，然后将比较捕获的String并更改图像源

例子：

1. 选择程序
2. 选择日期（周一至周五）
3. 捕获了从程序到一天的String传递，并将两者结合起来并通过ImageView传递给活动

我再次编辑了代码。

第一次活动

enter code here

public class TestSchedule extends Activity {

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

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.test_schedule, menu);
    return true;
}

public void SSD(View view){
    String programme = "SSD";
    Intent intent = new Intent(TestSchedule.this,TextDay.class);
    intent.putExtra("prog", programme);
    startActivity(intent);
    }

public void EIS(View view){
    String programme = "EIS";
    Intent intent = new Intent(TestSchedule.this,TextDay.class);
    intent.putExtra("prog", programme);
    startActivity(intent);
    }

public void IS(View view){
    String programme = "IS";
    Intent intent = new Intent(TestSchedule.this,TextDay.class);
    intent.putExtra("prog", programme);
    startActivity(intent);
    }

public void IT(View view){
    String programme = "IT";
    Intent intent = new Intent(TestSchedule.this,TextDay.class);
    intent.putExtra("prog", programme);
    startActivity(intent);
    }

}

第二次活动

public class TextDay extends Activity {

String programme;

private void getData(){
    Bundle extras = getIntent().getExtras();
    if(extras != null){
        programme = extras.getString("prog");
    }
}

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

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.text_day, menu);
    return true;
}

public void monday(View view){
    if(programme.equals("SSD")){
        String programDay = "SSDMon";
        Intent intent = new Intent(TextDay.this, TestShow.class);
        intent.putExtra("progDay", programDay);
        startActivity(intent);
    }
    if(programme.equals("EIS")){
        String programDay = "EISMon";
        Intent intent = new Intent(TextDay.this, TestShow.class);
        intent.putExtra("progDay", programDay);
        startActivity(intent);
    }
    if(programme.equals("IS")){
        String programDay = "ISMon";
        Intent intent = new Intent(TextDay.this, TestShow.class);
        intent.putExtra("progDay", programDay);
        startActivity(intent);
    }
    if(programme.equals("IT")){
        String programDay = "ITMon";
        Intent intent = new Intent(TextDay.this, TestShow.class);
        intent.putExtra("progDay", programDay);
        startActivity(intent);
    }   
    }
}

第三次活动将捕获并更改图像源

enter code here

public class TestShow extends Activity {

ImageView image;
String table;

private void getData(){
    Bundle extras = getIntent().getExtras();
    if(extras != null){
        table = extras.getString("progDay");
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test_show);
    getData();
    image = (ImageView) findViewById(R.id.showTimeTable);
    if(table.equals("SSDMonday")){
        image.setImageResource(R.drawable.ssd_mon);
    }
    if(table.equals("EISMonday")){
        image.setImageResource(R.drawable.eis_mon);
    }
    if(table.equals("ISMonday")){
        image.setImageResource(R.drawable.is_mon);
    }
    if(table.equals("ITMonday")){
        image.setImageResource(R.drawable.it_mon);
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.test_show, menu);
    return true;
}

}